An Analysis of Clinical Outcomes of Exploratory Pediatric Metformin Ingestions Reported to the Texas Poison Center Network From 2011 to 2021.

Background: Poison centers develop triage threshold guidelines for pediatric metformin ingestions. Our network uses 1700 mg, or 85 mg/kg. Objective: To describe the dose, clinical course, and outcomes for inadvertent metformin ingestions in children 5 years old and younger reported to our statewide poison center network. Methods: We searched the poison center database 2011 to 2021 for metformin ingestions in patients 5 years and younger. Variables included age, sex, weight, dose, symptoms, outcome, and more. We used descriptive statistics with medians and interquartile ranges (IQR) for continuous variables. Results: Of 669 cases, exposures by age were 208 (31.1%) 1 to 2 years, and 275 (41.1%) 2 years. Weight was recorded in 342 (51.1%) (median 13.5 kg; IQR: 3.7 kg), and dose in 149 (22.3%) (median 500 mg; IQR: 500 mg). Milligram/kilogram values were available for 103 (15.4%) with median 42.4 mg/kg, IQR: 39 mg/kg. Most (647, 98.5%) exposures were unintentional. Most (445/669, 66.5%) were managed at a non-healthcare facility, while 204 (30.7%) were already at or referred to a healthcare facility. Of these 204 patients, 169 (82.8%) were evaluated and treated at the emergency department and discharged. Four (2%) were admitted to critical care, and 7 (3.4%) to the ward. Medical outcomes by effect were 5 (0.7%) minor, 2 (0.3%) moderate, 253 (37.8%) none, 292 (43.6%) not followed (minimal effects possible), and no major effects or deaths. Of 20 clinical occurrences reported, vomiting was most common (8, 1.2%). Conclusion: Despite little recorded dosage information, pediatric metformin ingestions under 85 mg/kg had predominantly uneventful medical outcomes.

Absence of detectable monkeypox virus DNA in 11,000 English blood donations during the 2022 outbreak.

BACKGROUND: A large, worldwide outbreak of mpox (formerly referred to as monkeypox) involving mainly men who have sex with men commenced in May 2022. We evaluated the frequency of positivity for the causative agent, monkeypox virus (MPXV), in blood donations collected in August 2022, during the outbreak period in Southern England. METHODS/MATERIALS: The sensitivity and specificity of an MPXV-specific PCR and a generic non-variola orthopoxvirus (NVO) PCR were evaluated using samples from mpox cases and synthetic DNA standards. Residual minipools from nucleic acid testing were obtained from 10,896 blood donors in Southern England, with 21% from London. RESULTS: MPXV and NVO PCRs were both capable of detection of single copies of target sequence with calculated limits of detection (LOD)90 s of 2.3 and 2.1 DNA copies and analytical sample sensitivities of 46 and 42 MPXV DNA copies/ml, respectively. 454 minipools produced from 10,896 unique donors were assayed for MPXV DNA by both methods. No positive minipools were detected by either PCR. CONCLUSIONS: Although blood donors are unrepresentative of the UK population in terms of MPXV infection risk, the uniformly negative MPXV DNA testing results provide reassurance that MPXV viraemia and potential transmission risk were rare or absent in donors during the outbreak period. Minipools from blood donors allow rapid implementation of large-scale population-based screening for emerging pathogens and represent an important resource for pandemic preparedness.

VEGF signaling activates the matrix metalloproteinases, MmpL7 and MmpL5 at the sites of active skeletal growth and MmpL7 regulates skeletal elongation.

