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Background: Ex vivo assays of platelet function critically inform mechanistic and clinical hematology studies, where effects of divergent blood processing methods on platelet composition are apparent, but unspecified., Objective: Here, we evaluate how different blood anticoagulation options and processing times affect platelet function and protein content ex vivo., Methods: Parallel blood samples were collected from healthy human donors into sodium citrate, acid citrate dextrose, EDTA or heparin, and processed over an extended time course for functional and biochemical experiments, including platelet proteome quantification with multiplexed tandem mass tag (TMT) labeling and triple quadrupole mass spectrometry (MS)., Results: Each anticoagulant had time-dependent effects on platelet function in whole blood. For instance, heparin enhanced platelet agonist reactivity, platelet-monocyte aggregate formation and platelet extracellular vesicle release, while EDTA increased platelet α-granule secretion. Following platelet isolation, TMT-MS quantified 3357 proteins amongst all prepared platelet samples. Altogether, >400 proteins were differentially abundant in platelets isolated from blood processed at 24 h versus 1 h post-phlebotomy, including proteins pertinent to membrane trafficking and exocytosis. Anticoagulant-specific effects on platelet proteomes included increased complement system and decreased α-granule proteins in platelets from EDTA-anticoagulated blood. Platelets prepared from heparinized blood had higher levels of histone and neutrophil-associated proteins in a manner related to neutrophil extracellular trap (NET) formation and platelet:NET interactions in whole blood ex vivo., Conclusion: Our results demonstrate that different anticoagulants routinely used for blood collection have varying effects on platelets ex vivo, where methodology-associated alterations in platelet proteome may influence mechanistic, translational and biomarker studies., (© 2022 International Society on Thrombosis and Haemostasis.)

Maar-diatreme volcanoes are the second-most common type on land, occurring in volcanic fields within all major tectonic environments. Their deposits typically contain an abundance of lithic fragments quarried from the substrate, and many contain large, deep-sourced lithic fragments that were erupted to the surface. Primary volcaniclastic deposits fill the diatreme structure formed during eruption. There is negligible inelastic deformation of diatreme-adjacent country rock, indicating that country rock is removed to create the diatreme structures, either by being shifting downward below observable levels, ejected upward to contribute to surficial deposits, or dissolved and hidden in magma erupted or intruded at depth. No previous study has systematically reviewed and analysed the reported lithic fragments of maar-diatreme systems. We present a comprehensive compilation from published work of lithic characteristics in maar ejecta rings and in diatreme deposits of both common and kimberlite maar-diatremes. For maar-diatremes and their tephra ring deposits, we find no correlations among lithic clast sizes, shapes, depositional sites, and excavation depths. This is difficult to reconcile with models involving systematic diatreme deepening coupled with tephra-ring growth, but consistent with those involving chaotic explosions and mixing. Larger amounts of data are needed to further examine how these types of volcanoes operate., (© 2021. The Author(s).)

Aim: To determine feasibility and acceptability of completing PROs questionnaires at completion and 1 year after curative cancer treatment., Methods: Patients assessed in a nurse-led end of treatment survivorship clinic, at a tertiary referral centre, recruited between October 2015 and July 2016 were mailed a survey at baseline and at 12-month follow-up. The survey included validated PRO questionnaires. A target response rate for feasibility, defined as the proportion of the eligible population approached that completed the survey, was set at 70%. Qualitative feedback regarding the survey was collected from participants., Results: Of the 47 eligible patients approached, 34 (72.4%) agreed to participate with 29 (61.9%) completing the survey at baseline, and 21 (44.7%) at follow-up. Respondents lost to follow-up at 12 months had clinically meaningful lower scores on all QLQ-C30 functioning scales and 8 out of 9 symptom scales/items. Qualitative feedback from survey respondents indicated the content was relevant and acceptable. Participants expressed willingness to complete a similar survey approximately once per year and a higher preference for completing the survey in hard copy compared with online., Conclusions: Cancer survivors are willing to provide information on a range of PROs, but those with higher needs were the ones less likely to complete surveys. There is scope to improve the response rate and representativeness of the patient cohort captured. Future research should identify strategies to optimise recruitment when collecting PROs data from cancer survivors.

Survivorship treatment summaries and care plans are increasingly incorporated into cancer care but there are limited data on their accuracy and acceptability. We have evaluated written care plans developed as part of a once-off, nurse-led survivorship consultations across four medical oncology clinics in South Australia as part of a state-wide pilot. While the accuracy of treatment summaries was high, level of detail in care plans was moderate to low, as was survivors' perception of plans' utility., (© 2020 Royal Australasian College of Physicians.)

