Genome streamlining in Parcubacteria transitioning from soil to groundwater.

BACKGROUND: To better understand the influence of habitat on the genetic content of bacteria, with a focus on members of Candidate Phyla Radiation (CPR) bacteria, we studied the effects of transitioning from soil via seepage waters to groundwater on genomic composition of ultra-small Parcubacteria, the dominating CPR class in seepage waters, using genome resolved metagenomics. RESULTS: Bacterial metagenome-assembled genomes (MAGs), (318 total, 32 of Parcubacteria) were generated from seepage waters and compared directly to groundwater counterparts. The estimated average genome sizes of members of major phyla Proteobacteria, Bacteroidota and Cand. Patescibacteria (Candidate Phyla Radiation - CPR bacteria) were significantly higher in soil-seepage water as compared to their groundwater counterparts. Seepage water Parcubacteria (Paceibacteria) exhibited 1.18-fold greater mean genome size and 2-fold lower mean proportion of pseudogenes than those in groundwater. Bacteroidota and Proteobacteria also showed a similar trend of reduced genomes in groundwater compared to seepage. While exploring gene loss and adaptive gains in closely related CPR lineages in groundwater, we identified a membrane protein, and a lipoglycopeptide resistance gene unique to a seepage Parcubacterium genome. A nitrite reductase gene was also identified and was unique to the groundwater Parcubacteria genomes, likely acquired from other planktonic microbes via horizontal gene transfer. CONCLUSIONS: Overall, our data suggest that bacteria in seepage waters, including ultra-small Parcubacteria, have significantly larger genomes and higher metabolic enrichment than their groundwater counterparts, highlighting possible genome streamlining of the latter in response to habitat selection in an oligotrophic environment.

Can a Liquid Biopsy Detect Circulating Tumor DNA With Low-passage Whole-genome Sequencing in Patients With a Sarcoma? A Pilot Evaluation.

