Protein phosphatases regulate the formation of Müller glia-derived progenitor cells in the chick retina.

Different kinase-dependent cell signaling pathways are known to play important roles in glia-mediated neuroprotection and reprogramming of Müller glia (MG) into Müller glia-derived progenitor cells (MGPCs) in the retina. However, very little is known about the phosphatases that regulate kinase-dependent signaling in MG. Using single-cell RNA-sequencing (scRNA-seq) databases, we investigated patterns of expression of Dual Specificity Phosphatases (DUSP1/6) and other protein phosphatases in normal and damaged chick retinas. We found that DUSP1, DUSP6, PPP3CB, PPP3R1 and PPPM1A/B/D/E/G are widely expressed by many types of retinal neurons and are dynamically expressed by MG and MGPCs in retinas during the process of reprogramming. We find that inhibition of DUSP1/6 and PP2C phosphatases enhances the formation of proliferating MGPCs in damaged retinas and in retinas treated with insulin and FGF2 in the absence of damage. By contrast, inhibition of PP2B phosphatases suppressed the formation of proliferating MGPCs, but increased numbers of proliferating MGPCs in undamaged retinas treated with insulin and FGF2. In damaged retinas, inhibition of DUSP1/6 increased levels of pERK1/2 and cFos in MG whereas inhibition of PP2B's decreased levels of pStat3 and pS6 in MG. Analyses of scRNA-seq libraries identified numerous differentially activated gene modules in MG in damaged retinas versus MG in retinas treated with insulin+FGF2 suggesting significant differences in kinase-dependent signaling pathways that converge on the formation of MGPCs. Inhibition of phosphatases had no significant effects upon numbers of dying cells in damaged retinas. We conclude that the activity of different protein phosphatases acting through retinal neurons and MG "fine-tune" the cell signaling responses of MG in damaged retinas and during the reprogramming of MG into MGPCs.

A vein bypass first versus a best endovascular treatment first revascularisation strategy for patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal revascularisation procedure to restore limb perfusion (BASIL-2): an open-label, randomised, multicentre, phase 3 trial.

BACKGROUND: Chronic limb-threatening ischaemia is the severest manifestation of peripheral arterial disease and presents with ischaemic pain at rest or tissue loss (ulceration, gangrene, or both), or both. We compared the effectiveness of a vein bypass first with a best endovascular treatment first revascularisation strategy in terms of preventing major amputation and death in patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. METHODS: Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL)-2 was an open-label, pragmatic, multicentre, phase 3, randomised trial done at 41 vascular surgery units in the UK (n=39), Sweden (n=1), and Denmark (n=1). Eligible patients were those who presented to hospital-based vascular surgery units with chronic limb-threatening ischaemia due to atherosclerotic disease and who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. Participants were randomly assigned (1:1) to receive either vein bypass (vein bypass group) or best endovascular treatment (best endovascular treatment group) as their first revascularisation procedure through a secure online randomisation system. Participants were excluded if they had ischaemic pain or tissue loss considered not to be primarily due to atherosclerotic peripheral artery disease. Most vein bypasses used the great saphenous vein and originated from the common or superficial femoral arteries. Most endovascular interventions comprised plain balloon angioplasty with selective use of plain or drug eluting stents. Participants were followed up for a minimum of 2 years. Data were collected locally at participating centres. In England, Wales, and Sweden, centralised databases were used to collect information on amputations and deaths. Data were analysed centrally at the Birmingham Clinical Trials Unit. The primary outcome was amputation-free survival defined as time to first major (above the ankle) amputation or death from any cause measured in the intention-to-treat population. Safety was assessed by monitoring serious adverse events up to 30-days after first revascularisation. The trial is registered with the ISRCTN registry, ISRCTN27728689. FINDINGS: Between July 22, 2014, and Nov 30, 2020, 345 participants (65 [19%] women and 280 [81%] men; median age 72·5 years [62·7-79·3]) with chronic limb-threatening ischaemia were enrolled in the trial and randomly assigned: 172 (50%) to the vein bypass group and 173 (50%) to the best endovascular treatment group. Major amputation or death occurred in 108 (63%) of 172 patients in the vein bypass group and 92 (53%) of 173 patients in the best endovascular treatment group (adjusted hazard ratio [HR] 1·35 [95% CI 1·02-1·80]; p=0·037). 91 (53%) of 172 patients in the vein bypass group and 77 (45%) of 173 patients in the best endovascular treatment group died (adjusted HR 1·37 [95% CI 1·00-1·87]). In both groups the most common causes of morbidity and death, including that occurring within 30 days of their first revascularisation, were cardiovascular (61 deaths in the vein bypass group and 49 in the best endovascular treatment group) and respiratory events (25 deaths in the vein bypass group and 23 in the best endovascular treatment group; number of cardiovascular and respiratory deaths were not mutually exclusive). INTERPRETATION: In the BASIL-2 trial, a best endovascular treatment first revascularisation strategy was associated with a better amputation-free survival, which was largely driven by fewer deaths in the best endovascular treatment group. These data suggest that more patients with chronic limb-threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion should be considered for a best endovascular treatment first revascularisation strategy. FUNDING: UK National Institute of Health Research Health Technology Programme.