Background: The rising incidence of acetabular fractures in the elderly presents an increasing surgical challenge due to patient co-morbidities, complex fracture patterns' and osteoporotic bone. Of interest in this study are those of the quadrilateral plate, which are more common in elderly patients with osteoporosis. Following such injuries, the weight-bearing surface of the femoral head moves medially. Non-operative management of these fractures can lead to the acetabulum articulating on the femoral neck increasing the risk of subsequent femoral neck fracture as a result of the altered biomechanics.Using finite element analysis (FEA) this study seeks to understand the changing biomechanics of the proximal femur in such instances and to determine if there is a threshold of femoral head medialisation that can predict probability of femoral neck fracture., Methods: A femoral neck FEA model was created from the CT and MRI scans of a healthy hip. Using FEA, the model was used to apply point loading to the femoral head at the anatomical weight bearing area and subsequent lateralization of this point down to the femoral neck-shaft junction. This simulates the changing forces acting on the femur as the head medialises into a fractured acetabulum., Results: As the point of contact moved laterally the stress levels within the proximal femur increased steadily, particularly along the superior neck. Bending moment at the medial neck shaft junction also increased. This increase in stress levels can be seen as a corollary for risk of fracture within the femur., Conclusion: With medialisation of the femur into a fractured acetabulum there is a significant change in the stress distribution within the femoral neck. Clinically, this is indicates that patients with such injuries are at an increased risk of femoral neck fractures once they begin to mobilise after the initial injury, a devastating result. This model may be of use to treating surgeons in predicting the risk of femoral neck fracture., (© 2019 Prof. PK Surendran Memorial Education Foundation. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.)

In cocaine use disorder, relapse can be elicited by drug-associated cues despite long periods of abstinence. The persistence of drug-associated cues in eliciting drug seeking suggests enduring changes in structural and functional plasticity, which may be mediated by basic fibroblast growth factor (bFGF, FGF2). Stimulant drug use increases bFGF expression in reward- and learning-related brain regions, such as the infralimbic medial-prefrontal cortex (IL-mPFC), and we previously found that this increase was reversed by extinction. However, whether bFGF expression is similarly modified in other brain regions is unknown. Therefore, we used the conditioned place preference (CPP) paradigm to assess bFGF expression following cocaine-associated CPP or extinction of that CPP within the mPFC, nucleus accumbens (NAc), hippocampus (Hipp), and basolateral amygdala (BLA). bFGF expression was increased in IL-mPFC and NAc-Core and -Shell following a cocaine-associated CPP, an effect reversed by extinction. Conversely, bFGF expression was increased in BLA following extinction, but no significant changes were observed in PL-mPFC or either dorsal or ventral Hipp. These results demonstrate differential regulation of bFGF following cocaine-associated CPP or extinction of that CPP in discrete brain regions. Changes in bFGF expression may regulate long-lasting drug-induced plasticity that underlies persistent drug-associated memories, and therefore present potential prophylactic targets., (© 2018 Doncheck et al.; Published by Cold Spring Harbor Laboratory Press.)

Presentation of drug-associated cues provokes craving and drug seeking, and elimination of these associative memories would facilitate recovery from addiction. Emotionally salient memories are maintained during retrieval, as particular pharmacologic or optogenetic perturbations of memory circuits during retrieval, but not after, can induce long-lasting memory impairments. For example, in rats, inhibition of noradrenergic beta-receptors, which control intrinsic neuronal excitability, in the prelimbic medial prefrontal cortex (PL-mPFC) can cause long-term memory impairments that prevent subsequent cocaine-induced reinstatement. The physiologic mechanisms that allow noradrenergic signaling to maintain drug-associated memories during retrieval, however, are unclear. Here we combine patch-clamp electrophysiology ex vivo and behavioral neuropharmacology in vivo to evaluate the mechanisms that maintain drug-associated memory during retrieval in rats. Consistent with previous studies, we find that cocaine experience increases the intrinsic excitability of pyramidal neurons in PL-mPFC. In addition, we now find that this intrinsic plasticity positively predicts the retrieval of a cocaine-induced conditioned place preference (CPP) memory, suggesting that such plasticity may contribute to drug-associated memory retrieval. In further support of this, we find that pharmacological blockade of a cAMP-dependent signaling cascade, which allows noradrenergic signaling to elevate neuronal excitability, is required for memory maintenance during retrieval. Thus, inhibition of PL-mPFC neuronal excitability during memory retrieval not only leads to long-term deficits in the memory, but this memory deficit provides protection against subsequent cocaine-induced reinstatement. These data reveal that PL-mPFC intrinsic neuronal excitability maintains a cocaine-associated memory during retrieval and suggest a unique mechanism whereby drug-associated memories could be targeted for elimination.

Patient outcomes for retroperitoneal laparoscopic radical nephrectomy (RLRN) in adults on peritoneal dialysis (PD) have not been described in the literature. This is the first series on the successful application of RLRN for renal cell carcinoma (RCC) among adults with end-stage renal disease (ESRD) on PD. In our series of 5 patients, all were able to promptly resume PD, no wound complications were noted at postoperative visits, and no evidence of recurrence was identified on surveillance imaging at follow-up. We propose that RLRN should be considered in PD patients as it allows immediate reinstitution of PD and prevents the morbidity and complications associated with interim hemodialysis., (Copyright © 2017 International Society for Peritoneal Dialysis.)