BACKGROUND: A liquid biopsy is a test that evaluates the status of a disease by analyzing a sample of bodily fluid, most commonly blood. In recent years, there has been progress in the development and clinical application of liquid biopsy methods to identify blood-based, tumor-specific biomarkers for many cancer types. However, the implementation of these technologies to aid in the treatment of patients who have a sarcoma remains behind other fields of cancer medicine. For this study, we chose to evaluate a sarcoma liquid biopsy based on circulating tumor DNA (ctDNA). All human beings have normal cell-free DNA (cfDNA) circulating in the blood. In contrast with cfDNA, ctDNA is genetic material present in the blood stream that is derived from a tumor. ctDNA carries the unique genomic fingerprint of the tumor with changes that are not present in normal circulating cfDNA. A successful ctDNA liquid biopsy must be able to target these tumor-specific genetic alterations. For instance, epidermal growth factor receptor (EGFR) mutations are common in lung cancers, and ctDNA liquid biopsies are currently in clinical use to evaluate the status of disease in patients who have a lung cancer by detecting EGFR mutations in the blood. As opposed to many carcinomas, sarcomas do not have common recurrent mutations that could serve as the foundation to a ctDNA liquid biopsy. However, many sarcomas have structural changes to their chromosomes, including gains and losses of portions or entire chromosomes, known as copy number alterations (CNAs), that could serve as a target for a ctDNA liquid biopsy. Murine double minute 2 (MDM2) amplification in select lipomatous tumors or parosteal osteosarcoma is an example of a CNA due to the presence of extra copies of a segment of the long arm of chromosome 12. Since a majority of sarcomas demonstrate a complex karyotype with numerous CNAs, a blood-based liquid biopsy strategy that searches for these CNAs may be able to detect the presence of sarcoma ctDNA. Whole-genome sequencing (WGS) is a next-generation sequencing technique that evaluates the entire genome. The depth of coverage of WGS refers to how detailed the sequencing is, like higher versus lower power on a microscope. WGS can be performed with high-depth sequencing (that is, > 60×), which can detect individual point mutations, or low-depth sequencing (that is, 0.1× to 5×), referred to as low-passage whole-genome sequencing (LP-WGS), which may not detect individual mutations but can detect structural chromosomal changes including gains and losses (that is, CNAs). While similar strategies have shown favorable early results for specific sarcoma subtypes, LP-WGS has not been evaluated for applicability to the broader population of patients who have a sarcoma. QUESTIONS/PURPOSES: Does an LP-WGS liquid biopsy evaluating for CNAs detect ctDNA in plasma samples from patients who have sarcomas representing a variety of histologic subtypes? METHODS: This was a retrospective study conducted at a community-based, tertiary referral center. Nine paired (plasma and formalin-fixed paraffin-embedded [FFPE] tissue) and four unpaired (plasma) specimens from patients who had a sarcoma were obtained from a commercial biospecimen bank. Three control specimens from individuals who did not have cancer were also obtained. The paired and unpaired specimens from patients who had a sarcoma represented a variety of sarcoma histologic subtypes. cfDNA was extracted, amplified, and quantified. Libraries were prepared, and LP-WGS was performed using a NextSeq 500 next-generation sequencing machine at a low depth of sequencing coverage (∼1×). The ichorCNA bioinformatics algorithm, which was designed to detect CNAs from low-depth genomic sequencing data, was used to analyze the data. In contrast with the gold standard for diagnosis in the form of histopathologic analysis of a tissue sample, this test does not discriminate between sarcoma subtypes but detects the presence of tumor-derived CNAs within the ctDNA in the blood that should not be present in a patient who does not have cancer. The liquid biopsy was positive for the detection of cancer if the ichorCNA algorithm detected the presence of ctDNA. The algorithm was also used to quantitatively estimate the percent ctDNA within the cfDNA. The concentration of ctDNA was then calculated from the percent ctDNA relative to the total concentration of cfDNA. The CNAs of the paired FFPE tissue and plasma samples were graphically visualized using aCNViewer software. RESULTS: This LP-WGS liquid biopsy detected ctDNA in 9 of 13 of the plasma specimens from patients with a sarcoma. The other four samples from patients with a sarcoma and all serum specimens from patients without cancer had no detectable ctDNA. Of those 9 patients with positive liquid biopsy results, the percent ctDNA ranged from 6% to 11%, and calculated ctDNA quantities were 0.04 to 5.6 ng/mL, which are levels to be expected when ctDNA is detectable. CONCLUSION: In this small pilot study, we were able to detect sarcoma ctDNA with an LP-WGS liquid biopsy searching for CNAs in the plasma of most patients who had a sarcoma representing a variety of histologic subtypes. CLINICAL RELEVANCE: These results suggest that an LP-WGS liquid biopsy evaluating for CNAs to identify ctDNA may be more broadly applicable to the population of patients who have a sarcoma than previously reported in studies focusing on specific subtypes. Large prospective clinical trials that gather samples at multiple time points during the process of diagnosis, treatment, and surveillance will be needed to further assess whether this technique can be clinically useful. At our institution, we are in the process of developing a large prospective clinical trial for this purpose.

Corticosterone release in very young siblicidal seabird chicks (Rissa tridactyla) is sensitive to environmental variability and responds rapidly and robustly to external challenges.

In birds, patterns of development of the adrenocortical response to stressors vary among individuals, types of stressors, and species. Since there are benefits and costs of exposure to elevated glucocorticoids, this variation is presumably a product of selection such that animals modulate glucocorticoid secretion in contexts where doing so increases their fitness. In this study, we evaluated hypothalamo-pituitary-adrenal (HPA) activity in first-hatched free-living seabird nestlings that engage in intense sibling competition and facultative siblicide (black-legged kittiwakes, Rissa tridactyla). We sampled 5 day old chicks (of the ∼45 day nestling period), a critical early age when food availability drives establishment of important parent-offspring and intra-brood dynamics. We experimentally supplemented parents with food ("supplemented") and measured chick baseline corticosterone secretion and capacity to rapidly increase corticosterone in response to an acute challenge (handling and 15 min of restraint in a bag). We also used topical administration of corticosterone to evaluate the ability of chicks to downregulate physiologically relevant corticosterone levels on a short time scale (minutes). We found that 5 day old chicks are not hypo-responsive but release corticosterone in proportion to the magnitude of the challenge, showing differences in baseline between parental feeding treatments (supplemented vs non-supplemented), moderate increases in response to handling, and a larger response to restraint (comparable to adults) that also differed between chicks from supplemented and control nests. Topical application of exogenous corticosterone increased circulating levels nearly to restraint-induced levels and induced downregulation of HPA responsiveness to the acute challenge of handling. Parental supplemental feeding did not affect absorbance/clearance or negative feedback. Thus, while endogenous secretion of corticosterone in young chicks is sensitive to environmental context, other aspects of the HPA function, such as rapid negative feedback and/or the ability to clear acute elevations in corticosterone, are not. We conclude that 5 day old kittiwake chicks are capable of robust adrenocortical responses to novel challenges, and are sensitive to parental food availability, which may be transduced behaviorally, nutritionally, or via maternal effects. Questions remain about the function of such rapid, large acute stress-induced increases in corticosterone in very young chicks.

