Dysregulated STAT3 signaling and T cell immunometabolic dysfunction define a targetable, high mortality subphenotype of critically ill children.

Sepsis is the leading cause of death of hospitalized children worldwide. Despite the established link between immune dysregulation and mortality in pediatric sepsis, it remains unclear which host immune factors contribute causally to adverse sepsis outcomes. Identifying modifiable pathobiology is an essential first step to successful translation of biologic insights into precision therapeutics. We designed a prospective, longitudinal cohort study of 88 critically ill pediatric patients with multiple organ dysfunction syndrome (MODS), including patients with and without sepsis, to define subphenotypes associated with targetable mechanisms of immune dysregulation. We first assessed plasma proteomic profiles and identified shared features of immune dysregulation in MODS patients with and without sepsis. We then employed consensus clustering to define three subphenotypes based on protein expression at disease onset and identified a strong association between subphenotype and clinical outcome. We next identified differences in immune cell frequency and activation state by MODS subphenotype and determined the association between hyperinflammatory pathway activation and cellular immunophenotype. Using single cell transcriptomics, we demonstrated STAT3 hyperactivation in lymphocytes from the sickest MODS subgroup and then identified an association between STAT3 hyperactivation and T cell immunometabolic dysregulation. Finally, we compared proteomics findings between patients with MODS and patients with inborn errors of immunity that amplify cytokine signaling pathways to further assess the impact of STAT3 hyperactivation in the most severe patients with MODS. Overall, these results identify a potentially pathologic and targetable role for STAT3 hyperactivation in a subset of pediatric patients with MODS who have high severity of illness and poor prognosis.

Reproducible protocol for the extraction and semi-automated quantification of macroscopic charcoal from soil.

Charcoal fragments preserved in soils or sediments are used by scientists to reconstruct fire histories and thereby improve our understanding of past vegetation dynamics and human-plant relationships. Unfortunately, most published methods for charcoal extraction and analysis are incompletely described and are therefore difficult to reproduce. To improve the standardization and replicability of soil charcoal analysis, as well as to facilitate accessibility for non-experts, we developed a detailed, step-by-step protocol to isolate charcoal from soil and to efficiently count and measure charcoal fragments. The extraction phase involves the chemical soaking and wet sieving of soils followed by the collection of macrocharcoal (≥500 µm). The analysis phase is performed semi-automatically using the open-source software ImageJ to count and measure the area, length, and width of fragments from light stereo microscope images by means of threshold segmentation. The protocol yields clean charcoal fragments, a set of charcoal images, and datasets containing total charcoal mass, number of fragments, and morphological measurements (area, length, and width) for each sample. We tested and validated the protocol on 339 soil samples from tropical savannas and forests in eastern lowland Bolivia. We hope that this protocol will be a valuable resource for scientists in a variety of fields who currently study, or wish to study, macroscopic charcoal in soils as a proxy for past fires.

Identifying longitudinal cognitive resilience from cross-sectional amyloid, tau, and neurodegeneration.

BACKGROUND: Leveraging Alzheimer's disease (AD) imaging biomarkers and longitudinal cognitive data may allow us to establish evidence of cognitive resilience (CR) to AD pathology in-vivo. Here, we applied latent class mixture modeling, adjusting for sex, baseline age, and neuroimaging biomarkers of amyloid, tau and neurodegeneration, to a sample of cognitively unimpaired older adults to identify longitudinal trajectories of CR. METHODS: We identified 200 Harvard Aging Brain Study (HABS) participants (mean age = 71.89 years, SD = 9.41 years, 59% women) who were cognitively unimpaired at baseline with 2 or more timepoints of cognitive assessment following a single amyloid-PET, tau-PET and structural MRI. We examined latent class mixture models with longitudinal cognition as the dependent variable and time from baseline, baseline age, sex, neocortical Aß, entorhinal tau, and adjusted hippocampal volume as independent variables. We then examined group differences in CR-related factors across the identified subgroups from a favored model. Finally, we applied our favored model to a dataset from the Alzheimer's Disease Neuroimaging Initiative (ADNI; n = 160, mean age = 73.9 years, SD = 7.6 years, 60% women). RESULTS: The favored model identified 3 latent subgroups, which we labelled as Normal (71% of HABS sample), Resilient (22.5%) and Declining (6.5%) subgroups. The Resilient subgroup exhibited higher baseline cognitive performance and a stable cognitive slope. They were differentiated from other groups by higher levels of verbal intelligence and past cognitive activity. In ADNI, this model identified a larger Normal subgroup (88.1%), a smaller Resilient subgroup (6.3%) and a Declining group (5.6%) with a lower cognitive baseline. CONCLUSION: These findings demonstrate the value of data-driven approaches to identify longitudinal CR groups in preclinical AD. With such an approach, we identified a CR subgroup who reflected expected characteristics based on previous literature, higher levels of verbal intelligence and past cognitive activity.

