Limited Metabolomic Overlap between Commensal Bacteria and Marine Sponge Holobionts Revealed by Large Scale Culturing and Mass Spectrometry-Based Metabolomics: An Undergraduate Laboratory Pedagogical Effort at Georgia Tech.

Sponges are the richest source of bioactive organic small molecules, referred to as natural products, in the marine environment. It is well established that laboratory culturing-resistant symbiotic bacteria residing within the eukaryotic sponge host matrix often synthesize the natural products that are detected in the sponge tissue extracts. However, the contributions of the culturing-amenable commensal bacteria that are also associated with the sponge host to the overall metabolome of the sponge holobiont are not well defined. In this study, we cultured a large library of bacteria from three marine sponges commonly found in the Florida Keys. Metabolomes of isolated bacterial strains and that of the sponge holobiont were compared using mass spectrometry to reveal minimal metabolomic overlap between commensal bacteria and the sponge hosts. We also find that the phylogenetic overlap between cultured commensal bacteria and that of the sponge microbiome is minimal. Despite these observations, the commensal bacteria were found to be a rich resource for novel natural product discovery. Mass spectrometry-based metabolomics provided structural insights into these cryptic natural products. Pedagogic innovation in the form of laboratory curricula development is described which provided undergraduate students with hands-on instruction in microbiology and natural product discovery using metabolomic data mining strategies.

Reducing Medical Admissions and Presentations Into Hospital through Optimising Medicines (REMAIN HOME): a stepped wedge, cluster randomised controlled trial.

OBJECTIVE: To investigate whether integrating pharmacists into general practices reduces the number of unplanned re-admissions of patients recently discharged from hospital. DESIGN, SETTING: Stepped wedge, cluster randomised trial in 14 general practices in southeast Queensland. PARTICIPANTS: Adults discharged from one of seven study hospitals during the seven days preceding recruitment (22 May 2017 - 14 March 2018) and prescribed five or more long term medicines, or having a primary discharge diagnosis of congestive heart failure or exacerbation of chronic obstructive pulmonary disease. INTERVENTION: Comprehensive face-to-face medicine management consultation with an integrated practice pharmacist within seven days of discharge, followed by a consultation with their general practitioner and further pharmacist consultations as needed. MAJOR OUTCOMES: Rates of unplanned, all-cause hospital re-admissions and emergency department (ED) presentations 12 months after hospital discharge; incremental net difference in overall costs. RESULTS: By 12 months, there had been 282 re-admissions among 177 control patients (incidence rate [IR], 1.65 per person-year) and 136 among 129 intervention patients (IR, 1.09 per person-year; fully adjusted IR ratio [IRR], 0.79; 95% CI, 0.52-1.18). ED presentation incidence (fully adjusted IRR, 0.46; 95% CI, 0.22-0.94) and combined re-admission and ED presentation incidence (fully adjusted IRR, 0.69; 95% CI, 0.48-0.99) were significantly lower for intervention patients. The estimated incremental net cost benefit of the intervention was $5072 per patient, with a benefit-cost ratio of 31:1. CONCLUSION: A collaborative pharmacist-GP model of post-hospital discharge medicines management can reduce the incidence of hospital re-admissions and ED presentations, achieving substantial cost savings to the health system. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12616001627448 (prospective).

Medication use and cognitive impairment among residents of aged care facilities.