Organisms can uptake minerals, shape them in different forms and generate teeth, skeletons or shells that support and protect them. Mineral uptake, trafficking and nucleation are tightly regulated by the biomineralizing cells through networks of specialized proteins. Specifically, matrix metalloproteases (MMPs) digest various extracellular substrates and allow for mineralization in the vertebrates' teeth and bones, but little is known about their role in invertebrates' systems. The sea urchin embryo provides an excellent invertebrate model for genetic and molecular studies of biomineralization. MMP inhibition prevents the growth of the calcite spicules of the sea urchin larval skeleton, however, the molecular mechanisms and genes that underlie this response are not well understood. Here we study the spatial expression and regulation of two membrane type MMPs that were found to be occluded in the sea urchin spicules, Pl-MmpL7 and Pl-MmpL5, and investigate the function of Pl-MmpL7 in skeletogenesis. The inhibition of MMPs does not change the volume of the calcium vesicles in the skeletogenic cells. The expression of Pl-MmpL7 and Pl-MmpL5 is regulated by the Vascular Endothelial Growth Factor (VEGF) signaling, from the time of skeleton initiation and on. The expression of these genes is localized to the subsets of skeletogenic cells where active spicule growth occurs throughout skeletogenesis. Downregulation of Pl-MmpL7 expression delays the growth of the skeletal rods and in some cases, strongly perturbs skeletal shape. The localized expression of Pl-MmpL7 and Pl-MmpL5 to the active growth zone and the effect of Pl-MmpL7 perturbations on skeletal growth, suggest that these genes are essential for normal spicule elongation in the sea urchin embryo.

Calcium-vesicles perform active diffusion in the sea urchin embryo during larval biomineralization.

Biomineralization is the process by which organisms use minerals to harden their tissues and provide them with physical support. Biomineralizing cells concentrate the mineral in vesicles that they secret into a dedicated compartment where crystallization occurs. The dynamics of vesicle motion and the molecular mechanisms that control it, are not well understood. Sea urchin larval skeletogenesis provides an excellent platform for investigating the kinetics of mineral-bearing vesicles. Here we used lattice light-sheet microscopy to study the three-dimensional (3D) dynamics of calcium-bearing vesicles in the cells of normal sea urchin embryos and of embryos where skeletogenesis is blocked through the inhibition of Vascular Endothelial Growth Factor Receptor (VEGFR). We developed computational tools for displaying 3D-volumetric movies and for automatically quantifying vesicle dynamics. Our findings imply that calcium vesicles perform an active diffusion motion in both, calcifying (skeletogenic) and non-calcifying (ectodermal) cells of the embryo. The diffusion coefficient and vesicle speed are larger in the mesenchymal skeletogenic cells compared to the epithelial ectodermal cells. These differences are possibly due to the distinct mechanical properties of the two tissues, demonstrated by the enhanced f-actin accumulation and myosinII activity in the ectodermal cells compared to the skeletogenic cells. Vesicle motion is not directed toward the biomineralization compartment, but the vesicles slow down when they approach it, and probably bind for mineral deposition. VEGFR inhibition leads to an increase of vesicle volume but hardly changes vesicle kinetics and doesn't affect f-actin accumulation and myosinII activity. Thus, calcium vesicles perform an active diffusion motion in the cells of the sea urchin embryo, with diffusion length and speed that inversely correlate with the strength of the actomyosin network. Overall, our studies provide an unprecedented view of calcium vesicle 3D-dynamics and point toward cytoskeleton remodeling as an important effector of the motion of mineral-bearing vesicles.

The biological regulation of sea urchin larval skeletogenesis - From genes to biomineralized tissue.

Biomineralization is the process in which soft organic tissues use minerals to produce shells, skeletons and teeth for various functions such as protection and physical support. The ability of the cells to control the time and place of crystal nucleation as well as crystal orientation and stiffness is far beyond the state-of-the art of human technologies. Thus, understanding the biological control of biomineralization will promote our understanding of embryo development as well as provide novel approaches for material engineering. Sea urchin larval skeletogenesis offers an excellent platform for functional analyses of both the molecular control system and mineral uptake and deposition. Here we describe the current understanding of the genetic, molecular and cellular processes that underlie sea urchin larval skeletogenesis. We portray the regulatory genes that define the specification of the skeletogenic cells and drive the various morphogenetic processes that occur in the skeletogenic lineage, including: epithelial to mesenchymal transition, cell migration, spicule cavity formation and mineral deposition into the spicule cavity. We describe recent characterizations of the size, motion and mineral concentration of the calcium-bearing vesicles in the skeletogenic cells. We review the distinct specification states within the skeletogenic lineage that drive localized skeletal growth at the tips of the spicules. Finally, we discuss the surprising similarity between the regulatory network and cellular processes that drive sea urchin skeletogenesis and those that control vertebrate vascularization. Overall, we illustrate the novel insights on the biological regulation and evolution of biomineralization, gained from studies of the sea urchin larval skeletogenesis.