Cell type-specific regulation by different cytokinetic pathways in the early embryo.

Cytokinesis, the physical division of one cell into two, is typically assumed to use the same molecular process across animal cells. However, regulation of cell division can vary significantly among different cell types, even within the same multicellular organism. Using six fast-acting temperature-sensitive (ts) cytokinesis-defective mutants, we found that each had unique cell type-specific profiles in the early C. elegans embryo. Certain cell types were more sensitive than others to actomyosin and spindle signaling disruptions, disrupting two members of the same complex could result in different phenotypes, and protection against actomyosin inhibition did not always protect against spindle signaling inhibition.

Colony context and size-dependent compensation mechanisms give rise to variations in nuclear growth trajectories.

To investigate the fundamental question of how cellular variations arise across spatiotemporal scales in a population of identical healthy cells, we focused on nuclear growth in hiPS cell colonies as a model system. We generated a 3D timelapse dataset of thousands of nuclei over multiple days, and developed open-source tools for image and data analysis and an interactive timelapse viewer for exploring quantitative features of nuclear size and shape. We performed a data-driven analysis of nuclear growth variations across timescales. We found that individual nuclear volume growth trajectories arise from short timescale variations attributable to their spatiotemporal context within the colony. We identified a strikingly time-invariant volume compensation relationship between nuclear growth duration and starting volume across the population. Notably, we discovered that inheritance plays a crucial role in determining these two key nuclear growth features while other growth features are determined by their spatiotemporal context and are not inherited.

Leveraging Habits to Improve Adherence to Gout Medications: A Qualitative Study.

OBJECTIVE: This study investigates patients' medication-taking routines and the feasibility of harnessing habit formation through context cues and rewards to improve medication adherence. METHODS: Semistructured qualitative interviews with patients with gout from an urban health care system were conducted to explore typical medication-taking behavior, experiences using electronic pill bottles, barriers to adherence, existing context cues, and potential cues and rewards for habit-forming behavior. Medication-taking patterns were recorded for six weeks using electronic pill bottles before interviews to inform discussion. Transcribed interviews were analyzed to generate themes using codes developed by the study team, with representative quotations selected as illustrations. RESULTS: We conducted interviews with 15 individuals (mean age 60.6 [SD 20.3] years, three women [20%], and nine White patients [60%]). Pill bottle-recorded adherence to urate-lowering therapy (ULT) was high (mean 0.91 [SD 0.10]), and one patient was experiencing an active gout flare. Five key themes emerged: (1) reasons for nonadherence, (2) internal and external motivations for adherence, (3) structured routines around taking medications, (4) rewards for good medication adherence, and (5) the role of pill cap technology in medication-taking. CONCLUSION: The importance of a predictable, structured routine in which participants could incorporate their medication-taking behavior emerged as a key factor that promoted consistent adherence. Further, identifying context cues and reminders seemed to promote incorporation of medication-taking into routines. Therefore, habit-based interventions that use context cues to establish routines around medication-taking may be a feasible strategy to improve adherence in patients with chronic conditions such as gout.

Cervical spine proprioception and vestibular/oculomotor function: An observational study comparing young adults with and without a concussion history.