BACKGROUND: Potentially inappropriate polypharmacy is common in residential aged care facilities (RACF). This is of particular concern among people with cognitive impairment who, compared with cognitively intact residents, are potentially more sensitive to the adverse effects of medications. AIM: To compare the patterns of medication prescribing of RACF residents based on cognitive status. METHODS: De-identified data collected during telehealth-mediated geriatric consultations with 720 permanent RACF residents were analysed. Residents were categorised into cognitively intact, mild to moderate impairment and severe impairment groups using the interRAI Cognitive Performance Scale. The number of all regular and when-required medications used in the past 3 days, the level of exposure to anti-cholinergic/sedative medications and potentially inappropriate medications and the use of preventive and symptom control medications were compared across the groups. RESULTS: The median number of medications was 10 (interquartile range (IQR) 8-14). Cognitively intact residents were receiving significantly more medications (median (IQR) 13 (10-16)) than those with mild to moderate (10 (7-13)) or severe (9 (7-12)) cognitive impairment (P < 0.001). Overall, 82% of residents received at least one anti-cholinergic/sedative medication and 26.9% were exposed to one or more potentially inappropriate medications, although the proportions of those receiving such medications were not significantly different across the groups. Of 7658 medications residents were taking daily, 21.3% and 11.7% were classified as symptom control and preventive medications respectively with no significant difference among the groups in their use. CONCLUSION: Our findings highlight the need for optimising prescribing in RACF residents, with particular attention to medications with anti-cholinergic effects.

Cytogenetic analysis of 130 renal oncocytomas identify three distinct and mutually exclusive diagnostic classes of chromosome aberrations.

The cytogenetic alterations in renal oncocytoma (RO) are poorly understood. We analyzed 130 consecutive RO for karyotypic alterations. Clonal chromosome abnormalities were identified in 63 (49%) cases, which could be categorized into three classes of mutually exclusive cytogenetic categories. Class 1 (N = 20) RO had diploid karyotypes with characteristic 11q13 rearrangement in balanced translocations with 10 or more different chromosome partners in all cases. We identified recurrent translocation partners at 5q35, 6p21, 9p24, 11p13-14, and 11q23, and confirmed that CCND1 gene rearrangement at 11q13 utilizing fluorescence in situ hybridization (FISH). Class 2 RO (N = 25) exhibited hypodiploid karyotypes with loss of chromosome 1 and/or losses of Y in males and X in females in all cases. The class 3 tumors comprising of 18 cases showed diverse types of abnormalities with the involvement of two or more chromosomes exclusive of abnormalities seen in classes 1 and 2 tumors. Furthermore, karyotypically uninformative cases were subjected to FISH analysis to identify classes 1 and 2 abnormalities. In this group, we found similar frequencies of CCND1 rearrangement, loss of chromosome 1 or Y as with karyotypically abnormal cases. We validated our results against 91 tumors from the Mitelman database. Correlation of clinical data with all the three classes of ROs showed no clear evidence of overall patient survival. Our findings support the hypothesis that RO exhibit three principal cytogenetic categories, which may have different roles in initiation and/or progression. These cytogenetic markers provide a key tool in the diagnostic evaluation of RO.

Community pharmacy staff needs for the provision of oral health care education and advice in Australia.

BACKGROUND: In Australia, 61% of pharmacy staff (pharmacists and pharmacy assistants) state that on average they are consulted for oral health care advice 2 or more times each week. International studies recognize the potential to enhance pharmacy staff roles in oral health care, given they are regularly consulted for a variety of oral health issues. OBJECTIVES: This study explored the preparedness of pharmacy staff to provide oral health care education and advice within Australian community pharmacies. The aims of this study were (1) to assess the types of oral health education resources available for pharmacy staff and patients within Australian community pharmacies; (2) determine pharmacy staff awareness of available Australian government-funded dental services or schemes and; (3) explore pharmacy staff views regarding safety of drinking water fluoridation in Australia. METHODS: Pharmacists and pharmacy assistants from a randomly selected national sample of 5700 Australian community pharmacies were invited to complete an online or postal questionnaire. Participants were offered a A$10 incentive to enhance response rates. Descriptive and analytical statistics were used for the analysis. RESULTS: The response rate for the pharmacist cohort was 58.5% (644 of 1100) and 28% (280 of 1000) for pharmacy assistants. More than 80% of pharmacy staff did not have oral health education resources for patients and did not have access to oral health information resources for their own education. Nearly all staff (96%) were unaware of government Child Dental Benefits Schedule (CDBS) and Department of Veterans' Affairs dental funding support. Approximately one-third of pharmacy staff believed that water fluoridation in drinking water supplies was unsafe or were unsure of its safety. CONCLUSIONS: Oral health care training and education resources are needed to support pharmacy staff to deliver improved and responsive oral health care within Australian communities.

