LncRNA LOC730101 Promotes Darolutamide Resistance in Prostate Cancer by Suppressing miR-1-3p

Antiandrogen is part of the standard-of-care treatment option for metastatic prostate cancer. However, prostate cancers frequently relapse, and the underlying resistance mechanism remains incompletely understood. This study seeks to investigate whether long non-coding RNAs (lncRNAs) contribute to the resistance against the latest antiandrogen drug, darolutamide. Our RNA sequencing analysis revealed significant overexpression of LOC730101 in darolutamide-resistant cancer cells compared to the parental cells. Elevated LOC730101 levels were also observed in clinical samples of metastatic castration-resistant prostate cancer (CRPC) compared to primary prostate cancer samples. Silencing LOC730101 with siRNA significantly impaired the growth of darolutamide-resistant cells. Additional RNA sequencing analysis identified a set of genes regulated by LOC730101, including key players in the cell cycle regulatory pathway. We further demonstrated that LOC730101 promotes darolutamide resistance by competitively inhibiting microRNA miR-1-3p. Moreover, by Hi-C sequencing, we found that LOC730101 is located in a topologically associating domain (TAD) that undergoes specific gene induction in darolutamide-resistant cells. Collectively, our study demonstrates the crucial role of the lncRNA LOC730101 in darolutamide resistance and its potential as a target for overcoming antiandrogen resistance in CRPC.

Novel Image-Guided Percutaneous Lung Tissue Excision Device With Integrated Sealing of Blood Vessels and Airways: An In Vivo Preclinical Study

OBJECTIVE

This study evaluated the efficacy of the Minimally Invasive Targeted Resection (MiTR) device, a novel electrosurgical instrument that allows for targeted excision of a lung abnormality while using bipolar radiofrequency (RF) energy to seal blood vessels and airways.

METHODS

The MiTR system was evaluated in 7 acute and 2 chronic porcine (7-day) models to evaluate the efficacy of tissue excision with bipolar RF sealing of blood vessels and airways and application of an autologous blood patch into the excised tissue cavity. Air leak was recorded for all evaluations. The study was approved by the institutional ethical board.

RESULTS

Nineteen lung tissue samples, measuring 2.5 cm long × 1.2 cm diameter, were excised. In 8 of 9 animals (89%), hemostasis and pneumostasis were observed visually at the completion of the procedure. In 2 of 2 chronic animals (100%), hemostasis and pneumostasis persisted for the 7-day observation period. Histologic examination of the excised samples showed preservation of the core parenchymal architecture without evident tissue damage of the samples that would impair pathologic analysis.

CONCLUSIONS

Percutaneous resection of targeted lung tissue with the MiTR system demonstrated hemostasis and pneumostasis while obtaining a histologically intact sample. After regulatory approval, the use of this device could offer more tissue for analysis than a transthoracic needle biopsy or bronchoscopy and a far less invasive alternative to video-assisted thoracic surgery or thoracotomy. This may also expand patient and physician options for the early diagnosis and treatment of lung cancer.

Evaluation of the relevance of the growth modulation index (GMI) from the FFCD 0307 randomized phase III trial comparing the sequence of two chemotherapeutic regimens

BACKGROUND

Precision medicine trials disrupted the paradigm of randomized controlled trials in large populations. Patient selection may be based on molecular alterations rather than on primary tumor location. In small patient populations, the growth modulation index (GMI) has been developed to evaluate treatment efficacy by using each patient as its own control. The FFCD 0307 randomized phase III trial compared two sequences of chemotherapy in advanced gastric cancer, which represents a unique opportunity to evaluate the relevance of the GMI.

PATIENTS AND METHODS

In the FFCD 0307 trial, patients with advanced gastric cancer were randomized between two chemotherapy sequences [ECX followed by FOLFIRI at disease progression (arm A) versus FOLFIRI followed by ECX (arm B)]. GMI was defined as the ratio of the progression-free survival on second treatment (PFS2) to the time to progression on first treatment (TTP1). Sequence benefit was defined as a GMI exceeding 1.3 (GMI-high). GMI was correlated with overall survival (OS). OS1 and OS2 were measured from first randomization and second-line failure to death.