OBJECTIVE: To investigate dizziness, vestibular/oculomotor symptoms, and cervical spine proprioception among adults with/without a concussion history. METHODS: Adults ages 18-40 years with/without a concussion history completed: dizziness handicap inventory (DHI), visio-vestibular exam (VVE), and head repositioning accuracy (HRA, assesses cervical spine proprioception). Linear regression models were used to assess relationships between (1) concussion/no concussion history group and VVE, HRA, and DHI, and (2) DHI with HRA and VVE for the concussion history group. RESULTS: We enrolled 42 participants with concussion history (age = 26.5 ± 4.5 years, 79% female, mean = 1.4± 0.8 years post-concussion) and 46 without (age = 27.0± 3.8 years, 74% female). Concussion history was associated with worse HRA (ß = 1.23, 95% confidence interval [CI]: 0.77, 1.68; p < 0.001), more positive VVE subtests (ß = 3.01, 95%CI: 2.32, 3.70; p < 0.001), and higher DHI scores (ß = 9.79, 95%CI: 6.27, 13.32; p < 0.001) after covariate adjustment. For the concussion history group, number of positive VVE subtests was significantly associated with DHI score (ß = 3.78, 95%CI: 2.30, 5.26; p < 0.001) after covariate adjustment, while HRA error was not (ß = 1.10, 95%CI: -2.32, 4.51; p = 0.52). CONCLUSIONS: Vestibular/oculomotor symptom provocation and cervical spine proprioception impairments may persist chronically (i.e., 3 years) after concussion. Assessing dizziness, vestibular/oculomotor and cervical spine function after concussion may inform patient-specific treatments to address ongoing dysfunction.

Bone marrow-derived myeloid cells transiently colonize the brain during postnatal development and interact with glutamatergic synapses.

Although the roles of embryonic yolk sac-derived, resident microglia in neurodevelopment were extensively studied, the possible involvement of bone marrow-derived cells remains elusive. In this work, we used a fate-mapping strategy to selectively label bone marrow-derived cells and their progeny in the brain (FLT3+IBA1+). FLT3+IBA1+ cells were confirmed to be transiently present in the healthy brain during early postnatal development. FLT3+IBA1+ cells have a distinct morphology index at postnatal day(P)0, P7, and P14 compared with neighboring microglia. FLT3+IBA1+ cells also express the microglial markers P2RY12 and TMEM119 and interact with VGLUT1 synapses at P14. Scanning electron microscopy indeed showed that FLT3+ cells contact and engulf pre-synaptic elements. Our findings suggest FLT3+IBA1+ cells might assist microglia in their physiological functions in the developing brain including synaptic pruning which is performed using their purinergic sensors. Our findings stimulate further investigation on the involvement of peripheral macrophages during homeostatic and pathological development.

The Diagnostic Utility of Cervical Spine Proprioception for Adolescent Concussion.

OBJECTIVE: Cervical spine proprioception may be impaired after concussion. Our objective was to determine the diagnostic utility of cervical spine proprioception for adolescent concussion. DESIGN: Cross-sectional. SETTING: Research laboratory. PARTICIPANTS: Adolescents ≤18 days of concussion and uninjured controls. INTERVENTIONS: N/A. MAIN OUTCOMES: Head repositioning accuracy (HRA) testing, a measure of cervical spine proprioception. The HRA test involved patients relocating their head back to a neutral starting position with eyes closed after maximal cervical spine flexion, extension, and right and left rotations. The overall HRA error score was the mean error (distance from the starting point to self-reported return to neutral) across 12 trials: 3 trials in each direction. We used t-tests to compare group means and logistic regression (outcome = group, predictor = HRA, covariates) to calculate odds ratios. We used a receiver operator characteristic curve to evaluate area under the curve (AUC) and calculate the optimal HRA cutpoint to distinguish concussion from controls. RESULTS: We enrolled and tested 46 participants with concussion (age = 15.8 ± 1.3 years, 59% female, mean = 11.3 ± 3.3 days postconcussion) and 83 uninjured controls (age = 16.1 ± 1.4 years, 88% female). The concussion group had significantly worse HRA than controls (4.3 ± 1.6 vs 2.9 ± 0.7 degrees, P < 0.001, Cohen d = 1.19). The univariable HRA model AUC was 0.81 (95% CI = 0.73, 0.90). After adjusting for age, sex, and concussion history, the multivariable model AUC improved to 0.85 (95% CI = 0.77, 0.92). The model correctly classified 80% of participants as concussion/control at a 3.5-degree cutpoint. CONCLUSIONS: Adolescents with concussion demonstrated worse cervical spine proprioception than uninjured controls. Head repositioning accuracy may offer diagnostic utility for subacute concussion.

Spatial extent as a sensitive amyloid-PET metric in preclinical Alzheimer's disease.

