The effect of excessive gas to blood ratios in an ECMO oxygenator.

INTRODUCTION: Oxygenators for paediatric Extracorporeal Membrane Oxygenation (ECMO) are required to operate over a wide range of flow rates, in a patient group ranging from neonates through to fully grown adolescents. ECMO oxygenators typically have a manufacturer's stated maximum gas: blood flow rate (GBFR) ratio of 2:1, however, many patients require greater ratios than this for adequate CO2 removal. Mismatches in GBFR in theory could result in high gas phase pressures. These increased pressures in theory could cause the formation of gross gaseous microemboli (GME) placing the child at higher risk of neurological injury. METHODS: We evaluated 6 paediatric and 6 adult A.L.ONE™ ECMO oxygenators and assessed their gas phase pressures and GME release, in an ex vivo setting, in GBFR ratios up to greater than 2, across a range of gas flow (1L - 10 L/min) rates with a fraction of inspired oxygen (FiO2) content of 50% and 100%. RESULTS: There were no increases above 10 mmHg observed in gas phase pressures in GBFR >= 2:1 in either adult or paediatric oxygenators. Laboratory examination of GME activity demonstrated a small increase in post-membrane GME release over the study period. GME release was unaffected by FiO2 setting or gas flow rate, with a maximum volume of < 6 µL in both paediatric and adult oxygenators. CONCLUSIONS: In an ex vivo setting, increasing GBFR above 2:1 in a paediatric oxygenator, and to a GBFR of 2:1 in an adult oxygenator did not significantly increase gas phase pressures, and no oxygenator membrane rupture was observed. There were no associations between gas flow rates and GME production.

The influence of internal pressure and neuromuscular agents on C. elegans biomechanics: an empirical and multi-compartmental in silico modelling study.

The function of a specific tissue and its biomechanics are interdependent, with pathologies or ageing often being intertwined with structural decline. The biomechanics of Caenorhabditis elegans, a model organism widely used in pharmacological and ageing research, has been established as biomarker for healthy ageing. However, the properties of the constituent tissues, and their contribution to the overall mechanical characteristics of the organism, remain relatively unknown. In this study we investigated the biomechanics of healthy C. elegans cuticle, muscle tissue, and pseudocoelom using a combination of indentation experiments and in silico modelling. We performed stiffness measurements using an atomic force microscope. To approximate the nematode's cylindrical body we used a novel three-compartment nonlinear finite element model, enabling us to analyse of how changes in the elasticity of individual compartments affect the bulk stiffness. We then fine-tuned the parameters of the model to match the simulation force-indentation output to the experimental data. To test the finite element model, we modified distinct compartments experimentally. Our in silico results, in agreement with previous studies, suggest that hyperosmotic shock reduces stiffness by decreasing the internal pressure. Unexpectedly, treatment with the neuromuscular agent aldicarb, traditionally associated with muscle contraction, reduced stiffness by decreasing the internal pressure. Furthermore, our finite element model can offer insights into how drugs, mutations, or processes such as ageing target individual tissues.

Clinical outcomes of traumatic globe rupture in corneal graft patients.

PURPOSE: This study reports the mechanisms, complications and graft survival following sight-threatening traumatic globe rupture in patients having previously undergone corneal transplantation in the same eye. METHODS: A retrospective, observational, single-center consecutive cohort study at the Royal Victoria Infirmary, Newcastle upon Tyne, UK over a 20-year period. Medical records and Newcastle Corneal Transplantation Service electronic database (eNCTS) review was undertaken of all consecutive patients who underwent corneal transplantation with a history of traumatic globe rupture. Main outcome measures include mechanism of injury, final best-corrected distance visual acuity (BCDVA), graft survival and complications. RESULTS: A total of 921 keratoplasties were undertaken between 1997 and 2017 with 24 (3.0%) patients identified with a history of traumatic globe rupture. A bimodal relationship of age and mechanism of trauma was observed. The mean age (SD) of individuals reporting cause as a fall was 71.5 (14.8) years, and 45.3 (20.8) years (P < 0.05) amongst individuals reporting accidental trauma or assault. The pre- and post-trauma mean (SD) LogMAR BCDVA was 0.6 (0.9) and 1.7 (1.0), respectively (P = 0.001). The overall graft-failure rate was 60.9% (11 grafts) during a mean (SD) follow-up period of 3.5 (4.1) years. Globe rupture with lens damage was associated with poorer final BCDVA (P < 0.05). CONCLUSIONS: This study represents the first published series from England for this type of patient cohort. Overall visual outcomes were poor with a bimodal relationship of age and mechanism of trauma. Worse prognostic factors included lens and posterior segment complications. Re-grafting in these select group of patients may prove valuable.

