Prescribed and Penalized: The Detrimental Impact of Mandated Reporting for Prenatal Utilization of Medication for Opioid Use Disorder.

OBJECTIVES: Some states, including Massachusetts, require automatic filing of child abuse and neglect for substance-exposed newborns, including infants exposed in-utero to clinician-prescribed medications to treat opioid use disorder (MOUD). The aim of this article is to explore effects of these mandated reporting policies on pregnant and postpartum people receiving MOUD. METHODS: We used modified grounded research theory, literature findings, and constant comparative methods to extract, analyze and contextualize perinatal experiences with child protection systems (CPS) and explore the impact of the Massachusetts mandated reporting policy on healthcare experiences and OUD treatment decisions. We drew from 26 semi-structured interviews originally conducted within a parent study of perinatal MOUD use in pregnancy and the postpartum period. RESULTS: Three themes unique to CPS reporting policies and involvement emerged. First, mothers who received MOUD during pregnancy identified mandated reporting for prenatally prescribed medication utilization as unjust and stigmatizing. Second, the stress caused by an impending CPS filing at delivery and the realities of CPS surveillance and involvement after filing were both perceived as harmful to family health and wellbeing. Finally, pregnant and postpartum individuals with OUD felt pressure to make medical decisions in a complex environment in which medical recommendations and the requirements of CPS agencies often compete. CONCLUSIONS FOR PRACTICE: Uncoupling of OUD treatment decisions in the perinatal period from mandated CPS reporting at time of delivery is essential. The primary focus for families affected by OUD must shift from surveillance and stigma to evidence-based treatment and access to supportive services and resources.

What is already known on this subject? Child protection systems (CPS) reporting is associated with barriers to prenatal care and family resources and services. Some state policies in the United States mandate reporting to CPS for prenatal substance exposure, including prescribed medications for opioid use disorder.What this study adds? This study centers the experiences of pregnant and postpartum people with opioid use disorder with mandated reporting policies for prenatal substance exposure, describes the harms to families associated with these policies, and makes recommendations for policy change. Findings emphasize the need to uncouple medical decisions from CPS reporting and involvement.

A multiomic approach to defining the essential genome of the globally important pathogen Corynebacterium diphtheriae.

Diphtheria is a respiratory disease caused by Corynebacterium diphtheriae. While the toxin-based vaccine has helped control outbreaks of the disease since the mid-20th century there has been an increase in cases in recent years, including systemic infections caused by non-toxigenic C. diphtheriae strains. Here we describe the first study of gene essentiality in C. diphtheriae, providing the most-dense Transposon Directed Insertion Sequencing (TraDIS) library in the phylum Actinobacteriota. This high-density library has allowed the identification of conserved genes across the genus and phylum with essential function and enabled the elucidation of essential domains within the resulting proteins including those involved in cell envelope biogenesis. Validation of these data through protein mass spectrometry identified hypothetical and uncharacterized proteins in the proteome which are also represented in the vaccine. These data are an important benchmark and useful resource for the Corynebacterium, Mycobacterium, Nocardia and Rhodococcus research community. It enables the identification of novel antimicrobial and vaccine targets and provides a basis for future studies of Actinobacterial biology.

Ruthenium Complexes with Protic Ligands: Influence of the Position of OH Groups and π Expansion on Luminescence and Photocytotoxicity.