Editor's Choice - Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL) Prospective Cohort Study and the Generalisability of the BASIL-2 Randomised Controlled Trial.

OBJECTIVE: The Bypass versus Angioplasty in Severe Ischaemia of the Leg-2 (BASIL-2) randomised controlled trial has shown that, for patients with chronic limb threatening ischaemia (CLTI) who require an infrapopliteal (IP) revascularisation a vein bypass (VB) first revascularisation strategy led to a 35% increased risk of major amputation or death when compared with a best endovascular treatment (BET) first revascularisation strategy. The study aims are to place the BASIL-2 trial within the context of the CLTI patient population as a whole and to investigate the generalisability of the BASIL-2 outcome data. METHODS: This was an observational, single centre prospective cohort study. Between 24 June 2014 and 31 July 2018, the BASIL Prospective Cohort Study (PCS) was performed which used BASIL-2 trial case record forms to document the characteristics, initial and subsequent management, and outcomes of 471 consecutive CLTI patients admitted to an academic vascular centre. Ethical approval was obtained, and all patients provided fully informed written consent. Follow up data were censored on 14 December 2022. RESULTS: Of the 238 patients who required an infrainguinal revascularisation, 75 (32%) had either IP bypass (39 patients) or IP BET (36 patients) outside BASIL-2. Seventeen patients were initially randomised to BASIL-2. A further three patients who did not have an IP revascularisation as their initial management were later randomised in BASIL-2. Therefore, 95/471 (20%) of patients had IP revascularisation (16% outside, 4% inside BASIL-2). Differences in amputation free survival, overall survival, and limb salvage between IP bypass and IP BET performed outside BASIL-2 were not subject to hypothesis testing due to the small sample size. Reasons for non-randomisation into the trial were numerous, but often due to anatomical and technical considerations. CONCLUSION: CLTI patients who required an IP revascularisation procedure and were subsequently randomised into BASIL-2 accounted for a small subset of the CLTI population as a whole. For a wide range of patient, limb, anatomical and operational reasons, most patients in this cohort were deemed unsuitable for randomisation in BASIL-2. The results of BASIL-2 should be interpreted in this context.

Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 Trial: Analysis of the Timing and Causes of Death in Participants Randomised to an Infrapopliteal Vein Bypass or Best Endovascular Treatment First Revascularisation Strategy.