Hydra image processor: 5-D GPU image analysis library with MATLAB and python wrappers.

SUMMARY: Light microscopes can now capture data in five dimensions at very high frame rates producing terabytes of data per experiment. Five-dimensional data has three spatial dimensions (x, y, z), multiple channels (λ) and time (t). Current tools are prohibitively time consuming and do not efficiently utilize available hardware. The hydra image processor (HIP) is a new library providing hardware-accelerated image processing accessible from interpreted languages including MATLAB and Python. HIP automatically distributes data/computation across system and video RAM allowing hardware-accelerated processing of arbitrarily large images. HIP also partitions compute tasks optimally across multiple GPUs. HIP includes a new kernel renormalization reducing boundary effects associated with widely used padding approaches. AVAILABILITY AND IMPLEMENTATION: HIP is free and open source software released under the BSD 3-Clause License. Source code and compiled binary files will be maintained on http://www.hydraimageprocessor.com. A comprehensive description of all MATLAB and Python interfaces and user documents are provided. HIP includes GPU-accelerated support for most common image processing operations in 2-D and 3-D and is easily extensible. HIP uses the NVIDIA CUDA interface to access the GPU. CUDA is well supported on Windows and Linux with macOS support in the future.

Cyclophilins: Less Studied Proteins with Critical Roles in Pathogenesis.

Cyclophilins (EC 5.2.1.8) belong to a subgroup of proteins known as immunophilins, which also include FK506-binding proteins and parvulins. Members of the immunophilins have two main characteristic properties: (i) peptidyl-prolyl cis-trans isomerase activity and (ii) the ability to bind immunosuppressant molecules of fungal origin. Cyclophilins are some of the most conserved proteins present in eukaryotes and prokaryotes, and they have been implicated in diverse cellular processes and responses to multiple biotic and abiotic stresses. Cyclophilins have been exploited in humans and plants extensively, but they have only recently received attention in regard to phytopathogens. In Phellinus sulphurascens and species of the genus Leptosphaeria and Phytophthora, high expression of cyclophilins was found to be related to infection. Moreover, recent studies of cyclophilins in certain phytopathogens, such as Magnaporthe oryzae, Botrytis cinerea, Cryphonectria parasitica, and Puccinia triticina, demonstrated their roles as a pathogenicity factors. In addition to pathogenicity, cyclophilins have high affinity for the immunosuppressive drug cyclosporin A, which is a potent antifungal agent. Although cyclophilins are highly conserved in phytopathogens, because they have been less studied, their role remains largely unknown. In this review, we provide detailed information on the cyclophilins in several phytopathogens, including fungi and oomycetes, as well as their role in suppressing plant immunity.

Objective comparison of particle tracking methods.

Particle tracking is of key importance for quantitative analysis of intracellular dynamic processes from time-lapse microscopy image data. Because manually detecting and following large numbers of individual particles is not feasible, automated computational methods have been developed for these tasks by many groups. Aiming to perform an objective comparison of methods, we gathered the community and organized an open competition in which participating teams applied their own methods independently to a commonly defined data set including diverse scenarios. Performance was assessed using commonly defined measures. Although no single method performed best across all scenarios, the results revealed clear differences between the various approaches, leading to notable practical conclusions for users and developers.

LEVER: software tools for segmentation, tracking and lineaging of proliferating cells.

The analysis of time-lapse images showing cells dividing to produce clones of related cells is an important application in biological microscopy. Imaging at the temporal resolution required to establish accurate tracking for vertebrate stem or cancer cells often requires the use of transmitted light or phase-contrast microscopy. Processing these images requires automated segmentation, tracking and lineaging algorithms. There is also a need for any errors in the automated processing to be easily identified and quickly corrected. We have developed LEVER, an open source software tool that combines the automated image analysis for phase-contrast microscopy movies with an easy-to-use interface for validating the results and correcting any errors. AVAILABILITY AND IMPLEMENTATION: LEVER is available free and open source, licensed under the GNU GPLv3. Details on obtaining and using LEVER are available at http://n2t.net/ark:/87918/d9rp4t CONTACT: acohen@coe.drexel.edu.