Protic ruthenium complexes using the dihydroxybipyridine (dhbp) ligand combined with a spectator ligand (N,N = bpy, phen, dop, Bphen) have been studied for their potential activity vs. cancer cells and their photophysical luminescent properties. These complexes vary in the extent of π expansion and the use of proximal (6,6'-dhbp) or distal (4,4'-dhbp) hydroxy groups. Eight complexes are studied herein as the acidic (OH bearing) form, [(N,N)2Ru(n,n'-dhbp)]Cl2, or as the doubly deprotonated (O- bearing) form. Thus, the presence of these two protonation states gives 16 complexes that have been isolated and studied. Complex 7A, [(dop)2Ru(4,4'-dhbp)]Cl2, has been recently synthesized and characterized spectroscopically and by X-ray crystallography. The deprotonated forms of three complexes are also reported herein for the first time. The other complexes studied have been synthesized previously. Three complexes are light-activated and exhibit photocytotoxicity. The log(Do/w) values of the complexes are used herein to correlate photocytotoxicity with improved cellular uptake. For Ru complexes 1-4 bearing the 6,6'-dhbp ligand, photoluminescence studies (all in deaerated acetonitrile) have revealed that steric strain leads to photodissociation which tends to reduce photoluminescent lifetimes and quantum yields in both protonation states. For Ru complexes 5-8 bearing the 4,4'-dhbp ligand, the deprotonated Ru complexes (5B-8B) have low photoluminescent lifetimes and quantum yields due to quenching that is proposed to involve the 3LLCT excited state and charge transfer from the [O2-bpy]2- ligand to the N,N spectator ligand. The protonated OH bearing 4,4'-dhbp Ru complexes (5A-8A) have long luminescence lifetimes which increase with increasing π expansion on the N,N spectator ligand. The Bphen complex, 8A, has the longest lifetime of the series at 3.45 µs and a photoluminescence quantum yield of 18.7%. This Ru complex also exhibits the best photocytotoxicity of the series. A long luminescence lifetime is correlated with greater singlet oxygen quantum yields because the triplet excited state is presumably long-lived enough to interact with 3O2 to yield 1O2.

Fentanyl in the labor epidural impacts the results of intrapartum and postpartum maternal and neonatal toxicology tests.

BACKGROUND: A positive urine fentanyl toxicology test may have considerable consequences for peripartum individuals, yet the extent to which fentanyl administration in a labor epidural may lead to such a positive test is poorly characterized. OBJECTIVE: This study aimed to quantify the extent to which neuraxial fentanyl in labor neuraxial analgesia can lead to a positive peripartum maternal or neonatal urine toxicology test. STUDY DESIGN: We performed a prospective cohort study of pregnant participants planning a vaginal delivery with neuraxial analgesia. Participants with a history of substance use disorder, hypertension, or renal or liver disease were excluded. A urine sample was collected before initiation of neuraxial analgesia, each time the bladder was emptied during labor, and up to 4 times postpartum. Neonatal urine was collected once. Urine fentanyl testing was performed using 2 common toxicology testing methods, namely immunoassay and liquid chromatography with tandem mass spectrometric detection. RESULTS: A total of 33 maternal-infant dyads yielded a total of 178 urine specimens. All maternal specimens were negative for fentanyl using liquid chromatography with tandem mass spectrometric analysis and immunoassay before initiation of neuraxial analgesia. Intrapartum, 26 of 30 (76.7%) participants had positive liquid chromatography with tandem mass spectrometry results for fentanyl or its metabolites, and 12 of 30 (40%) participants had positive immunoassay results. Postpartum, 19 of 21 (90.5%) participants had positive liquid chromatograph with tandem mass spectrometric results, and 13 of 21 (61.9%) had a positive immunoassay result. Of the 13 neonatal specimens collected, 10 (76.9%) were positive on liquid chromatography with tandem mass spectrometry analysis, the last of which remained positive 29 hours and 50 minutes after delivery. CONCLUSION: Neuraxial fentanyl for labor analgesia may lead to positive maternal and neonatal toxicology tests at various times after epidural initiation and cessation and at different rates depending on the testing method used. Caution should be used in interpreting toxicology test results of individuals who received neuraxial analgesia to avoid false assumptions about nonprescribed use.

Production of Transgenic F0 Animals and Permanent Lines by Sperm Nuclear Transplantation in Xenopus tropicalis.

