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BACKGROUND: Although many molecules have been investigated as biomarkers for spinal cord injury (SCI) or ischemic stroke, none of them are specifically induced in central nervous system (CNS) neurons following injuries with low baseline expression. However, neuronal injury constitutes a major pathology associated with SCI or stroke and strongly correlates with neurological outcomes. Biomarkers characterized by low baseline expression and specific induction in neurons post-injury are likely to better correlate with injury severity and recovery, demonstrating higher sensitivity and specificity for CNS injuries compared to non-neuronal markers or pan-neuronal markers with constitutive expressions. METHODS: In animal studies, young adult wildtype and global Atf3 knockout mice underwent unilateral cervical 5 (C5) SCI or permanent distal middle cerebral artery occlusion (pMCAO). Gene expression was assessed using RNA-sequencing and qRT-PCR, while protein expression was detected through immunostaining. Serum ATF3 levels in animal models and clinical human samples were measured using commercially available enzyme-linked immune-sorbent assay (ELISA) kits. RESULTS: Activating transcription factor 3 (ATF3), a molecular marker for injured dorsal root ganglion sensory neurons in the peripheral nervous system, was not expressed in spinal cord or cortex of naïve mice but was induced specifically in neurons of the spinal cord or cortex within 1 day after SCI or ischemic stroke, respectively. Additionally, ATF3 protein levels in mouse blood significantly increased 1 day after SCI or ischemic stroke. Importantly, ATF3 protein levels in human serum were elevated in clinical patients within 24 hours after SCI or ischemic stroke. Moreover, Atf3 knockout mice, compared to the wildtype mice, exhibited worse neurological outcomes and larger damage regions after SCI or ischemic stroke, indicating that ATF3 has a neuroprotective function. CONCLUSIONS: ATF3 is an easily measurable, neuron-specific biomarker for clinical SCI and ischemic stroke, with neuroprotective properties. HIGHLIGHTS: ATF3 was induced specifically in neurons of the spinal cord or cortex within 1 day after SCI or ischemic stroke, respectively. Serum ATF3 protein levels are elevated in clinical patients within 24 hours after SCI or ischemic stroke. ATF3 exhibits neuroprotective properties, as evidenced by the worse neurological outcomes and larger damage regions observed in Atf3 knockout mice compared to wildtype mice following SCI or ischemic stroke.

VEGF-A is a key cytokine in tumor angiogenesis and a major therapeutic target for cancer. VEGF165 is the predominant isoform of VEGF-A, and it is the most potent angiogenesis stimulant. VEGFR2/KDR domains 2 and 3 (D2D3) bind to the N-terminal domain (NTD, residues 1-110) of VEGF165. Since removal of the heparin-binding domain (HBD, residues 111-165) markedly reduced the mitogenic activity of the growth factor, it has been proposed that the HBD plays a critical role in the mitogenicity of VEGF165. Here, we report that αvβ3 specifically bound to the isolated VEGF165 HBD but not to VEGF165 NTD. Based on docking simulation and mutagenesis, we identified several critical amino acid residues within the VEGF165 HBD required for αvβ3 binding, i.e., Arg123, Arg124, Lys125, Lys140, Arg145, and Arg149. We discovered that VEGF165 HBD binds to the KDR domain 1 (D1) and identified that Arg123 and Arg124 are critical for KDR D1 binding by mutagenesis, indicating that the KDR D1-binding and αvβ3-binding sites overlap in the HBD. Full-length VEGF165 mutant (R123A/R124A/K125A/K140A/R145A/R149A) defective in αvβ3 and KDR D1 binding failed to induce ERK1/2 phosphorylation, integrin β3 phosphorylation, and KDR phosphorylation and did not support proliferation of endothelial cells, although the mutation did not affect the KDR D2D3 interaction with VEGF165. Since β3-knockout mice are known to show enhanced VEGF165 signaling, we propose that the binding of KDR D1 to the VEGF165 HBD and KDR D2D3 binding to the VEGF165 NTD are critically involved in the potent mitogenicity of VEGF165. We propose that binding competition between KDR and αvβ3 to the VEGF165 HBD endows integrin αvβ3 with regulatory properties to act as a negative regulator of VEGF165 signaling.

