The impact of coronavirus-19 vaccination on anti-nuclear cytoplasmic antibody vasculitis hospitalisations in a Sydney health network.

There have been reports of COVID-19 vaccination triggering anti-nuclear cytoplasmic antibody (ANCA)-associated vasculitis (AAV), but no robust studies have examined the link. This retrospective cohort study assessed the impact of COVID vaccination on the rate of denovo and relapsed AAV in a Sydney Local Health District from 2018 to 2022. Despite more than 95% of the population receiving vaccination, the case rate of AAV was stable. These findings do not support a relationship between COVID vaccination and AAV.

Patterns of biopsy-proven renal disease in people living with HIV: 10 years experience in Sydney, Australia.

BACKGROUND: Acute and chronic kidney diseases are important comorbidities in People Living With HIV (PLWH). Biopsy is often pursued in this cohort with ongoing renal impairment without a clear aetiology, in order to establish the diagnosis and to guide management. Despite the importance of renal disease in PLWH, there is a paucity of biopsy data-especially in the Australian setting. Consequently, who and when to biopsy is mainly based on clinical experience. The aims of this study were to describe biopsy-proven renal disease in PLWH at our institution and to assess for correlation between any demographic or laboratory characteristics with histological diagnosis. METHODS: A retrospective review of all PLWH who underwent renal biopsy between January 2010 and December 2020 at Royal Prince Alfred Hospital, Sydney, Australia was performed. All PLWH over 18 years, who were not transplant recipients were included. Demographic, laboratory and biopsy data was extracted from the electronic medical records. Basic descriptive statistics were performed, and correlation was assessed using chi square and Kendall's coefficient of rank test. RESULTS: 19 renal biopsies were included in the study. The majority of PLWH were Australian born (53%), male (84%) and had a mean age of 48 years (SD 13). Comorbid hypertension and diabetes were present in 74% and 21% of people respectively. The mean serum creatinine was 132 µmol/L (SD 55) and the mean estimated glomerular filtration rate (eGFR) was 61 ml/min/1.73m2 (SD 24). The most common histological diagnosis was tubulointerstial nephritis in 5 people (24%). Hypertensive glomerulosclerosis and IgA nephropathy were present in 4 (19%) and 3 (14%) people respectively. There were no cases of HIV-associated nephropathy. There was no significant correlation between any cohort characteristics and diagnoses. CONCLUSIONS: This study represents the first description of biopsy-proven kidney disease in the HIV-infected population of Australia. Our results support the use of renal biopsy in PLWH with ongoing renal impairment for accurate diagnosis and to guide further management. Although a small sample size, our study is larger than other published international biopsy studies.

TRPC1 is a differential regulator of hypoxia-mediated events and Akt signalling in PTEN-deficient breast cancer cells.

Hypoxia is a feature of the tumour microenvironment that promotes invasiveness, resistance to chemotherapeutics and cell survival. Our studies identify the transient receptor potential canonical-1 (TRPC1) ion channel as a key component of responses to hypoxia in breast cancer cells. This regulation includes control of specific epithelial to mesenchymal transition (EMT) events and hypoxia-mediated activation of signalling pathways such as activation of the EGFR, STAT3 and the autophagy marker LC3B, through hypoxia-inducible factor-1α (HIF1α)-dependent and -independent mechanisms. TRPC1 regulated HIF1α levels in PTEN-deficient MDA-MB-468 and HCC1569 breast cancer cell lines. This regulation arises from effects on the constitutive translation of HIF1α under normoxic conditions via an Akt-dependent pathway. In further support of the role of TRPC1 in EMT, its expression is closely associated with EMT- and metastasis-related genes in breast tumours, and is enhanced in basal B breast cancer cell lines. TRPC1 expression is also significantly prognostic for basal breast cancers, particularly those classified as lymph node positive. The defined roles of TRPC1 identified here could be therapeutically exploited for the control of oncogenic pathways in breast cancer cells.

Renal function change after switching tenofovir disoproxil fumarate for tenofovir alafenamide in the HIV-positive patients of a metropolitan sexual health service.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is widely used in the management of HIV-infection, but has been associated with renal impairment in a small proportion of patients. Tenofovir alafenamide (TAF), a novel prodrug of tenofovir, causes less renal impairment and can improve renal function in patients switched from TDF. The factors which predict improved renal function in patients switching from TDF to TAF have yet to be described. AIM: To determine which patient factors are associated with an improvement in renal function following the switch from a TDF- to a TAF-based HIV antiretroviral regimen. METHODS: A retrospective analysis was performed of a cohort from a publicly funded sexual health clinic in Sydney, Australia. All HIV-positive clinic patients switched from a TDF- to TAF-containing regimen between January 2016 and August 2018 were eligible for inclusion. Laboratory results were obtained from patients' electronic medical records. The statistical significance of differences between pre- and post-switch means was determined by paired t-tests, adjusted for baseline values, and associations between continuous variables by univariate linear regression. RESULTS: 79 patients met inclusion criteria. The majority were male (89%), with a median age of 44 years (IQR: 34.5 to 53). Patients had a mean pre-switch estimated glomerular filtration rate (eGFR) of 95 ± 2 mL/min/1.73 m2, and there was no significant change post-switch (p = 0.062). Pre-switch eGFR was a significant predictor of the magnitude of eGFR change after the switch (p < 0.001), but there was no significant association with age (p = 0.189), cumulative TDF exposure (p = 0.454) or baseline urinary protein to creatinine ratio (p = 0.814). CONCLUSION: While there was no significant difference in mean eGFR, in patients switched from TDF to TAF, baseline eGFR was a significant predictor of the change in eGFR. This suggests that patients on TDF with poorer baseline renal function would benefit more from switching to TAF. Further study to explore this association is warranted.