Early efforts in the 1980s showed that DNA microinjected into Xenopus embryos could be integrated into the genome and transmitted through the germline at low efficiency. Subsequent studies revealed that transgenic lines, typically with multiple-copy inserts (e.g., to develop bright fluorescent protein-reporter lines), could be created via sperm nuclear injection protocols such as the one entitled restriction enzyme-mediated insertion, or REMI. Here we describe a refined sperm nuclear injection procedure, with a number of alterations, including elimination of a potential DNA-damaging restriction enzyme treatment, aimed at making F0 transgenic animals and transgenic lines in Xenopus tropicalis This protocol also uses an oocyte extract rather than the egg extract used in older protocols. These changes simplify and improve the efficiency of the procedure.

Subcutaneous Extended-release Buprenorphine Depot Misdiagnosed as an Abscess Resulting in Incision and Drainage and Disruption of Opioid Use Disorder Treatment.

Monthly extended-release buprenorphine subcutaneous injection (BUP-XR) is a newer treatment formulation for use in moderate to severe opioid use disorder. After injection into the subcutaneous tissue of the abdomen, the medication forms a depot to allow for slow release of buprenorphine. As such, a small yet visible and palpable nodule is normal and is expected to decrease in size over the following weeks to months. Given the newness of this medication, it is possible that not all healthcare providers are familiar with this formulation, nor will they interpret the BUP-XR depot as normal findings. Herein, we provide a case report where a patient's BUP-XR depot was misdiagnosed as an abscess, resulting in incision and drainage and disruption of life-saving opioid use disorder treatment. To prevent cases like this in the future, it is important that providers administering BUP-XR properly educate patients on what to expect during treatment with BUP-XR and when to seek care for potential abnormalities. In addition, it is critical that healthcare providers working in other treatment settings are aware of how to properly evaluate BUP-XR injection sites.

What to Expect With Pregnant or Postpartum Prescribing of Extended-Release Buprenorphine (CAM2038).

Weekly and monthly CAM2038 (Brixadi®) extended-release subcutaneous buprenorphine (XR bup) has been available in Europe and Australia for several years and was approved by the Food and Drug Administration in May 2023. Little is known about the clinical experience of patients and providers using this new medication during prenatal care. Two cases of pregnant persons with opioid use disorder receiving weekly XR bup in an ongoing randomized multi-site outpatient clinical trial are presented along with a brief review of the pharmacology and literature on XR bup formulations. The cases in pregnancy illustrate how treatment with the weekly formulation is initiated including how to make dose adjustments, which may be necessary given the longer half-life; it takes 1 month to achieve steady state. Injection site pain with medication administration was time limited and managed readily. Other injection site reactions experienced included subcutaneous erythema and induration that was delayed in onset and typically mild, resolving with minimal intervention. Delivery management and breastfeeding recommendations while on weekly XR bup were not different compared to sublingual buprenorphine (SL bup). Weekly XR bup is a new treatment for opioid use disorder that may be used in the obstetric population. Obstetric and addiction medicine clinicians should be aware of this new formulation as its use is expected to increase.

Relation of red blood cell distribution width to risk of major adverse cardiovascular events, death, and effect of alirocumab after acute coronary syndromes.

Elevated red blood cell distribution width (RDW) is associated with increased risk for major adverse cardiovascular events (MACE) and death in patients with cardiovascular disease. The ODYSSEY OUTCOMES trial compared alirocumab with placebo in 18,924 patients with recent acute coronary syndrome (ACS) and elevated atherogenic lipoproteins despite optimized statin treatment. This post hoc analysis determined whether RDW independently predicts risk of MACE and death in patients after recent ACS, whether RDW influences MACE reduction with alirocumab, and whether alirocumab treatment affects RDW. Associations of baseline RDW with risk of MACE and death were analyzed in the placebo group in adjusted proportional hazards models. Interactions of RDW and treatment on the risk of MACE and death were evaluated. An increasing quartile of RDW was associated with characteristics that predicted risk of MACE and death including age, hypertension, diabetes, atherosclerotic conditions and events, revascularizations, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein. After adjusting for baseline characteristics associated with the risk of MACE or death, baseline RDW remained independently associated with the risk of MACE and death in the placebo group (hazard ratios [95% confidence intervals] 1.08 [1.02-1.15] and 1.13 [1.03-1.24] per 1% increase of RDW, respectively, both p <0.001). There was no interaction of RDW and treatment on MACE or death, nor did alirocumab affect RDW. RDW was associated with an increased risk of MACE and death, independent of established risk factors.