Genetic basis of clarithromycin resistance in Bacillus anthracis.

The high-consequence pathogen Bacillus anthracis causes human anthrax and often results in lethal infections without the rapid administration of effective antimicrobial treatment. Antimicrobial resistance profiling is therefore critical to inform post-exposure prophylaxis and treatment decisions, especially during emergencies such as outbreaks or where intentional release is suspected. Whole-genome sequencing using a rapid long-read sequencer can uncover antimicrobial resistance patterns if genetic markers of resistance are known. To identify genomic markers associated with antimicrobial resistance, we isolated B. anthracis derived from the avirulent Sterne strain with elevated minimal inhibitory concentrations to clarithromycin. Mutants were characterized both phenotypically through broth microdilution susceptibility testing and observations during culturing, as well as genotypically with whole-genome sequencing. We identified two different in-frame insertions in the L22 ribosomal protein-encoding gene rplV, which were subsequently confirmed to be involved in clarithromycin resistance through the reversion of the mutant gene to the parent (drug-susceptible) sequence. Detection of the rplV insertions was possible with rapid long-read sequencing, with a time-to-answer within 3 h. The mutations associated with clarithromycin resistance described here will be used in conjunction with known genetic markers of resistance for other antimicrobials to strengthen the prediction of antimicrobial resistance in B. anthracis.IMPORTANCEThe disease anthrax, caused by the pathogen Bacillus anthracis, is extremely deadly if not treated quickly and appropriately. Clarithromycin is an antibiotic recommended for the treatment and post-exposure prophylaxis of anthrax by the Centers for Disease Control and Prevention; however, little is known about the ability of B. anthracis to develop resistance to clarithromycin or the mechanism of that resistance. The characterization of clarithromycin-resistant isolates presented here provides valuable information for researchers and clinicians in the event of a release of the resistant strain. Additionally, knowledge of the genetic basis of resistance provides a foundation for susceptibility prediction through rapid genome sequencing to inform timely treatment decisions.

Dietary restriction of isoleucine increases healthspan and lifespan of genetically heterogeneous mice.

Low-protein diets promote health and longevity in diverse species. Restriction of the branched-chain amino acids (BCAAs) leucine, isoleucine, and valine recapitulates many of these benefits in young C57BL/6J mice. Restriction of dietary isoleucine (IleR) is sufficient to promote metabolic health and is required for many benefits of a low-protein diet in C57BL/6J males. Here, we test the hypothesis that IleR will promote healthy aging in genetically heterogeneous adult UM-HET3 mice. We find that IleR improves metabolic health in young and old HET3 mice, promoting leanness and glycemic control in both sexes, and reprograms hepatic metabolism in a sex-specific manner. IleR reduces frailty and extends the lifespan of male and female mice, but to a greater degree in males. Our results demonstrate that IleR increases healthspan and longevity in genetically diverse mice and suggests that IleR, or pharmaceuticals that mimic this effect, may have potential as a geroprotective intervention.

Structural and biochemical characterisation of the N-carbamoyl-ß-alanine amidohydrolase from Rhizobium radiobacter MDC 8606.

