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Fusicoccadiene synthase from Phomopsis amygdala (PaFS) is a bifunctional terpene synthase. It contains a prenyltransferase (PT) domain that generates geranylgeranyl diphosphate (GGPP) from dimethylallyl diphosphate and three equivalents of isopentenyl diphosphate, and a cyclase domain that converts GGPP into fusicoccadiene, a precursor of the diterpene glycoside Fusicoccin A. The two catalytic domains are connected by a flexible 69-residue linker. The PT domain mediates oligomerization to form predominantly octamers, with cyclase domains randomly splayed out around the PT core. Surprisingly, despite the random positioning of cyclase domains, substrate channeling is operative in catalysis since most of the GGPP generated by the PT remains on the enzyme for cyclization. Here, we demonstrate that covalent linkage of the PT and cyclase domains is not required for GGPP channeling, although covalent linkage may improve channeling efficiency. Moreover, GGPP competition experiments with other diterpene cyclases indicate that the PaFS PT and cyclase domains are preferential partners regardless of whether they are covalently linked or not. The cryoelectron microscopy structure of the 600-kD "linkerless" construct, in which the 69-residue linker is spliced out and replaced with the tripeptide PTQ, reveals that cyclase pairs associate with all four sides of the PT octamer and exhibit fascinating quaternary structural flexibility. These results suggest that optimal substrate channeling is achieved when a cyclase domain associates with the side of the PT octamer, regardless of whether the two domains are covalently linked and regardless of whether this interaction is transient or locked in place. [ABSTRACT FROM AUTHOR]

Physicians incompletely record the secondary diagnoses and accompanying illnesses (comorbidities) of hospital patients. Among 162,790 patients 65 years or older who were admitted to California hospitals for a stroke, pneumonia, a heart attack or congestive heart failure, the average number of diagnoses recorded was 5.5 on hospital discharge forms that can hold 25 diagnostic codes. Patients with secondary diagnoses such as cardiac arrest, irregular heart beat, congestive heart failure, pneumonia and respiratory failure had a higher risk of dying in the hospital. Patients with secondary diagnoses of diabetes, hypertension, previous heart attack, chest pain and premature heart beats had a lower risk of dying in the hospital. These conditions normally would be expected to increase the risk of death, but are considered inappropriate comorbidities to certain conditions by Medicare. Physicians may record more secondary diagnoses in the medical records of patients who die than in those of patients who survive. Increasing the number of fields on discharge forms may not ensure more complete medical records.

Aim. To determine activities and outcomes of intensive care unit Liaison Nurse/Outreach services. The review comprised two stages: (1) integrative review of qualitative and quantitative studies examining intensive care liaison/outreach services in the UK and Australia and (2) meta-synthesis using the Nursing Role Effectiveness Model as an a priori model. Background. Acute ward patients are at risk of adverse events and patients recovering from critical illness are vulnerable to deterioration. Proactive and reactive strategies have been implemented to facilitate timely identification of patients at risk. Design. Systematic review. Methods. A range of data bases was searched from 2000--2008. Studies were eligible for review if they included adults in any setting where intensive care unit Liaison Nurse or Outreach services were provided. From 1423 citations and 65 abstracts, 20 studies met the inclusion criteria. Results. Intensive care liaison/outreach services had a beneficial impact on intensive care mortality, hospital mortality, unplanned intensive care admissions/re-admissions, discharge delay and rates of adverse events. A range of research methods were used; however, it was not possible to conclude unequivocally that the intensive care liaison/outreach service had resulted in improved outcomes. The major unmeasured benefit across all studies was improved communication pathways between critical care and ward staff. Outcomes for nurses in the form of improved confidence, knowledge and critical care skills were identified in qualitative studies but not measured. Conclusion. The varied nature of the intensive care liaison/outreach services reviewed in these studies suggests that they should be treated as bundled interventions, delivering a treatment package of care. Further studies should examine the impact of critical care support on the confidence and skills of ward nurses. Relevance to clinical practice. Advanced nursing roles can improve outcomes for patients who are vulnerable to deterioration. The Nursing Role Effectiveness Model provides a useful framework for evaluating the impact of these roles. [ABSTRACT FROM AUTHOR]

