Political donations and the gender gap during COVID-19.

What effect has the COVID-19 pandemic had on the political donations gender gap in Canada? Drawing on data from two national surveys conducted in May and August 2020, as well as Elections Canada data from 2019 and 2020, we find an overall decline in contributions to political parties and a reduced but still significant gender gap, with women less likely to donate to political parties than men.

Reliability of automated biochemical identification of Burkholderia pseudomallei is regionally dependent.

Misidentifications of Burkholderia pseudomallei as Burkholderia cepacia by Vitek 2 have occurred. Multidimensional scaling ordination of biochemical profiles of 217 Malaysian and Australian B. pseudomallei isolates found clustering of misidentified B. pseudomallei isolates from Malaysian Borneo. Specificity of B. pseudomallei identification in Vitek 2 and potentially other automated identification systems is regionally dependent.

Isolated limb infusion for in-transit malignant melanoma of the extremity: a well-tolerated but less effective alternative to hyperthermic isolated limb perfusion.

BACKGROUND: Isolated limb infusion (ILI) is a recently described minimally invasive technique developed in Australia for delivering regional chemotherapy. This study examined the efficacy and toxicity of ILI, compared to hyperthermic isolated limb perfusion (HILP), in treating extremity in-transit melanoma. METHODS: Variables from a prospective single institution database of 120 regionally treated melanoma patients (1995-2007) were compared using chi-square analysis. This included 61 consecutive ILI treatments in 58 patients and 59 HILP treatments in 54 patients. Response was defined at 3 months using the response evaluation criteria in solid tumors (RECIST). ILI was performed using melphalan (LPAM) and dactinomycin for 30 min after limb temperature reached 37 degrees C. HILP was performed using LPAM for 60 min after limb temperature reached 38.5 degrees C. RESULTS: For ILI (n = 61), the complete response (CR) rate was 30%, the partial response (PR) rate was 14%, and there was no response (NR) in 56% of patients. The median duration of CR was 12 months and 18% of patients experienced (grade >or=3) toxicity. HILP (n = 59) was associated with a better (P < 0.001) response rate (CR 57%, PR 31%, and NR 12%) however, more patients (32%) experienced grade >or=3 toxicity (P = 0.037). The dose of LPAM was corrected for ideal body weight (IBW) in 40 out of 61 ILI procedures, and 13 of 59 HILP procedures. This dosing modification was associated with decreased toxicity (P = 0.024) without diminishing response. CONCLUSION: ILI was found to be a well-tolerated alternative to HILP. While ILI does not appear to be as effective as HILP, it does seem to be associated with less morbidity.

Current antimicrobial susceptibility of first-episode melioidosis Burkholderia pseudomallei isolates from the Northern Territory, Australia.

Burkholderia pseudomallei is a saprophytic Gram-negative bacterium responsible for the tropical infectious disease melioidosis. Melioidosis is endemic to northern Australia and Southeast Asia. In this study, 234 isolates of B. pseudomallei obtained from the first positive clinical specimen from 234 consecutive patients diagnosed with melioidosis between October 2009 and September 2012 were reviewed. All isolates were susceptible to meropenem and ceftazidime. In total, 226 isolates (96.6%) were susceptible to doxycycline and 232 (99.1%) were susceptible to trimethoprim/sulfamethoxazole (TMP/SMX; co-trimoxazole). Primary resistance of B. pseudomallei to ceftazidime and/or meropenem is exceedingly rare and clinicians can be confident in the current treatment guidelines for melioidosis. Whether the very low rates of TMP/SMX resistance seen in Australia reflect the global situation requires further studies using Etest, especially to clarify the rate of resistance in Thailand.

Sorafenib, a multikinase inhibitor, enhances the response of melanoma to regional chemotherapy.