RESULTS

Four hundred and sixteen patients were randomized (209 in arm A, 207 in arm B). One hundred and seventy-five patients (42%) received the two sequences and were assessable for GMI (97 in arm A, 79 in arm B). The median GMI was higher in arm A than in arm B (0.62 versus 0.47, P = 0.04). Patients with a high GMI had a longer OS1 (median 14.9 versus 11.5 months, NS). Median OS2 was doubled in the GMI-high group (3.4 versus 1.6 months, NS).

CONCLUSION

GMI analyses suggest that ECX followed by FOLFIRI might represent a better therapeutic strategy than FOLFIRI followed by ECX. High GMI was associated with prolonged survival.

Doped Graphene Quantum Dots as Biocompatible Radical Scavenging Agents

Oxidative stress is proven to be a leading factor in a multitude of adverse conditions, from Alzheimer's disease to cancer. Thus, developing effective radical scavenging agents to eliminate reactive oxygen species (ROS) driving many oxidative processes has become critical. In addition to conventional antioxidants, nanoscale structures and metal-organic complexes have recently shown promising potential for radical scavenging. To design an optimal nanoscale ROS scavenging agent, we have synthesized ten types of biocompatible graphene quantum dots (GQDs) augmented with various metal dopants. The radical scavenging abilities of these novel metal-doped GQD structures were, for the first time, assessed via the DPPH, KMnO4, and RHB (Rhodamine B protectant) assays. While all metal-doped GQDs consistently demonstrate antioxidant properties higher than the undoped cores, aluminum-doped GQDs exhibit 60-95% radical scavenging ability of ascorbic acid positive control. Tm-doped GQDs match the radical scavenging properties of ascorbic acid in the KMnO4 assay. All doped GQD structures possess fluorescence imaging capabilities that enable their tracking in vitro, ensuring their successful cellular internalization. Given such multifunctionality, biocompatible doped GQD antioxidants can become prospective candidates for multimodal therapeutics, including the reduction of ROS with concomitant imaging and therapeutic delivery to cancer tumors.

Pediatric private practice in the Nord-Pas-de-Calais region: Demographics, organization, and challenges

While the needs for pediatric care are increasing and becoming more diverse, pediatric private practice in France is encountering difficulties linked to a growing medical demographic deficit. The objective of this study was to give an overview of pediatric private practice in the Nord-Pas-de-Calais region and to describe the main challenges encountered.

METHODS

For this descriptive observational survey, private practice pediatricians in the Nord-Pas-de-Calais region filled out an online questionnaire between April 2019 and October 2020.

RESULTS

The response rate was 64%. Most respondents practiced in an urban area (87%) and shared the practice with other physicians (59%). A majority (85%) had previously worked in hospital; 65% reported training in a subspecialty. Overall, 48% had other professional activities; 28% worked night shifts and 96% accepted urgent requests for consultations. A total of 33% reported having difficulties contacting specialists for consults, and 46% had difficulties in obtaining written reports of their patients' hospitalizations. All respondents participated in a form of ongoing medical education. The main difficulties were: lack of information about how to found a private practice (68%), lack of personal time (61%), balance between medical and administrative work (59%), and an excess of patients to care for (57%). The main satisfactions were: trusting relationships with patients (98%), freedom in their choice of practice (85%), and the diversity of problems and situations encountered (68%).

CONCLUSION

Our study underlines that private practice pediatricians are involved in healthcare provision, in particular regarding ongoing medical training, subspecialties, and continuity of care. It also highlights the problems encountered and the possible improvements: developing better communication between private practice and hospitals, reinforcing training during residency, and highlighting the importance and complementarity of private practice in children's healthcare.

TRAF4-mediated nonproteolytic ubiquitination of androgen receptor promotes castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) poses a major clinical challenge with the androgen receptor (AR) remaining to be a critical oncogenic player. Several lines of evidence indicate that AR induces a distinct transcriptional program after androgen deprivation in CRPCs. However, the mechanism triggering AR binding to a distinct set of genomic loci in CRPC and how it promotes CRPC development remain unclear. We demonstrate here that atypical ubiquitination of AR mediated by an E3 ubiquitin ligase TRAF4 plays an important role in this process. TRAF4 is highly expressed in CRPCs and promotes CRPC development. It mediates K27-linked ubiquitination at the C-terminal tail of AR and increases its association with the pioneer factor FOXA1. Consequently, AR binds to a distinct set of genomic loci enriched with FOXA1- and HOXB13-binding motifs to drive different transcriptional programs including an olfactory transduction pathway. Through the surprising upregulation of olfactory receptor gene transcription, TRAF4 increases intracellular cAMP levels and boosts E2F transcription factor activity to promote cell proliferation under androgen deprivation conditions. Altogether, these findings reveal a posttranslational mechanism driving AR-regulated transcriptional reprogramming to provide survival advantages for prostate cancer cells under castration conditions.