Prenyltransferases are terpene synthases that combine 5-carbon precursor molecules into linear isoprenoids of varying length that serve as substrates for terpene cyclases, enzymes that catalyze fascinating cyclization reactions to form diverse terpene natural products. Terpenes and their derivatives comprise the largest class of natural products and have myriad functions in nature and diverse commercial uses. An emerging class of bifunctional terpene synthases contains both prenyltransferase and cyclase domains connected by a disordered linker in a single polypeptide chain. Fusicoccadiene synthase from Phomopsis amygdali (PaFS) is one of the most well-characterized members of this subclass and serves as a model system for the exploration of structure-function relationships. PaFS has been structurally characterized using a variety of biophysical techniques. The enzyme oligomerizes to form a stable core of six or eight prenyltransferase domains that produce a 20-carbon linear isoprenoid, geranylgeranyl diphosphate (GGPP), which then transits to the cyclase domains for the generation of fusicoccadiene. Cyclase domains are in dynamic equilibrium between randomly splayed-out and prenyltransferase-associated positions; cluster channeling is implicated for GGPP transit from the prenyltransferase core to the cyclase domains. In this chapter, we outline the methods we are developing to interrogate the nature of cluster channeling in PaFS, including enzyme activity and product analysis assays, approaches for engineering the linker segment connecting the prenyltransferase and cyclase domains, and structural analysis by cryo-EM., (Copyright © 2024. Published by Elsevier Inc.)

Background: In intensive care observational studies, hypercapnia after cardiac arrest (CA) is independently associated with improved neurological outcome. However, the safety and feasibility of delivering targeted therapeutic mild hypercapnia (TTMH) for such patients is untested., Methods: In a phase II safety and feasibility multi-centre, randomised controlled trial, we allocated ICU patients after CA to 24h of targeted normocapnia (TN) (PaCO2 35-45mmHg) or TTMH (PaCO2 50-55mmHg). The primary outcome was serum neuron specific enolase (NSE) and S100b protein concentrations over the first 72h assessed in the first 50 patients surviving to day three. Secondary end-points included global measure of function assessment at six months and mortality for all patients., Results: We enrolled 86 patients. Their median age was 61 years (58, 64 years) and 66 (79%) were male. Of these, 50 patients (58%) survived to day three for full biomarker assessment. NSE concentrations increased in the TTMH group (p=0.02) and TN group (p=0.005) over time, with the increase being significantly more pronounced in the TN group (p(interaction)=0.04). S100b concentrations decreased over time in the TTMH group (p<0.001) but not in the TN group (p=0.68). However, the S100b change over time did not differ between the groups (p(interaction)=0.23). At six months, 23 (59%) TTMH patients had good functional recovery compared with 18 (46%) TN patients. Hospital mortality occurred in 11 (26%) TTMH patients and 15 (37%) TN patients (p=0.31)., Conclusions: In CA patients admitted to the ICU, TTMH was feasible, appeared safe and attenuated the release of NSE compared with TN. These findings justify further investigation of this novel treatment., (Copyright © 2016. Published by Elsevier Ireland Ltd.)

Objective: Trials in critical care have previously used unvalidated systems to classify cause of death. We aimed to provide initial validation of a method to classify cause of death in intensive care unit patients., Design, Setting and Participants: One hundred case scenarios of patients who died in an ICU were presented online to raters, who were asked to select a proximate and an underlying cause of death for each, using the ICU Deaths Classification and Reason (ICU-DECLARE) system. We evaluated two methods of categorising proximate cause of death (designated Lists A and B) and one method of categorising underlying cause of death. Raters were ICU specialists and research coordinators from Australia, New Zealand and the United Kingdom., Main Outcome Measures: Inter-rater reliability, as measured by the Fleiss multirater kappa, and the median proportion of raters choosing the most likely diagnosis (defined as the most popular classification choice in each case)., Results: Across all raters and cases, for proximate cause of death List A, kappa was 0.54 (95% CI, 0.49-0.60), and for proximate cause of death List B, kappa was 0.58 (95% CI, 0.53-0.63). For the underlying cause of death, kappa was 0.48 (95% CI, 0.44-0.53). The median proportion of raters choosing the most likely diagnosis for proximate cause of death, List A, was 77.5% (interquartile range [IQR], 60.0%-93.8%), and the median proportion choosing the most likely diagnosis for proximate cause of death, List B, was 82.5% (IQR, 60.0%-92.5%). The median proportion choosing the most likely diagnosis for underlying cause was 65.0% (IQR, 50.0%-81.3%). Kappa and median agreement were similar between countries. ICU specialists showed higher kappa and median agreement than research coordinators., Conclusions: The ICU-DECLARE system allowed ICU doctors to classify the proximate cause of death of patients who died in the ICU with substantial reliability.