N-carbamoyl-ß-alanine amidohydrolase (CßAA) constitutes one of the most important groups of industrially relevant enzymes used in the production of optically pure amino acids and derivatives. In this study, a CßAA-encoding gene from Rhizobium radiobacter strain MDC 8606 was cloned and overexpressed in Escherichia coli. The purified recombinant enzyme (RrCßAA) showed a specific activity of 14 U·mg-1 using N-carbamoyl-ß-alanine as a substrate with an optimum activity at 55 °C and pH 8.0. In this work, we report also the first prokaryotic CßAA structure at a resolution of 2.0 Å. A discontinuous catalytic domain and a dimerisation domain attached through a flexible hinge region at the domain interface have been revealed. We identify key ligand binding residues, including a conserved glutamic acid (Glu131), histidine (H385) and arginine (Arg291). Our results allowed us to explain the preference of the enzyme for linear carbamoyl substrates, as large and branched carbamoyl substrates cannot fit in the active site of the enzyme. This work envisages the use of RrCßAA from R. radiobacter MDC 8606 for the industrial production of L-α-, L-ß- and L-γ-amino acids. The structural analysis provides new insights on enzyme-substrate interaction, which shed light on engineering of CßAAs for high catalytic activity and broad substrate specificity.

The straight-wire appliance: Individualization versus customization.

The straight-wire appliance is an individualized, fully-programmed appliance system that has been in clinical use since the early 1970s. A study of tooth positions in individuals with naturally occurring harmonious occlusions led to the discovery of the Six Keys to Normal (Optimal) Occlusion which provided data for bracket features and prescription values incorporated into the straight-wire appliance. It was based on the notion that tooth anatomy, morphology, and optimal positions were alike enough among individuals, regardless of age, sex, or race to justify using prefabricated brackets with average prescription values. New technologies have led to advancements in appliance customization. Customized brackets can be made-to-order with one-of-a-kind prescription values and bracket base contours that fit precisely to the morphologic characteristics of the teeth. If costs and material qualities were comparable, would treatment efficiency or treatment outcomes be superior when using a customized appliance compared with a prefabricated straight-wire appliance? If not, why not?

Differential contribution of nitrifying prokaryotes to groundwater nitrification.

The ecophysiology of complete ammonia-oxidizing bacteria (CMX) of the genus Nitrospira and their widespread occurrence in groundwater suggests that CMX bacteria have a competitive advantage over ammonia-oxidizing bacteria (AOB) and archaea (AOA) in these environments. However, the specific contribution of their activity to nitrification processes has remained unclear. We aimed to disentangle the contribution of CMX, AOA and AOB to nitrification and to identify the environmental drivers of their niche differentiation at different levels of ammonium and oxygen in oligotrophic carbonate rock aquifers. CMX ammonia monooxygenase sub-unit A (amoA) genes accounted on average for 16 to 75% of the total groundwater amoA genes detected. Nitrification rates were positively correlated to CMX clade A associated phylotypes and AOB affiliated with Nitrosomonas ureae. Short-term incubations amended with the nitrification inhibitors allylthiourea and chlorate suggested that AOB contributed a large fraction to overall ammonia oxidation, while metaproteomics analysis confirmed an active role of CMX in both ammonia and nitrite oxidation. Ecophysiological niche differentiation of CMX clades A and B, AOB and AOA was linked to their requirements for ammonium, oxygen tolerance, and metabolic versatility. Our results demonstrate that despite numerical predominance of CMX, the first step of nitrification in oligotrophic groundwater appears to be primarily governed by AOB. Higher growth yields at lower ammonia turnover rates and energy derived from nitrite oxidation most likely enable CMX to maintain consistently high populations.

Changing Agendas on Sleep, Treatment and Learning in Epilepsy (CASTLE) Sleep-E: a protocol for a randomised controlled trial comparing an online behavioural sleep intervention with standard care in children with Rolandic epilepsy.