Personalized precision radiotherapy and its evolving role for human papillomavirus-positive oropharyngeal cancer

Human papilloma virus (HPV)-associated oropharyngeal cancer (OPC) is a unique entity with increased responsiveness to treatment and excellent oncologic outcomes. The purpose of this narrative review is to highlight how an improved prognosis for HPV (+) tumors and an ever-increasing understanding of the risk factors, risk stratification, and areas of potential spread are shaping management options. Additionally, we aim to detail how advances in treatment technology on both the surgical and radiation fronts are facilitating the delivery of increasingly personalized and precise treatments. This review will describe key aspects of recent and currently-ongoing trials investigating the de-escalation and individualization of treatment in this patient cohort, and how they are building a foundation for distinct treatment paradigms for HPV (+) tumors. Further studies into the integration of biomarker-guided treatments combined with clinical trial enrollment will help ensure a future of personalized treatments and improved outcomes, both in terms of oncologic outcomes and toxicity, for patients with HPV (+) OPC.

Abstract P225: Physical Activity and Heart Failure Prognosis in Older Postmenopausal Women

Background: Accumulating evidence suggests that participating in physical activity (PA) following heart failure (HF) diagnosis is associated with better prognosis, including lower mortality risk. Few studies have focused on this relationship in postmenopausal women, in whom HF burden is high.

Methods: The present study, conducted in the Women’s Health Initiative, included 2,181 postmenopausal women (mean age 68 years; 85% white, 10% black, 3% Hispanic at enrollment in 1993-1998) who were diagnosed postbaseline with incident hospitalized acute HF and had at least one self-reported PA assessment before and after (mean age 73 at latter assessment) HF diagnosis. Total recreational PA was summarized in metabolic equivalent (MET) hours per week. Women were followed for all-cause mortality from their post-HF PA assessment through March 2014. Cox regression with age as the time scale was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for mortality associated with PA categories (before/after HF): Inactive (<7.5 MET-hr/wk)/Inactive, n=1,048; Active (≥7.5 MET-hr/wk)/Inactive, n=407; Inactive/Active, n=212; Active/Active, n=514.

Results: There were 1,047 (48%) deaths during a mean follow-up of 12 years. Crude mortality rates per 1,000 person-years [number of deaths] across the above PA groups were 42.4 [533], 42.1 [206], 36.9 [94], and 34.7 [214]. After adjusting for age (timescale), race and ethnicity, and WHI study component, HRs (95% CI) for mortality across the PA groups were 1.00 (referent), 0.94 (0.79, 1.10), 0.80 (0.64, 1.01), and 0.60 (0.51, 0.71). Further adjustment for baseline education, BMI, physical function, smoking, menopausal hormone use, history of diabetes, hypertension, myocardial infarction, stroke, coronary revascularization, atrial fibrillation, and incident myocardial infarction during follow-up prior to HF diagnosis attenuated these associations but did not eliminate statistical significance for the Active/Active group: 1.00 (referent), 1.04 (0.87, 1.24), 0.87 (0.69, 1.10), 0.74 (0.62, 0.89). A similar pattern of results was evident when cardiovascular mortality was the study outcome.

Conclusions: Maintaining PA levels following hospitalization for acute HF was associated with lower all-cause mortality in older postmenopausal women, an understudied population in this regard. Among women whose PA following HF diagnosis was higher than their pre-HF PA level, there was a trend for lower mortality although this did not achieve statistical significance. Studies are needed to determine whether PA is associated with prognosis in HF subtypes, such as HF with preserved ejection which is a prevalent HF subtype in older women.