"You have to take this medication, but then you get punished for taking it:" lack of agency, choice, and fear of medications to treat opioid use disorder across the perinatal period.

INTRODUCTION: Medications to treat opioid use disorder (MOUD) during pregnancy and in the postpartum period remain underutilized. A need exists to enhance our understanding of modifiable factors, facilitators, and barriers to MOUD utilization and adherence in the perinatal period to improve maternal and child outcomes. METHODS: The study conducted semi-structured qualitative interviews with recently pregnant people with opioid use disorder (OUD) to explore experiences as a pregnant and/or parenting person with OUD, perceptions of enabling factors and barriers to treatment utilization, incentivizing factors for maintaining adherence, and acceptability of ongoing supports to sustain treatment adherence. The study team used constant comparative methods to analyze transcripts and develop the codebook. The team double coded the transcripts, with an overall kappa coefficient of 0.88. RESULTS: The study team interviewed twenty-six women on average 10.1 months after delivery. All women had some prior experience using MOUD. Four unique themes emerged as barriers to medication utilization and adherence in the perinatal period: 1) Lack of agency and autonomy surrounding medication decisions because pregnancy or parenting status affected treatment adherence; 2) Hesitancy to use MOUD to minimize risk of newborn withdrawal; 3) Concern about increased scrutiny and potential loss of custody due to mandated child protective services reporting for opioid-exposure at delivery in Massachusetts; and 4) Perception that treatment environments, particularly methadone clinics, did not provide gender-responsive or equitable care, and standardized, inflexible visit regulations were particularly difficult to comply with in the early postpartum period. CONCLUSIONS: Women with OUD experienced a double bind when making perinatal treatment decisions, describing pressure to use MOUD with negative consequences after delivery. Key areas for possible intervention emerged from interviews. These areas include improving uptake of shared decision-making to increase patient autonomy and agency, particularly among those in the earliest stages of recovery during pregnancy; ongoing education around perinatal MOUD safety and efficacy; detangling MOUD and neonatal withdrawal signs from mandated child protective services reporting; and improving gender-responsive and equitable care in substance use disorder treatment programs, including incorporating the utilization of home visiting services for dosing assessments and administration in the early postpartum period.

Saccoglossus kowalevskii: Evo-devo insights from the mud.

Hemichordates have long been recognized as a critical group for addressing hypotheses of chordate origins. Historically this was due to anatomical traits that resembled those of chordates, most strikingly the dorsolateral gill slits. As molecular data and phylogenetic analyses were found to support a close phylogenetic relationship between hemichordates and chordates within the deuterostomes, interest was revived in hemichordates. In particular, Saccoglossus kowalevskii has been developed as a molecular model to represent hemichordate developmental biology. Herein, we highlight the considerations when choosing a particular species to study and the challenges we encountered when developing S. kowalevskii. We discuss our findings and how method and tool development enabled them, and how we envision expanding our repertoire of molecular tools in the future. Establishing a new model organism comes with many obstacles-from identifying a reliable season to collect animals, to developing modern molecular techniques. The Saccoglossus research community has benefited greatly from the collaborations and teamwork established over the years. As a result, Saccoglossus is well positioned to contribute to a new century of evolutionary developmental (evo-devo) research.