Visualization and correction of automated segmentation, tracking and lineaging from 5-D stem cell image sequences.

BACKGROUND: Neural stem cells are motile and proliferative cells that undergo mitosis, dividing to produce daughter cells and ultimately generating differentiated neurons and glia. Understanding the mechanisms controlling neural stem cell proliferation and differentiation will play a key role in the emerging fields of regenerative medicine and cancer therapeutics. Stem cell studies in vitro from 2-D image data are well established. Visualizing and analyzing large three dimensional images of intact tissue is a challenging task. It becomes more difficult as the dimensionality of the image data increases to include time and additional fluorescence channels. There is a pressing need for 5-D image analysis and visualization tools to study cellular dynamics in the intact niche and to quantify the role that environmental factors play in determining cell fate. RESULTS: We present an application that integrates visualization and quantitative analysis of 5-D (x,y,z,t,channel) and large montage confocal fluorescence microscopy images. The image sequences show stem cells together with blood vessels, enabling quantification of the dynamic behaviors of stem cells in relation to their vascular niche, with applications in developmental and cancer biology. Our application automatically segments, tracks, and lineages the image sequence data and then allows the user to view and edit the results of automated algorithms in a stereoscopic 3-D window while simultaneously viewing the stem cell lineage tree in a 2-D window. Using the GPU to store and render the image sequence data enables a hybrid computational approach. An inference-based approach utilizing user-provided edits to automatically correct related mistakes executes interactively on the system CPU while the GPU handles 3-D visualization tasks. CONCLUSIONS: By exploiting commodity computer gaming hardware, we have developed an application that can be run in the laboratory to facilitate rapid iteration through biological experiments. We combine unsupervised image analysis algorithms with an interactive visualization of the results. Our validation interface allows for each data set to be corrected to 100% accuracy, ensuring that downstream data analysis is accurate and verifiable. Our tool is the first to combine all of these aspects, leveraging the synergies obtained by utilizing validation information from stereo visualization to improve the low level image processing tasks.

Chemdex: quantification and distributions of valence numbers, oxidation numbers, coordination numbers, electron numbers, and covalent bond classes for the elements.

The paper introduces Chemdex, a freely accessible web-based database of over 70 000 compounds characterised by crystallography from across the periodic table. Its software calculates for an atom of interest within each compound classifications including valence number, oxidation number, coordination number, electron number, several covalent bond classifications, and the attached atom set. Users may explore distributions of these classifications by percentages and heat map displays for individual elements or sets of elements, or in several cases for one classification plotted against a second. These properties often display clear periodicity. Based upon distributions across the periodic table of valence numbers, electron numbers, coordination numbers, and attached atom data suggestions are made regarding the placement of hydrogen in the periodic table, membership of group 3 in the periodic table, locations of the early actinoids in the periodic table, and assignments of certain elements as metalloids.

ROCK and the actomyosin network control biomineral growth and morphology during sea urchin skeletogenesis.

Biomineralization had apparently evolved independently in different phyla, using distinct minerals, organic scaffolds, and gene regulatory networks (GRNs). However, diverse eukaryotes from unicellular organisms, through echinoderms to vertebrates, use the actomyosin network during biomineralization. Specifically, the actomyosin remodeling protein, Rho-associated coiled-coil kinase (ROCK) regulates cell differentiation and gene expression in vertebrates' biomineralizing cells, yet, little is known on ROCK's role in invertebrates' biomineralization. Here, we reveal that ROCK controls the formation, growth, and morphology of the calcite spicules in the sea urchin larva. ROCK expression is elevated in the sea urchin skeletogenic cells downstream of the Vascular Endothelial Growth Factor (VEGF) signaling. ROCK inhibition leads to skeletal loss and disrupts skeletogenic gene expression. ROCK inhibition after spicule formation reduces the spicule elongation rate and induces ectopic spicule branching. Similar skeletogenic phenotypes are observed when ROCK is inhibited in a skeletogenic cell culture, indicating that these phenotypes are due to ROCK activity specifically in the skeletogenic cells. Reduced skeletal growth and enhanced branching are also observed under direct perturbations of the actomyosin network. We propose that ROCK and the actomyosin machinery were employed independently, downstream of distinct GRNs, to regulate biomineral growth and morphology in Eukaryotes.