Negotiating "Unmeasurable Harm and Benefit": Perspectives of General Practitioners and Consultant Pharmacists on Deprescribing in the Primary Care Setting.

The use of multiple medicines, known as polypharmacy, poses a risk of harm that is greatest in older adults with multimorbidity. Deprescribing aims to improve health outcomes through ceasing medicines that are no longer necessary or appropriate due to changing clinical circumstances and patient priorities. General practitioners (GPs) and consultant pharmacists (CPs) are well positioned to facilitate deprescribing in primary care in partnership with older adults who present with inappropriate polypharmacy. In this article, we explore GPs' and CPs' views about inappropriate polypharmacy, the reasoning they apply to deprescribing in primary care, and identify factors that support or inhibit this process. Using focus group methodology and the Framework Method for thematic analysis, two major themes were discerned from the data-working through uncertainty and risk perception as a frame of reference. The findings provide important insights when devising methods for advancing and supporting deprescribing in primary care.

Hepatocyte exosomes mediate liver repair and regeneration via sphingosine-1-phosphate.

BACKGROUND & AIMS: Exosomes are small membrane vesicles involved in intercellular communication. Hepatocytes are known to release exosomes, but little is known about their biological function. We sought to determine if exosomes derived from hepatocytes contribute to liver repair and regeneration after injury. METHODS: Exosomes derived from primary murine hepatocytes were isolated and characterized biochemically and biophysically. Using cultures of primary hepatocytes, we tested whether hepatocyte exosomes induced proliferation of hepatocytes in vitro. Using models of ischemia/reperfusion injury and partial hepatectomy, we evaluated whether hepatocyte exosomes promote hepatocyte proliferation and liver regeneration in vivo. RESULTS: Hepatocyte exosomes, but not exosomes from other liver cell types, induce dose-dependent hepatocyte proliferation in vitro and in vivo. Mechanistically, hepatocyte exosomes directly fuse with target hepatocytes and transfer neutral ceramidase and sphingosine kinase 2 (SK2) causing increased synthesis of sphingosine-1-phosphate (S1P) within target hepatocytes. Ablation of exosomal SK prevents the proliferative effect of exosomes. After ischemia/reperfusion injury, the number of circulating exosomes with proliferative effects increases. CONCLUSIONS: Our data shows that hepatocyte-derived exosomes deliver the synthetic machinery to form S1P in target hepatocytes resulting in cell proliferation and liver regeneration after ischemia/reperfusion injury or partial hepatectomy. These findings represent a potentially novel new contributing mechanism of liver regeneration and have important implications for new therapeutic approaches to acute and chronic liver disease.

Microdroplet-Based Potentiometric Redox Measurements on Gold Nanoporous Electrodes.

Potentiometric redox measurements were made in subnanoliter droplets of solutions using an optically transparent nanoporous gold electrode strategically mounted on the stage of an inverted microscope. Nanoporous gold was prepared via dealloying gold leaf with concentrated nitric acid and was chemisorbed to a standard microscope coverslip with (3-mercaptopropyl)trimethoxysilane. The gold surface was further modified with 1-hexanethiol to optimize hydrophobicity of the surface to allow for redox measurements to be made in nanoscopic volumes. Time traces of the open-circuit potential (OCP) were used to construct Nernst plots to evaluate the applicability of the droplet-based potentiometric redox measurement system. Two poised one-electron transfer systems (potassium ferricyanide/ferrocyanide and ferrous/ferric ammonium sulfate) yielded Nernstian slopes of -58.5 and -60.3 mV, respectively, with regression coefficients greater than 0.99. The y-intercepts of the two agreed well to the formal potential of the two standard oxidation-reduction potential (ORP) calibrants, ZoBell's and Light's solution. The benzoquinone and hydroquinone redox couple was examined as a representative two-electron redox system; a Nernst slope of -30.8 mV was obtained. Additionally, two unpoised systems (potassium ferricyanide and ascorbic acid) were studied to evaluate the system under conditions where only one form of the redox couple is present in appreciable concentrations. Again, slopes near the Nernstian values of -59 and -29 mV, respectively, were obtained. All experiments were carried out using solution volumes between 280 and 1400 pL with injection volumes between 8 and 100 pL. The miniscule volumes allowed for extremely rapid mixing (<305 ms) as well. The small volumes and rapid mixing along with the high accuracy and sensitivity of these measurements lend support to the use of this approach in applications where time is a factor and only small volumes are available for testing.