OBJECTIVE: The Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 trial enrolled participants with chronic limb threatening ischaemia who required an infrapopliteal, with or without a femoropopliteal, revascularisation procedure to restore limb perfusion. Participants randomised to a vein bypass (VB) first revascularisation strategy were over one third more likely than those randomised to a best endovascular treatment (BET) first revascularisation strategy to die from any cause during a median follow up of 40.0 (interquartile range 20.9, 60.6) months. The aim of the present study was to describe the timing and causes of death in BASIL-2 as a first step towards trying to better understand why randomisation to a VB first revascularisation strategy was associated with this excess mortality. METHODS: A 10 person international panel comprising vascular and endovascular surgeons as well as vascular interventional radiologists, who had all been principal investigators in BASIL-2, took part in a modified Delphi consensus exercise to adjudicate the primary cause of death and, in particular, whether the cause was primarily cardiac or non-cardiac. RESULTS: In 151 of 168 deaths (89.9%), the Delphi panel achieved a consensus regarding the cause of death being probably cardiac or non-cardiac. In the BET group, 16 of 77 deaths (21%) were classified as probably cardiac compared with 32 of 91 (35%) in the VB group (unadjusted subdistribution hazard ratio 2.16, 95% confidence interval [CI] 1.20 - 3.87; unadjusted cause specific hazard ratio 2.15, 95% CI 1.19 - 3.90). At the point of randomisation, 64 of 344 (18.6%), 40 of 342 (11.7%), and 37 of 344 (10.8%) participants had a previous myocardial infarction (MI), percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG), respectively. There was no evidence of varying treatment effects for cause of death in subgroup analyses of previous PCI, CABG, or MI. CONCLUSION: The excess mortality observed in the VB first revascularisation strategy group in BASIL-2 was largely due to deaths that were adjudicated by the Delphi panel as probably primarily cardiac. These excess cardiac deaths were observed throughout follow up and there was no evidence of non-proportional hazards. Further work is ongoing to try to better understand the reasons for these findings.

The impact of a hospital-based special care unit on behavioural and psychological symptoms in older people living with dementia.

BACKGROUND: Hospital patients with behavioural and psychological symptoms of dementia (BPSD) are vulnerable to a range of adverse outcomes. Hospital-based Special Care Units (SCUs) are secure dementia-enabling environments providing specialised gerontological care. Due to a scarcity of research, their value remains unconfirmed. OBJECTIVE: To compare hospital based SCU management of BPSD with standard care. DESIGN: Single-case multiple baseline design. SETTING AND PARTICIPANTS: One-hundred admissions to an 8-bed SCU over 2 years in a large Australian public hospital. METHODS: Repeated measures of BPSD severity were undertaken prospectively by specialist dementia nurses for patients admitted to a general ward (standard care) and transferred to the SCU. Demographic and other clinical data, including diagnoses, medication use, and care-related outcomes were obtained from medical records retrospectively. Analysis used multilevel models to regress BPSD scores onto care-setting outcomes, adjusting for time and other factors. RESULTS: When receiving standard care, patients' BPSD severity was 6.8 (95% CI 6.04-7.64) points higher for aggression, 15.6 (95% CI 13.90-17.42) points higher for the neuropsychiatric inventory, and 5.8 (95% CI 5.14-6.50) points higher for non-aggressive agitation compared to SCU. Patients receiving standard care also experienced increased odds for patient-to-nurse violence (OR 2.61, 95% CI 1.67-4.09), security callouts (OR 5.39 95% CI 3.40-8.52), physical restraint (OR 17.20, 95% CI 7.94-37.25) and antipsychotic administration (OR 3.41, 95% CI 1.60-7.24). CONCLUSION: Clinically significant reductions in BPSD and psychotropic administration were associated with SCU care relative to standard ward care. These results suggest more robust investigation of hospital SCUs, and dementia-enabling design are warranted.

It's Not Just: Evaluation of a Media Campaign to Motivate Action Around Targeting of Menthol Tobacco in Black Communities.

Introduction: For more than 60 years, tobacco companies have aggressively marketed menthol tobacco products in Black communities. In 2021, New York State Department of Health-funded grantees launched a media campaign aimed toward civically engaged New York adults to educate and mobilize community action to prevent targeted marketing of menthol tobacco. This study examined audience reactions to the campaign and associations between campaign awareness and key outcomes. Methods: Following campaign implementation, we administered 2 online, cross-sectional surveys to 2,000 civically engaged New York adults to assess campaign awareness, audience reactions, and campaign-related attitudes and behaviors. We examined sociodemographic differences in audience reactions and assessed multivariate associations between campaign awareness and key outcomes. Results: Overall, 40% of respondents were aware of the campaign. Perceived advertisement (ad) effectiveness was higher among Black, Hispanic, and nonsmoking respondents and those aware of the campaign. Negative reactions to ads were higher at wave 1, among non-Hispanic White and male respondents, and among current smokers. Campaign awareness was positively associated with campaign-related beliefs. The association between campaign awareness and support for a menthol ban varied by survey wave and race, with positive associations at wave 2 and among non-Hispanic White respondents only. Among wave 2 respondents only, campaign awareness was positively associated with actions to reduce the targeting of menthol in Black communities. Conclusion: Media campaigns can play an important role in raising awareness of menthol tobacco product targeting in Black communities and building public support for local and statewide menthol restrictions that may be implemented before federal product standards are in place.