Microbiota-dependent activation of CD4+ T cells induces CTLA-4 blockade-associated colitis via Fcγ receptors.

Immune checkpoint inhibitors can stimulate antitumor immunity but can also induce toxicities termed immune-related adverse events (irAEs). Colitis is a common and severe irAE that can lead to treatment discontinuation. Mechanistic understanding of gut irAEs has been hampered because robust colitis is not observed in laboratory mice treated with checkpoint inhibitors. We report here that this limitation can be overcome by using mice harboring the microbiota of wild-caught mice, which develop overt colitis following treatment with anti-CTLA-4 antibodies. Intestinal inflammation is driven by unrestrained activation of IFNγ-producing CD4+ T cells and depletion of peripherally induced regulatory T cells through Fcγ receptor signaling. Accordingly, anti-CTLA-4 nanobodies that lack an Fc domain can promote antitumor responses without triggering colitis. This work suggests a strategy for mitigating gut irAEs while preserving antitumor stimulating effects of CTLA-4 blockade.

Rapid desensitization through immunoadsorption during cardiopulmonary bypass. A novel method to facilitate human leukocyte antigen incompatible heart transplantation.

BACKGROUND: Anti-human leukocyte antigen (HLA)-antibody production represents a major barrier to heart transplantation, limiting recipient compatibility with potential donors and increasing the risk of complications with poor waiting-list outcomes. Currently there is no consensus to when desensitization should take place, and through what mechanism, meaning that sensitized patients must wait for a compatible donor for many months, if not years. We aimed to determine if intraoperative immunoadsorption could provide a potential desensitization methodology. METHODS: Anti-HLA antibody-containing whole blood was added to a Cardiopulmonary bypass (CPB) circuit set up to mimic a 20 kg patient undergoing heart transplantation. Plasma was separated and diverted to a standalone, secondary immunoadsorption system, with antibody-depleted plasma returned to the CPB circuit. Samples for anti-HLA antibody definition were taken at baseline, when combined with the CPB prime (on bypass), and then every 20 min for the duration of treatment (total 180 min). RESULTS: A reduction in individual allele median fluorescence intensity (MFI) to below clinically relevant levels (<1000 MFI), and in the majority of cases below the lower positive detection limit (<500 MFI), even in alleles with a baseline MFI >4000 was demonstrated. Reduction occurred in all cases within 120 min, demonstrating efficacy in a time period usual for heart transplantation. Flowcytometric crossmatching of suitable pseudo-donor lymphocytes demonstrated a change from T cell and B cell positive channel shifts to negative, demonstrating a reduction in binding capacity. CONCLUSIONS: Intraoperative immunoadsorption in an ex vivo setting demonstrates clinically relevant reductions in anti-HLA antibodies within the normal timeframe for heart transplantation. This method represents a potential desensitization technique that could enable sensitized children to accept a donor organ earlier, even in the presence of donor-specific anti-HLA antibodies.

Engaging communities to inform the development of a diverse cohort of cancer survivors: formative research for the eat move sleep study (EMOVES).