Automated Approach to In Vitro Image-Guided Photothermal Therapy with Top-Down and Bottom-Up-Synthesized Graphene Quantum Dots

Graphene-based materials have been the subject of interest for photothermal therapy due to their high light-to-heat conversion efficiency. Based on recent studies, graphene quantum dots (GQDs) are expected to possess advantageous photothermal properties and facilitate fluorescence image-tracking in the visible and near-infrared (NIR), while surpassing other graphene-based materials in their biocompatibility. Several GQD structures including reduced graphene quantum dots (RGQDs) derived from reduced graphene oxide via top-down oxidation and hyaluronic acid graphene quantum dots (HGQDs) hydrothermally bottom-up synthesized from molecular hyaluronic acid were employed to test these capabilities in the present work. These GQDs possess substantial NIR absorption and fluorescence throughout the visible and NIR beneficial for in vivo imaging while being biocompatible at up to 1.7 mg/mL concentrations. In aqueous suspensions, RGQDs and HGQDs irradiated with a low power (0.9 W/cm2) 808 nm NIR laser facilitate a temperature increase up to 47.0 °C, which is sufficient for cancer tumor ablation. In vitro photothermal experiments sampling multiple conditions directly in the 96-well plate were performed using an automated simultaneous irradiation/measurement system developed on the basis of a 3D printer. In this study, HGQDs and RGQDs facilitated the heating of HeLa cancer cells up to 54.5 °C, leading to the drastic inhibition of cell viability from over 80% down to 22.9%. GQD's fluorescence in the visible and NIR traces their successful internalization into HeLa cells maximized at 20 h suggesting both extracellular and intracellular photothermal treatment capabilities. The combination of the photothermal and imaging modalities tested in vitro makes the GQDs developed in this work prospective agents for cancer theragnostics.

Characteristics and outcomes of patients presenting with out of hospital cardiac arrest to a regional hospital

Funding Acknowledgements

Type of funding sources: None.

Introduction

Out of hospital cardiac arrest (OHCA) carries a high rate of mortality and can be due to cardiac or non-cardiac causes. We reviewed consecutive patients presenting with OHCA to the emergency department of a regional hospital in Australia, between January 2019 and March 2022. Medical records were reviewed to assess presenting rhythm, final diagnosis, risk factors known at time of presentation, results of cardiac investigations and survival to hospital discharge.

Results

Over the study period, 107 patients presented with cardiac arrest, with an average age of 67 years (range 29 to 95 years). Most patients were male (70, 67%), although in those with a non-cardiac cause identified only 53% were male. An underlying cardiac cause was identified in 50 (47%), a non-cardiac cause was identified in 18 (17%), and 39 (36%) had no identifiable cause. The most common cardiac causes were ST-elevation myocardial infarction (18, 36%), followed by non-ischaemic cardiomyopathy (9, 18%) and scar-related arrhythmia (7, 14%). Overall, ischaemic heart disease was responsible for 31 (62%) cases. Coronary angiography was performed in 36 (72%) of cardiac cases. Those who were diagnosed with ST-elevation myocardial infarction had an average time from presentation to coronary angiography of 61 minutes while the average was 38 hours for all patients presenting with OHCA. The most common presenting rhythm was ventricular fibrillation (39, 38%). The overall mortality rate was 61% for all OHCA. Among those with a cardiac cause, a non-cardiac cause or no cause identified for the OHCA, the mortality rates were 32%, 87% and 87% respectively. Data published by the regional Ambulance Service show that the survival to discharge from hospital of 39% in our regional hospital is comparable with state-wide outcomes.

Discussion

These data reflect the significant mortality and wide spectrum of disease underlying OHCA, and thus the challenge of managing patients presenting with OHCA. Cardiac disease accounts for almost half of all cases of OHCA, and also encompasses a wide spectrum of disease. However, the mortality in patients with OHCA due to an underlying cardiac cause, while still significant, is better than those patients in whom no cardiac cause is identified.

