The Diels-Alder reaction is one of the most effective methods for the synthesis of substituted cyclohexenes. The development of protein catalysts for this reaction remains a major priority, affording new sustainable routes to high value target molecules. Whilst a small number of natural enzymes have been shown capable of catalysing [4 + 2] cycloadditions, there is a need for significant mechanistic understanding of how these prospective Diels-Alderases promote catalysis to underpin their development as biocatalysts for use in synthesis.
View Article and Find Full Text PDFAustralas J Ultrasound Med
February 2024
Introduction/purpose: The routine mid-trimester fetal anatomy ultrasound (FAS) is offered to every pregnant woman and remains critical in the detection of structural fetal anomalies. Our study aimed to determine the prevalence of abnormalities on routine FAS performed by a single operator, who is an experienced sub-specialist in maternal-fetal medicine.
Methods: A retrospective analysis of all routine FAS performed a tertiary private obstetric ultrasound practice in metropolitan Sydney over a 7-year period, August 2015-July 2022.
()-4-Hydroxy-3-methylbut-2-enyl diphosphate reductase, or IspH (formerly known as LytB), catalyzes the terminal step of the bacterial methylerythritol phosphate (MEP) pathway for isoprene synthesis. This step converts ()-4-hydroxy-3-methylbut-2-enyl diphosphate (HMBPP) into one of two possible isomeric products, either isopentenyl diphosphate (IPP) or dimethylallyl diphosphate (DMAPP). This reaction involves the removal of the C4 hydroxyl group of HMBPP and addition of two electrons.
View Article and Find Full Text PDFOehler et al. described an interesting finding, stating that length of stay (LOS) of the donors in the intensive care unit (ICU) did not have an impact on the outcomes and survival of recipients up to 5 years after heart transplantation (HTx) [..
View Article and Find Full Text PDFBackground: This is Part 2 of the first consensus guidelines for optimal care of patients undergoing emergency laparotomy (EL) using an Enhanced Recovery After Surgery (ERAS) approach. This paper addresses intra- and postoperative aspects of care.
Methods: Experts in aspects of management of high-risk and emergency general surgical patients were invited to contribute by the International ERAS Society.
Background: This is Part 3 of the first consensus guidelines for optimal care of patients undergoing emergency laparotomy using an enhanced recovery after surgery (ERAS) approach. This paper addresses organizational aspects of care.
Methods: Experts in management of the high-risk and emergency general surgical patient were invited to contribute by the International ERAS® Society.
Angew Chem Weinheim Bergstr Ger
January 2023
Abyssomicin C and its atropisomer are potent inhibitors of bacterial folate metabolism. They possess complex polycyclic structures, and their biosynthesis has been shown to involve several unusual enzymatic transformations. Using a combination of synthesis and in vitro assays we reveal that AbyV, a cytochrome P450 enzyme from the gene cluster, catalyses a key late-stage epoxidation required for the installation of the characteristic ether-bridged core of abyssomicin C.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2023
Abyssomicin C and its atropisomer are potent inhibitors of bacterial folate metabolism. They possess complex polycyclic structures, and their biosynthesis has been shown to involve several unusual enzymatic transformations. Using a combination of synthesis and in vitro assays we reveal that AbyV, a cytochrome P450 enzyme from the aby gene cluster, catalyses a key late-stage epoxidation required for the installation of the characteristic ether-bridged core of abyssomicin C.
View Article and Find Full Text PDFIncreasing numbers of older people are undergoing surgery with benefits including symptom relief and extended longevity. Despite these benefits, older people are more likely than younger patients to experience postoperative complications, which are predominantly medical as opposed to surgical. Comprehensive Geriatric Assessment and optimisation offers a systematic approach to risk assessment and risk modification in the perioperative period.
View Article and Find Full Text PDFAim: The effect of negative pressure wound therapy (NPWT) on the pathogenesis and outcome of enteroatmospheric fistulation (EAF) in the septic open abdomen (OA) is unclear. This study compares the development and outcome of EAF following NPWT with that occurring in the absence of NPWT.
Methods: Consecutive patients admitted with EAF following abdominal sepsis at a National Reference Centre for intestinal failure between 01 January 2005 and 31 December 2015 were included in this study.
Objectives: Venovenous extracorporeal membrane oxygenation (VV-ECMO) is increasingly being used in acutely deteriorating patients with end-stage lung disease as a bridge to transplantation (BTT). It can allow critically ill recipients to remain eligible for lung transplants (LTx) while reducing pretransplant deconditioning. We analyzed early- and midterm postoperative outcomes of patients on VV-ECMO as a BTT and the impact of preoperative VV-ECMO on posttransplant survival outcomes.