Melanoma responds poorly to standard chemotherapy due to its intrinsic chemoresistance. Multiple genetic and molecular defects, including an activating mutation in the BRaf kinase gene, are associated with melanoma, and the resulting alterations in signal transduction pathways regulating proliferation and apoptosis are thought to contribute to its chemoresistance. Sorafenib, a multikinase inhibitor that targets BRaf kinase, is Food and Drug Administration approved for use in advanced renal cell and hepatocellular carcinomas. Although sorafenib has shown little promise as a single agent in melanoma patients, recent clinical trials suggest that, when combined with chemotherapy, it may have more benefit. We evaluated the ability of sorafenib to augment the cytotoxic effects of melphalan, a regional chemotherapeutic agent, and temozolomide, used in systemic and regional treatment of melanoma, on a panel of 24 human melanoma-derived cell lines and in an animal model of melanoma. Marked differences in response to 10 micromol/L sorafenib alone were observed in vitro across cell lines. Response to sorafenib significantly correlated with extracellular signal-regulated kinase (ERK) downregulation and loss of Mcl-1 expression (P < 0.05). Experiments with the mitogen-activated protein kinase/ERK kinase inhibitor U0126 suggest a unique role for ERK downregulation in the observed effects. Sorafenib in combination with melphalan or temozolomide led to significantly improved responses in vitro (P < 0.05). In the animal model of melanoma, sorafenib in combination with regional melphalan or regional temozolomide was more effective than either treatment alone in slowing tumor growth. These results show that sorafenib in combination with chemotherapy provides a novel approach to enhance chemotherapeutic efficacy in the regional treatment of in-transit melanoma.

A phase 1 study of systemic ADH-1 in combination with melphalan via isolated limb infusion in patients with locally advanced in-transit malignant melanoma.

BACKGROUND: Isolated limb infusion with melphalan is a well-tolerated treatment for patients with in-transit extremity melanoma with an approximately 30% complete response (CR) rate. ADH-1 is a cyclic pentapeptide that disrupts N-cadherin adhesion complexes and when given systemically in a preclinical model of regional melphalan therapy demonstrated synergistic antitumor activity. A phase 1 dose escalation study to evaluate the safety, tolerability, pharmacokinetics, and antitumor activity of systemic ADH-1 in combination with melphalan via isolated limb infusion in patients with in-transit extremity melanoma was performed. METHODS: Dose escalation cohorts of 3 patients each received 1000, 2000, and 4000 mg (10 patients) of ADH-1 administered intravenously on Days 1 and 8 with standard dose melphalan via isolated limb infusion on Day 1. N-cadherin immunohistochemistry staining and quantitative polymerase chain reaction analysis were performed on pretreatment tumor. Response was defined at 3 months using modified Response Evaluation Criteria in Solid Tumors. RESULTS: Sixteen patients have been treated with no observed dose-limiting toxicities. Common treatment-related grade 1 or 2 toxicities included skin/dermatologic (n=14) and pain (n=12). Grade 3 toxicities included shortness of breath (n=1), hypertension (n=1), serologic toxicities (n=4), and 1 grade 4 creatine phosphokinase elevation. In-field responses included 8 CRs, 2 partial responses, 1 stable disease, and 5 progressive diseases. Pharmacokinetic analysis demonstrated increasing ADH-1 concentrations at each dose and minimal variability in melphalan drug levels. CONCLUSIONS: Systemic ADH-1 at a dose of 4000 mg on Days 1 and 8 in combination with melphalan via isolated limb infusion is a well-tolerated, novel targeted therapy approach to regionally advanced melanoma. The number of CRs exceeded expectations, suggesting that targeting N-cadherin may be a new strategy for overcoming melanoma chemoresistance.

A multi-institutional experience of isolated limb infusion: defining response and toxicity in the US.