Caring for Families Impacted by Opioid Use: A Qualitative Analysis of Integrated Program Designs.

OBJECTIVE: We sought to 1) identify models of integrated care that offer medical care and social services for children and families impacted by opioid use disorder (OUD) in the postpartum year; and 2) describe how each program was developed, designed, and sustained, and explore facilitators and barriers to implementation of a dyadic, two-generation approach to care. METHODS: In-depth semi-structured interviews (n = 23) were conducted with programs for women and children affected by OUD across North America. Using a phenomenologic approach, key program components and themes were identified. Following thematic saturation, these results were triangulated with experts in program implementation and with a subset of key informants to ensure data integrity. RESULTS: Five distinct types of programs were identified that varied in the degree of medical and behavioral care for families. Three themes emerged unique to the provision of dyadic care: 1) families require supportive, frequent visits with a range of providers, but constraints around billable services limit care integration across the perinatal continuum; 2) individual program champions are critical, but degree and reach of interdisciplinary care is limited by siloed systems for medical and behavioral care; and 3) addressing dual, sometimes competing, responsibilities for both parental and infant health following recurrence of parental substance use presents unique challenges. CONCLUSIONS: The key components of dyadic care models for families impacted by OUD included prioritizing care coordination, removing barriers to integrating medical and behavioral services, and ensuring the safety of children in homes with ongoing parental substance use while maintaining parental trust.

Light-responsive and Protic Ruthenium Compounds Bearing Bathophenanthroline and Dihydroxybipyridine Ligands Achieve Nanomolar Toxicity towards Breast Cancer Cells.

We report new ruthenium complexes bearing the lipophilic bathophenanthroline (BPhen) ligand and dihydroxybipyridine (dhbp) ligands which differ in the placement of the OH groups ([(BPhen)2 Ru(n,n'-dhbp)]Cl2 with n = 6 and 4 in 1A and 2A , respectively). Full characterization data are reported for 1A and 2A and single crystal X-ray diffraction for 1A . Both 1A and 2A are diprotic acids. We have studied 1A , 1B , 2A , and 2B (B = deprotonated forms) by UV-vis spectroscopy and 1 photodissociates, but 2 is light stable. Luminescence studies reveal that the basic forms have lower energy 3 MLCT states relative to the acidic forms. Complexes 1A and 2A produce singlet oxygen with quantum yields of 0.05 and 0.68, respectively, in acetonitrile. Complexes 1 and 2 are both photocytotoxic toward breast cancer cells, with complex 2 showing EC50 light values as low as 0.50 µM with PI values as high as >200 vs. MCF7. Computational studies were used to predict the energies of the 3 MLCT and 3 MC states. An inaccessible 3 MC state for 2B suggests a rationale for why photodissociation does not occur with the 4,4'-dhbp ligand. Low dark toxicity combined with an accessible 3 MLCT state for 1 O2 generation explains the excellent photocytotoxicity of 2.

Low barrier perinatal psychiatric care for patients with substance use disorder: meeting patients across the perinatal continuum where they are.

Pregnant and postpartum patients with substance use disorders (SUD) often have other co-occurring mental health disorders. Complications of substance use and mental health conditions, such as overdose and suicide, are a significant contributor to maternal morbidity and mortality. For individuals dually diagnosed with SUD and other mental health disorders, the perinatal period can be both a motivating and a vulnerable period for care. Barriers to optimal care include, but are not limited to, lack of screening, lack of referrals for care, a limited number of psychiatric providers available to care for pregnant patients, and stigma around mental health and addiction care in pregnancy. In this review, we discuss approaches to low-barrier perinatal psychiatric care for women with SUD to promote engagement in care. We review (1) appropriate psychiatric assessment and diagnostic work-up; (2) treatment planning incorporating shared-decision making, non-punitive and culturally sensitive patient-centred care, and principles of harm reduction with a focus on psychopharmacology, and (3) the benefits of an integrated and collaborative multidisciplinary care model for this subpopulation of vulnerable patients.