Opportunities and challenges with transitioning to non-lethal sampling of wild fish for microbiome research.

The microbial communities of fish are considered an integral part of maintaining the overall health and fitness of their host. Research has shown that resident microbes reside on various mucosal surfaces, such as the gills, skin, and gastrointestinal tract, and play a key role in various host functions, including digestion, immunity, and disease resistance. A second, more transient group of microbes reside in the digesta, or feces, and are primarily influenced by environmental factors such as the host diet. The vast majority of fish microbiome research currently uses lethal sampling to analyse any one of these mucosal and/or digesta microbial communities. The present paper discusses the various opportunities that non-lethal microbiome sampling offers, as well as some inherent challenges, with the ultimate goal of creating a sound argument for future researchers to transition to non-lethal sampling of wild fish in microbiome research. Doing so will reduce animal welfare and population impacts on fish while creating novel opportunities to link host microbial communities to an individual's behavior and survival across space and time (e.g., life-stages, seasons). Current lethal sampling efforts constrain our ability to understand the mechanistic ecological consequences of variation in microbiome communities in the wild. Transitioning to non-lethal sampling will open new frontiers in ecological and microbial research.

Chromatin access regulates the formation of Müller glia-derived progenitor cells in the retina.

Chromatin access and epigenetic control over gene expression play important roles in regulating developmental processes. However, little is known about how chromatin access and epigenetic gene silencing influence mature glial cells and retinal regeneration. Herein, we investigate the expression and functions of S-adenosylhomocysteine hydrolase (SAHH; AHCY) and histone methyltransferases (HMTs) during the formation of Müller glia (MG)-derived progenitor cells (MGPCs) in the chick and mouse retinas. In chick, AHCY, AHCYL1 and AHCYL2, and many different HMTs are dynamically expressed by MG and MGPCs in damaged retinas. Inhibition of SAHH reduced levels of H3K27me3 and potently blocks the formation of proliferating MGPCs. By using a combination of single cell RNA-seq and single cell ATAC-seq, we find significant changes in gene expression and chromatin access in MG with SAHH inhibition and NMDA-treatment; many of these genes are associated with glial and neuronal differentiation. A strong correlation across gene expression, chromatin access, and transcription factor motif access in MG was observed for transcription factors known to convey glial identity and promote retinal development. By comparison, in the mouse retina, inhibition of SAHH has no influence on the differentiation of neuron-like cells from Ascl1-overexpressing MG. We conclude that in the chick the activity of SAHH and HMTs are required for the reprogramming of MG into MGPCs by regulating chromatin access to transcription factors associated with glial differentiation and retinal development.

Reducing rural isolation through music: telehealth music therapy for community dwelling people living with dementia and their family caregivers in rural Ireland.

INTRODUCTION: Since the outset of COVID-19, we have become more reliant on technology to stay connected to others. Notable benefits of telehealth have been observed, including increased access to health and community support services for community dwelling people living with dementia and their family caregivers and diminishing barriers such as geographical location, mobility issues and increased cognitive decline. Music therapy is an evidence-based intervention for people living with dementia and has been proven to promote improved quality of life, increase social interaction and provide a form of meaningful communication and expression when language becomes difficult. This project is one of the first internationally to pilot telehealth music therapy for this population. METHODS: This mixed methods action research project has six iterative phases of planning, research, action, evaluation, and monitoring. Public and Patient Involvement (PPI) has been sought from members of The Dementia Research Advisory Team at the Alzheimer Society of Ireland at all stages of the research process to ensure the research remains relevant and applicable to those with dementia. The presentation will briefly outline the phases of the project. RESULTS: Preliminary results from this ongoing research suggest that there is feasibility for telehealth music therapy to provide psychosocial support to this population. Collaboration with PPI contributors resulted in the following research priorities: (1) ensuring a person-centered approach; (2) advanced care planning using music; and (3) the signposting of music related supports for community dwelling people living with dementia. Music therapy is being piloted currently and preliminary results will be outlined. DISCUSSION: Telehealth music therapy has the potential to complement existing rural health and community services for people living with dementia, in particular addressing social isolation. Recommendations regarding the relevance of cultural and leisure pursuits on health and well-being of people living with dementia will be discussed, particularly the development of online access.

