Exposure to medium and high ambient levels of ozone causes adverse systemic inflammatory and cardiac autonomic effects.

Epidemiological evidence suggests that exposure to ozone increases cardiovascular morbidity. However, the specific biological mechanisms mediating ozone-associated cardiovascular effects are unknown. To determine whether short-term exposure to ambient levels of ozone causes changes in biomarkers of cardiovascular disease including heart rate variability (HRV), systemic inflammation, and coagulability, 26 subjects were exposed to 0, 100, and 200 ppb ozone in random order for 4 h with intermittent exercise. HRV was measured and blood samples were obtained immediately before (0 h), immediately after (4 h), and 20 h after (24 h) each exposure. Bronchoscopy with bronchoalveolar lavage (BAL) was performed 20 h after exposure. Regression modeling was used to examine dose-response trends between the endpoints and ozone exposure. Inhalation of ozone induced dose-dependent adverse changes in the frequency domains of HRV across exposures consistent with increased sympathetic tone [increase of (parameter estimate ± SE) 0.4 ± 0.2 and 0.3 ± 0.1 in low- to high-frequency domain HRV ratio per 100 ppb increase in ozone at 4 h and 24 h, respectively (P = 0.02 and P = 0.01)] and a dose-dependent increase in serum C-reactive protein (CRP) across exposures at 24 h [increase of 0.61 ± 0.24 mg/l in CRP per 100 ppb increase in ozone (P = 0.01)]. Changes in HRV and CRP did not correlate with ozone-induced local lung inflammatory responses (BAL granulocytes, IL-6, or IL-8), but changes in HRV and CRP were associated with each other after adjustment for age and ozone level. Inhalation of ozone causes adverse systemic inflammatory and cardiac autonomic effects that may contribute to the cardiovascular mortality associated with short-term exposure.

Secreted Wingless-interacting molecule (Swim) promotes long-range signaling by maintaining Wingless solubility.

Lipid-modified Wnt/Wingless (Wg) proteins can signal to their target cells in a short- or long-range manner. How these hydrophobic proteins travel through the extracellular environment remains an outstanding question. Here, we report on a Wg binding protein, Secreted Wg-interacting molecule (Swim), that facilitates Wg diffusion through the extracellular matrix. Swim, a putative member of the Lipocalin family of extracellular transport proteins, binds to Wg with nanomolar affinity in a lipid-dependent manner. In quantitative signaling assays, Swim is sufficient to maintain the solubility and activity of purified Wg. In Drosophila, swim RNAi phenotypes resemble wg loss-of-function phenotypes in long-range signaling. We propose that Swim is a cofactor that promotes long-range Wg signaling in vivo by maintaining the solubility of Wg.

A high affinity recombinant antibody to the human EphA3 receptor with enhanced ADCC activity.

EphA3 is expressed in solid tumors and leukemias and is an attractive target for the therapy. We have generated a panel of Humaneered® antibodies to the ligand-binding domain using a Fab epitope-focused library that has the same specificity as monoclonal antibody mIIIA4. A high-affinity antibody was selected that competes with the mIIIA4 antibody for binding to EphA3 and has an improved affinity of ∼1 nM. In order to generate an antibody with potent cell-killing activity the variable regions were assembled with human IgG1k constant regions and expressed in a Chinese hamster ovary (CHO) cell line deficient in fucosyl transferase. Non-fucosylated antibodies have been reported to have enhanced binding affinity for the IgG receptor CD16a (FcγRIIIa). The affinity of the antibody for recombinant CD16a was enhanced approximately 10-fold. This resulted in enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) activity against EphA3-expressing leukemic cells, providing a potent antibody for the evaluation as a therapeutic agent.

Completing records-based research within the military: a user's guide.

Many of the orthopaedic studies completed within the military come from records-based research. This methodological article will assist researchers in completing such studies by highlighting the experiences and lessons learned from a recent retrospective study on amputees. Specifically, this article provides details on the various data sources available within the military, and how to access those systems, and offers general advice for the completion of retrospective studies using Department of Defense data systems. Although there are many obstacles that need to be overcome in order to successfully complete records-based research within the military, the authors hope this article will aid investigators in the completion of future projects.

Burnout among public sector pharmacy staff two years into the COVID-19 pandemic.