BACKGROUND: There are more than 18 million cancer survivors in the United States. Yet, survivors of color remain under-represented in cancer survivorship research (Saltzman et al. in Contemp Clin Trials Commun 29:100986, 2022; Pang et al. in J Clin Oncol 34:3992-3999, 2016; Lythgoe et al. in Prostate Cancer Prostatic Dis 24:1208-1211, 2021). Our long-term goal is to enroll and follow a cohort of historically under-represented cancer survivors, to better understand modifiable risk factors that influence clinical and quality of life outcomes in these populations. Towards that goal, we describe herein how we applied community-based participatory research approaches to develop inclusive study materials for enrolling such a cohort. METHODS: We implemented community engagement strategies to inform and enhance the study website and recruitment materials for this cohort including: hiring a dedicated engagement coordinator/community health educator as a member of our team; working with the Helen Diller Family Comprehensive Cancer Center Office of Community Engagement (OCE) and Community Advisory Board members; presenting our educational, research, and study recruitment materials at community events; and establishing a community advisory group specifically for the study (4 individuals). In parallel with these efforts, 20 semi-structured user testing interviews were conducted with diverse cancer survivors to inform the look, feel, and usability of the study website. RESULTS: Engagement with community members was a powerful and important approach for this study's development. Feedback was solicited and used to inform decisions regarding the study name (eat move sleep, EMOVES), logo, study website content and imagery, and recruitment materials. Based on community feedback, we developed additional educational materials on healthy groceries and portion size in multiple languages and created a study video. CONCLUSIONS: Including an engagement coordinator as a permanent team member, partnering with the institutional community outreach and engagement resources (i.e., OCE), and allocating dedicated time and financial support for cultivating relationships with stakeholders outside the university were critical to the development of the study website and materials. Our community guided strategies will be tested as we conduct enrollment through community advisor networks and via the state cancer registry.

Under-represented racial and ethnic populations are diagnosed with and die from cancer at higher rates than white Americans but are less likely to be included in research studies. This has resulted in limited data on these populations, especially regarding cancer survivorship and lifestyle factors such as diet, exercise, and sleep. Our aim was to develop inclusive and appealing study materials for enrolling a diverse cancer survivorship cohort by integrating a community engagement coordinator/health educator into the research team and collaborating with our cancer center's office of community engagement community advisory board. An additional bridge was developed between community partners and the research team by establishing a community advisory board specifically for the study. We also conducted 20 user testing interviews with cancer survivors and community stakeholders to inform the look, feel, and usability of the study website during development. Our community partnerships and interviews assisted with decisions on our study name, Eat Move Sleep Study (EMOVES), logo, redesigning the study website, and study format. Our partners also provided guidance that highlighted community need and development of new educational materials for healthy diet (postcard sized grocery list on healthy eating) and a video-based recruitment tool for the study. Incorporation of an engagement coordinator into the research team, building an ongoing relationship with our cancer center's office of community engagement, and adding community advisors onto our study team has greatly impacted our study approach and design.

Nanoprojectile Secondary Ion Mass Spectrometry Enables Multiplexed Analysis of Individual Hepatic Extracellular Vesicles.

Extracellular vesicles (EVs) are nanoscale lipid bilayer particles secreted by cells. EVs may carry markers of the tissue of origin and its disease state, which makes them incredibly promising for disease diagnosis and surveillance. While the armamentarium of EV analysis technologies is rapidly expanding, there remains a strong need for multiparametric analysis with single EV resolution. Nanoprojectile (NP) secondary ion mass spectrometry (NP-SIMS) relies on bombarding a substrate of interest with individual gold NPs resolved in time and space. Each projectile creates an impact crater of 10-20 nm in diameter while molecules emitted from each impact are mass analyzed and recorded as individual mass spectra. We demonstrate the utility of NP-SIMS for statistical analysis of single EVs derived from normal liver cells (hepatocytes) and liver cancer cells. EVs were captured on antibody (Ab)-functionalized gold substrate and then labeled with Abs carrying lanthanide (Ln) MS tags (Ab@Ln). These tags targeted four markers selected for identifying all EVs, and specific to hepatocytes or liver cancer. NP-SIMS was used to detect Ab@Ln-tags colocalized on the same EV and to construct scatter plots of surface marker expression for thousands of EVs with the capability of categorizing individual EVs. Additionally, NP-SIMS revealed information about the chemical nanoenvironment where targeted moieties colocalized. Our approach allowed analysis of population heterogeneity with single EV resolution and distinguishing between hepatocyte and liver cancer EVs based on surface marker expression. NP-SIMS holds considerable promise for multiplexed analysis of single EVs and may become a valuable tool for identifying and validating EV biomarkers of cancer and other diseases.