Background: The Intensive Care Unit (ICU) Liaison Nurses (LNs) emerged as a member of the multidisciplinary team to: assist in the transition of patients from ICU to the ward, respond to the deteriorating patient in an appropriate and timely manner, and in some instances act as an integral member of Rapid Response Teams (RRT)., Purpose: To identify the common core aspects and diversity within the ICU LN role across Australia and to determine whether the ICU LN hours of operation and the participation in MET teams has any impact on the activities undertaken by the ICU LN., Method: This descriptive survey of 152 Australian ICUs was conducted in April 2010. The Advanced Practice Nurse (APN) framework was used to develop the survey instrument, which comprised of four scales, education (5 items), collaboration (6 items), practice (8 items) research and quality (6 items) and a number of demographic questions. Descriptive statistics (mean, standard deviation (SD), median, interquartile ranges (IQR) and frequency) were used to summarise the data. Student's t-tests and Pearson's correlations were used to test the hypotheses., Results: Surveys were received from 113 hospitals (55 metropolitan, 58 regional): a 74% response rate. ICU LN services operated in 31 (27%) of these hospitals. LN services tended to operate in larger hospitals with higher ICU admission rates. The median weekly hours of operation was 56 (IQR 30; range 7-157), delivered by a median of 1.4 (IQR 0.9; range 0.0-4.2) Full Time Equivalent (FTE) staff. The median weekly patient visits made by the LN was 25 (IQR 44; range 2-145). The LN was reported to be a member of the Medical Emergency Team (MET) in 17 (68%) of the 25 hospitals that provided both MET and ICU LN services. The ICU LN activities were grouped under four key Advanced Practice Nurse (APN) domains: education, collaboration, practice and research/quality. Mean scale scores were calculated for each APN domain. The ICU LN reported being involved in activities associated with all four APN domains, and more frequently they were involved in education and expert practice during their daily work. Neither the presence of a MET nor the weekly operational hours of the LN service significantly affected the key activities undertaken by ICU LNs (education, collaboration, practice, research and quality)., Conclusion: Whilst many hospitals across Australia have introduced an ICU LN service, the staffing, hours of service, job classifications, reporting lines, referral processes and APN activities undertaken by the ICU LN, vary between hospitals, highlighting the diverse nature of ICU LN services across Australia., (Copyright © 2012 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.)

Unlabelled: Delirium is an acute, reversible and fluctuating central nervous system dysfunction with an organic cause, and is associated with substantial morbidity and mortality. Many recent studies have shown that delirium is highly prevalent in the Intensive Care Unit (ICU) population. Despite its seriousness; delirium in the ICU is under recognized by bedside nurses., Objective: To determine if routine bedside nurse-patient interactions enable the detection of delirium., Method: We performed a single center observational study, in a 12 bed general Intensive Care Unit. Bedside nurses were asked to assess patients for delirium during routine patient care throughout their shift. This assessment was then compared to an independent assessment using the Confusion Assessment Method - ICU (CAM-ICU) performed by a nurse trained in this delirium detection tool., Results: We analysed the results of 35 matched assessments performed on 35 patients. The presence of delirium was identified by the bedside nurse in 27% of CAM-ICU delirium positive assessments, whereas the absence of delirium was identified by the bedside nurse in 92% of CAM-ICU delirium negative assessments., Conclusion: There was a significant discrepancy between the ICU bedside nurses' assessment of delirium and the independent formal delirium assessment utilizing the CAM-ICU. We concluded that routine bedside nursing patient interaction do not reliably detect delirium in a critically ill patient., (Copyright © 2011 Australian College of Critical Care Nurses Ltd. All rights reserved.)

Time-lapse video light microscopy was used to study the emergence and maturation of the migratory slug from a D. discoideum aggregate. The anterior part, the tip of this simple multicellular organism, establishes migration prior to the definition of the rear, and hence the length of the slug. It was found that newly formed slugs of wild-type strain WS380B can reach lengths greater than 1 cm, yet mature slugs of this strain are rarely longer than 2-3 mumm. Often the tip extended out of the aggregation mound upon an arching pillar of cells. After the tip first touched the substratum, it commenced migration with a rapid succession of movement steps. Here we show that at the initiation of migration, a differential rate of cell movement along the developing slug axis results in a series of complicated changes, before the stable and mature shape of the slug is formed. Our results lead to new conclusions about D. discoideum slug formation and shape maintenance. Evidence is presented for regulation of slug length.