A multifaceted intervention to reduce inappropriate polypharmacy in primary care: research co-creation opportunities in a pilot study.

Co-creation (or co-design) represents the highest form of stakeholder engagement, but it can be infeasible to co-create with all stakeholders through all stages of a research project. The choice of stakeholders for co-design will depend on the study purpose and context of change. For this deprescribing pilot study, general practitioners were recognised as a critical gateway for co-creation, with patients' perspectives of the deprescribing process to be assessed in the evaluation of the pilot.

Influence of Water Table Depth on Pore Water Chemistry and Trihalomethane Formation Potential in Peatlands.

Drained peatland catchments are reported to produce more colored, dissolved organic carbon (DOC)-rich water, presenting problems for potable water treatment. The blocking of peatland drainage ditches to restore the water table is increasingly being considered as a strategy to address this deterioration in water quality. However, the effect of ditch blocking on the potential of DOC to form trihalomethanes (THMs) has not been assessed. In this study, the effect of peat rewetting on pore water DOC concentration and characteristics (including THM formation potential [THMFP]) was assessed over 12 months using peat cores collected from two drained peatland sites. The data show little evidence of differences in DOC concentration or characteristics between the different treatments. The absence of any difference in the THMFP of pore water between treatments suggests that, in the short term at least, ditch blocking may not have an effect on the THMFP of waters draining peatland catchments.

CXC chemokine receptor-4 signaling limits hepatocyte proliferation after hepatic ischemia-reperfusion in mice.

The role of stromal cell-derived factor-1 (SDF-1 or CXCL12) and its receptor CXC chemokine receptor-4 (CXCR4) in ischemic liver injury and recovery has not been studied. Some reports suggest that this chemokine may aid in liver regeneration, but others suggest that it may be profibrotic through its activation of hepatic stellate cells. In this study we sought to elucidate the role of SDF-1 and its receptor CXCR4 during liver injury, recovery, and regeneration after ischemia-reperfusion (I/R). A murine model of partial (70%) I/R was used to induce liver injury and study the reparative and regenerative response. CXCR4 was expressed constitutively in the liver, and hepatic levels of SDF-1 peaked 8 h after reperfusion but remained significantly increased for 96 h. Treatment of mice with the CXCR4 antagonist AMD3100 or agonist SDF-1 had no effect on acute liver injury assessed 8 h after I/R. However, treatment with AMD3100 increased hepatocyte proliferation after 72 and 96 h of reperfusion and reduced the amount of liver necrosis. In contrast, treatment with SDF-1 significantly decreased hepatocyte proliferation. These effects appeared to be dependent on the presence of liver injury, as AMD3100 and SDF-1 had no effect on hepatocyte proliferation or liver mass in mice undergoing 70% partial hepatectomy. The data suggest that signaling through CXCR4 is detrimental to liver recovery and regeneration after I/R and that clinical therapy with a CXCR4 antagonist may improve hepatic recovery following acute liver injury.

Sphingolipids in liver injury, repair and regeneration.

Sphingolipids are not only essential components of cellular membranes but also function as intracellular and extracellular mediators that regulate important physiological cellular processes including cell survival, proliferation, apoptosis, differentiation, migration and immune responses. The liver possesses the unique ability to regenerate after injury in a complex manner that involves numerous mediators, including sphingolipids such as ceramide and sphingosine 1-phosphate. Here we present the current understanding of the involvement of the sphingolipid pathway and the role this pathway plays in regulating liver injury, repair and regeneration. The regulation of sphingolipids and their enzymes may have a great impact in the development of novel therapeutic modalities for a variety of liver injuries and diseases.