Triage to electrocardiogram sign-off time in patients with acute coronary syndrome at a metropolitan Sydney hospital.

OBJECTIVE: To compare the time from triage to ECG sign-off in patients with acute coronary syndrome, before and after the introduction of an electronic medical record-integrated ECG workflow system (Epiphany). Additionally, to assess for any correlation between patient characteristics and ECG sign-off times. METHODS: A retrospective, single-centre cohort study was performed at Prince of Wales Hospital, Sydney. Patients were included if they were over 18 years, presented to Prince of Wales Hospital ED during 2021, had an ED diagnosis code of 'ACS', 'UA', 'NSTEMI' or 'STEMI' and were subsequently admitted under the cardiology team. ECG sign-off times and demographic data were compared between patients presenting prior to 29 June (pre-Epiphany group) and those presenting after (post-Epiphany group). Those without ECGs signed-off were excluded. RESULTS: There were 200 patients (100 each group) included in the statistical analysis. There was a significant decrease in the median triage to ECG sign-off time, from 35 min (IQR 18-69) pre-Epiphany, to 21 min (IQR 13-37) post-Epiphany. There were only 10 (5%) patients in the pre-Epiphany group and 16 (8%) in the post-Epiphany group, who had ECG sign-off times less than the 10-min. There was no correlation between gender, triage category, age or time of shift with triage to ECG sign-off time. CONCLUSIONS: The introduction of the Epiphany system has significantly reduced the triage to ECG sign-off time in the ED. Despite this, there remains a large proportion of patients with acute coronary syndrome who do not have an ECG signed-off within the guideline-recommended 10 min.

Characteristics of recently arrived Asian men who have sex with men diagnosed with HIV through sexual health services in Melbourne and Sydney.

OBJECTIVES: Asian men who have sex with men (MSM) who have recently arrived in Australia are an emergent risk group for HIV; however, little is known about how they compare to Australian MSM diagnosed with HIV. This study compared the characteristics of these two groups. METHODS: A retrospective, cross-sectional study of MSM diagnosed with HIV between January 2014 and October 2017 in Melbourne and Sydney public sexual health clinics. Asian MSM were those who had arrived in Australia within 4 years of diagnosis. RESULTS: Among 111 Asian men, 75% spoke a language other than English, 88% did not have Medicare and 61% were international students. Compared with Australian men (n=209), Asian men reported fewer male sexual partners within 12 months (median 4 versus 10, p<0.001), were less likely to have tested for HIV previously (71% versus 89%, p<0.001) and had a lower median CD4 count (326 versus 520, p<0.001). Among Asian men, HIV subtype CRF01-AE was more common (55% versus 16%, p<0.001) and subtype B less common (29% versus 73%, p<0.001). CONCLUSIONS: Asian MSM diagnosed with HIV reported lower risk and had more advanced HIV. Implications for public health: HIV testing and preventative interventions supporting international students are required.

An automated epifluorescence microscopy imaging assay for the identification of phospho-AKT level modulators in breast cancer cells.

AKT is an enzyme of the PI3K/pAKT pathway, regulating proliferation and cell survival. High basal levels of active, phosphorylated AKT (pAKT) are associated with tumor progression and therapeutic resistance in some breast cancer subtypes, including HER2 positive breast cancers. Various stimuli can increase pAKT levels and elevated basal pAKT levels are a feature of PTEN-deficient breast cancer cell lines. The aim of this study was to develop an assay able to identify modulators of pAKT levels using an automated epifluorescence microscope and high content analysis. To develop this assay, we used HCC-1569, a PTEN-deficient, HER2-overexpressing breast cancer cell line with elevated basal pAKT levels. HCC-1569 cells were treated with a selective pharmacological inhibitor of AKT (MK-2206) to reduce basal pAKT levels or EGF to increase pAKT levels. Immunofluorescence images were acquired using an automated epifluorescence microscope and integrated intensity of cytoplasmic pAKT staining was calculated using high content analysis software. Mean and median integrated cytoplasmic intensity were normalized using fold change and standard score to assess assay quality and to identify most robust data analysis. The highest z' factor was achieved for median data normalization using the standard score method (z' = 0.45). Using our developed assay we identified the calcium homeostasis regulating proteins TPRV6, STIM1 and TRPC1 as modulators of pAKT levels in HCC-1569 cells. Calcium signaling controls a diverse array of cellular processes and some calcium homeostasis regulating proteins are involved in modulating pAKT levels in cancer cells. Thus, these identified hits present promising targets for further assessment.