INTRODUCTION: Spatial extent-based measures of how far amyloid beta (Aß) has spread throughout the neocortex may be more sensitive than traditional Aß-positron emission tomography (PET) measures of Aß level for detecting early Aß deposits in preclinical Alzheimer's disease (AD) and improve understanding of Aß's association with tau proliferation and cognitive decline. METHODS: Pittsburgh Compound-B (PIB)-PET scans from 261 cognitively unimpaired older adults from the Harvard Aging Brain Study were used to measure Aß level (LVL; neocortical PIB DVR) and spatial extent (EXT), calculated as the proportion of the neocortex that is PIB+. RESULTS: EXT enabled earlier detection of Aß deposits longitudinally confirmed to reach a traditional LVL-based threshold for Aß+ within 5 years. EXT improved prediction of cognitive decline (Preclinical Alzheimer Cognitive Composite) and tau proliferation (flortaucipir-PET) over LVL. DISCUSSION: These findings indicate EXT may be more sensitive to Aß's role in preclinical AD than level and improve targeting of individuals for AD prevention trials. HIGHLIGHTS: Aß spatial extent (EXT) was measured as the percentage of the neocortex with elevated Pittsburgh Compound-B. Aß EXT improved detection of Aß below traditional PET thresholds. Early regional Aß deposits were spatially heterogeneous. Cognition and tau were more closely tied to Aß EXT than Aß level. Neocortical tau onset aligned with reaching widespread neocortical Aß.

Biocompatibility of mussel-inspired water-soluble tissue adhesives.

Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion-based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet-adhesion strength, and long-term bonding. Catechol chemistry has shown great promise in developing wet-set adhesives that meet these criteria. Herein, we have studied the biocompatibility of a catechol-based copolymer adhesive, poly([dopamine methacrylamide]-co-[methyl methacrylate]-co-[poly(ethylene glycol) methyl ether methacrylate]) or poly(catechol-MMA-OEG), which is soluble in water. The adhesive was injected subcutaneously in a mouse model on its own and in combination with a sodium periodate crosslinker. After 72 h, 4 weeks, and 12 weeks, the mice were euthanized and subjected to histopathological analysis. Both adhesives were present and still palpable at the end of 12 weeks. The moderate inflammation observed for the poly(catechol-MMA-OEG) cohort at 72 h had reduced to mild inflammation at the end of 12 weeks. However, the moderate inflammatory response observed for the poly(catechol-MMA-OEG) + crosslinker cohort at 72 h had not subsided at 12 weeks.

The effect of underlying diseases on pneumonia risk in patients with neurogenic or tumor-related dysphagia: a retrospective cohort study.

OBJECTIVE: To analyze the association of neurological disorders (ND) and head and neck cancer (HNC) with dysphagia severity and aspiration pneumonia occurrence. METHOD: Retrospective cohort study conducted at a university dysphagia center) for two consecutive years. Patients with ND or HNC were included if they had undergone a flexible endoscopic swallowing evaluation (FEES) at the dysphagia center, and at least one food consistency had been sampled and recorded. Outcomes of interest were swallowing safety, highest penetration-aspiration-score (PASmax), way of food intake, presence of a tracheal tube, and occurrence of pneumonia within the past two years. RESULTS: Of 257 consecutive patients, 199 were enrolled in the study and classified according to their underlying diagnosis into ND (120 patients) or HNC (79 patients). Forty-three HNC patients (54.4%) and 54 ND patients (45%) showed critical dysphagia in FEES (PAS ≥ 6). Binary logistic regression comparing both groups showed patients with ND to be 2.31 times more likely to develop pneumonia. However, if the 32 stroke patients were excluded from the calculation, PASmax remains the only significant variable affecting pneumonia risk in both groups. Liquids were the main challenge for ND patients, while aspirating HNC patients struggled with all consistencies. CONCLUSIONS: The study shows that patients with HNC and ND differ in pneumonia risk only if stroke patients are included in the ND group. If they are excluded, the PAS score is the only remaining risk factor for pneumonia. Thickening liquids may not be suitable for all dysphagic patients; individually tailored measures might be more helpful, especially for HNC patients.

Maternal inheritance of functional centrioles in two parthenogenetic nematodes.