INTRODUCTION: Sleep and epilepsy have an established bidirectional relationship yet only one randomised controlled clinical trial has assessed the effectiveness of behavioural sleep interventions for children with epilepsy. The intervention was successful, but was delivered via face-to-face educational sessions with parents, which are costly and non-scalable to population level. The Changing Agendas on Sleep, Treatment and Learning in Epilepsy (CASTLE) Sleep-E trial addresses this problem by comparing clinical and cost-effectiveness in children with Rolandic epilepsy between standard care (SC) and SC augmented with a novel, tailored parent-led CASTLE Online Sleep Intervention (COSI) that incorporates evidence-based behavioural components. METHODS AND ANALYSES: CASTLE Sleep-E is a UK-based, multicentre, open-label, active concurrent control, randomised, parallel-group, pragmatic superiority trial. A total of 110 children with Rolandic epilepsy will be recruited in outpatient clinics and allocated 1:1 to SC or SC augmented with COSI (SC+COSI). Primary clinical outcome is parent-reported sleep problem score (Children's Sleep Habits Questionnaire). Primary health economic outcome is the incremental cost-effectiveness ratio (National Health Service and Personal Social Services perspective, Child Health Utility 9D Instrument). Parents and children (≥7 years) can opt into qualitative interviews and activities to share their experiences and perceptions of trial participation and managing sleep with Rolandic epilepsy. ETHICS AND DISSEMINATION: The CASTLE Sleep-E protocol was approved by the Health Research Authority East Midlands (HRA)-Nottingham 1 Research Ethics Committee (reference: 21/EM/0205). Trial results will be disseminated to scientific audiences, families, professional groups, managers, commissioners and policymakers. Pseudo-anonymised individual patient data will be made available after dissemination on reasonable request. TRIAL REGISTRATION NUMBER: ISRCTN13202325.

Genomic alterations and clinical outcomes in patients with dedifferentiated liposarcoma.

PURPOSE: Patients with unresectable dedifferentiated liposarcoma (DDLPS) have poor overall outcomes. Few genomic alterations have been identified with limited therapeutic options. EXPERIMENTAL DESIGN: Patients treated at Levine Cancer Institute with DDLPS were identified. Next generation sequencing (NGS), immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH) testing were performed on tumor tissue collected at diagnosis or recurrence/progression. Confirmation of genomic alterations was performed by orthologous methods and correlated with clinical outcomes. Univariate Cox regression was used to identify genomic alterations associated with clinical outcomes. RESULTS: Thirty-eight DDLPS patients with adequate tissue for genomic profiling and clinical data were identified. Patient characteristics included: median age at diagnosis (66 years), race (84.2% Caucasian), and median follow-up time for the entire cohort was 12.1 years with a range from approximately 3.5 months to 14.1 years. Genes involved in cell cycle regulation, including MDM2 (74%) CDK4 (65%), and CDKN2A (23%), were amplified along with WNT/Notch pathway markers: HMGA2, LGR5, MCL1, and CALR (19%-29%). While common gene mutations were identified, PDE4DIP and FOXO3 were also mutated in 47% and 34% of patients, respectively, neither of which have been previously reported. FOXO3 was associated with improved overall survival (OS) (HR 0.37; p = 0.043) along with MAML2 (HR 0.30; p = 0.040). Mutations that portended worse prognosis included RECQL4 (disease-specific survival HR 4.67; p = 0.007), MN1 (OS HR = 3.38; p = 0.013), NOTCH1 (OS HR 2.28, p = 0.086), and CNTRL (OS HR 2.42; p = 0.090). CONCLUSIONS: This is one of the largest retrospective reports analyzing genomic aberrations in relation to clinical outcomes for patients with DDLPS. Our results suggest therapies targeting abnormalities should be explored and confirmation of prognostic markers is needed. Dedifferentiated liposarcoma is one of the most common subtypes of soft tissue sarcoma yet little is known of its molecular aberrations and possible impact on outcomes. The work presented here is an evaluation of genetic abnormalities among a population of patients with dedifferentiated liposarcoma and how they corresponded with survival and risk of metastases. There were notable gene mutations and amplifications commonly found, some of which had interesting prognostic implications.

Applications of 3D Photography in Craniofacial Surgery.

Three-dimensional (3D) photography is becoming more common in craniosynostosis practice and may be used for research, archiving, and as a planning tool. In this article, an overview of the uses of 3D photography will be given, including systems available and illustrations of how they can be used. Important innovations in 3D computer vision will also be discussed, including the potential role of statistical shape modeling and analysis as an outcomes tool with presentation of some results and a review of the literature on the topic. Potential future applications in diagnostics using machine learning will also be presented.

Come Roll with Me: An Interprofessional Experience to Promote Disability Awareness.