GluK1 antagonists from 6-(carboxy)phenyl decahydroisoquinoline derivatives. SAR and evaluation of a prodrug strategy for oral efficacy in pain models.

The synthesis and structure-activity relationship of decahydroisoquinoline derivatives with various benzoic acid substitutions as GluK1 antagonists are described. Potent and selective antagonists were selected for a tailored prodrug approach in order to facilitate the evaluation of the new compounds in pain models after oral administration. Several diester prodrugs allowed for acceptable amino acid exposure and moderate efficacy in vivo.

GluK1 antagonists from 6-(tetrazolyl)phenyl decahydroisoquinoline derivatives: in vitro profile and in vivo analgesic efficacy.

We have explored the decahydroisoquinoline scaffold, bearing a phenyl tetrazole, as GluK1 antagonists with potential as oral analgesics. We have established the optimal linker atom between decahydroisoquinoline and phenyl rings and demonstrated an improvement of both the affinity for the GluK1 receptor and the selectivity against the related GluA2 receptor with proper phenyl substitution. In this Letter, we also disclose in vivo data that led to the discovery of LY545694·HCl, a compound with oral efficacy in two persistent pain models.

Mechanisms regulating grain contamination with trichothecenes translocated from the stem base of wheat (Triticum aestivum) infected with Fusarium culmorum.

Factors limiting trichothecene contamination of mature wheat grains after Fusarium infection are of major interest in crop production. In addition to ear infection, systemic translocation of deoxynivalenol (DON) may contribute to mycotoxin levels in grains after stem base infection with toxigenic Fusarium spp. However, the exact and potential mechanisms regulating DON translocation into wheat grains from the plant base are still unknown. We analyzed two wheat cultivars differing in susceptibility to Fusarium head blight (FHB), which were infected at the stem base with Fusarium culmorum in climate chamber experiments. Fungal DNA was found only in the infected stem base tissue, whereas DON and its derivative, DON-3-glucoside (D3G), were detected in upper plant parts. Although infected stem bases contained more than 10,000 µg kg⁻¹ dry weight (DW) of DON and mean levels of DON after translocation in the ear and husks reached 1,900 µg kg⁻¹ DW, no DON or D3G was detectable in mature grains. D3G quantification revealed that DON detoxification took mainly place in the stem basis, where ≤ 50% of DON was metabolized into D3G. Enhanced expression of a gene putatively encoding a uridine diphosphate-glycosyltransferase (GenBank accession number FG985273) was observed in the stem base after infection with F. culmorum. Resistance to F. culmorum stem base infection, DON glycosylation in the stem base, and mycotoxin translocation were unrelated to cultivar resistance to FHB. Histological studies demonstrated that the vascular transport of DON labeled with fluorescein as a tracer from the peduncle to the grain was interrupted by a barrier zone at the interface between grain and rachilla, formerly described as "xylem discontinuity". This is the first study to demonstrate the effective control of influx of systemically translocated fungal mycotoxins into grains at the rachilla-seed interface by the xylem discontinuity tissue in wheat ears.

Generation of Rab-based transgenic lines for in vivo studies of endosome biology in zebrafish.

The Rab family of small GTPases function as molecular switches regulating membrane and protein trafficking. Individual Rab isoforms define and are required for specific endosomal compartments. To facilitate in vivo investigation of specific Rab proteins, and endosome biology in general, we have generated transgenic zebrafish lines to mark and manipulate Rab proteins. We also developed software to track and quantify endosome dynamics within time-lapse movies. The established transgenic lines ubiquitously express EGFP fusions of Rab5c (early endosomes), Rab11a (recycling endosomes), and Rab7 (late endosomes) to study localization and dynamics during development. Additionally, we generated UAS-based transgenic lines expressing constitutive active (CA) and dominant-negative (DN) versions for each of these Rab proteins. Predicted localization and functional consequences for each line were verified through a variety of assays, including lipophilic dye uptake and Crumbs2a localization. In summary, we have established a toolset for in vivo analyses of endosome dynamics and functions.