Analysis iron distribution methods in fine sand- and silt-sized soil particles.

Iron is prone to change its form and speciation in phases. Thus, several methods have been developed to estimate iron partitioning in the mineral phases of soils. However, the accuracy of these methods to evaluate the iron contribution from minor phases, such as actinolite, almandine, biotite, chlorite, epidote, hornblende, muscovite, and Fe-diospide, remains low. Furthermore, most of the current iron speciation research is focused on bulk samples, and only applies to soil samples that are mostly composed of clays or clay minerals, without a wide-ranging evaluation of soil particles with different grain sizes. In this study, we classified several iron phases using a mineral liberation analyzer on desert soil particles with diameters ranging from silt- to fine-sand (5-20 µm, 20-45 µm, 45-63 µm, 63-75 µm, and > 75 µm). The iron containing minor phases were identified, the modal mineral abundances were determined via matching with the standard energy dispersive spectra library, and a particle size analysis was performed using mineral processing tools on each of the examined 40,000 particles. The iron partition results were ultimately established based on the standard iron concentration in the mineral phases and the modal mineral abundances.•This new method could be automated, thereby facilitating high efficiency identification of iron-containing phases that would allow, for the first time, the generation of a dataset for iron partitioning in soil particles.•This method allows the identification of minor iron phases in soil particles, and permits in situ mapping of iron mineralogy in fine sand- to silt-sized soil particles.•Not restricted by single mineral particles, this method considers multi-phase complex particles. Thus, it largely improves the accuracy for estimating the iron partition parameter.

Integrating Harm Reduction into Outpatient Opioid Use Disorder Treatment Settings : Harm Reduction in Outpatient Addiction Treatment.

Opioid use disorder (OUD) is increasingly recognized as a chronic, relapsing brain disease whose treatment should be integrated into primary care settings alongside other chronic conditions. However, abstinence from all non-prescribed substance use continues to be prioritized as the only desired goal in many outpatient, primary care-based treatment programs. This presents a barrier to engagement for patients who continue to use substances and who may be at high risk for complications of ongoing substance use such as human immunodeficiency virus (HIV), hepatitis C virus (HCV), superficial and deep tissue infections, and overdose. Harm reduction aims to reduce the negative consequences of substance use and offers an alternative to abstinence as a singular goal. Incorporating harm reduction principles into primary care treatment settings can support programs in engaging patients with ongoing substance use and facilitate the delivery of evidence-based screening and prevention services. The objective of this narrative review is to describe strategies for the integration of evidence-based harm reduction principles and interventions into outpatient, primary care-based OUD treatment settings. We will offer specific tools for providers and programs including strategies to support safer injection practices, assess the risks and benefits of continuing medications for opioid use disorder in the setting of ongoing substance use, promote a non-stigmatizing program culture, and address the needs of special populations with ongoing substance use including adolescents, parents, and families.

Real-world outcomes with extended-release buprenorphine (XR-BUP) in a low threshold bridge clinic: A retrospective case series.