Procedural and 12-month in-hospital costs of primary infra-popliteal bypass surgery, infrapopliteal best endovascular treatment, and major lower limb amputation for chronic limb threatening ischemia.

OBJECTIVE: Chronic limb-threatening ischemia (CLTI) is a growing global problem due to the widespread use of tobacco and increasing prevalence of diabetes. Although the financial consequences are considerable, few studies have compared the relative cost-effectiveness of different CLTI management strategies. The Bypass vs Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 trial is randomizing patients with CLTI to primary infrapopliteal (IP) vein bypass surgery (BS) or best endovascular treatment (BET) and includes a comprehensive within-trial cost-utility analysis. The aim of this study is to compare over a 12-month time horizon, the costs of primary IP BS, IP best endovascular treatment (BET), and major limb major amputation (MLLA) to inform the BASIL-2 cost-utility analysis. METHODS: We compared procedural human resource (HR) costs and total in-hospital costs for the index admission, and over the following 12-months, in 60 consecutive patients undergoing primary IP BS (n = 20), IP BET (n = 20), or MLLA (10 transfemoral and 10 transtibial) for CLTI within the BASIL prospective cohort study. RESULTS: Procedural HR costs were greatest for BS (BS £2551; 95% confidence interval [CI], £1934-£2807 vs MLLA £1130; 95% CI, £1046-£1297 vs BET £329; 95% CI, £242-£390; P < .001, Kruskal-Wallis) due to longer procedure duration and greater staff requirement. With regard to the index admission, MLLA was the most expensive due to longer hospital stay (MLLA £13,320; 95% CI, £8986-£18,616 vs BS £8714; 95% CI, £6097-£11,973 vs BET £4813; 95% CI, £3529-£6097; P < .001, Kruskal-Wallis). The total cost of the index admission and in-hospital care over the following 12 months remained least for BET (MLLA £26,327; 95% CI, £17,653-£30,458 vs BS £20,401; 95% CI, £12,071-£23,926 vs BET £12,298; 95% CI, £6961-£15,439; P < .001, Kruskal-Wallis). CONCLUSIONS: Over a 12-month time horizon, MLLA and IP BS are more expensive than IP BET in terms of procedural HR costs and total in-hospital costs. These economic data, together with quality of life data from BASIL-2, will inform the calculation of incremental cost-effectiveness ratios for different CLTI management strategies within the BASIL-2 cost-utility analysis.

Thermal Burn Injury Generates Bioactive Microvesicles: Evidence for a Novel Transport Mechanism for the Lipid Mediator Platelet-Activating Factor (PAF) That Involves Subcellular Particles and the PAF Receptor.

Thermal burn injuries are an important environmental stressor that can result in considerable morbidity and mortality. The exact mechanism by which an environmental stimulus to skin results in local and systemic effects is an area of active research. One potential mechanism to allow skin keratinocytes to disperse bioactive substances is via microvesicle particles, which are subcellular bodies released directly from cellular membranes. Our previous studies have indicated that thermal burn injury of the skin keratinocyte in vitro results in the production of the lipid mediator platelet-activating factor (PAF). The present studies demonstrate that thermal burn injury to keratinocytes in vitro and human skin explants ex vivo, and mice in vivo generate microvesicle particles. Use of pharmacologic and genetic tools indicates that the optimal release of microvesicles is dependent upon the PAF receptor. Of note, burn injury-stimulated microvesicle particles do not carry appreciable protein cytokines yet contain high levels of PAF. These studies describe a novel mechanism involving microvesicle particles by which a metabolically labile bioactive lipid can travel from cells in response to environmental stimuli.

Reducing Recovery Times in Outpatient Liver Biopsies: Role of the GI Nurse.