Signal conversion as tumor micro environment (TME) specifically activated cytokine.

Targeted cytokine delivery has been gaining popularity in cancer immunotherapy since systemic recombinant cytokine treatment has not been successful due to low response rate and systemic toxicities in the clinical studies. In order to address these issues, we propose a new concept that cytokine signal is specifically activated at tumor-micro-environment (TME) by delivering two protein subunits of heterodimeric cytokine fused with a tumor targeting antibody respectively to TME and by bridging the two subunits into active heterodimeric form.Interleukin-12 (IL-12) is one of the major cytokines which can induce immune activation. IL-12 consists of two protein subunits which are p35 and p40. IL-12 signaling is initiated when it forms as the heterodimeric protein and binds to IL-12 receptor complex. We made fusion proteins of both IL-12p35 and IL-12p40 targeting specific tumor associated antigens (TAAs) and demonstrated the formation of bioactive IL12p70 with TME targeting antibody toward both p35 and p40 to form as the active molecule. We describe our concept validation in an in vitro based functional assay.

Nanoprojectile Secondary Ion Mass Spectrometry Enables Multiplexed Analysis of Individual Hepatic Extracellular Vesicles.

Extracellular vesicles (EVs) are nanoscale lipid bilayer particles secreted by cells. EVs may carry markers of the tissue of origin and its disease state which makes them incredibly promising for disease diagnosis and surveillance. While the armamentarium of EV analysis technologies is rapidly expanding, there remains a strong need for multiparametric analysis with single EV resolution. Nanoprojectile (NP) secondary ion mass spectrometry (NP-SIMS) relies on bombarding a substrate of interest with individual gold NPs resolved in time and space. Each projectile creates an impact crater of 10-20 nm in diameter while molecules emitted from each impact are mass analyzed and recorded as individual mass spectra. We demonstrate the utility of NP-SIMS for analysis of single EVs derived from normal liver cells (hepatocytes) and liver cancer cells. EVs were captured on antibody (Ab)-functionalized gold substrate then labeled with Abs carrying lanthanide (Ln) MS tags (Ab@Ln). These tags targeted four markers selected for identifying all EVs, and specific to hepatocytes or liver cancer. NP-SIMS was used to detect Ab@Ln-tags co-localized on the same EV and to construct scatter plots of surface marker expression for thousands of EVs with the capability of categorizing individual EVs. Additionally, NP-SIMS revealed information about the chemical nano-environment where targeted moieties co-localized. Our approach allowed analysis of population heterogeneity with single EV resolution and distinguishing between hepatocyte and liver cancer EVs based on surface marker expression. NP-SIMS holds considerable promise for multiplexed analysis of single EVs and may become a valuable tool for identifying and validating EV biomarkers of cancer and other diseases.

Minimum resolution requirements of digital pathology images for accurate classification.

Digitization of pathology has been proposed as an essential mitigation strategy for the severe staffing crisis facing most pathology departments. Despite its benefits, several barriers have prevented widespread adoption of digital workflows, including cost and pathologist reluctance due to subjective image quality concerns. In this work, we quantitatively determine the minimum image quality requirements for binary classification of histopathology images of breast tissue in terms of spatial and sampling resolution. We train an ensemble of deep learning classifier models on publicly available datasets to obtain a baseline accuracy and computationally degrade these images according to our derived theoretical model to identify the minimum resolution necessary for acceptable diagnostic accuracy. Our results show that images can be degraded significantly below the resolution of most commercial whole-slide imaging systems while maintaining reasonable accuracy, demonstrating that macroscopic features are sufficient for binary classification of stained breast tissue. A rapid low-cost imaging system capable of identifying healthy tissue not requiring human assessment could serve as a triage system for reducing caseloads and alleviating the significant strain on the current workforce.