View Article and Find Full Text PDFIn the last years, new trends on patient diagnosis for admission in cardiac intensive care unit (CICU) have been observed, shifting from acute myocardial infarction or acute heart failure to non-cardiac diseases such as sepsis, acute respiratory failure or acute kidney injury. Moreover, thanks to the advances in scientific knowledge and higher availability, there has been increasing use of positive pressure mechanical ventilation which has its implications on the heart. Therefore, there is a growing need for Cardiac intensivists to quickly, noninvasively and repeatedly evaluate various hemodynamic conditions and the response to therapy.
View Article and Find Full Text PDFThe organocatalytic transformation of resorcinols is extremely rare. In this article, we report a highly enantioselective, organocatalytic intramolecular cyclization of these systems by a Friedel-Crafts-type 1,4-addition using a Jørgensen-Hayashi-like organocatalyst with a large silyl protecting group, and show that heat improves reaction yield with virtually no detriment to enantioselectivity. A variety of bicyclic resorcinols were obtained with excellent enantioselectivities (up to 94%).
View Article and Find Full Text PDFAcute kidney injury (AKI) after lung transplantation (LTx) is a common complication. We aimed to assess whether donation after circulatory death (DCD) is associated with an increased risk of AKI and renal replacement therapy (RRT) in the early postoperative period compared to the donation after brain death (DBD). Retrospective data on a cohort (N = 95) of LTx patients (DCD n = 17, DBD n = 78) characterized by no use of ex-vivo lung perfusion were analyzed for the incidence of AKI within 30 postoperative days and incidence of RRT within 7 and 30 days.
View Article and Find Full Text PDFTranscatheter aortic valve implantation (TAVI) has become an established treatment for patients with severe aortic stenosis (AS) in an ever-growing patient population. It is not uncommon for patients who are undergoing TAVI to have technically difficult anatomy, simultaneous severe left ventricular (LV) impairment and/or extensive coronary artery disease. In this case series we present examples where the use of mechanical circulatory support (MCS) facilitated a safe aortic and coronary intervention in extremely complex patients who would have otherwise carried prohibitive procedural risk.
View Article and Find Full Text PDFBackground: Enhanced Recovery After Surgery (ERAS) protocols reduce length of stay, complications and costs for a large number of elective surgical procedures. A similar, structured approach appears to improve outcomes, including mortality, for patients undergoing high-risk emergency general surgery, and specifically emergency laparotomy. These are the first consensus guidelines for optimal care of these patients using an ERAS approach.
View Article and Find Full Text PDFThe introduction of glycosides bearing basic nitrogen is challenging using conventional Lewis acid-promoted pathways owing to competitive coordination of the amine to the Lewis acid promoter. Additionally, because many aminoglycosides lack a C2 substituent, diastereomeric mixtures of -glycosides are often produced. Herein, we present a method for the synthesis of α- or β- 2,3,6-trideoxy-3-amino- and 2,4,6-trideoxy-4-amino -glycosides from a common precursor.
View Article and Find Full Text PDFBackground: Despite clear clinical benefits, there is limited evidence regarding possible complications of the novel mechanical support device Impella. Aortic and mitral valve regurgitation or injury are rare but potential complications following implantation of the Impella device.
Methods: To evaluate valvular complications after the Impella device implantation, we have performed a comprehensive search of literature on multiple sites on this topic.
This paper aims to explore the trends in the research design used for assessing important quality cues in the meat industry and determine the most important quality cues that consumers use in their purchasing decisions. A Journal Article Network Analysis and non-parametric comparative analyses were used to collate the studies and analyse their findings respectively. Results indicate a predominate use of point-of-purchase surveys to collect data and consumers' stated preference to evaluate the important quality cues.
View Article and Find Full Text PDFIn this case report, we describe the successful application of veno-arterial extracorporeal membrane oxygenation support in a young patient with severe aortic regurgitation caused by a blocked mechanical valve. In this situation, extracorporeal membrane oxygenation mechanical support was used as a bridge to the prompt replacement of the diseased valve. Aortic regurgitation is commonly recognized as a contraindication to extracorporeal membrane oxygenation support because of the risk of ventricular distension, pulmonary oedema and further organ failure.
View Article and Find Full Text PDFPurpose: Porcine acellular dermal matrix (PADM) has been promoted as a suitable material for the reinforcement of the abdominal wall in Ventral Hernia Working Group (VHWG) Grade 3/4 wounds by Ventral Hernia Working Group et al. (Surgery 148(3):544-548). We describe our experience of, and assess the mechanisms for the failure of PADM (Permacol) in intestinal and abdominal wall reconstruction (AWR) for enterocutaneous fistulation (ECF).
View Article and Find Full Text PDFThe frailty syndrome is defined as a decrease in physiological reserve across multiple organ systems leading to increased vulnerability to external stressors. Studies across surgical subspecialties and in emergency and elective settings have identified frailty as an independent predictor of adverse postoperative clinician-reported, patient-reported and process-related outcomes. Although frailty is not specific to the older population, it is associated with ageing and therefore is increasingly observed in the ageing surgical population.
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