Centrioles are the core constituent of centrosomes, microtubule-organizing centers involved in directing mitotic spindle assembly and chromosome segregation in animal cells. In sexually reproducing species, centrioles degenerate during oogenesis and female meiosis is usually acentrosomal. Centrioles are retained during male meiosis and, in most species, are reintroduced with the sperm during fertilization, restoring centriole numbers in embryos. In contrast, the presence, origin, and function of centrioles in parthenogenetic species is unknown. We found that centrioles are maternally inherited in two species of asexual parthenogenetic nematodes and identified two different strategies for maternal inheritance evolved in the two species. In Rhabditophanes diutinus, centrioles organize the poles of the meiotic spindle and are inherited by both the polar body and embryo. In Disploscapter pachys, the two pairs of centrioles remain close together and are inherited by the embryo only. Our results suggest that maternally-inherited centrioles organize the embryonic spindle poles and act as a symmetry-breaking cue to induce embryo polarization. Thus, in these parthenogenetic nematodes, centrioles are maternally-inherited and functionally replace their sperm-inherited counterparts in sexually reproducing species.

Identification and transcriptomic assessment of latent profile pediatric septic shock phenotypes.

BACKGROUND: Sepsis poses a grave threat, especially among children, but treatments are limited owing to heterogeneity among patients. We sought to test the clinical and biological relevance of pediatric septic shock subclasses identified using reproducible approaches. METHODS: We performed latent profile analyses using clinical, laboratory, and biomarker data from a prospective multi-center pediatric septic shock observational cohort to derive phenotypes and trained a support vector machine model to assign phenotypes in an internal validation set. We established the clinical relevance of phenotypes and tested for their interaction with common sepsis treatments on patient outcomes. We conducted transcriptomic analyses to delineate phenotype-specific biology and inferred underlying cell subpopulations. Finally, we compared whether latent profile phenotypes overlapped with established gene-expression endotypes and compared survival among patients based on an integrated subclassification scheme. RESULTS: Among 1071 pediatric septic shock patients requiring vasoactive support on day 1 included, we identified two phenotypes which we designated as Phenotype 1 (19.5%) and Phenotype 2 (80.5%). Membership in Phenotype 1 was associated with ~ fourfold adjusted odds of complicated course relative to Phenotype 2. Patients belonging to Phenotype 1 were characterized by relatively higher Angiopoietin-2/Tie-2 ratio, Angiopoietin-2, soluble thrombomodulin (sTM), interleukin 8 (IL-8), and intercellular adhesion molecule 1 (ICAM-1) and lower Tie-2 and Angiopoietin-1 concentrations compared to Phenotype 2. We did not identify significant interactions between phenotypes, common treatments, and clinical outcomes. Transcriptomic analysis revealed overexpression of genes implicated in the innate immune response and driven primarily by developing neutrophils among patients designated as Phenotype 1. There was no statistically significant overlap between established gene-expression endotypes, reflective of the host adaptive response, and the newly derived phenotypes, reflective of the host innate response including microvascular endothelial dysfunction. However, an integrated subclassification scheme demonstrated varying survival probabilities when comparing patient endophenotypes. CONCLUSIONS: Our research underscores the reproducibility of latent profile analyses to identify pediatric septic shock phenotypes with high prognostic relevance. Pending validation, an integrated subclassification scheme, reflective of the different facets of the host response, holds promise to inform targeted intervention among those critically ill.

Presentation and Outcome in S1P-RM and Natalizumab-Associated Progressive Multifocal Leukoencephalopathy: A Multicenter Cohort Study.

BACKGROUND AND OBJECTIVES: Progressive multifocal leukoencephalopathy (PML) is a severe neurologic disease resulting from JC virus reactivation in immunocompromised patients. Certain multiple sclerosis (MS) disease-modifying therapies (DMTs) are associated with PML risk, such as natalizumab and, more rarely, sphingosine-1-phosphate receptor modulators (S1P-RMs). Although natalizumab-associated PML is well documented, information on S1P-RM-associated PML is limited. The aim of this study is to compare clinical presentations and outcomes between the 2 groups. METHODS: A retrospective multicenter cohort study included patients with PML from 2009 to 2022 treated with S1P-RMs or natalizumab. Data on clinical and radiologic presentation, outcomes, immune reconstitution inflammatory syndrome (IRIS), survival, disability (using the modified Ranking scale-mRS), and MS relapses post-PML were analyzed. RESULTS: Of 88 patients, 84 were analyzed (20 S1P-RM, 64 natalizumab). S1P-RM-associated PML was diagnosed in older patients (median age 52 vs 44 years, p < 0.001) and after longer treatment duration (median 63.9 vs 40 months, p < 0.001). Similarly, S1P-RM patients were more prone to show symptoms at diagnosis (100 vs 80.6%, p = 0.035), had more disseminated lesions (80% vs 34.9%, p = 0.002), and had higher gadolinium enhancement (65% vs 39.1%, p = 0.042). Natalizumab patients had a higher IRIS development rate (OR: 8.3 [1.92-33.3]). Overall, the outcome (mRS) at 12 months was similar in the 2 groups (OR: 0.81 [0.32-2.0]). Yet, post-treatment MS activity was higher in S1P-RM cases (OR: 5.7 [1.4-22.2]). DISCUSSION: S1P-RM-associated PML shows reduced IRIS risk but higher post-treatment MS activity. Clinicians should tailor post-PML treatment based on pre-PML medication.