Mesoscale standing wave imaging.

Standing wave (SW) microscopy is a method that uses an interference pattern to excite fluorescence from labelled cellular structures and produces high-resolution images of three-dimensional objects in a two-dimensional dataset. SW microscopy is performed with high-magnification, high-numerical aperture objective lenses, and while this results in high-resolution images, the field of view is very small. Here we report upscaling of this interference imaging method from the microscale to the mesoscale using the Mesolens, which has the unusual combination of a low-magnification and high-numerical aperture. With this method, we produce SW images within a field of view of 4.4 mm × 3.0 mm that can readily accommodate over 16,000 cells in a single dataset. We demonstrate the method using both single-wavelength excitation and the multi-wavelength SW method TartanSW. We show application of the method for imaging of fixed and living cells specimens, with the first application of SW imaging to study cells under flow conditions.

Uncovering the cytotoxic effects of air pollution with multi-modal imaging of in vitro respiratory models.

Annually, an estimated seven million deaths are linked to exposure to airborne pollutants. Despite extensive epidemiological evidence supporting clear associations between poor air quality and a range of short- and long-term health effects, there are considerable gaps in our understanding of the specific mechanisms by which pollutant exposure induces adverse biological responses at the cellular and tissue levels. The development of more complex, predictive, in vitro respiratory models, including two- and three-dimensional cell cultures, spheroids, organoids and tissue cultures, along with more realistic aerosol exposure systems, offers new opportunities to investigate the cytotoxic effects of airborne particulates under controlled laboratory conditions. Parallel advances in high-resolution microscopy have resulted in a range of in vitro imaging tools capable of visualizing and analysing biological systems across unprecedented scales of length, time and complexity. This article considers state-of-the-art in vitro respiratory models and aerosol exposure systems and how they can be interrogated using high-resolution microscopy techniques to investigate cell-pollutant interactions, from the uptake and trafficking of particles to structural and functional modification of subcellular organelles and cells. These data can provide a mechanistic basis from which to advance our understanding of the health effects of airborne particulate pollution and develop improved mitigation measures.

Development of a Highly Sensitive Hybrid LC/MS Assay for the Quantitative Measurement of CTLA-4 in Human T Cells.

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a check point protein expressed on the surface of T cells and plays a central role in regulating the immune response. In recent years, CTLA-4 has become a popular target for cancer immunotherapy in which blocking CTLA-4 can restore T-cell function and enhance the immune response against cancer. Currently, there are many CTLA-4 inhibitors in a variety of modalities, including cell therapies, which are being developed in both preclinical and clinical stages to further harness the potential of the target for the treatment of certain types of cancer. In drug discovery research, measuring the level of CTLA-4 in T cells is important for drug discovery and development because it provides key information for quantitative assessment of the pharmacodynamics, efficacy, and safety of the CTLA-4-based therapies. However, to our best knowledge, there is still no report of a sensitive, specific, accurate, and reliable assay for CTLA-4 measurement. In this work, an LC/MS-based method was developed to measure CTLA-4 in human T cells. The assay demonstrated high specificity with an LLOQ of 5 copies of CTLA-4 per cell when using 2.5 million T cells for analysis. As shown in the work, the assay was successfully used to measure CTLA-4 levels in subtype T-cell samples from individual healthy subjects. The assay could be applied in supporting the studies of CTLA-4-based cancer therapies.

Understanding the concept of trust and other factors related to COVID-19 vaccine intentions among Black/African American older adults prior to vaccine development.