Characterizing and predicting the relationship between translaminar fracture toughness and pull-out length distributions under distinct temperatures

The translaminar fracture toughness reflects the damage tolerance of a fibre-reinforced composite under longitudinal tension, which often governs the final failure of structures. One of the main energy-dissipation mechanisms that contributes to the translaminar toughness of composites is the fibre pull-out process. The present study aims to quantify and model the statistical distribution of fibre pull-out lengths formed on the translaminar fracture surface of composites, for the first time in the literature; this is done under different temperatures, so that the relationship between pull-out length distributions, micromechanical properties and the translaminar fracture toughness can be established. The fracture surfaces of cross-ply compact tension specimens tested under three different temperatures have been scanned through X-ray computed tomography to quantify the extent of fibre pull-out on the fracture surfaces; the distribution of pull-out lengths showed alarger average and larger variability with an increase in temperature, which also lead to an increase in translaminar fracture toughness. A similar trend has been captured by the proposed analytical model, which predicts the pull-out length distribution based on the analysis of quasi-fractal idealizations of the fracture surface, yielding an overall accuracy of more than 85%. This article is part of the theme issue 'Ageing and durability of composite materials'.

Dual-Mode Fluorescence/Ultrasound Imaging with Biocompatible Metal-Doped Graphene Quantum Dots

Sonography offers many advantages over standard methods of diagnostic imaging due to its non-invasiveness, substantial tissue penetration depth, and low cost. The benefits of ultrasound imaging call for the development of ultrasound-trackable drug delivery vehicles that can address a variety of therapeutic targets. One disadvantage of the technique is the lack of high-precision imaging, which can be circumvented by complementing ultrasound contrast agents with visible and, especially, near-infrared (NIR) fluorophores. In this work, we, for the first time, develop a variety of lightly metal-doped (iron oxide, silver, thulium, neodymium, cerium oxide, cerium chloride, and molybdenum disulfide) nitrogen-containing graphene quantum dots (NGQDs) that demonstrate high-contrast properties in the ultrasound brightness mode and exhibit visible and/or near-infrared fluorescence imaging capabilities. NGQDs synthesized from glucosamine precursors with only a few percent metal doping do not introduce additional toxicity in vitro, yielding over 80% cell viability up to 2 mg/mL doses. Their small (<50 nm) sizes warrant effective cell internalization, while oxygen-containing surface functional groups decorating their surfaces render NGQDs water soluble and allow for the attachment of therapeutics and targeting agents. Utilizing visible and/or NIR fluorescence, we demonstrate that metal-doped NGQDs experience maximum accumulation within the HEK-293 cells 6-12 h after treatment. The successful 10-fold ultrasound signal enhancement is observed at 0.5-1.6 mg/mL for most metal-doped NGQDs in the vascular phantom, agarose gel, and animal tissue. A combination of non-invasive ultrasound imaging with capabilities of high-precision fluorescence tracking makes these metal-doped NGQDs a viable agent for a variety of theragnostic applications.

Technology Usage and Impacts by COVID-19 among Patients in a Radiation Oncology Clinic

Purpose/Objective(s)

Mobile devices provide platforms for consistent and real time symptom tracking for cancer patients, allowing for better symptom reporting and more timely interventions. There is limited research investigating barriers to adoption within the oncology setting and COVID-19 impacts on patent willingness to use health technology. Understanding these issues is key to successful development and implementation. We designed a survey to assess patient willingness and barriers to using mobile devices to report/track symptoms (e-report).

Materials/Methods

Two cohorts of adult patients completed a 21-question anonymized survey. The survey was administered to clinic patients before (PRE) and 18mo after (POST) the start of the COVID pandemic. Three additional questions were added to POST survey to investigate impacts from COVID. Demographics, technology usage, willingness to report data, barriers to utilization, and changes due to COVID were evaluated using descriptive statistics. Predictors of willingness to e-report, barriers to use, and changes due to the COVID-19 pandemic were analyzed using univariate and multivariate logistic regression (MVA).