(R)-(-)-Ketamine: The Promise of a Novel Treatment for Psychiatric and Neurological Disorders.

NMDA receptor antagonists have potential for therapeutics in neurological and psychiatric diseases, including neurodegenerative diseases, epilepsy, traumatic brain injury, substance abuse disorder (SUD), and major depressive disorder (MDD). (S)-ketamine was the first of a novel class of antidepressants, rapid-acting antidepressants, to be approved for medical use. The stereoisomer, (R)-ketamine (arketamine), is currently under development for treatment-resistant depression (TRD). The compound has demonstrated efficacy in multiple animal models. Two clinical studies disclosed efficacy in TRD and bipolar depression. A study by the drug sponsor recently failed to reach a priori clinical endpoints but post hoc analysis revealed efficacy. The clinical value of (R)-ketamine is supported by experimental data in humans and rodents, showing that it is less sedating, does not produce marked psychotomimetic or dissociative effects, has less abuse potential than (S)-ketamine, and produces efficacy in animal models of a range of neurological and psychiatric disorders. The mechanisms of action of the antidepressant effects of (R)-ketamine are hypothesized to be due to NMDA receptor antagonism and/or non-NMDA receptor mechanisms. We suggest that further clinical experimentation with (R)-ketamine will create novel and improved medicines for some of the neurological and psychiatric disorders that are underserved by current medications.

Infant Care: Predictors of Outdoor Walking, Infant Carrying and Infant Outdoor Sleeping.

BACKGROUND: Although spending time outdoors is beneficial for development, little is known about outdoor time during infancy. The aim of this study was to assess frequencies and durations of (1a) outdoor walking and carrying in mother-infant dyads and (1b) infant outdoor sleeping in a stationary cot or pram. We furthermore aimed to identify associations of (2a) outdoor walking and carrying and (2b) infant outdoor sleeping, with infant, maternal and environmental sample characteristics. METHODS: An online survey was distributed among mothers of 0- to 12-month-old infants. Initially, 1453 mothers were recruited, of which 1275 were included in the analyses. With respect to (1a) the outcomes of interest were: mother-infant dyads' total weekly duration of walking in minutes, frequency of walking on weekdays, as well as weekends, and the frequency of using an infant carrier during walks, as well as the daily duration of carrying in hours (indoors and outdoors together). With respect to (1b) the outcome variables were: placing the infant outdoors to sleep (yes/no), the total weekly duration of outdoor sleeping and the weekly frequency of outdoor sleeping. For aim 2, associations of the outcome variables with infant (i.e., age), maternal (i.e., working status) and environmental (i.e., house type) sample characteristics were assessed. RESULTS: Mother-infant dyads engaged in walks for a total weekly duration of 201 min, for approximately one to three walks over weekdays (Monday through Friday), as well as one to three walks on the weekend. The infant carrier was used by 22% of mothers at least half of the time during outdoor walks, and 18% reported a daily duration of infant carrying of one hour or more. Among other associations, infant and maternal enjoyment of outdoor walking correlated positively with the duration as well as the frequency of walking during weekdays and during the weekend. Furthermore, employed mothers walked for a shorter duration and less frequently on weekdays as compared to mothers on maternity leave or mothers without a paid job. The availability of nearby recreational areas correlated positively with the weekly duration and frequency of walks. The infant carrier was used more frequently during outdoor walks if more than one child lived in the household. Infant carrying during outdoor walks was also related to infant behavior at night. Roughly a third of the mothers (29%) regularly had their infant sleep outdoors for a weekly duration of four hours and a weekly frequency of approximately one to two times. Younger infants, infants of mothers with higher education and infants living in detached houses were more likely to be placed outdoors to sleep. DISCUSSION: We identified associations of infant, maternal and environmental characteristics with outdoor time spent during infancy. These results lay the foundation for future research on the effects of the outdoors on child development as well as on facilitators and barriers for caregivers.