BACKGROUND: In clinical trial settings, extended-release buprenorphine (XR-BUP) is noninferior to sublingual buprenorphine and may offer some advantages. However, real-world experiences of XR-BUP are limited and outcomes are unknown for low-threshold clinics with high-risk populations. Practical guidance is lacking on overcoming treatment challenges, such as inability for some to stabilize on sublingual (SL) BUP for seven days prior to XR-BUP and ongoing craving/withdrawal symptoms during treatment. METHODS: Retrospective case series of a convenience sample of 40 serial adults with opioid use disorder (OUD) treated with XR-BUP from Massachusetts General Hospital bridge clinic from February 1, 2019, to July 31, 2019. RESULTS: Patients were mostly male (67.5%), non-Hispanic white (97.5%), unstably housed (77.5%), and average age of 32.1 years old. The average SL BUP dose prior to XR-BUP was 18.6 mg (standard deviation [SD] = 5; range 8-32) for an average treatment duration of 105 days (SD = 191; range 1-810). Ten (25%) patients received SL BUP for fewer than the seven recommended days (mean = 3.7, SD = 1.4, range = 1-6). Standard induction dosing was administered to 30%, empiric high-dose XR-BUP (300 mg monthly) was administered to 25%, and 55% were treated with supplemental SL BUP ranging from 4 to24mg, daily or as needed, for varying time periods. At the end of data collection, 65% remained on XR-BUP, 30% discontinued XR-BUP, and one patient was lost to follow-up. Acute care utilization rates were similar between patients who continued XR-BUP versus discontinued at 18.5% and 16.6%, respectively (χ2 = 0.02, p-value = 0.89). Toxicology was negative for other opioids in 65% of patients throughout treatment. There were no reports of overdose, withdrawal after use of opioids, or precipitated withdrawal after subsequent XR-BUP. Patients' most cited reason for discontinuing XR-BUP was a preference for SL BUP. CONCLUSION: This real-world evaluation of XR-BUP in a low-threshold clinic found that treatment was feasible, well tolerated, and outcomes were good, with most individuals choosing to continue treatment and a majority with no evidence of ongoing opioid use or precipitated withdrawal.

Colonisation dynamics of Listeria monocytogenes strains isolated from food production environments.

Listeria monocytogenes is a ubiquitous bacterium capable of colonising and persisting within food production environments (FPEs) for many years, even decades. This ability to colonise, survive and persist within the FPEs can result in food product cross-contamination, including vulnerable products such as ready to eat food items. Various environmental and genetic elements are purported to be involved, with the ability to form biofilms being an important factor. In this study we examined various mechanisms which can influence colonisation in FPEs. The ability of isolates (n = 52) to attach and grow in biofilm was assessed, distinguishing slower biofilm formers from isolates forming biofilm more rapidly. These isolates were further assessed to determine if growth rate, exopolymeric substance production and/or the agr signalling propeptide influenced these dynamics and could promote persistence in conditions reflective of FPE. Despite no strong association with the above factors to a rapid colonisation phenotype, the global transcriptome suggested transport, energy production and metabolism genes were widely upregulated during the initial colonisation stages under nutrient limited conditions. However, the upregulation of the metabolism systems varied between isolates supporting the idea that L. monocytogenes ability to colonise the FPEs is strain-specific.

Characterisation of Listeria monocytogenes food-associated isolates to assess environmental fitness and virulence potential.

The ability of Listeria monocytogenes isolates to survive within the food production environment (FPE), as well as virulence, varies greatly between strains. There are specific genetic determinants that have been identified which can strongly influence a strains ability to survive in the FPE and/or within human hosts. In this study, we assessed the FPE fitness and virulence potential, including efficacy of selected hygiene or treatment intervention, against 52 L. monocytogenes strains isolated from various food and food environment sources. Phenotypic tests were performed to determine the minimum inhibitory concentration of cadmium chloride and benzalkonium chloride and the sensitivities to five clinically relevant antibiotics. A genomic analysis was also performed to identify resistance genes correlating to the observed phenotypic resistance profiles, along with genetic determinants of interest which may elude to the FPE fitness and virulence potential. A transposon element containing a novel cadmium resistance gene, cadA7, a Tn916 variant insert in the hypervariable Listeria genomic island 1 region and an LGI2 variant were identified. Resistance to cadmium and disinfectants was prevalent among isolates in this study, although no resistance to clinically important antimicrobials was observed. Potential hypervirulent strains containing full length inlA, LIPI-1 and LIPI-3 were also identified in this study. Cumulatively, the results of this study show a vast array of FPE survival and pathogenicity potential among food production-associated isolates, which may be of concern for food processing operators and clinicians regarding L. monocytogenes strains colonising and persisting within the FPE, and subsequently contaminating food products then causing disease in at risk population groups.

