Near-Unity All-Optical Modulation of Third-Harmonic Generation with a Fano-Resonant Dielectric Metasurface.

We demonstrate all-optical modulation with a near-unity contrast of nonlinear light generation in a dielectric metasurface. We study third-harmonic generation from silicon Fano-resonant metasurfaces excited by femtosecond pulses at 1480 nm wavelength. We modulate the metasurface resonance by free carrier excitation induced by absorption of an 800 nm pump pulse, leading to up to 93% suppression of third-harmonic generation. Modulation and recovery occur on (sub)picosecond time scales. According to the Drude model, the pump-induced refractive index change blue-shifts the metasurface resonance away from the generation pulse, causing a strong modulation of third-harmonic conversion efficiency. The principle holds great promise for spatiotemporal programmability of nonlinear light generation.

Ultrafast transient absorption spectra and kinetics of human blue cone visual pigment at room temperature.

The ultrafast photochemical reaction mechanism, transient spectra, and transition kinetics of the human blue cone visual pigment have been recorded at room temperature. Ultrafast time-resolved absorption spectroscopy revealed the progressive formation and decay of several metastable photo-intermediates, corresponding to the Batho to Meta-II photo-intermediates previously observed with bovine rhodopsin and human green cone opsin, on the picosecond to millisecond timescales following pulsed excitation. The experimental data reveal several interesting similarities and differences between the photobleaching sequences of bovine rhodopsin, human green cone opsin, and human blue cone opsin. While Meta-II formation kinetics are comparable between bovine rhodopsin and blue cone opsin, the transition kinetics of earlier photo-intermediates and qualitative characteristics of the Meta-I to Meta-II transition are more similar for blue cone opsin and green cone opsin. Additionally, the blue cone photo-intermediate spectra exhibit a high degree of overlap with uniquely small spectral shifts. The observed variation in Meta-II formation kinetics between rod and cone visual pigments is explained based on key structural differences.

The Prognostic Significance of Tumoral Melanosis.

BACKGROUND: Tumoral melanosis (TM) is a histological term to describe a nodular aggregation of macrophages containing melanin pigment (melanophages) that is devoid of viable melanocytes. It is most often identified in skin, where it may be appreciated clinically as a pigmented lesion; however, it can also be found in other organs such as lymph nodes. The presence of TM is usually thought to signify the presence of a regressed melanoma or other pigmented tumor. Until recently, it was a relatively uncommon finding; however, with the use of effective systemic therapies against melanoma, its occurrence in histological specimens is more frequent. METHODS: We identified and reviewed all histopathological diagnoses of TM at any organ site reported at a single institution from 2006 to 2018. TM cases were paired with non-TM cases of cutaneous melanoma through propensity score matching at a 1:2 ratio, and their survival outcomes were compared. The clinical outcomes examined included recurrence-free survival (RFS), distant disease-free survival (DDFS), melanoma-specific survival (MSS), and overall survival (OS). RESULTS: TM was reported in 79 patients. Their median age was 65 years (range 22-88), with a 2:1 male predominance (51 out of 79, 65%). The most common organ involved was the skin (67%), with a third of all cases localized to a lower limb (36%). TM had a strong association with the presence of melanoma (91%) and regression at other sites of melanoma (54%), suggesting that it is part of a systemic immune response against melanoma. Most patients with TM either previously or subsequently developed histologically confirmed melanoma in the same anatomical region as the TM (89%). Thirty-five TM patients were matched with 70 non-TM cases. Patients with melanoma who developed TM without prior regional or systemic therapy showed improved MSS (p = 0.03), whereas no statistically significant differences were observed in terms of RFS, DDFS, and OS. CONCLUSIONS: TM usually occurs in the context of a previous or subsequent cutaneous melanoma and is associated with improved MSS. It is important that TM is recognized by pathologists and documented in pathology reports.

Environmental Determinants of Health-Time to Redefine the Social History?

This Viewpoint discusses how increasing climate change and other environmental hazards contribute to greater adverse health effects, particularly for socially vulnerable populations, and calls for improved gathering of social and environmental history data and risk assessment in routine patient encounters.