Ascorbic acid export from human donor lenses: Is the lens a source of ascorbic acid in the ocular humors?

In previous work, we have shown that the lens acts a reservoir of the antioxidant glutathione (GSH), capable of exporting this antioxidant into the ocular humors and potentially protecting the tissues of the eye that interface with these humors from oxidative stress. In this study, we have extended this work by examining whether the lens acts as a source of ascorbic acid (AsA) to maintain the high levels of AsA known to be present in the ocular humors either by the direct export of AsA into the humors and/or by functioning as a recycling site for AsA, via the direct uptake of oxidised ascorbate (DHA) from the humors, its regeneration to AsA in the lens and then its subsequent export back into the humors. To test this, human lenses of varying ages were cultured for 1 h under hypoxic conditions and AsA/DHA levels measured in the media and in the lens. Human lenses were also cultured in compartmentalised chambers to determine whether efflux of AsA/DHA occurs at the anterior or posterior surface. Immunohistochemistry was performed on human donor lenses and sections labelled with antibodies against GLUT1, a putative DHA uptake transporter. Vitreous humor was collected from patients undergoing vitrectomy who either had a natural clear lens, an artificial intraocular implant (IOL) or a cataractous lens, and AsA/DHA and GSH and oxidised GSH (GSSG) measured. We found that cultured human donor lenses released both AsA and DHA into the media. Culturing of lenses in a compartmentalised chamber revealed that AsA and DHA efflux occurs at both surfaces, with relatively equal amounts of AsA and DHA released from each surface. The posterior surface of the lens was shown to express the GLUT1 transporter. Analysis of vitreous samples from patients undergoing vitrectomy revealed that vitreous GSH and AsA levels were similar between the natural lens group, IOL and cataractous lens group. Taken together, while human donor lenses were shown to export AsA and DHA into the surrounding media, the amount of AsA and DHA released from donor lenses was low and not sufficient to sustain the high levels of total AsA normally present in the humors. This suggests that although the lens is not the main source for maintaining high levels of AsA in the ocular humors, the lens may help to support local AsA levels close to the lens.

Correlation Analysis of Genetic Mutations and Galectin Levels in Breast Cancer Patients.

Galectins are innate immune system regulators associated with disease progression in cancer. This paper aims to investigate the correlation between mutated cancer-critical genes and galectin levels in breast cancer patients to determine whether galectins and genetic profiles can be used as biomarkers for disease and potential therapy targets. Prisma Health Cancer Institute's Biorepository provided seventy-one breast cancer samples, including all four stages spanning the major molecular subtypes and histologies. Hotspot mutation statuses of cancer-critical genes were determined using multiplex PCR in tumor samples from the same patients by Precision Genetics and the University of South Carolina Functional Genomics Core Facility. The galectin-1, -3, and -9 levels in patients' sera were analyzed using Enzyme-linked Immunosorbent Assay (ELISA). An analysis was performed using JMP software to compare mean and median serum galectin levels between samples with and without specific cancer-critical genes, including pooled t-test, Wilcoxon Rank Sum Test, ANOVA, and Steel Dwass Test (α=0.05). Our analysis indicates that KIT mutations correlate with elevated serum levels of galectin-9 in patients with breast cancer. In patients with Luminal A subtype, FLT3 mutation correlates with lower serum galectin-1 and -9 levels and TP53 mutations correlate with higher serum galectin-3 levels. Patients with invasive ductal carcinoma had significantly higher serum galectin-3 levels than patients with ductal carcinoma in situ. Patients with both TP53 and PIK3CA mutations exhibit elevated serum galectin-3 levels, while patients with one or neither mutation show no significant difference in serum galectin-3 levels. In addition, metastatic breast cancer samples were more likely to have a KIT or PIK3CA mutation compared to primary breast cancer samples. The relationship between genetic mutations and galectin levels has the potential to identify appropriate candidates for combined therapy, targeting genetic mutations and galectins. Further understanding of the effect of genetic mutations and galectin levels on cancer progression and metastasis could aid in the search for biomarkers for breast cancer diagnosis, disease progression, and prognosis.