Background: Black/African Americans are receiving COVID-19 vaccines at much lower rates than whites. However, research is still evolving that explains why these vaccination rates are lower. The aim of this study was to examine the effects of the pandemic among older Black/African Americans, with an emphasis on trust and vaccine intention prior to vaccine development. Methods: Data were collected between July and September 2020 from 8 virtual focus groups in Detroit, MI and San Francisco Bay Area, CA with 33 older African Americans and 11 caregivers of older African Americans with cognitive impairment, supplemented by one virtual meeting with the project's Community Advisory Board. Inductive/deductive content analysis was used to identify themes. Results: Five major themes influenced the intention to be vaccinated: uncertainty, systemic abandonment, decrease in trust, resistance to vaccines, and opportunities for vaccination. The last theme, opportunities for vaccination, emerged as a result of interaction with our CAB while collecting project data after the vaccines were available which provided additional insights about potential opportunities that would promote the uptake of COVID-19 vaccination among older Black/African Americans. The results also include application of the themes to a multi-layer framework for understanding precarity and the development of an Integrated Logic Model for a Public Health Crisis. Conclusions: These findings suggest that trust and culturally relevant information need to be addressed immediately to accelerate vaccine uptake among older Black/African Americans. New initiatives are needed to foster trust and address systemic abandonment from all institutions. In addition, culturally relevant public health campaigns about vaccine uptake are needed. Thus, systemic issues need immediate attention to reduce health disparities associated with COVID-19.

Microscope studies of symptomless growth of Botrytis cinerea in Lactuca sativa and Arabidopsis thaliana.

The grey mould pathogen Botrytis cinerea forms systemic associations in some hosts, spreading into plant organs produced a considerable time after initial infection. These infections may have no macroscopic symptoms during much of the hosts' lifetime and are at least partially within the host tissue. The aim of the studies reported here was to locate and visualize these infections at a cellular level in Lactuca sativa (lettuce) and Arabidopsis thaliana. Symptomless but infected plants were produced by dry spore inoculation of plants growing in conditions previously shown to result in fungal spread from the initial inoculation site to newly developing plant organs. Tissue taken from inoculated plants was examined using confocal laser scanning microscopy. Two B. cinerea isolates were used: B05.10 and its GFP-labelled derivative Bcgfp1-3. Spore germination on leaf surfaces was followed by development of subcuticular inclusions and plant cell damage in single infected epidermal cells and sometimes a few nearby cells. Sparsely branched long hyphae arose and spread from the inclusions, mostly on the outer surface of the epidermal layer but occasionally below the cuticle or epidermal cells, where further inclusions formed. This was consistent with the pattern in time of recovery of B. cinerea from surface-sterilized leaf tissue. In the late symptomless phase, mycelium arising from internal fungal inclusions formed mycelial networks on the surface of leaves. Symptomless exterior mycelium grew on the roots in A. thaliana.

Single-molecule and super-resolved imaging deciphers membrane behavior of onco-immunogenic CCR5.

The ability of tumors to establish a pro-tumorigenic microenvironment is an important point of investigation in the search for new therapeutics. Tumors form microenvironments in part by the "education" of immune cells attracted via chemotactic axes such as that of CCR5-CCL5. Further, CCR5 upregulation by cancer cells, coupled with its association with pro-tumorigenic features such as drug resistance and metastasis, has suggested CCR5 as a therapeutic target. However, with several conformational "pools" being reported, phenotypic investigations must be capable of unveiling conformational heterogeneity. Addressing this challenge, we performed super-resolution structured illumination microscopy (SIM) and single molecule partially TIRF-coupled HILO (PaTCH) microscopy of CCR5 in fixed cells. SIM data revealed a non-random spatial distribution of CCR5 assemblies, while Intensity-tracking of CCR5 assemblies from PaTCH images indicated dimeric sub-units independent of CCL5 perturbation. These biophysical methods can provide important insights into the structure and function of onco-immunogenic receptors and many other biomolecules.

Listeria Monocytogenes Septicemia in the Setting of an Ulcerative Colitis Flare.