Inorganic nanocrystals such as quantum dots (QDs) and upconverting nanoparticles (UCNPs) are uniquely suited for quantitative live-cell imaging and are typically functionalized with ligands to study specific receptors or cellular targets. Antibodies (Ab) are among the most useful targeting reagents owing to their high affinities and specificities, but common nanocrystal labeling methods may orient Ab incorrectly, be reversible or denaturing, or lead to Ab-NP complexes too large for some applications. Here, we show that SpyCatcher proteins, which bind and spontaneously form covalent isopeptide bonds with cognate SpyTag peptides, can conjugate engineered Ab to nanoparticle surfaces with control over stability, orientation, and stoichiometry. Compact SpyCatcher-functionalized QDs and UCNPs may be labeled with short-chain variable fragment Ab (scFv) engineered to bind urokinase-type plasminogen activator receptors (uPAR) that are overexpressed in many human cancers. Confocal imaging of anti-uPAR scFv-QD conjugates shows the antibody mediates specific binding and internalization by breast cancer cells expressing uPAR. Time-lapse imaging of photostable scFv-UCNP conjugates shows that Ab binding causes uPAR internalization with a ∼20 min half-life on the cell surface, and uPAR is internalized to endolysosomal compartments distinct from general membrane stains and without significant recycling to the cell surface. The controlled and stable conjugation of engineered Ab to NPs enables targeting of diverse receptors for live-cell study of their distribution, trafficking, and physiology.

Background: There is little consensus regarding the indications and utility of urinary tract imaging and type of imaging to perform in patients presenting with acute pyelonephritis (APN). Aims: The aims of this systematic review were to, among patients with APN, (i) identify the proportion of patients investigated with ultrasound (US), (ii) identify the proportion of abnormal US and (iii) identify the proportion of patients with a change in management resulting from abnormal US. Methods: A comprehensive search covered two electronic databases (Medline and EMBASE), with selection of studies performed independently by two investigators. Inclusion criteria were English language APN diagnosis and quantification of patients assessed with US or abnormal US results. Quality appraisal used the Newcastle–Ottawa instrument. Results: There were 35 studies included. The proportion of patients assessed with US was reported in 16 manuscripts and ranged from 20% to 94%, with significant heterogeneity and publication bias. The proportion of abnormal US was reported in 31 manuscripts and ranged from 7% to 79%. The proportion of abnormal US leading to change in management was reported in five studies and ranged from 7% to 59%. There was marked heterogeneity among studies included in all three subgroups. Conclusions: Patients with APN are commonly investigated with US, but only a small proportion have abnormalities and appear to be associated with changes in clinical management. The use of routine US for APN is therefore questioned. The identification of clinical variables for appropriate selection of patients to investigate with US requires further research. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Gastric sleeve stenosis (GSS) is an increasingly common adverse event following sleeve gastrectomy for which objective diagnostic criteria are lacking. Impedance planimetry measurements show promise in characterizing GSS, though normal and abnormal benchmark values have never been established. METHODS: This was a retrospective analysis of upper endoscopies performed with impedance planimetry for suspected GSS. A bariatric endoscopist, blind to impedance planimetry measurements, assessed gastric sleeve anatomy and graded GSS severity. Impedance planimetry of diameter and distensibility index (DI) were obtained using 3 different balloon volumes (30, 40, and 50 mL). RESULTS: A total of 110 upper endoscopies were included. Distribution of GSS was graded as none, mild, moderate, and severe in 19 (17%), 27 (25%), 34 (31%), and 30 (27%) procedures, respectively. In normal gastric sleeve anatomy, mean (±SD) diameter and DI measurements using consecutive balloon volumes ranged from 19.1 (±5.5) to 23.2 (±1.7) and 16.8 (±4.9) to 23.1 (±10.9), respectively. In severe GSS, mean diameter and DI measurements ranged from 10.3 (±3.0) to 16.6 (±2.1) and 7.5 (±2.4) to 7.7 (±2.4), respectively. When stratified by severity, impedance planimetry measurements of diameter and DI were significantly lower with each subsequent increase in GSS grade regardless of balloon fill volumes (P ≤ 0.001). DISCUSSION: Impedance planimetry measurements provide objective assessment in the diagnosis of GSS and correlate with luminal narrowing. A diameter ≥20 mm and a DI ≥15 mm 2/mm Hg, as measured by impedance planimetry, are predictive of normal gastric sleeve anatomy. This study provides new benchmark values for the diagnosis and severity of GSS. [ABSTRACT FROM AUTHOR]