Problem: One in four American adults have a disability, which makes people with disabilities the largest minority group in the United States (U.S.). Chronic diseases are prevalent within this population, which faces myriad barriers that limit access to healthcare and create significant health care disparities. Yet, disability awareness programs are limited in U.S. medical schools and graduates report a sense of unpreparedness to care for this population. Intervention: Come Roll with Me (CRWM) was implemented as an interprofessional, preclinical experience to provide medical and Doctor of Physical Therapy (DPT) students an opportunity to engage with wheelchair users and one another. Students rotated through four stations with a licensed physical therapist and wheelchair user facilitator. Stations included (1) manual wheelchair self-propulsion, (2) accessible parking, (3) transfers, and (4) open dialog on barriers to healthcare led by the wheelchair user. Context: This study sought to assess the impact of CRWM on students' understanding of the barriers and health disparities faced by individuals with disabilities. Assessment was conducted using course evaluations, thematic analysis of student reflection essays and a focus group with the wheelchair user facilitators to determine if CRWM met pre-implementation program goals and objectives, including the Interprofessional Educational Collaborative (IPEC) core competencies. Impact: Student reflections from both disciplines indicated that learners were able to identify a variety of barriers faced by people with disabilities and prioritize methods to mitigate these factors. Approximately 91% of medical students agreed or strongly agreed that CRWM was effective in their learning on course evaluations. Wheelchair user facilitators noted three important outcomes of CRWM: educating, teaming, and impact on students. Lesson Learned: Come Roll with Me is a robust educational activity, as evidenced by the program meeting all goals and objectives as well as (IPEC) core competencies. It provides students a unique opportunity to learn about disability from another profession and wheelchair users. People with disabilities and DPT students are a unique and underutilized pool of educators in undergraduate medical education.

A novel and robust method for counting components within bio-molecular complexes using fluorescence microscopy and statistical modelling.

Cellular biology occurs through myriad interactions between diverse molecular components, many of which assemble in to specific complexes. Various techniques can provide a qualitative survey of which components are found in a given complex. However, quantitative analysis of the absolute number of molecules within a complex (known as stoichiometry) remains challenging. Here we provide a novel method that combines fluorescence microscopy and statistical modelling to derive accurate molecular counts. We have devised a system in which batches of a given biomolecule are differentially labelled with spectrally distinct fluorescent dyes (label A or B), and mixed such that B-labelled molecules are vastly outnumbered by those with label A. Complexes, containing this component, are then simply scored as either being positive or negative for label B. The frequency of positive complexes is directly related to the stoichiometry of interaction and molecular counts can be inferred by statistical modelling. We demonstrate this method using complexes of Adenovirus particles and monoclonal antibodies, achieving counts that are in excellent agreement with previous estimates. Beyond virology, this approach is readily transferable to other experimental systems and, therefore, provides a powerful tool for quantitative molecular biology.

Redefining the phylogenetic and metabolic diversity of phylum Omnitrophota.

The candidate phylum Omnitrophica-recently termed Omnitrophota, and originally known as OP3-is an understudied bacterial clade that has primarily been found in aquatic ecosystems. To characterize the diversity and ecology of this phylum, we reconstructed 55 Omnitrophota metagenome-assembled genomes (MAGs) from a well-characterized groundwater system within central Germany and placed them within the context of publicly available genomes. Seven clades were identified, four of which contained novel genomes obtained from our groundwater system. All clades exhibited the capacity for type IV pili, type II secretion systems, glycogen storage, and carbohydrate degradation. Only the characterized Cand. Omnitrophus magneticus genome exhibited functions associated with magnetosome construction. Clades were characterized by sets of traits rather than unique pathways, which were then used to infer ecological strategies. These lifestyles consisted of mixotrophs, obligate fermenters, and versatile respiratory heterotrophs. Patterns in 16S rRNA gene amplicons from a 6 years, monthly sampled groundwater time-series dataset reflected the persistent and widespread occurrence of Clade 7 Wood-Ljungdahl utilizing mixotrophs and highlight this group as a core member of the groundwater community. Overall, this study uncovered, characterized, and contextualized the metabolic and phylogenetic diversity within phylum Omnitrophota, and predicts that environmental populations may mediate both nitrogen and sulfur cycling, along with organic matter production and degradation within aquatic ecosystems.

Telomere length correlates with physiological and behavioural responses of a long-lived seabird to an ecologically relevant challenge.