Drug seeking is maintained by encounters with drug-associated cues, and disrupting retrieval of these drug-cue associations would reduce the risk of relapse. Retrieval of cocaine-associated memories is dependent on β-adrenergic receptor (β-AR) activation, and blockade of these receptors induces a persistent retrieval deficit. Whether retrieval of cocaine-associated memory is mediated by a specific β-AR subtype, however, remains unclear. Using a cocaine conditioned place preference (CPP) procedure, we examined whether retrieval of a cocaine CPP memory is mediated collectively by β1- and β2-ARs, or by one of these β-AR subtypes alone. We show that co-blockade of β1- and β2-ARs abolished CPP expression on that and subsequent drug-free CPP tests, resulting in a long-lasting retrieval deficit that prevented subsequent cocaine-induced reinstatement. To dissociate the necessity of either β1- or β2-ARs alone, we administered subtype-specific antagonists prior to retrieval. Administration of a β1-AR antagonist before the initial CPP trial dose-dependently reduced expression of a CPP on that and subsequent drug-free trials as compared to vehicle administration. In contrast, administration of a β2-AR antagonist had no effect on initial CPP expression, although the highest dose reduced subsequent CPP expression. Importantly, either β1- or β2-AR blockade prior to an initial retrieval trial prevented subsequent cocaine-induced reinstatement. Our findings indicate that the β1-AR subtype mediates retrieval of a cocaine CPP, and that acutely blocking either β1- or β2-ARs can prevent subsequent cocaine-induced reinstatement. Thus, β-AR antagonists, particularly β1-ARs antagonists, could serve as adjuncts for addiction therapies to prevent retrieval of drug-associated memories and provide protection against relapse., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Brain-derived neurotrophic factor (BDNF) regulates synaptic activity and behavioral flexibility, and reduction of BDNF strongly predicts psychiatric disorders and cognitive dysfunction. Restoration of BDNF-dependent activity could alleviate these impairments, but BDNF has limited clinical utility due to its pharmacokinetics. Here we demonstrate that activation of a primary BDNF target, the tropomyosin-related kinase B (TrkB) receptor, enhances the amplitude and prolongs the decay kinetics of N-methyl-d-aspartate receptor (NMDAR) currents in male rat infralimbic prefrontal pyramidal neurons. Moreover, these effects were prevented and reversed by blockade of NMDARs containing the GluN2B subunit. Our results show that this signaling cascade bidirectionally regulates extinction of a cocaine-induced conditioned place preference (CPP), a task that requires behavioral flexibility. Blockade of infralimbic TrkB receptors or GluN2B-containing NMDARs disrupted consolidation of extinction of the CPP. In contrast, extinction was strengthened by potentiation of TrkB receptor activity with infralimbic infusions of BDNF or systemic injections of 7,8 dihydroxyflavone (7,8DHF), the newly synthesized TrkB receptor agonist. The 7,8DHF-induced enhancement of extinction was prevented by infralimbic infusions of a GluN2B-specific receptor antagonist, demonstrating that TrkB receptor activation enhances extinction of cocaine-CPP via GluN2B-containing NMDARs. Together, infralimbic TrkB receptor activation strengthens GluN2B-containing NMDAR currents to support extinction learning. TrkB receptor agonists would therefore be useful as pharmacological adjuncts for extinction-based therapies for treatment of psychiatric disorders associated with reduced BDNF activity.

Retrieval of drug-associated memories is critical for maintaining addictive behaviors, as presentation of drug-associated cues can elicit drug seeking and relapse. Recently, we and others have demonstrated that β-adrenergic receptor (β-AR) activation is necessary for retrieval using both rat and human memory models. Importantly, blocking retrieval with β-AR antagonists persistently impairs retrieval and provides protection against subsequent reinstatement. However, the neural locus at which β-ARs are required for maintaining retrieval and subsequent reinstatement is unclear. Here, we investigated the necessity of dorsal hippocampus (dHipp) β-ARs for drug-associated memory retrieval. Using a cocaine conditioned place preference (CPP) model, we demonstrate that local dHipp β-AR blockade before a CPP test prevents CPP expression shortly and long after treatment, indicating that dHipp β-AR blockade induces a memory retrieval disruption. Furthermore, this retrieval disruption provides long-lasting protection against cocaine-induced reinstatement. The effects of β-AR blockade were dependent on memory reactivation and were not attributable to reconsolidation disruption as blockade of β-ARs immediately after a CPP test had little effect on subsequent CPP expression. Thus, cocaine-associated memory retrieval is mediated by β-AR activity within the dHipp, and disruption of this activity could prevent cue-induced drug seeking and relapse long after treatment.

The reaction of 70 unprotected, diversely functionalized free reducing sugars with methoxyamine-appended colchicine led to the production of a 58-member glycorandomized library. High-throughput cytotoxicity assays revealed glycosylation to modulate specificity and potency. Library members were also identified which, unlike the parent natural product (a destabilizer), stabilized in vitro tubulin polymerization in a manner similar to taxol. This study highlights a simple extension of neoglycorandomization toward amine-bearing scaffolds and the potential benefit of glycosylating nonglycosylated natural products.