BACKGROUND: Isolated limb infusion (ILI) is a minimally invasive approach for treating in-transit extremity melanoma, with only two US single-center studies reported. Establishing response and toxicity to ILI as compared with hyperthermic isolated limb perfusion is important for optimizing future regional chemotherapeutic strategies in melanoma. STUDY DESIGN: Patient characteristics and procedural variables were collected retrospectively from 162 ILIs performed at 8 institutions (2001 to 2008) and compared using chi-square and Student's t-test. ILIs were performed for 30 minutes in patients with in-transit melanoma. Melphalan dose was corrected for ideal body weight (IBW) in 42% (n = 68) of procedures. Response was determined at 3 months by Response Evaluation Criteria in Solid Tumors; toxicity was assessed using the Wieberdink Limb Toxicity Scale. RESULTS: In 128 evaluable patients, complete response rate was 31%, partial response rate was 33%, and there was no response in 36% of patients. For all patients (n = 162), 36% had Wieberdink toxicity grade >or=3 with one toxicity-related amputation. On multivariate analysis, smaller limb volumes were associated with better overall response (p = 0.021). Use of papaverine in the circuit to achieve cutaneous vasodilation was associated with better response (p < 0.001) but higher risk of grade >or=3 toxicity (p = 0.001). Correction of melphalan dose for ideal body weight did not alter complete response (p = 0.345), but did lead to marked reduction in toxicity (p < 0.001). CONCLUSIONS: In the first multi-institutional analysis of ILI, a complete response rate of 31% was achieved with acceptable toxicity demonstrating this procedure to be a reasonable alternative to hyperthermic isolated limb perfusion in the management of advanced extremity melanoma.

A mechanical study of rigid plate configurations for sternal fixation.

Rigid metal plates are a promising alternative to wires for reapproximating the sternum after open-heart surgery due to their potential ability to reduce motion at the wound site and thereby reduce the likelihood of post-operative healing complications. Despite initial clinical success, the use of plates has been limited, in part, by insufficient knowledge about their most effective placement. This study compares the ability of five plate configurations to provide stable closure by limiting sternal separation. Commercially available x-shaped and box-shaped plates were used and combinations of parameters (plate type, location, and number of plates) were investigated in vitro. Lateral distraction tests using controlled, uniform loading were conducted on 15 synthetic sterna and the distractions between separated sternum halves were measured at seven locations. Distractions at the xiphoid, a critical region clinically, varied widely from 0.03 +/- 0.53 mm to 4.24 +/- 1.26 mm depending on all three plate parameters. Of the configurations tested, three x-shaped plates and one box-shaped plate resisted sternal separation most effectively. These results provide the first comparison of plate configurations for stabilizing a sternotomy. However, basic mechanical analyses indicate that sternal loading in vivo is non-uniform; future studies will need to accurately quantify in vivo loading to improve in vitro test methods.

In vitro comparison of wire and plate fixation for midline sternotomies.

BACKGROUND: The incidence of severe sternal wound complications in high-risk cardiac patients presents a significant need for more stabile sternal fixation techniques after median sternotomy procedures. Rigid metal plates, a potential alternative to wire fixation, are thought to promote faster sternal healing by reducing motion at the wound site. The goal of this study was to compare the stability provided by commercially available sternal plates with standard wires using an in vitro model. METHODS: Lateral distraction tests were conducted on bisected polyurethane sternal models fixed with either a standard 7 wire configuration (n = 5) or a 3 plate configuration (n = 3). To assure controlled loading, the sternal models were attached to a computer-controlled test machine by a novel tethering system that distributes the total force (180N) equally to eight locations on the sternum. Stability was defined as the ability to restrict sternal separation at seven locations along the midline quantified using digital image analysis. RESULTS: Our results indicate that rigid plate fixation significantly reduced lateral motion relative to wire fixation. The lower sternal region most noticeably benefited from plate fixation as the splaying observed for wire fixation was reduced. CONCLUSIONS: Under these loading conditions, plating increased stability at the midline compared to wires; this increased stability may facilitate the recovery of high-risk patients undergoing cardiac operation. To enhance in vitro testing methods, future studies should incorporate additional in vivo loading conditions applied to the sternum. Alternate plating configurations should also be examined to further increase stability.