This project is aimed to identify whether recovery times could be reduced in patients undergoing an outpatient liver biopsy. Liver biopsies are typically performed in a hospital setting, and many facilities require patients to recover for multiple hours, sometimes ranging from 4 to 6 hours. This can discourage the patient from undergoing the biopsy. Multiple studies have examined recovery times and determined patients can safely recover and be discharged within 1-2 hours post-liver biopsy. In this retrospective review, the data of 60 outpatients who underwent a liver biopsy from June to December 2020 were analyzed. Analysis included comparing vital signs and symptoms at the 2-hour recovery period and 4-hour discharge time also to see whether there were any hospital admissions 1 week post-liver biopsy. Descriptive statistics were utilized for the data collected in this study. Results demonstrated that after 2 hours, 55 (91.7%) patients had vital signs within safe parameters, pain less than 5 on a 10-point pain scale and denied any other symptoms. The remaining five patients (8.3%) did not meet discharge criteria at the 2-hour mark because of pain greater than 5 on the pain scale yet were still discharged safely at the 4-hour mark.

Whole-Genome Data from Curtobacterium flaccumfaciens pv. flaccumfaciens Strains Associated with Tan Spot of Mungbean and Soybean Reveal Diverse Plasmid Profiles.

Despite the substantial economic impact of Curtobacterium flaccumfaciens pv. flaccumfaciens on legume production worldwide, the genetic basis of its pathogenicity and potential host association is poorly understood. The production of high-quality reference genome assemblies of C. flaccumfaciens pv. flaccumfaciens strains associated with different hosts sheds light on the genetic basis of its pathogenic variability and host association. Moreover, the study of recent outbreaks of bacterial wilt and microevolution of the pathogen in Australia requires access to high-quality reference genomes that are sufficiently closely related to the population being studied within Australia. We provide the first genome assemblies of C. flaccumfaciens pv. flaccumfaciens strains associated with mungbean and soybean, which revealed high variability in their plasmid composition. The analysis of C. flaccumfaciens pv. flaccumfaciens genomes revealed an extensive suite of carbohydrate-active enzymes potentially associated with pathogenicity, including four carbohydrate esterases, 50 glycoside hydrolases, 23 glycosyl transferases, and a polysaccharide lyase. We also identified 11 serine peptidases, three of which were located within a linear plasmid, pCff119. These high-quality assemblies and annotations will provide a foundation for population genomics studies of C. flaccumfaciens pv. flaccumfaciens in Australia and for answering fundamental questions regarding pathogenicity factors and adaptation of C. flaccumfaciens pv. flaccumfaciens to various hosts worldwide and, at a broader scale, contribute to unraveling genomic features of gram-positive, xylem-inhabiting bacterial pathogens.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Oxysterol gradient generation by lymphoid stromal cells guides activated B cell movement during humoral responses.

7α,25-dihydroxycholesterol (7α,25-OHC) is a ligand for the G protein-coupled receptor EBI2; however, the cellular sources of this oxysterol are undefined. 7α,25-OHC is synthesized from cholesterol by the stepwise actions of two enzymes, CH25H and CYP7B1, and is metabolized to a 3-oxo derivative by HSD3B7. We showed that all three enzymes control EBI2 ligand concentration in lymphoid tissues. Lymphoid stromal cells were the main CH25H- and CYP7B1-expressing cells required for positioning of B cells, and they also mediated 7α,25-OHC inactivation. CH25H and CYP7B1 were abundant at the follicle perimeter, whereas CH25H expression by follicular dendritic cells was repressed. CYP7B1, CH25H, and HSD3B7 deficiencies each resulted in defective T cell-dependent plasma cell responses. These findings establish that CYP7B1 and HSD3B7, as well as CH25H, have essential roles in controlling oxysterol production in lymphoid tissues, and they suggest that differential enzyme expression in stromal cell subsets establishes 7α,25-OHC gradients required for B cell responses.

Solvent-Dependent Photophysics and Reactivity of Monomeric and Dimeric 4-Amino-1,8-Naphthalimides.