Long-term remission of Hailey-Hailey disease by Er:YAG ablative laser therapy.

BACKGROUND: Hailey-Hailey disease (HHD) is a rare genetic therapy-resistant blistering disease with great disease burden. Treatment is currently focused on symptomatic relief. Er:YAG ablative laser therapy is a therapeutic modality with promising results, though evidence is currently scarce. OBJECTIVE: To analyse the effect of Er:YAG ablative laser therapy on clinical remission of erosive plaques in HHD and on patient's quality of life (QoL). METHODS: In this observational study eight patients were included and 77 erosive plaques were treated once only by Er:YAG laser and assessed for clinical remission. QoL was evaluated by obtaining Skindex-29 and DLQI questionnaires before laser therapy, 6 weeks and 3 years after laser therapy. Skin biopsies were taken to evaluate the depth of laser ablation. The intercellular distance between keratinocytes, the number of desmosomes and intermediate filament distribution were studied by electron microscopy before and after laser therapy and in clinically uninvolved skin and were compared to subjects without HHD. RESULTS: One single Er:YAG laser ablation to mid-dermis resulted in complete remission of 97.4% of HHD plaques (75/77) after median 38 months (range 7-63 months) and significantly improved QoL. Laser therapy restored the number of desmosomes, decreased intercellular distance and diminished perinuclear retraction of keratin filaments to a level comparable to the patient's clinically uninvolved skin. After laser ablation, the skin showed significantly fewer ultrastructural aberrations compared to the patient's clinically uninvolved skin and rather resembled the skin of healthy control individuals. CONCLUSION: One single Er:YAG laser treatment resulted in long-term remission of HHD and significantly improved QoL. Our findings support a greater role for ablative laser surgery in the management of this recalcitrant disorder.

What is known about suicide prevention gatekeeper training and directions for future research.

INTRODUCTION: Suicide prevention training that teaches skills to support a person experiencing thoughts of suicide and create community support networks, often termed, "gatekeeper" training (GKT), has been a longstanding pillar of international, national, and local suicide prevention efforts. GKT aims to improve knowledge, attitudes, and self-efficacy in identifying individuals at risk for suicide, hopefully enhancing one's willingness and ability to intervene with a person experiencing a crisis. However, little is known about GKT's effectiveness in creating the essential behavior change (e.g., increase in intervening behaviors) it sets out to accomplish. METHODS: This paper explores the history and theoretical background of GKT, reviews the current state of research on GKT, and provides framing and recommendations for next steps to advance research and practice around GKT. RESULTS & CONCLUSION: Through positioning GKT appropriately within the field of suicide prevention, we argue that the field of suicide prevention needs more rigorous research around GKT that includes long-term follow-up data on usage of skills learned during training, data on outcomes of those who have received an intervention from a trained gatekeeper, and the integration of implementation science to further our understanding of which trainings are appropriate for which helpers.

Next-generation cell-penetrating antibodies for tumor targeting and RAD51 inhibition.

Monoclonal antibody therapies for cancer have demonstrated extraordinary clinical success in recent years. However, these strategies are thus far mostly limited to specific cell surface antigens, even though many disease targets are found intracellularly. Here we report studies on the humanization of a full-length, nucleic acid binding, monoclonal lupus-derived autoantibody, 3E10, which exhibits a novel mechanism of cell penetration and tumor specific targeting. Comparing humanized variants of 3E10, we demonstrate that cell uptake depends on the nucleoside transporter ENT2, and that faster cell uptake and superior in vivo tumor targeting are associated with higher affinity nucleic acid binding. We show that one human variant retains the ability of the parental 3E10 to bind RAD51, serving as a synthetically lethal inhibitor of homology-directed repair in vitro. These results provide the basis for the rational design of a novel antibody platform for therapeutic tumor targeting with high specificity following systemic administration.

Slamf7 is dispensable in mouse models of acute lung injury.

Slamf7 is expressed by monocyte-derived macrophages recruited to the lungs during injury. Whole-body and macrophage-specific knockouts of Slamf7 had no effect on the degree of inflammation in three mouse models of acute lung injury. https://bit.ly/3KgTJg1.

Genetic architecture reconciles linkage and association studies of complex traits.

