Localized Merkel cell carcinoma treatment considerations: a response to the forty-year experience at the Peter MacCallum cancer centre.

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine tumour of the skin with poor prognosis and rising global incidence. A recently published article in BMC Cancer, titled "Merkel cell carcinoma: a forty-year experience at the Peter MacCallum Cancer Centre" (Wang et al.), provides a contemporary analysis of locoregional disease outcomes in Australia which highlights the comparative effectiveness of radiotherapy for excisions with involved margins versus wide local excision. There is a persistent lack of clear, well-defined guidelines to manage MCC in Australia despite experiencing the highest rates globally. The advanced age at onset also provides inherent challenges for optimal management and often, a case-by-case approach is necessary based on patient preferences, baseline function and fitness for surgery. This paper responds to the recently published article by Wang et al. and will expand the discourse regarding management of localized MCC. Specifically, we will discuss the surgical excision approaches; alternative treatment options for MCC including radiotherapy, Mohs micrographic surgery and novel immunotherapy agents being investigated through several clinical trials.

Reproducible isolation of bovine mammary macrophages for analysis of host pathogen interactions.

BACKGROUND: Macrophages residing in milk are vital during intramammary infections. This study sought to develop a method enabling the investigation of macrophage responses to pathogens. Streptococcus uberis is the predominant cause of bovine mastitis UK-wide and its pathogenesis is unusual compared to other intramammary pathogens. Previous studies utilise macrophage cell lines, isolated bovine blood derived monocytes, or macrophages from raw milk through complex or inconsistent strategies such as fluorescence activated cell sorting (FACS), centrifugation and selective adherence, and CD14 antibody-microbeads. The centrifuge steps required in the initial stages often damage cells. Thus, the aim of this study was to develop a reliable, reproducible, and cost-effective method for isolating mammary macrophages from milk in a way that allows their culture, challenge with bacteria, and measurement of their response ex-vivo. RESULTS: This method achieves an average yield of 1.27 × 107 cells per litre of milk. Whole milk with somatic cell range of 45-65 cells/µL produced excellent yields, with efficient isolations accomplished with up to 150 cells/µL. This strategy uses milk diluted in PAE buffer to enable low-speed centrifugation steps followed by seeding on tissue-culture-treated plastic. Seeding 1,000,000 milk-extracted cells onto tissue culture plates was sufficient to obtain 50,000 macrophage. Isolated macrophage remained responsive to challenge, with the highest concentration of IL-1ß measured by ELISA at 20 h after challenge with S. uberis. In this model, the optimal multiplicity of infection was found to be 50:1 bacteria:macrophage. No difference in IL-1ß production was found between macrophages challenged with live or heat-killed S. uberis. Standardisation of the production of IL-1ß to that obtained following macrophage stimulation with LPS allowed for comparisons between preparations. CONCLUSIONS: A cost-effective method, utilising low-speed centrifugation followed by adherence to plastic, was established to isolate bovine mammary macrophages from raw milk. This method was shown to be appropriate for bacterial challenge, therefore providing a cost-effective, ex-vivo, and non-invasive model of macrophage-pathogen interactions. The optimal multiplicity of infection for S. uberis challenge was demonstrated and a method for standardisation against LPS described which removes sample variation. This robust method enables, reproducible and reliable interrogation of critical pathogen-host interactions which occur in the mammary gland.

May Measurement Month 2021: an analysis of blood pressure screening results from Australia.

May Measurement Month (MMM) is a global and national blood pressure (BP) screening campaign initiated by the International Society of Hypertension to improve awareness of BP worldwide. This study reports on the findings of the MMM21 campaign in Australia. Adult participants (≥18 years) were screened through opportunistic sampling across Australia between 1 May and 30 November 2021. Trained volunteers recorded standardized BP measurements from community volunteer participants along with demographic data, lifestyle factors, comorbidities, and history of COVID-19 infection and vaccination. Hypertension was defined as systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg and/or taking antihypertensive medication. Data were collated and analysed centrally using the current MMM protocol and presented after the imputation of missing BP readings. A total of 1307 participants were screened in 2021, comprising 652 (49.9%) females and 654 (50.0%) males with a mean age of 48 years (SD 20.1). Of all 1307 participants, 524 (40.1%) had hypertension. Of participants with hypertension, 65.4% were aware and 59.3% were on antihypertensive medication. Of 311 participants on antihypertensive medication, 54.7% had controlled BP. Of all 524 participants with hypertension, 32.5% had controlled BP. The current 2021 data may indicate some progress in creating BP awareness; however, consecutive Australian data obtained since 2017 demonstrated stagnating treatment, and control rates compared with global rates and those in other high-income countries. Concerted efforts from all stakeholders will be required to further improve BP awareness, treatment, and control rates in Australia.

A core genome multi-locus sequence typing scheme for Streptococcus uberis: an evolution in typing a genetically diverse pathogen.

Streptococcus uberis is a globally endemic and poorly controlled cause of bovine mastitis impacting the sustainability of the modern dairy industry. A core genome was derived from 579 newly sequenced S. uberis isolates, along with 305 publicly available genome sequences of S. uberis isolated from 11 countries around the world and used to develop a core genome multi-locus sequence typing (cgMLST) scheme. The S. uberis core genome comprised 1475 genes, and these were used to identify 1447 curated loci that were indexed into the cgMLST scheme. This was able to type 1012 of 1037 (>97  %) isolates used and differentiated the associated sequences into 932 discrete core genome sequence types (cgSTs). Analysis of the phylogenetic relationships of cgSTs revealed no clear clustering of isolates based on metadata such as disease status or year of isolation. Geographical clustering of cgSTs was limited to identification of a UK-centric clade, but cgSTs from UK isolates were also dispersed with those originating from other geographical regions across the entire phylogenetic topology. The cgMLST scheme offers a new tool for the detailed analysis of this globally important pathogen of dairy cattle. Initial analysis has re-emphasized and exemplified the genetically diverse nature of the global population of this opportunistic pathogen.