Dataset of mineral contents of fine-sand and silt-sized soil particles from deserts in China and Mongolia.

There are over 70 types of mineral species in desert soils. Previous data have focused on major mineral contents and thus, the identification of minor mineral species is lacking. The diversity of minor mineral species was investigated in 19 surficial sediments from deserts in China and Mongolia. A modern scanning electron microscope (SEM)-based in-situ mineral mapping technique was used to determine the minor mineral species concentrations. For further analysis and interpretation, the identified species were grouped into felsic, mica, carbonate, heavy, rare earth, and salt-type minerals. The data in this article demonstrate that the concentrations of felsic, mica, and carbonate minerals are higher than those of the other mineral groups, and thus can be used to provide evidence of sediment provenance. The obtained mineral concentrations were converted from the relative area percentage for each mineral species using standard mineral density data. Mineral mapping was performed using the mineral liberation analysis platform, and on average, approximately 40,000 single particles per sample were analyzed to achieve an accurate quantification of the mineral concentrations. For each of the analyzed single particles, the particle shape parameters, such as particle length and width, were stored and can be used to trace the sediment transport process. For a deeper interpretation of the data presented herein, please see the related research article "Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles" [1].

Singlet Oxygen Formation vs Photodissociation for Light-Responsive Protic Ruthenium Anticancer Compounds: The Oxygenated Substituent Determines Which Pathway Dominates.

Ruthenium complexes bearing protic diimine ligands are cytotoxic to certain cancer cells upon irradiation with blue light. Previously reported complexes of the type [(N,N)2Ru(6,6'-dhbp)]Cl2 with 6,6'-dhbp = 6,6'-dihydroxybipyridine and N,N = 2,2'-bipyridine (bipy) (1A), 1,10-phenanthroline (phen) (2A), and 2,3-dihydro-[1,4]dioxino[2,3-f][1,10]phenanthroline (dop) (3A) show EC50 values as low as 4 µM (for 3A) vs breast cancer cells upon blue light irradiation ( Inorg. Chem. 2017, 56, 7519). Herein, subscript A denotes the acidic form of the complex bearing OH groups, and B denotes the basic form bearing O- groups. This photocytotoxicity was originally attributed to photodissociation, but recent results suggest that singlet oxygen formation is a more plausible cause of photocytotoxicity. In particular, bulky methoxy substituents enhance photodissociation but these complexes are nontoxic ( Dalton Trans 2018, 47, 15685). Cellular studies are presented herein that show the formation of reactive oxygen species (ROS) and apoptosis indicators upon treatment of cells with complex 3A and blue light. Singlet oxygen sensor green (SOSG) shows the formation of 1O2 in cell culture for cells treated with 3A and blue light. At physiological pH, complexes 1A-3A are deprotonated to form 1B-3B in situ. Quantum yields for 1O2 (ϕΔ) are 0.87 and 0.48 for 2B and 3B, respectively, and these are an order of magnitude higher than the quantum yields for 2A and 3A. The values for Ï•Δ show an increase with 6,6'-dhbp derived substituents as follows: OMe < OH < O-. TD-DFT studies show that the presence of a low lying triplet metal-centered (3MC) state favors photodissociation and disfavors 1O2 formation for 2A and 3A (OH groups). However, upon deprotonation (O- groups), the 3MLCT state is accessible and can readily lead to 1O2 formation, but the dissociative 3MC state is energetically inaccessible. The changes to the energy of the 3MLCT state upon deprotonation have been confirmed by steady state luminescence experiments on 1A-3A and their basic analogs, 1B-3B. This energy landscape favors 1O2 formation for 2B and 3B and leads to enhanced toxicity for these complexes under physiological conditions. The ability to convert readily from OH to O- groups allowed us to investigate an electronic change that is not accompanied by steric changes in this fundamental study.