Linkage studies have successfully mapped loci underlying monogenic disorders, but mostly failed when applied to common diseases. Conversely, genome-wide association studies (GWASs) have identified replicable associations between thousands of SNPs and complex traits, yet capture less than half of the total heritability. In the present study we reconcile these two approaches by showing that linkage signals of height and body mass index (BMI) from 119,000 sibling pairs colocalize with GWAS-identified loci. Concordant with polygenicity, we observed the following: a genome-wide inflation of linkage test statistics; that GWAS results predict linkage signals; and that adjusting phenotypes for polygenic scores reduces linkage signals. Finally, we developed a method using recombination rate-stratified, identity-by-descent sharing between siblings to unbiasedly estimate heritability of height (0.76 ± 0.05) and BMI (0.55 ± 0.07). Our results imply that substantial heritability remains unaccounted for by GWAS-identified loci and this residual genetic variation is polygenic and enriched near these loci.

Supporting mental health in farming communities where and when it is needed most: A longitudinal analysis of risk and protective factors.

The cyclical nature of agriculture exposes farmers to challenges that vary over time, influenced by a myriad of external factors beyond their control. This longitudinal study aimed to examine mental health trajectories for Western Australian farmers over a 12 month period, and determine associations with key risk and protective factors. Farmers and farm residents (N = 125) completed an online survey at three timepoints (baseline, 6 months and 12 months) that assessed anxiety, depression, stress, farming stressors, coping strategies, sense of belonging and social supports. Survey timing coincided with periods of harvest and seeding. Risk factors associated with poorer mental health among farmers included a range of dysfunctional and emotion coping strategies, family/relationship stressors, financial/external stressors and daily stressors. Protective factors included sense of belonging and social support. Stress was found to change over time and family/relationship stressors and financial/external stressors at baseline were found to moderate anxiety and stress at 6 months and 12 months. Addressing factors associated with poor mental health trajectories and bolstering factors that are protective for mental health over time will aid clinical and community services in tailoring their services to meet the needs of farmers.

Tumor-specific antigen delivery for T-cell therapy via a pH-sensitive peptide conjugate.

Identifying an optimal antigen for targeted cancer therapy is challenging as the antigen landscape on cancerous tissues mimics that of healthy tissues, with few unique tumor-specific antigens identified in individual patients. pH low insertion peptides (pHLIPs) act as a unique delivery platform that can specifically target the acidic microenvironment of tumors, sparing healthy tissue in the process. We developed a pHLIP-peptide conjugate to deliver the SIINFEKL peptide, an immunogenic fragment of ovalbumin, to tumor cells in vivo. When processed intracellularly, SIINFEKL is presented for immune recognition through the major histocompatibility complex (MHC) class I pathway. We observed selective delivery of pHLIP-SIINFEKL both in vitro and in vivo using fluorescently labeled constructs. In vitro, treatment of melanoma tumor cells with pHLIP-SIINFEKL resulted in recognition by SIINFEKL-specific T cells (OT1), leading to T cell activation and effector function. Mechanistically, we show that this recognition by OT1 cells was abrogated by siRNA/shRNA knockdown of multiple components within the MHC class I pathway in the target tumor cells, indicating that an intact antigen processing pathway in the cancer cells is necessary to mediate the effect of pHLIP-directed SIINFEKL delivery. In vivo, pHLIP-SIINFEKL treatment of tumor-bearing mice resulted in recruitment of OT1 T cells and suppression of tumor growth in two syngeneic tumor models in immunocompetent mice, with no effect when mutating either the pHLIP or SIINFEKL components of the conjugate. These results suggest that pHLIP-mediated peptide delivery can be used to deliver novel artificial antigens that can be targeted by cell-based therapies.

Frequency of Screening and Spontaneous Breathing Trial Techniques: A Randomized Clinical Trial.