Determinants of individual variation in reallocation of limited resources towards self-maintenance versus reproduction are not well known. We tested the hypothesis that individual heterogeneity in long-term 'somatic state' (i) explains variation in endocrine and behavioural responses to environmental challenges, and (ii) is associated with variation in strategies for allocating to self-maintenance versus reproduction. We used relative telomere length as an indicator of somatic state and experimentally generated an abrupt short-term reduction of food availability (withdrawal of food supplementation) for free-living seabirds (black-legged kittiwakes, Rissa tridactyla). Incubating male kittiwakes responded to withdrawal by increasing circulating corticosterone and losing more weight compared to continuously supplemented controls. Males with longer telomeres increased time in directed travel regardless of treatment, while experiencing smaller increases in corticosterone. Males with longer telomeres fledged more chicks in the control group and tended to be more likely to return regardless of treatment. This study supports the hypothesis that somatic state can explain variation in short-term physiological and behavioural responses to challenges, and longer-term consequences for fitness. Male kittiwakes with longer telomeres appear to have prioritized investment in self over investment in offspring under challenging conditions.

Dual-axis thrust stand for the direct characterization of electrospray performance.

A dual-axis torsional thrust stand was successfully demonstrated at the Air Force Research Laboratory, enabling direct simultaneous thrust and mass loss measurement for the Air Force Electrospray Thruster Series 2 passively fed electrospray thruster. The dual-axis system is effectively two nulled torsional thrust stands sharing a single dual-axis gimbal with a thrust and mass resolution of ±0.2 µN and ±0.04 mg, respectively. The development of this system was inspired by a need for direct efficiency characterization of electrosprays via in situ mass measurements, and performance was compared to thruster masses measured pre- and post-testing using an analytical balance. Mass consumption data captured via the dual-axis stand, which is calibrated to a traceable uncertainty of 1.6%, varied between -5% and 18% as compared to analytical balance measurements throughout a multi-month testing effort highlighting the limitations in pre/post-weighing as a method for capturing propellant consumption due to absorption of atmospheric moisture when thrusters are removed from vacuum. Thrust stand tests were limited to short term operation with a daily available testing window of ∼5 h due to thrust stand drift following the 24 h cyclic temperature variations of the testing facility. A thorough investigation into the root cause of ambient thermal drift suggests that the thermal response of commercial flex-pivot bearings is directly producing spurious torques on the order of 10 µN m/°C. Additionally, unresolved charging effects on thrust stand hardware currently limit thrust stand operation to tests operating with a positive thruster polarity. Further development and long duration test stability require both a targeted investigation into flex-pivot thermal response and minimization of facility effects.

Kinematic Analysis of Lateral Meniscal Oblique Radial Tears in Anterior Cruciate Ligament-Reconstructed Knees: Untreated Versus Repair Versus Partial Meniscectomy.

BACKGROUND: Lateral meniscal oblique radial tears (LMORTs) affect joint and meniscal stability in anterior cruciate ligament (ACL)-deficient knees. PURPOSE: To determine the clinically relevant kinematics associated with the most common posterior horn LMORT lesion types, types 3 (LMORT3) and 4 (LMORT4), untreated versus arthroscopic repair versus partial meniscectomy in combination with ACL reconstruction (ACLR). STUDY: Controlled laboratory study. METHODS: Sixteen cadaveric knees underwent robotic testing for anterior drawer and pivot-shift simulations at multiple knee flexion angles in ACL-intact and ACL-deficient states, followed by sequential testing of arthroscopic ACLR, LMORT3 lesion, LMORT3 repair, and partial meniscectomy (n = 8). The same testing sequence was performed for LMORT4 lesions (n = 8). RESULTS: ACLR restored kinematics in ACL-deficient knees to intact levels for all metrics tested. For anterior drawer, ACLR + LMORT3 tear and partial meniscectomy resulted in significantly greater anterior translation compared with ACL-intact at all angles (P < .05) and compared with ACLR at 60° and 90° (P < .014). For pivot shift, compared with ACL-intact knees, ACLR + LMORT3 tear resulted in significantly more anterior translation at 15° (P = .041); and for ACLR + partial meniscectomy, at both 0° and 15° (P < .03). ACLR + LMORT4 tear and partial meniscectomy resulted in significantly greater anterior translation for anterior drawer (P < .04) and pivot-shift testing (P < .05) compared with intact and ACLR knees at all angles tested. ACLR + LMORT3 repair and ACLR + LMORT4 repair restored kinematics to ACLR and intact levels at all angles tested. ACLR + LMORT3 tear (P < .008) and both LMORT4 tear and partial meniscectomy (P < .05) resulted in increased meniscal extrusion compared with intact and ACLR statuses at all tested angles for anterior drawer and pivot shift, while repairs restored meniscal stability to ACLR and intact levels. CONCLUSION: Untreated LMORT tears increased anterior translation, pivot shift, and meniscal extrusion after ACLR, while partial meniscectomy further exacerbated these detrimental effects in this cadaveric model. In contrast, arthroscopic side-to-side repair of LMORT lesions effectively restored measured knee kinematics. CLINICAL RELEVANCE: LMORT lesions are common with ACL tears and adversely affect joint stability and meniscal extrusion. This study highlights the importance of repair of LMORT 3 and 4 lesions at the time of ACLR.

