9 research outputs found
Enantioselective Synthesis of Sealutomicin C
The sealutomicins are a family of anthraquinone antibiotics featuring an enediyne (sealutomicin A) or Bergman-cyclized aromatic ring (sealutomicins B–D). Herein we report the development of an enantioselective organocatalytic method for the synthesis of dihydroquinolines and the use of the developed method in the total synthesis of sealutomicin C which features a transannular cyclization of an aryllithium onto a γ-lactone as a second key step
Enantioselective synthesis of sealutomicin C
The sealutomicins are a family of anthraquinone antibiotics featuring an enediyne (sealutomicin A) or Bergman-cyclized aromatic ring (sealutomicins B – D). Herein we report the development of an enantioselective organocatalytic method for the synthesis of dihydroquinolines and the use of the developed method in the total synthesis of sealutomicin C which features a transannular cyclization of an aryl lithium onto a gamma-lactone as a second key step
Peritoneal dialysis-related peritonitis as a risk factor for cardiovascular events
Background: Cardiovascular disease is the leading cause of mortality in peritoneal dialysis (PD) patients. Infection is known to increase the risk of cardiovascular events (CVE); however, no studies have examined the association between PD peritonitis and CVE. Aim: To examine peritonitis as a risk factor for CVE in PD patients. Methods: This retrospective cohort study included all adults undertaking PD for ≥3 months in one Australian health district from 2001 to 2015. Baseline characteristics and peritonitis event information was obtained from the Australian and New Zealand Dialysis and Transplant registry. The Centre for Health Research Illawarra Shoalhaven Population facilitated data linkage using ICD10 coding to capture CVE information. Results: A total of 211 patients was included, with median age of 66 years (interquartile range 54.49–74.45); 64% were male. Peritonitis occurred in 114 (54%) patients and 65 (30.8%) patients experienced a CVE. Identified risk factors for CVE included: cerebrovascular disease (hazard ratio (HR) 2.72, 95% confidence interval (CI) 1.36–5.47), diabetes (HR 2.41, 95% CI 1.47–3.96), coronary artery disease (HR 1.67, 95% CI 1.01–2.77) and age (HR 1.03, 95% CI 1.01–1.06). There was no significant increase in risk of CVE following peritonitis (HR 1.37, 95% CI 0.81–2.32, P = 0.24), even when accounting for age, cerebrovascular disease, diabetes and existing coronary artery disease (HR 1.32, 95% CI 0.78–2.23, P = 0.30). Conclusions: We did not find an increase in the risk of CVE following a peritonitis episode in PD patients. This result may be due to small sample size or rapid peritonitis treatment mitigating cardiovascular risk
Oxidative stress and inflammasome activation in human rhabdomyolysis-induced acute kidney injury
Acute kidney injury (AKI) is a life-threatening complication of rhabdomyolysis. The pathophysiological mechanisms of rhabdomyolysis-induced AKI (RIAKI) have been extensively studied in the murine system, yet clinical translation of this knowledge to humans is lacking. In this study, we investigated the cellular and molecular pathways of human RIAKI. Renal biopsy tissue from a RIAKI patient was examined by quantitative immunohistochemistry (Q-IHC) and compared to healthy kidney cortical tissue. We identified myoglobin casts and uric acid localised to sites of histological tubular injury, consistent with the diagnosis of RIAKI. These pathological features were associated with tubular oxidative stress (4-hydroxynonenal staining), regulated necrosis/necroptosis (phosphorylated mixed-lineage kinase domain-like protein staining) and inflammation (tumour necrosis factor (TNF)-α staining). Expression of these markers was significantly elevated in the RIAKI tissue compared to the healthy control. A tubulointerstitial inflammatory infiltrate accumulated adjacent to these sites of RIAKI oxidative injury, consisting of macrophages (CD68), dendritic cells (CD1c) and T lymphocytes (CD3). Foci of inflammasome activation were co-localised with these immune cell infiltrate, with significantly increased staining for adaptor protein ASC (apoptosis-associated speck-like protein containing a caspase activation and recruitment domain) and active caspase-1 in the RIAKI tissue compared to the healthy control. Our clinical findings identify multiple pathophysiological pathways previously only reported in murine RIAKI, providing first evidence in humans linking deposition of myoglobin and presence of uric acid to tubular oxidative stress/necroptosis, inflammasome activation and necroinflammation
EULAR / PReS standards and recommendations for the transitional care of young people with juvenile onset rheumatic diseases
To develop standards and recommendations for transitional care for young people (YP) with juvenile-onset rheumatic and musculoskeletal diseases (jRMD). The consensus process involved the following: (1) establishing an international expert panel to include patients and representatives from multidisciplinary teams in adult and paediatric rheumatology; (2) a systematic review of published models of transitional care in jRMDs, potential standards and recommendations, strategies for implementation and tools to evaluate services and outcomes; (3) setting the framework, developing the process map and generating a first draft of standards and recommendations; (4) further iteration of recommendations; (5) establishing consensus recommendations with Delphi methodology and (6) establishing standards and quality indicators. The final consensus derived 12 specific recommendations for YP with jRMD focused on transitional care. These included: high-quality, multidisciplinary care starting in early adolescence; the integral role of a transition co-ordinator; transition policies and protocols; efficient communications; transfer documentation; an open electronic-based platform to access resources; appropriate training for paediatric and adult healthcare teams; secure funding to continue treatments and services into adult rheumatology and the need for increased evidence to inform best practice. These consensus-based recommendations inform strategies to reach optimal outcomes in transitional care for YP with jRMD based on available evidence and expert opinion. They need to be implemented in the context of individual countries, healthcare systems and regulatory frameworks
Risk of COVID-19 after natural infection or vaccinationResearch in context
Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health
Recommended from our members
Risk of COVID-19 after natural infection or vaccinationResearch in context
Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health