Importance: The optimal screening frequency and spontaneous breathing trial (SBT) technique to liberate adults from ventilators are unknown. Objective: To compare the effects of screening frequency (once-daily screening vs more frequent screening) and SBT technique (pressure-supported SBT with a pressure support level that was >0-≤8 cm H2O and a positive end-expiratory pressure [PEEP] level that was >0-≤5 cm H2O vs T-piece SBT) on the time to successful extubation. Design, Setting, and Participants: Randomized clinical trial with a 2 × 2 factorial design including critically ill adults who were receiving invasive mechanical ventilation for at least 24 hours, who were capable of initiating spontaneous breaths or triggering ventilators, and who were receiving a fractional concentration of inspired oxygen that was 70% or less and a PEEP level of 12 cm H2O or less. Recruitment was between January 2018 and February 2022 at 23 intensive care units in North America; last follow-up occurred October 18, 2022. Interventions: Participants were enrolled early to enable protocolized screening (more frequent vs once daily) to identify the earliest that patients met criteria to undergo pressure-supported or T-piece SBT lasting 30 to 120 minutes. Main Outcome and Measures: Time to successful extubation (time when unsupported, spontaneous breathing began and was sustained for ≥48 hours after extubation). Results: Of 797 patients (198 in the once-daily screening and pressure-supported SBT group, 204 in once-daily screening and T-piece SBT, 195 in more frequent screening and pressure-supported SBT, and 200 in more frequent screening and T-piece SBT), the mean age was 62.4 (SD, 18.4) years and 472 (59.2%) were men. There were no statistically significant differences by screening frequency (hazard ratio [HR], 0.88 [95% CI, 0.76-1.03]; P = .12) or by SBT technique (HR, 1.06 [95% CI, 0.91-1.23]; P = .45). The median time to successful extubation was 2.0 days (95% CI, 1.7-2.7) for once-daily screening and pressure-supported SBT, 3.1 days (95% CI, 2.7-4.8) for once-daily screening and T-piece SBT, 3.9 days (95% CI, 2.9-4.7) for more frequent screening and pressure-supported SBT, and 2.9 days (95% CI, 2.0-3.1) for more frequent screening and T-piece SBT. An unexpected interaction between screening frequency and SBT technique required pairwise contrasts that revealed more frequent screening (vs once-daily screening) and pressure-supported SBT increased the time to successful extubation (HR, 0.70 [95% CI, 0.50-0.96]; P = .02). Once-daily screening and pressure-supported SBT (vs T-piece SBT) did not reduce the time to successful extubation (HR, 1.30 [95% CI, 0.98-1.70]; P = .08). Conclusions and Relevance: Among critically ill adults who received invasive mechanical ventilation for more than 24 hours, screening frequency (once-daily vs more frequent screening) and SBT technique (pressure-supported vs T-piece SBT) did not change the time to successful extubation. However, an unexpected and statistically significant interaction was identified; protocolized more frequent screening combined with pressure-supported SBTs increased the time to first successful extubation. Trial Registration: ClinicalTrials.gov Identifiers: NCT02399267 and NCT02969226.

Joint Models Inform the Longitudinal Assessment of Patient-Reported Outcomes in Clinical Trials: A Simulation Study and Secondary Analysis of the Restrictive versus Liberal Fluid Therapy for Major Abdominal Surgery (RELIEF) Randomized Controlled Trial.

OBJECTIVE: Evaluate the utility of a joint model when analysing a patient-reported endpoint as part of a randomized controlled trial in which censoring occurs when patients die during follow-up. STUDY DESIGN AND SETTING: The present study comprises two parts: first we re-analyzed data from a previously published randomized controlled trial comparing two fluid regimens in the first 24 hours of major abdomino-pelvic surgery ('RELIEF' trial). In this trial, patient-reported disability was measured at multiple timepoints before and after surgery. Next, we conducted a simulation study to jointly emulate patient-reported disability and survival, similar to the RELIEF trial, under nine treatment-outcome scenarios. In both parts, we compared a joint model analysis to a linear mixed effect model combined with one of several traditional methods of handling longitudinal missingness: available data analysis, complete case analysis, last observation carried forward, and worst-case assumption. RESULTS: In part one, the joint model revealed no between-group differences in patient-reported disability at one, three, six, and 12 months after surgery. The worst-case approach consistently resulted in the largest deviation from the joint model estimates, although in this particular setting none of the approaches materially changed the study's conclusions. In part two, the simulations revealed that across all treatment-outcome scenarios, the joint model expectedly produced unbiased estimates of patient-reported disability. Similarly, employing an approach based on all available data (i.e., relying on the maximum likelihood estimator for handling missingness) yielded disability estimates close to the simulated values, albeit with slight bias across some scenarios. The last observation carried forward approach mirrored the joint model's estimates except when the treatment had a non-null effect on patient-reported disability. The worst case analysis resulted in high bias, which was particularly evident when the treatment had a large effect on survival. The complete case analysis resulted in high bias across all scenarios. CONCLUSIONS: In randomized trials that employ a patient-reported outcome as one of their endpoints, a joint model can address bias arising from informative missingness related to death. Methods for handling missingness based on all available data appear to be a reasonable alternative to joint models, with only slight bias across some simulated scenarios.