OBJECTIVES: This study aimed to determine the prevalence and factors contributing to burnout among public sector pharmacy staff in Sarawak, Malaysia, two years into the COVID-19 pandemic. Impact of burnout on their lives and their coping strategies were also examined. METHODS: A cross-sectional online survey was carried out among all pharmacy staff in public healthcare facilities throughout Sarawak. Burnout was measured using the Copenhagen Burnout Inventory. Multiple logistic regression analysed demographic and work characteristics associated with burnout. Open-ended replies on burnout causes, impact, coping strategies and employer's role were coded and thematically analysed. KEY FINDINGS: A total of 329 responses were received. The prevalence of personal, work and patient-related burnout was 54.7, 47.1 and 35.3%, respectively. Respondents facing problems with child support were 8.26 and 3.62 times more likely to suffer from personal and work-related burnout. Working in areas with potential exposure to COVID-19 patients increased the odds of patient and work-related burnout by 2.80 and 1.86 times, respectively. Burnout symptoms affected their quality of life; nevertheless, self-reported coping strategies were mostly positive. Respondents emphasised the need for organisational interventions, including increased resource allocation, better workload distribution and promotion of work-life balance, to mitigate burnout. CONCLUSIONS: A significant percentage of public sector pharmacy staff continue to experience burnout two years into the pandemic. Regular well-being assessments and supportive policies are recommended to help them cope with increased stress. Additional training for supervisors may be necessary to effectively manage staff and workload during a pandemic.

Actigraphy informs distinct patient-centered outcomes in Pre-COPD.

BACKGROUND: Actigraphy can provide useful patient-centered outcomes for quantification of physical activity in the "real-world" setting. METHODS: To characterize the relationship of actigraphy outputs with "in-laboratory" measures of cardiopulmonary function and respiratory symptoms in pre-COPD, we obtained actigraphy data for 8 h/day for 5 consecutive days a week before in-laboratory administration of respiratory questionnaires, PFT, and CPET to a subgroup of subjects participating in the larger study of the health effects of exposure to secondhand tobacco smoke who had air trapping but no spirometric obstruction (pre-COPD). Using machine learning approaches, we identified the most relevant actigraphy predictors and examined their associations with symptoms, lung function, and exercise outcomes. RESULTS: Sixty-one subjects (age = 66±7 years; BMI = 24±3 kg/m2; FEV1/FVC = 0.75 ± 0.05; FEV1 = 103 ± 17 %predicted) completed the nested study. In the hierarchical cluster analysis, the activity, distance, and energy domains of actigraphy, including moderate to vigorous physical activity, were closely correlated with each other, but were only loosely associated with spirometric and peak exercise measures of oxygen consumption, ventilation, oxygen-pulse, and anaerobic threshold (VO2AT), and were divergent from symptom measures. Conversely, the sedentary domain clustered with respiratory symptoms, air trapping, airflow indices, and ventilatory efficiency. In Regression modeling, sedentary domain was inversely associated with baseline lung volumes and tidal breathing at peak exercise, while the activity domains were associated with VO2AT. Respiratory symptoms and PFT data were not associated with actigraphy outcomes. DISCUSSION: Outpatient actigraphy can provide information for "real-world" patient-centered outcomes that are not captured by standardized respiratory questionnaires, lung function, or exercise testing. Actigraphy activity and sedentary domains inform of distinct outcomes.

Accelerated neuronal differentiation toward motor neuron lineage from human embryonic stem cell line (H9).

Motor neurons loss plays a pivotal role in the pathoetiology of various debilitating diseases such as, but not limited to, amyotrophic lateral sclerosis, primary lateral sclerosis, progressive muscular atrophy, progressive bulbar palsy, pseudobulbar palsy, and spinal muscular atrophy. However, advancement in motor neuron replacement therapy has been significantly constrained by the difficulties in large-scale production at a cost-effective manner. Current methods to derive motor neuron heavily rely on biochemical stimulation, chemical biological screening, and complex physical cues. These existing methods are seriously challenged by extensive time requirements and poor yields. An innovative approach that overcomes prior hurdles and enhances the rate of successful motor neuron transplantation in patients is of critical demand. Iron, a trace element, is indispensable for the normal development and function of the central nervous system. Whether ferric ions promote neuronal differentiation and subsequently promote motor neuron lineage has never been considered. Here, we demonstrate that elevated iron concentration can drastically accelerate the differentiation of human embryonic stem cells (hESCs) toward motor neuron lineage potentially via a transferrin mediated pathway. HB9 expression in 500 nM iron-treated hESCs is approximately twofold higher than the control. Moreover, iron treatment generated more matured and functional motor neuron-like cells that are ∼1.5 times more sensitive to depolarization when compared to the control. Our methodology renders an expedited approach to harvest motor neuron-like cells for disease, traumatic injury regeneration, and drug screening.