The solvent-dependent photophysics of two 4-amino-substituted 1,8-naphthalene imides (AIs) were studied using fluorescence spectroscopy and laser flash photolysis. The compounds were functionalized with water-soluble 2,2'(ethylenedioxy) diethylamine groups, yielding a monomer (AI3) and a dimer (AI4). The radiative and nonradiative singlet-state deactivation processes of AI3 and AI4 were quantified in 10 solvents and at different pH values. The fluorescence quantum yield for the AI4 dimer in water was more than 100× lower than in other solvents, or for the monomeric AI3. The enhanced nonradiative decay of aqueous solutions of dimeric AI4 is accompanied by biexponential decay kinetics, suggesting equilibration with a dark excited state. An oxygen-quenchable triplet state (T1) of AI3 was produced upon 416 nm excitation in both water and n-octanol. In water, the T1 state evolved into a long-lived transient that was unreactive toward oxygen or several electron donors. This species was not observed in n-octanol. The transient observed upon 416 nm excitation of AI4 in water was extremely weak. However, production of T1 in both AI3 and AI4 was evidenced by the photoinduced electron transfer to methyl viologen, albeit in low quantum yield (0.0503 and 0.00778 for AI3 and AI4, respectively). The photophysics and reactivity are consistent with the production of an intramolecular charge transfer (ICT) state that is stabilized in water. Significantly, this stabilization enhances nonradiative decay pathways, particularly in the AI4 dimer. The results indicate that the photochemistry of these compounds can be environmentally mediated, switching from radical- to triplet-initiated processes.

One Crop Disease, How Many Pathogens? Podosphaera xanthii and Erysiphe vignae sp. nov. Identified as the Two Species that Cause Powdery Mildew of Mungbean (Vigna radiata) and Black Gram (V. mungo) in Australia.

Powdery mildew is a significant threat to mungbean (Vigna radiata) and black gram (V. mungo) production across Australia and overseas. Although they have been present in Australia for at least six decades and are easily recognized in the field, the precise identification of the pathogens causing this disease has remained unclear. Our goal was to identify the powdery mildew species infecting mungbean, black gram, and wild mungbean (V. radiata ssp. sublobata) in Australia. The internal transcribed spacer (ITS) and large subunit sequences of the ribosomal DNA and/or morphology of 57 Australian specimens were examined. Mungbean and black gram were infected by two species: Podosphaera xanthii and a newly recognized taxon, Erysiphe vignae sp. nov. Wild mungbean was infected only with P. xanthii. Mungbean and black gram powdery mildew ITS sequences from China, India, and Taiwan revealed the presence of only P. xanthii on these crops despite controversial reports of an Erysiphe species on both crops in India. Sequence analyses indicated that the closest relative of E. vignae is E. diffusa, which infects soybean (Glycine max) and other plants. E. vignae did not infect soybean in cross-inoculation tests. In turn, E. diffusa from soybean infected black gram and provoked hypersensitive response in mungbean. The recognition of a second species, E. vignae, as another causal agent of mungbean and black gram powdery mildew in Australia may complicate plant breeding efforts and control of the disease with fungicide applications.

miR-199 plays both positive and negative regulatory roles in Xenopus eye development.

To investigate microRNA (miR) functions in early eye development, we asked whether eye field transcription factors (EFTFs) are targets of miR-dependent regulation in Xenopus embryos. Argonaute (AGO) ribonucleoprotein complexes, including miRs and targeted mRNAs, were coimmunoprecipitated from transgenic embryos expressing myc-tagged AGO under the control of the rax1 promoter; mRNAs for all EFTFs coimmunoprecipitated with Ago in late neurulae. Computational predictions of miR binding sites within EFTF 3'UTRs identified miR-199a-3p ("miR-199") as a candidate regulator of EFTFs, and miR-199 was shown to regulate rax1 in vivo. Targeted overexpression of miR-199 led to small eyes, a reduction in EFTF expression, and reduced cell proliferation. Inhibition of interactions between mir-199 and the rax1 3'UTR reversed the small eye phenotype. Although targeted knockdown of miR-199 left the eye field intact, it reduced optic cup outgrowth and disrupted eye formation. Computational identification of candidate miR-199 targets within the Xenopus transcriptome led to the identification of ptk7 as a candidate regulator. Targeted overexpression of ptk7 resulted in abnormal optic cup formation and a reduction or loss of eye development, recapitulating the range of eye phenotypes seen following miR-199 knockdown. Our results indicate that miR-199 plays both positive and negative regulatory roles in eye development.

Photochemistry of the Organoselenium Compound Ebselen: Direct Photolysis and Reaction with Active Intermediates of Conventional Reactive Species Sensitizers and Quenchers.