Atrial Mechanics, Atrial Cardiomyopathy and Impact of Atrial Interventions.

Our comprehension of atrial mechanics, atrial cardiomyopathy and their clinical implications across various cardiovascular conditions has advanced significantly. Atrial interventions can have differing effects on atrial mechanics. With the rapid increase in the use of atrial interventions, it is crucial for investigators and clinicians to acknowledge the potential adverse effects of these interventions on atrial mechanics that might not be clinically significant at the time of interventions. Recognizing the preclinical stage of atrial maladaptation might enable early interventions before the development of irreversible atrial remodeling and clinical manifestation. We review normal atrial function and mechanics, and atrial cardiomyopathy in select cardiovascular conditions. We also summarize and discuss the current evidence of the impact of various atrial interventions on atrial function and mechanics.

A DNA barcoding framework for taxonomic verification in the Darwin Tree of Life Project.

Biodiversity genomics research requires reliable organismal identification, which can be difficult based on morphology alone. DNA-based identification using DNA barcoding can provide confirmation of species identity and resolve taxonomic issues but is rarely used in studies generating reference genomes. Here, we describe the development and implementation of DNA barcoding for the Darwin Tree of Life Project (DToL), which aims to sequence and assemble high quality reference genomes for all eukaryotic species in Britain and Ireland. We present a standardised framework for DNA barcode sequencing and data interpretation that is then adapted for diverse organismal groups. DNA barcoding data from over 12,000 DToL specimens has identified up to 20% of samples requiring additional verification, with 2% of seed plants and 3.5% of animal specimens subsequently having their names changed. We also make recommendations for future developments using new sequencing approaches and streamlined bioinformatic approaches.

Identifying species based solely on their morphology can be difficult. DNA-based identification using DNA barcoding can aid species identification, but can be challenging to implement in biodiversity projects sampling diverse organismal groups. Here, we describe the development and implementation of DNA barcoding for the Darwin Tree of Life Project (DToL), which aims to sequence and assemble high quality reference genomes for all eukaryotic species in Britain and Ireland. We discuss how a standardised approach has been adapted by each partner to suit different organismal groups, show the efficacy of this approach for confirming species identities and resolving taxonomic issues, and make recommendations for future developments.

An evaluation of mirikizumab for the treatment of ulcerative colitis.

INTRODUCTION: Treatment of ulcerative colitis (UC) aims to reduce symptoms and complications by decreasing intestinal inflammation. A proportion of patients do not respond to, do not tolerate, or are inappropriate candidates for current therapies. Interleukin (IL)-23 is a novel therapeutic target and mirikizumab is the first anti-IL-23 antibody approved for the treatment of moderately to severely active UC. AREAS COVERED: This review summarizes the pro-inflammatory effects of IL-23 and outlines the pharmacokinetics of mirikizumab. It provides a synopsis of the available phase II and phaseIII evidence for the efficacy and safety of mirikizumab in UC. EXPERT OPINION: The mirikizumab clinical development program demonstrated its superiority over placebo and its favorable safety profile in the treatment of UC. Its positioning in therapeutic algorithms remains to be fully understood but mirikizumab has proven efficacy in both advanced therapy (AT)-naïve and AT-experienced patients. The inclusion in the license of extended induction for non-responders as well as rescue intravenous dosing allows for flexibility in patient with limited primary response and secondary loss of response.