Results

318 patients completed the survey (PRE= 144 patients; POST= 174 patients) with mean age 65y, 75% Caucasian, 55% male. Altogether, 75% used a smart phone (PRE=66.7%; POST=81.3%; p 0.003), 90% reported home internet access (PRE=87.5%; POST=91.4%; p 0.259), 86% used a computer (PRE=79.2%; POST=90.8%; p 0.004), and 26% used a wearable health tracker (PRE 25.7%; POST 26.4%; p 0.881). On MVA, age>65 (OR 0.32; p 0.001), annual income>50K (OR 2.16; p 0.032), smart phone ownership (OR 4.07; p 0.000), and new/current patient status (OR 2.15; p 0.020) were all significant factors impacting willingness to e- report. Limited tech literacy (p 0.024) and time commitment (p 0.048) were the only significant barriers. Privacy as a barrier was greater in PRE vs POST cohort (OR 2.3 vs OR 1.1) trending toward significance. Nearly all modes of tech usage were greater in POST vs PRE cohort. POST cohort was significantly more willing to e- report (81.1% vs 69.1%; OR 1.91; p 0.016). This remained significant on MVA after adjusting for age, concern for privacy, tech literacy, and patient status (OR 1.88; p 0.026). Furthermore, 51% of POST cohort reported the pandemic directly influenced their willingness to e-report (40% more, 11% less).

Conclusion

Radiation oncology patients are willing to use mobile technology to report symptoms. Willingness increases with decreasing age, increasing annual income, smartphone ownership, and new/current patient status. Significant barriers include tech literacy and time commitment. Post-pandemic patients are more willing to e-report and list fewer barriers. The COVID-19 pandemic appears to have had a positive impact on technology usage by patients. Efforts to develop and test mobile applications for this population are justified.

Detection of Pancreatic Cancer miRNA with Biocompatible Nitrogen-Doped Graphene Quantum Dots

Early-stage pancreatic cancer remains challenging to detect, leading to a poor five-year patient survival rate. This obstacle necessitates the development of early detection approaches based on novel technologies and materials. In this work, the presence of a specific pancreatic cancer-derived miRNA (pre-miR-132) is detected using the fluorescence properties of biocompatible nitrogen-doped graphene quantum dots (NGQDs) synthesized using a bottom-up approach from a single glucosamine precursor. The sensor platform is comprised of slightly positively charged (1.14 ± 0.36 mV) NGQDs bound via π-π stacking and/or electrostatic interactions to the negatively charged (-22.4 ± 6.00 mV) bait ssDNA; together, they form a complex with a 20 nm average size. The NGQDs' fluorescence distinguishes specific single-stranded DNA sequences due to bait-target complementarity, discriminating them from random control sequences with sensitivity in the micromolar range. Furthermore, this targetability can also detect the stem and loop portions of pre-miR-132, adding to the practicality of the biosensor. This non-invasive approach allows cancer-specific miRNA detection to facilitate early diagnosis of various forms of cancer.

Acute Multi-Organ Toxicity During 24-Hour Dosing of Intravenous Amiodarone: A Case Report

We present a unique case of a 60-year-old male with congestive heart failure who was admitted for a pre-syncopal episode and found to be in atrial fibrillation with rapid ventricular response (RVR). In order to effectively rate control the patient, he was administered an amiodarone bolus and intravenous (IV) infusion over 24 hours, along with a single oral 200 mg dose the following day. The patient subsequently developed acute hepatotoxicity along with features of acute kidney injury (AKI), pulmonary distress, and leukocytosis. After ruling out other etiologies for acute liver, pulmonary, and kidney injury, amiodarone-induced multi-organ toxicity was suspected and amiodarone was discontinued. Within hours of amiodarone discontinuation, the patient’s clinical status and organ function improved remarkably. In the setting of a patient being treated with IV amiodarone and presenting with sudden signs of dyspnea, acute elevation of transaminases and AKI within one to two days of initial dosing, acute amiodarone-induced organ toxicity should be considered.

Cranial manipulation affects cholinergic pathway gene expression in aged rats

CONTEXT

Age-dependent dementia is a devastating disorder afflicting a growing older population. Although pharmacological agents improve symptoms of dementia, age-related comorbidities combined with adverse effects often outweigh their clinical benefits. Therefore, nonpharmacological therapies are being investigated as an alternative. In a previous pilot study, aged rats demonstrated improved spatial memory after osteopathic cranial manipulative medicine (OCMM) treatment.

OBJECTIVES

In this continuation of the pilot study, we examine the effect of OCMM on gene expression to elicit possible explanations for the improvement in spatial memory.

METHODS

OCMM was performed on six of 12 elderly rats every day for 7 days. Rats were then euthanized to obtain the brain tissue, from which RNA samples were extracted. RNA from three treated and three controls were of sufficient quality for sequencing. These samples were sequenced utilizing next-generation sequencing from Illumina NextSeq. The Cufflinks software suite was utilized to assemble transcriptomes and quantify the RNA expression level for each sample.