Inhibition of acidic sphingomyelinase reduces established hepatic fibrosis in mice.

AIM: Liver fibrosis occurs as a result of several chronic liver diseases and leads to portal hypertension, cirrhosis and liver failure, often requiring liver transplantation. Activated hepatic stellate cells (HSC) are known to contribute to liver fibrosis, but currently there are no effective therapies for the treatment of established liver fibrosis. Activation of the acidic sphingomyelinase (ASM) has been shown to be involved in HSC activation. In the present study we investigated whether treatment with the ASM inhibitor, amitriptyline (TCA), could prevent and/or reverse fibrosis induced in mice by carbon tetrachloride (CCl4 ). METHODS: Mice were treated with CCl4 for 8 weeks to induce fibrosis. Concurrently, mice received drinking water with or without 180 mg/L TCA. RESULTS: Mice receiving TCA in the water had decreased hepatic collagen deposition and reduced liver mRNA expression of the fibrogenic mediators, transforming growth factor (TGF)-ß1, tissue inhibitor of matrix metalloproteinase-1, collagen and tumor necrosis factor-α. TCA treatment also reduced HSC activation determined by α-smooth muscle actin staining. In a separate set of experiments, mice were treated with CCl4 for 5 weeks prior to treatment with TCA, to test whether TCA had any effect on established fibrosis. Remarkably, in mice with established fibrosis, treatment with TCA significantly reduced collagen deposition, HSC activation, and prevented portal hypertension and improved hepatic architecture. Treatment of isolated HSC in vitro with TCA completely inhibited TGF-ß1-induced collagen expression and platelet-derived growth factor-ß-ß-induced proliferation. CONCLUSION: The data suggest that ASM is a critical signaling component in HSC for the development of liver fibrosis and represents an important therapeutic target.

First do no harm: a real need to deprescribe in older patients.

Inappropriate polypharmacy in older patients imposes a significant burden of decreased physical functioning, increased risk of falls, delirium and other geriatric syndromes, hospital admissions and death. The single most important predictor of inappropriate prescribing and risk of adverse drug events in older patients is the number of prescribed medications. Deprescribing is the process of tapering or stopping drugs, with the goal of minimising polypharmacy and improving outcomes. Barriers to deprescribing include underappreciation of the scale of polypharmacy-related harm by both patients and prescribers; multiple incentives to overprescribe; a narrow focus on lists of potentially inappropriate medications; reluctance of prescribers and patients to discontinue medication for fear of unfavourable sequelae; and uncertainty about effectiveness of strategies to reduce polypharmacy. Ways of countering such barriers comprise reframing the issue to one of highest quality patient-centred care; openly discussing benefit-harm trade-offs with patients and assessing their willingness to consider deprescribing; targeting patients according to highest risk of adverse drug events; targeting drugs more likely to be non-beneficial; accessing field-tested discontinuation regimens for specific drugs; fostering shared education and training in deprescribing among all members of the health care team; and undertaking deprescribing over an extended time frame under the supervision of a single generalist clinician.

Analysis of the propagation dynamics and Gouy phase of Airy beams using the fast Fresnel transform algorithm.

There is great interest in Airy beams because they appear to propagate in a curved path. These beams are usually generated by inserting a cubic phase mask onto the input plane of a Fourier transform system. Here, we utilize a fast Fresnel diffraction algorithm to easily derive both the propagation dynamics and the Gouy phase shift for these beams. The trajectories of these beams can be modified by adding additional linear and quadratic phase terms onto the cubic phase mask. Finally, we have rewritten the equations regarding the propagating Airy beams completely in laboratory coordinates for use by experimentalists. Experimental results are included. We expect that these results will be of great importance in applications of Airy beams.

Equations to predict female manual arm strength based on hand location relative to the shoulder.