A 51-year-old patient with a history of ulcerative colitis was admitted after three days of bloody diarrhea and abdominal pain. The patient had been trialing different immunosuppressive therapies over the past year. An acute flare of ulcerative colitis was confirmed, and our patient began to improve upon IV methylprednisolone. Blood cultures on admission were positive for Listeria monocytogenes. IV ampicillin and gentamicin were begun for treatment. Upon discharge, the patient was switched to high-dose amoxicillin. This case report shows that Listeria can be a cause of septicemia in ulcerative colitis patients undergoing immunosuppressive therapy.

Design, Synthesis, and Physicochemical Studies of Configurationally Stable ß-Carboline Atropisomers.

Axially chiral atropisomers have energetic barriers to rotation, ΔGrot, that prevent racemization of the respective enantiomers. We used computational modeling to develop a suite of 10 bio-inspired 1-aryl-ß-carbolines with varying ΔGrot, from which a strong structure-activity relationship was observed for 2-substituted-1-naphthyl substituents. We then synthesized two of these atropisomers, 1d and 1f, by a four-step racemic synthesis and resolved the enantiomers via chiral chromatography. Racemization studies revealed experimental ΔGrot values of 39.5 and 33.0 kcal/mol for 1d and 1f, respectively, which were consistent with our computational results. These atropisomers exhibited long half-lives, which allowed for their physicochemical characterization and stereochemical assignment via UV-vis spectroscopy, fluorescence spectroscopy, electronic circular dichroism, and vibrational circular dichroism.

Time-Dependent Studies of Oxaliplatin and Other Nucleolar Stress-Inducing Pt(II) Derivatives.

The properties of small molecule Pt(II) compounds that drive specific cellular responses are of interest due to their broad clinical use as chemotherapeutics as well as to provide a better mechanistic understanding of bioinorganic processes. The chemotherapeutic compound cisplatin causes cell death through DNA damage, while oxaliplatin may induce cell death through inhibition of ribosome biogenesis, also referred to as nucleolar stress induction. Previous work has found a subset of oxaliplatin derivatives that cause nucleolar stress at 24 h drug treatment. Here we report that these different Pt(II) derivatives exhibit a range of rates and degrees of global nucleolar stress induction as well as inhibition of rRNA transcription. Potential explanations for these variations include both the ring size and stereochemistry of the non-aquation-labile ligand. We observe that Pt(II) compounds containing a 6-membered ring show faster onset and a higher overall degree of nucleolar stress than those containing a 5-membered ring, and that compounds having the 1R,2R-stereoisomeric conformation show faster onset and a higher overall degree of stress than those having the 1S,2S-conformation. Pt(II) cellular accumulation and cellular Pt(II)-DNA adduct formation did not correlate with nucleolar stress induction, indicating that the effect is not due to global interactions. Together these results suggest that Pt(II) compounds induce nucleolar stress through a mechanism that likely involves one or a few key intermolecular interactions.

Field application of Bacillus subtilis and Aureobasidium pullulans to reduce Monilinia laxa post-harvest rot on cherry.

Brown rot caused by Monilinia spp. is one of the most important diseases in stone fruits worldwide. Latent infections of fruit by the pathogen often manifest once the fruit is ripe, leading to post-harvest rots. Two microbial strains (Bacillus subtilis -B91 and Aureobasidium pullulans - Y126) have shown antagonistic properties against M. laxa in previous studies. This study assessed the reduction in post-harvest rot of cherry by M. laxa when the two biocontrol (BCAs) strains were applied pre-harvest under field conditions to fruit artificially inoculated with M. laxa. The experiment was carried out for two consecutive years in cherry orchards in Kent. When applied pre-harvest, both strains (B91 and Y126) reduced the incidence of post-harvest rots by 30% - 60%. This promising result helps towards the commercialisation of the two strains, which would reduce reliance on fungicides in commercial cherry production. Supplementary Information: The online version contains supplementary material available at 10.1007/s10658-022-02508-8.