Heart Block Initiated by Candlenut Ingestion.

The candlenut tree is a tropical plant that has a vast number of uses which include fertilizer, dye, ink for tattooing, and fuel. The inner seed of the nut is the most utilized portion of the plant and is often sold as a food additive, natural laxative, or a weight loss supplement. Unfortunately, the seed itself is very toxic when consumed whole and in its raw state. Typical symptoms of toxicity include abdominal pain, vomiting, and diarrhea. Rarely, it can cause cardiac dysrhythmias, most commonly bradycardia and atrioventricular heart block. We present a case of a young adult female with no significant past medical history who developed typical symptoms of toxicity, as well as atrioventricular heart block following ingestion of a candlenut. Most documented cases describe complete resolution of gastrointestinal and cardiac symptoms about one week following ingestion; however, treatment while inpatient can consist of inotropes or vasopressor support, intravenous fluid hydration, electrolyte replacement, and antiemetics. Although the mechanism of action remains unclear, this report provides physicians with an understanding of the risks of ingestion and the knowledge of typical management of the toxic effects of the candlenut.

LEVERSC: Cross-Platform Scriptable Multichannel 3-D Visualization for Fluorescence Microscopy Images.

We describe a new open-source program called LEVERSC to address the challenges of visualizing the multi-channel 3-D images prevalent in biological microscopy. LEVERSC uses a custom WebGL hardware-accelerated raycasting engine unique in its combination of rendering quality and performance, particularly for multi-channel data. Key features include platform independence, quantitative visualization through interactive voxel localization, and reproducible dynamic visualization via the scripting interface. LEVERSC is fully scriptable and interactive, and works with MATLAB, Python and Java/ImageJ.

Guidelines for the laboratory investigation of heritable disorders of platelet function.

The guideline writing group was selected to be representative of UK-based medical experts. MEDLINE was systematically searched for publications in English up to the Summer of 2010 using key words platelet, platelet function testing and platelet aggregometry. Relevant references generated from initial papers and published guidelines/reviews were also examined. Meeting abstracts were not included. The writing group produced the draft guideline, which was subsequently revised and agreed by consensus. Further comment was made by members of the Haemostasis and Thrombosis Task Force of the British Committee for Standards in Haematology. The guideline was then reviewed by a sounding board of approximately 40 UK haematologists, the British Committee for Standards in Haematology (BCSH) and the British Society for Haematology Committee and comments incorporated where appropriate. Criteria used to quote levels and grades of evidence are as outlined in appendix 7 of the Procedure for Guidelines Commissioned by the BCSH [http://www.bcshguidelines.com/BCSH_PROCESS/EVIDENCE_LEVELS_AND_GRADES_OF_RECOMMENDATION/43_GRADE.html]. The objective of this guideline is to provide healthcare professionals with clear guidance on platelet function testing in patients with suspected bleeding disorders. The guidance may not be appropriate to patients receiving antiplatelet therapy and in all cases individual patient circumstances may dictate an alternative approach.

Endothelial junctional membrane protrusions serve as hotspots for neutrophil transmigration.

Upon inflammation, leukocytes rapidly transmigrate across the endothelium to enter the inflamed tissue. Evidence accumulates that leukocytes use preferred exit sites, alhough it is not yet clear how these hotspots in the endothelium are defined and how they are recognized by the leukocyte. Using lattice light sheet microscopy, we discovered that leukocytes prefer endothelial membrane protrusions at cell junctions for transmigration. Phenotypically, these junctional membrane protrusions are present in an asymmetric manner, meaning that one endothelial cell shows the protrusion and the adjacent one does not. Consequently, leukocytes cross the junction by migrating underneath the protruding endothelial cell. These protrusions depend on Rac1 activity and by using a photo-activatable Rac1 probe, we could artificially generate local exit-sites for leukocytes. Overall, we have discovered a new mechanism that uses local induced junctional membrane protrusions to facilitate/steer the leukocyte escape/exit from inflamed vessel walls.