The purpose of this study was to develop regression equations to predict manual arm strength for a wide variety of hand locations within the reach envelope. Maximum voluntary manual arm strength was determined from 71 female participants in six exertion directions (superior, inferior, anterior, posterior, medial and lateral), in a total of 28 hand locations. Forces ranged from 51.3 to 164.4 N, and had a pooled coefficient of variation of 29.9%. Across all 168 combinations of hand locations and exertion directions, the multivariate regression equations explained 92.5% of the variance and had a root mean square error (RMSE) of only 6.4 N, using only the anterior, lateral and vertical location of the hand relative to the active shoulder joint as inputs. These equations provide a proof-of-principle for our novel regression approach, and represent a first step towards a more comprehensive equation to estimate maximum acceptable forces for occupational tasks. PRACTITIONER SUMMARY: The equations presented here demonstrate a first step towards a novel and improved method to predict manual arm strength. Although a more comprehensive equation is still needed, these equations can be confidently used in the field by ergonomists to estimate the maximum acceptable forces in the six primary force directions.

Making A Difference: Launching a Multimodal, Resident-Run Social Emergency Medicine Program.

Introduction: Social medicine seeks to incorporate patients' social contexts into their medical care. Emergency physicians are uniquely positioned to address social determinants of health (SDoH) on the frontlines of the healthcare system. Miami-Dade County (MDC) is a diverse and socially vulnerable area. In 2020, the University of Miami-Jackson Health System (UM-JHS) emergency medicine (EM) residency program launched a multimodal, resident-led Social EM program to identify and address SDoH in the emergency department (ED). Methods: We use a four-pillar approach to SDoH in the ED: Curriculum Integration; Community Outreach; Access to Care; and Social Justice. Residents graduate with a knowledge of Social EM principles through an 18-month curriculum, an elective, and a longitudinal track. We developed sustainable initiatives through interdepartmental and community-based partnerships, including a Narcan distribution initiative, an ED-based program linking uninsured patients to follow-up care, a human trafficking education initiative, and a quality improvement initiative for incarcerated patients. Results: Given that the 18-month curriculum was launched in 2022, a full rotation of the curriculum had not been completed as of this writing, and data collection and analysis is an ongoing process. The initial pretest and post-test survey data show improvement in knowledge and confidence in managing Social EM topics. The Narcan initiative has screened 1,188 patients, of whom 144 have received Narcan. The ED-based patient navigation program has enrolled 31 patients to date, 18 of whom obtained outpatient care. Analysis of the impact/effectiveness of the program's other initiatives is ongoing. Conclusion: To our knowledge, this is one of the most robust social EM programs to date, as many other programs primarily focus on service opportunities. Rooted in the revised principles of Bloom's taxonomy of cognitive learning, this program moves beyond understanding Social EM tenets to generating solutions to address SDoH in and outside the ED.

Understanding Australian pharmacy degree holders' job preferences through the lens of motivation-hygiene theory.

Increasing the contribution of pharmacists to primary care has been long discussed, particularly in the context of health workforce shortages and the push to better integrate all providers across primary care. This study examines the employment preferences of Australian pharmacy degree holders (PDHs) elicited through a discrete choice experiment (DCE), to better understand the drivers of current labour force choices. A labelled DCE was developed incorporating the six employment sectors: hospital pharmacy, community pharmacy, primary healthcare settings, pharmaceutical industry, government/academia, and non-pharmacy-related sector. Each alternative was described by five attributes using Herzberg's Two Factor Theory as a conceptual framework. They include motivators - role and career opportunities, and hygiene factors-flexible work schedule, geographic location, and salary. Unforced choice data were analysed using conditional logit and mixed logit models. Based on a sample of 678 PDHs in Australia, our findings indicated pharmaceutical industry is the least preferred sector, followed by non-pharmacy-related sector. Motivators in the form of role and career opportunities are the most important attributes in hospital pharmacy while hygiene factors - geographic location and salary significantly drive the choice of community pharmacy and primary care settings. We provided evidence of a willingness to adopt expanded roles in community pharmacy. This unique interpretation of the key drivers of employment preference in light of motivators and hygiene factors provides policy makers with important information when designing policies to attract and retain PDHs across employment sectors.