RESULTS

Transcriptome analysis revealed that OCMM significantly affected the expression of 36 genes in the neuronal pathway (false discovery rate [FDR] <0.004). The top five neuronal genes with the largest-fold change were part of the cholinergic neurotransmission mechanism, which is known to affect cognitive function. In addition, 39.9% of 426 significant differentially expressed (SDE) genes (FDR<0.004) have been previously implicated in neurological disorders. Overall, changes in SDE genes combined with their role in central nervous system signaling pathways suggest a connection to previously reported OCMM-induced behavioral and biochemical changes in aged rats.

CONCLUSIONS

Results from this pilot study provide sufficient evidence to support a more extensive study with a larger sample size. Further investigation in this direction will provide a better understanding of the molecular mechanisms of OCMM and its potential in clinical applications. With clinical validation, OCMM could represent a much-needed low-risk adjunct treatment for age-related dementia including Alzheimer's disease.

Differences in antimicrobial susceptibility testing complicating management of IMP carbapenemase-producing Enterobacterales infection

OBJECTIVES

IMP-type carbapenemases are rarely detected in Europe and limited information is available to guide the treatment of infections caused by carbapenemase-producing Enterobacterales (CPE) producing these carbapenemases. Accurate antimicrobial susceptibility testing (AST) results are essential for optimal antibiotic management. Here we report discrepancies in AST of IMP-producing Enterobacterales (IMP-CPE) complicating the management of severe sepsis.

METHODS

Antimicrobial susceptibilities were analysed by in-house VITEK® 2, Etest and broth microdilution (BMD). Carbapenemase-encoding genes were detected by PCR. Whole-genome sequencing (WGS) was performed using an Illumina MiSeq platform.

RESULTS

Minimum inhibitory concentrations (MICs) determined by VITEK® 2 for Enterobacter hormaechei and Klebsiella oxytoca blood culture isolates were ≥16 mg/L for meropenem and ≤0.5 mg/L for ertapenem. In contrast, Etest analysis and BMD returned MICs of 2 mg/L and 1 mg/L, respectively. Both isolates tested positive for IMP carbapenemase-encoding genes by PCR. WGS revealed that both isolates carried the same bla_IMP-4 gene. Based on VITEK® 2 susceptibilities, initial treatment was with tigecycline and amikacin. After subsequent deterioration, the patient was successfully treated with ertapenem and amikacin.

CONCLUSION

This case highlights that automated AST by VITEK® 2 can over-report meropenem resistance for IMP carbapenemase-producers compared with Etest and BMD. Clinicians need to be cautious deciding against carbapenem treatment based on VITEK® 2 susceptibility testing results for IMP-positive Enterobacterales. Tigecycline was inferior to carbapenem treatment for pyelonephritis caused by isolates expressing IMP carbapenemases, however specific evidence guiding the treatment of these infections is lacking.

Cyclophosphamide and prednisolone for chemotherapy naïve B cell multicentric lymphoma in dogs: 32 cases (2017-2021)

OBJECTIVES

The aim of this study was to characterise the response rate and toxicity profile of cyclophosphamide and prednisolone given to dogs with newly diagnosed, chemotherapy naïve, B cell multicentric lymphoma.

MATERIALS AND METHODS

Dogs with diagnosed with B cell lymphoma naïve to chemotherapy treatment were prospectively identified at the author's institution (2017 to 2021) and given cyclophosphamide as their initial chemotherapeutic agent in combination with prednisolone with owner's consent. Signalment, laboratory findings, stage, treatment response and toxicity were recorded.

RESULTS

Thirty-two dogs were included in the study. The overall response rate in this population of dogs was 84%. Twenty dogs (62%) had a partial response, three dogs (9%) had a complete response, four dogs (12%) had stable disease and five dogs (15%) had progressive disease. Side effects were noted in 47% of patients, with neutropaenia being the most commonly reported.

CLINICAL SIGNIFICANCE

Cyclophosphamide and prednisolone were well-tolerated with limited side effects. The response rate observed in this cohort of dogs with chemotherapy-naïve B cell multicentric lymphoma is promising. Further comparative studies are required to confirm the safety and effectiveness of this intervention.