Synchronization in renal microcirculation unveiled with high-resolution blood flow imaging.

Internephron interaction is fundamental for kidney function. Earlier studies have shown that nephrons signal to each other, synchronize over short distances, and potentially form large synchronized clusters. Such clusters would play an important role in renal autoregulation, but due to the technological limitations, their presence is yet to be confirmed. In the present study, we introduce an approach for high-resolution laser speckle imaging of renal blood flow and apply it to estimate the frequency and phase differences in rat kidney microcirculation under different conditions. The analysis unveiled the spatial and temporal evolution of synchronized blood flow clusters of various sizes, including the formation of large (>90 vessels) and long-lived clusters (>10 periods) locked at the frequency of the tubular glomerular feedback mechanism. Administration of vasoactive agents caused significant changes in the synchronization patterns and, thus, in nephrons' co-operative dynamics. Specifically, infusion of vasoconstrictor angiotensin II promoted stronger synchronization, while acetylcholine caused complete desynchronization. The results confirm the presence of the local synchronization in the renal microcirculatory blood flow and that it changes depending on the condition of the vascular network and the blood pressure, which will have further implications for the role of such synchronization in pathologies development.

Methods for Extrapolating Survival Analyses for the Economic Evaluation of Advanced Therapy Medicinal Products.

There are two significant challenges for analysts conducting economic evaluations of advanced therapy medicinal products (ATMPs): (1) estimating long-term treatment effects in the absence of mature clinical data and (2) capturing potentially complex hazard functions. This review identifies and critiques a variety of methods that can be used to overcome these challenges. The narrative review is informed by a rapid literature review of methods used for the extrapolation of survival analyses in the economic evaluation of ATMPs. There are several methods that are more suitable than traditional parametric survival modeling approaches for capturing complex hazard functions, including, cure-mixture models and restricted cubic spline models. In the absence of mature clinical data, analysts may augment clinical trial data with data from other sources to aid extrapolation, however, the relative merits of applying methods for including data from different sources is not well understood. Given the high and potentially irrecoverable costs of making incorrect decisions concerning the reimbursement or commissioning of ATMPs, it is important that economic evaluations are correctly specified, and that both parameter and structural uncertainty associated with survival extrapolations are considered. Value of information analyses allow for this uncertainty to be expressed explicitly, and in monetary terms.

Advances in Manufacturing Cardiomyocytes from Human Pluripotent Stem Cells.

The emergence of human pluripotent stem cell (hPSC) technology over the past two decades has provided a source of normal and diseased human cells for a wide variety of in vitro and in vivo applications. Notably, hPSC-derived cardiomyocytes (hPSC-CMs) are widely used to model human heart development and disease and are in clinical trials for treating heart disease. The success of hPSC-CMs in these applications requires robust, scalable approaches to manufacture large numbers of safe and potent cells. Although significant advances have been made over the past decade in improving the purity and yield of hPSC-CMs and scaling the differentiation process from 2D to 3D, efforts to induce maturation phenotypes during manufacturing have been slow. Process monitoring and closed-loop manufacturing strategies are just being developed. We discuss recent advances in hPSC-CM manufacturing, including differentiation process development and scaling and downstream processes as well as separation and stabilization.