VEGF-A is a key cytokine in tumor angiogenesis and a major therapeutic target for cancer. VEGF165 is the predominant isoform of VEGF-A, and it is the most potent angiogenesis stimulant. VEGFR2/KDR domains 2 and 3 (D2D3) bind to the N-terminal domain (NTD, residues 1-110) of VEGF165. Since removal of the heparin-binding domain (HBD, residues 111-165) markedly reduced the mitogenic activity of the growth factor, it has been proposed that the HBD plays a critical role in the mitogenicity of VEGF165. Here, we report that αvβ3 specifically bound to the isolated VEGF165 HBD but not to VEGF165 NTD. Based on docking simulation and mutagenesis, we identified several critical amino acid residues within the VEGF165 HBD required for αvβ3 binding, i.e., Arg123, Arg124, Lys125, Lys140, Arg145, and Arg149. We discovered that VEGF165 HBD binds to the KDR domain 1 (D1) and identified that Arg123 and Arg124 are critical for KDR D1 binding by mutagenesis, indicating that the KDR D1-binding and αvβ3-binding sites overlap in the HBD. Full-length VEGF165 mutant (R123A/R124A/K125A/K140A/R145A/R149A) defective in αvβ3 and KDR D1 binding failed to induce ERK1/2 phosphorylation, integrin β3 phosphorylation, and KDR phosphorylation and did not support proliferation of endothelial cells, although the mutation did not affect the KDR D2D3 interaction with VEGF165. Since β3-knockout mice are known to show enhanced VEGF165 signaling, we propose that the binding of KDR D1 to the VEGF165 HBD and KDR D2D3 binding to the VEGF165 NTD are critically involved in the potent mitogenicity of VEGF165. We propose that binding competition between KDR and αvβ3 to the VEGF165 HBD endows integrin αvβ3 with regulatory properties to act as a negative regulator of VEGF165 signaling. [ABSTRACT FROM AUTHOR]

Children's home-packed lunches to school reflect family's culinary cultures, social locations, and unique food norms. At Canadian elementary schools, children of Asian heritage sometimes experience "lunchbox shaming" – feeling embarrassed for bringing foods that are seen deviant from dominant food norms. This study explored the recollections of school lunchtime by 25 young adults (aged 17–25 years) from three largest Asian ethnocultural groups (Chinese, Indian, and Filipino) in Toronto, Canada. Two parents of the participants also joined follow-up interviews to provide their insights. Our analysis focused on four layers of meanings at micro-level (personal experiences and emotions), meso-level (family food practices, school food environment), macro-level (socio-historical discourses), and interactional-level (researchers' positionalities). Many participants recalled painful experiences being teased by classmates of their "stinky" lunch, throwing away homemade lunches, or asking parents to pack "normal" lunches to fit in. Conversely, a few shared positive memories of their lunches being praised and felt proud of their culinary heritage. Many reportedly felt a need to balance affiliation to both their home and school food cultures while growing up in Canada. We conclude by discussing the implications of the study findings for the ongoing debate on Canada's national school food program and food literacy education. [ABSTRACT FROM AUTHOR]

Simple Summary: The sociodemographic characteristics of a parent and child may predispose young children to excessive dietary sugar intake; however, there is limited research available on this topic. The aim of this cross-sectional analysis was to examine the impact of sociodemographic characteristics such as child age, child sex, child ethnicity, parent number of years living in Canada, annual household income, parent education and parent marital status on total, free and added sugar intake in young children. Dietary and sociodemographic data including 267 children from 210 families participating in the Guelph Family Health Study were examined. The results indicate that child age, child ethnicity and annual household income can play a crucial role in shaping sugar intake in young children. This research may help inform future research and program interventions early in life along with guiding parents to decrease sugar intake in young children. Background: It is crucial to develop strategies targeted to promote healthy eating patterns in vulnerable populations, especially young children from diverse sociodemographic groups. Thus, the study objective was to investigate the associations between child age, child sex, child ethnicity, parent number of years living in Canada, annual household income, parent education and parent marital status with total, free and added sugar intakes in young children. Methods: This cross-sectional study was a secondary analysis of data gathered in the Guelph Family Health Study. The study included 267 children (129M; 138F) from 210 families aged 1.5 to 5 years. Parents completed questionnaires for children on sociodemographic characteristics and an online 24-hour diet recall. The associations between sociodemographic characteristics and sugar intakes were determined using generalized estimating equations applied to linear regression models. Results: The mean age of the children was 3.5 ± 1.2 years (mean ± std dev.). As children's age increased, there was a greater intake of free and added sugar ( β ^ = 8.6, p = 0.01, 95% CI = 2.4 to 14.7 and β ^ = 6.5, p = 0.03, 95% CI = 0.8 to 12.2, respectively). Those children who identified as white had a higher total sugar intake than children of other ethnicities ( β ^ = 31.0, p = 0.01, 95% CI = 7.2 to 54.7). Additionally, higher annual household income was associated with lower was free sugar intake in children ( β ^ = −2.4, p = 0.02, 95% CI = −4.5 to −0.4). Conclusions: This study underscores the significant influence of multiple sociodemographic characteristics on sugar intake in young children, providing valuable insights for public health policy and nutrition interventions. Moreover, this study highlights the need for early behaviour interventions focusing on reducing sugar intake in young children, while considering sociodemographic factors. [ABSTRACT FROM AUTHOR]