Ebselen (EBS), 2-phenyl-1,2-benzisoselenazol-3(2H)-one, is an organoselenium pharmaceutical with antioxidant and anti-inflammatory properties. Furthermore, EBS is an excellent scavenger of reactive oxygen species. This property complicates conventional protocols for sensitizing and quenching reactive species because of potential generation of active intermediates that quickly react with EBS. In this study, the photochemical reactivity of EBS was investigated in the presence of (1) 1O2 and •OH sensitizers [rose Bengal (RB), perinaphthanone, and H2O2] and (2) reactive species scavenging and quenching agents (sorbic acid, isopropanol, sodium azide, and tert-butanol) that are commonly employed to study photodegradation mechanisms and kinetics. The carbon analogue of EBS, namely, 2-phenyl-3H-isoindol-1-one, was included as a reference compound to confirm the impact of the selenium atom on EBS photochemical reactivity. EBS does not undergo acid dissociation, but pH-dependent kinetics were observed in RB-sensitized solutions, suggesting EBS reaction with active intermediates (3RB2-*, O2•-, and H2O2) that are not kinetically relevant for other compounds. In addition, the observed rate constant of EBS increased in the presence of sorbic acid, isopropanol, and sodium azide. These findings suggest that conventional reactive species sensitizers, scavengers, and quenchers need to be carefully applied to highly reactive organoselenium compounds to account for reactions that are typically slow for other organic contaminants.

Formation and Reaction Kinetics of Biradicals and Triplet States in a Series of Carboxylated 1,4,5,8-Naphthalene Diimides.

The singlet-state deactivation products in a series of alkyl carboxylate substituted 1,4,5,8-naphthalene diimide (NDI) compounds were characterized using fluorescence and phosphorescence spectroscopies, as well as nanosecond laser flash photolysis. The reactive intermediates were quantified as a function of the number of methylenes in the alkyl linker. Rate constants for photoinduced electron transfer (PET) to the singlet excited state of the NDIs varied from 1.2 × 1010 to 4.9 × 1010 s-1. The yield of the long-lived amino ketyl radical ranged from 15% to 60% in compounds having 4 to 1 intervening methylenes between the NDI chromophore and the covalently attached carboxylic acid. A predominantly triplet state was observed upon direct excitation of the compound having the slowest PET. This T1 state of the NDIs was reductively quenched by DABCO electron donor. The amino ketyl radical was unreactive toward electron donors but was found to react with the hydrogen atom donor ß-mercaptoethanol. The compounds comprise a novel class of long-wavelength and strongly absorbing UV-activated chromophores that generate carbon-centered biradicals via direct 355 nm excitation in the absence of a cosensitizer.

Spiritual Experiences of Long-Term Meditation Practitioners Diagnosed with Breast Cancer: An Interpretative Phenomenological Analysis Pilot Study.

The purpose of this study was to explore the spiritual experiences of long-term Brahma Kumaris Raja Yoga (a spiritually focused meditation practice) meditators who have been diagnosed with cancer and to understand how their long-term meditation practice influenced their ability to face the physical, emotional, and spiritual challenges of surviving cancer. Interpretative phenomenological analysis was used to investigate the lived experience of spirituality as described by three cancer survivors. Participants with a history of a cancer diagnosis were sought from the Brahma Kumaris Raja Yoga meditation centers across the USA. The participants were interviewed in an in-depth and open-ended manner. The interviews were audio-recorded, transcribed, and analyzed. Five super-ordinate themes were identified: positive state of mind, self-awareness, God's healing power, spiritual support, and spiritual growth. Among the 20 sub-themes that were generated, soul consciousness, awareness of eternity, lack of fear, being happy no matter what, and becoming an inspirational model were new themes that emerged in this study not previously identified in the current literature. Long-term, spiritually focused meditation practice was found to contribute to increased well-being and resilience for these three participants in the face of a cancer diagnosis and subsequent treatment challenges. The powerful awareness of seeing the self as a soul, a metaphysical energy distinct from the body, was a major source of spiritual strength and growth for these cancer survivors. Spiritually focused meditation practices appear to increase the emotional, physical, and spiritual well-being of cancer survivors, which could translate into better physiological outcomes (more research is required in this area). Such self-care practices could be integrated into overall treatment plans, which may reduce the emotional and financial cost of health care and thus benefit the nation at large.