Lipid-independent secretion of a Drosophila Wnt protein.

Wnt proteins comprise a large class of secreted signaling molecules with key roles during embryonic development and throughout adult life. Recently, much effort has been focused on understanding the factors that regulate Wnt signal production. For example, Porcupine and Wntless/Evi/Sprinter have been identified as being required in Wnt-producing cells for the processing and secretion of many Wnt proteins. Interestingly, in this study we find that WntD, a recently characterized Drosophila Wnt family member, does not require Porcupine or Wntless/Evi/Sprinter for its secretion or signaling activity. Because Porcupine is involved in post-translational lipid modification of Wnt proteins, we used a novel labeling method and mass spectrometry to ask whether WntD undergoes lipid modification and found that it does not. Although lipid modification is also hypothesized to be required for Wnt secretion, we find that WntD is secreted very efficiently. WntD secretion does, however, maintain a requirement for the secretory pathway component Rab1. Our results show that not all Wnt family members require lipid modification, Porcupine, or Wntless/Evi/Sprinter for secretion and suggest that different modes of secretion may exist for different Wnt proteins.

A dedicated Wnt secretion factor.

The Wnt family of signaling proteins mediates cell-cell communication during development. In this issue of Cell, Bänziger et al. (2006) and Bartscherer et al. (2006) identify Wntless/Evi, a multipass transmembrane protein in the secretory pathway of Wnt-producing cells that promotes Wnt secretion.

Axonal metabolic recovery and potential neuroprotective effect of glatiramer acetate in relapsing-remitting multiple sclerosis.

Glatiramer acetate (GA) is a disease-modifying therapy for relapsing-remitting multiple sclerosis (RRMS) with several putative mechanisms of action. Currently, there is paucity of in vivo human data linking the well-established peripheral immunologic effects of therapy with GA to its potential effects inside the central nervous system (CNS). Brain proton magnetic resonance spectroscopy (MRS) allows in vivo examination of axonal integrity by quantifying the resonance intensity of the neuronal marker N-acetylaspartate (NAA). In a pilot study to investigate the effect of GA on axonal injury, we performed combined brain magnetic resonance imaging (MRI) and MRS studies in 18 treatment naïve RRMS patients initiating therapy with GA at baseline and annually for two years on therapy. A small group of four treatment naïve RRMS patients, electing to remain untreated, served as controls. NAA/Cr was measured in a large central brain volume of interest (VOI) as well as the normal appearing white matter (NAWM) within the VOI. After two years, NAA/Cr in the GA-treated group increased significantly by 10.7% in the VOI (2.17 +/- 0.26 versus 1.96 +/- 0.24, P = 0.03) and by 71% in the NAWM (2.23 +/- 0.26 versus 2.08 +/- 0.31, P = 0.04). In the untreated group, NAA/Cr decreased by 8.9% at two years in the VOI (2.01 +/- 0.16 versus 1.83 +/- 0.21, P = 0.03) and 8.2% in the NAWM (2.07 +/- 0.24 versus 1.90 +/- 0.29, P = 0.03). Our data shows that treatment with GA leads to axonal metabolic recovery and protection from sub-lethal axonal injury. These results support an in situ effect of GA therapy inside the CNS and suggest potential neuroprotective effects of GA.

Disruption of segmental neural crest migration and ephrin expression in delta-1 null mice.

Neural crest cells migrate segmentally through the rostral half of each trunk somite due to inhibitory influences of ephrins and other molecules present in the caudal-half of somites. To examine the potential role of Notch/Delta signaling in establishing the segmental distribution of ephrins, we examined neural crest migration and ephrin expression in Delta-1 mutant mice. Using Sox-10 as a marker, we noted that neural crest cells moved through both rostral and caudal halves of the somites in mutants, consistent with the finding that ephrinB2 levels are significantly reduced in the caudal-half somites. Later, mutant embryos had aberrantly fused and/or reduced dorsal root and sympathetic ganglia, with a marked diminution in peripheral glia. These results show that Delta-1 is essential for proper migration and differentiation of neural crest cells. Interestingly, absence of Delta-1 leads to diminution of both neurons and glia in peripheral ganglia, suggesting a general depletion of the ganglion precursor pool in mutant mice.