50 research outputs found

    Development of Computable Phenotype to Identify and Characterize Transitions in Acuity Status in Intensive Care Unit

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    Background: In the United States, 5.7 million patients are admitted annually to intensive care units (ICU), with costs exceeding $82 billion. Although close monitoring and dynamic assessment of patient acuity are key aspects of ICU care, both are limited by the time constraints imposed on healthcare providers. Methods: Using the University of Florida Health (UFH) Integrated Data Repository as Honest Broker, we created a database with electronic health records data from a retrospective study cohort of 38,749 adult patients admitted to ICU at UF Health between 06/01/2014 and 08/22/2019. This repository includes demographic information, comorbidities, vital signs, laboratory values, medications with date and timestamps, and diagnoses and procedure codes for all index admission encounters as well as encounters within 12 months prior to index admission and 12 months follow-up. We developed algorithms to identify acuity status of the patient every four hours during each ICU stay. Results: We had 383,193 encounters (121,800 unique patients) admitted to the hospital, and 51,073 encounters (38,749 unique patients) with at least one ICU stay that lasted more than four hours. These patients requiring ICU admission had longer median hospital stay (7 days vs. 1 day) and higher in-hospital mortality (9.6% vs. 0.4%) compared with those not admitted to the ICU. Among patients who were admitted to the ICU and expired during hospital admission, more deaths occurred in the ICU than on general hospital wards (7.4% vs. 0.8%, respectively). Conclusions: We developed phenotyping algorithms that determined patient acuity status every four hours while admitted to the ICU. This approach may be useful in developing prognostic and clinical decision-support tools to aid patients, caregivers, and providers in shared decision-making processes regarding resource use and escalation of care.Comment: 21 Pages, that include 6 figures, 3 tables and 1 supplemental Tabl

    Applications and Perspectives of Cascade Reactions in Bacterial Infection Control

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    Cascade reactions integrate two or more reactions, of which each subsequent reaction can only start when the previous reaction step is completed. Employing natural substrates in the human body such as glucose and oxygen, cascade reactions can generate reactive oxygen species (ROS) to kill tumor cells, but cascade reactions may also have potential as a direly needed, novel bacterial infection-control strategy. ROS can disintegrate the EPS matrix of infectious biofilm, disrupt bacterial cell membranes, and damage intra-cellular DNA. Application of cascade reactions producing ROS as a new infection-control strategy is still in its infancy. The main advantages for infection-control cascade reactions include the fact that they are non-antibiotic based and induction of ROS resistance is unlikely. However, the amount of ROS generated is generally low and antimicrobial efficacies reported are still far <3-4 log units necessary for clinical efficacy. Increasing the amounts of ROS generated by adding more substrate bears the risk of collateral damage to tissue surrounding an infection site. Collateral tissue damage upon increasing substrate concentrations may be prevented by locally increasing substrate concentrations, for instance, using smart nanocarriers. Smart, pH-responsive nanocarriers can self-target and accumulate in infectious biofilms from the blood circulation to confine ROS production inside the biofilm to yield long-term presence of ROS, despite the short lifetime (nanoseconds) of individual ROS molecules. Increasing bacterial killing efficacies using cascade reaction components containing nanocarriers constitutes a first, major challenge in the development of infection-control cascade reactions. Nevertheless, their use in combination with clinical antibiotic treatment may already yield synergistic effects, but this remains to be established for cascade reactions. Furthermore, specific patient groups possessing elevated levels of endogenous substrate (for instance, diabetic or cancer patients) may benefit from the use of cascade reaction components containing nanocarriers

    Synergy between pH- and hypoxia-responsiveness in antibiotic-loaded micelles for eradicating mature, infectious biofilms

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    Antibiotic-loaded PEG/PAE-based micelles are frequently considered for eradicating infectious biofilms. At physiological pH, PEG facilitates transport through blood. Near an acidic infection-site, PAE becomes protonated causing micellar targeting to a biofilm. However, micellar penetration and accumulation is confined to the surface region of a biofilm. Especially matured biofilms also possess hypoxic regions. We here designed dual-responsive PEG/PAE-b-P(Lys-NBCF) micelles, responding to both acidity and low oxygen-saturation level in matured biofilms. Dual, pH- and hypoxia-responsive micelles targeted and accumulated evenly over the depth of 7- to 14-days old biofilms. Delineation demonstrated that pH-responsiveness was responsible for targeting of the infection-site and accumulation of micelles in the surface region of the biofilm. Hypoxia-responsiveness caused deep penetration in the biofilm. Dual, pH- and hypoxia-responsive micelles loaded with ciprofloxacin yielded more effective, synergistic eradication of 10-days old, matured Staphylococcus aureus biofilms underneath an abdominal imaging-window in living mice than achieved by ciprofloxacin in solution or single, pH- or hypoxia responsive micelles loaded with ciprofloxacin. Also, wound-healing after removal of window and its frame proceeded fastest after tail-vein injection of ciprofloxacin-loaded, dual, pH- and hypoxia-responsive micelles. Concluding, pH- and hypoxia-responsiveness are both required for eradicating mature biofilms and advancing responsive antibiotic nanocarriers to clinical application. Statement of significance: pH-responsive antibiotic nanocarriers have emerged as a possible new strategy to prevent antimicrobial-resistant bacterial infections from becoming the leading cause of death. In this paper, we show that commonly studied, pH-responsive micellar nanocarriers merely allow self-targeting to an infectious biofilm, but do not penetrate deeply into the biofilm. The dual-responsive (acidic pH- and hypoxia) antibiotic-loaded micelles designed here not only self-target to an infectious biofilm, but also penetrate deeply. The in vitro and in vivo advantages of dual-responsive nanocarriers are most obvious when studied in infectious biofilms grown for 10 viz a viz the 2 days, usually applied in the literature. Significantly, clinical treatment of bacterial infection usually starts more than 2 days after appearance of the first symptoms

    A Guanosine-Quadruplex Hydrogel as Cascade Reaction Container Consuming Endogenous Glucose for Infected Wound Treatment-A Study in Diabetic Mice

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    Diabetic foot ulcers infected with antibiotic‐resistant bacteria form a severe complication of diabetes. Antimicrobial‐loaded hydrogels are used as a dressing for infected wounds, but the ongoing rise in the number of antimicrobial‐resistant infections necessitates new, nonantibiotic based designs. Here, a guanosine‐quadruplex (G(4))‐hydrogel composed of guanosine, 2‐formylphenylboronic acid, and putrescine is designed and used as a cascade‐reaction container. The G(4)‐hydrogel is loaded with glucose‐oxidase and hemin. The first cascade‐reaction, initiated by glucose‐oxidase, transforms glucose and O(2) into gluconic acid and H(2)O(2). In vitro, this reaction is most influential on killing Staphylococcus aureus or Pseudomonas aeruginosa in suspension, but showed limited killing of bacteria in biofilm‐modes of growth. The second cascade‐reaction, however, transforming H(2)O(2) into reactive‐oxygen‐species (ROS), also enhances killing of biofilm bacteria due to hemin penetration into biofilms and interaction with eDNA G‐quadruplexes in the biofilm matrix. Therewith, the second cascade‐reaction generates ROS close to the target bacteria, facilitating killing despite the short life‐time of ROS. Healing of infected wounds in diabetic mice proceeds faster upon coverage by these G(4)‐hydrogels than by clinically common ciprofloxacin irrigation. Moreover, local glucose concentrations around infected wounds decrease. Concluding, a G(4)‐hydrogel loaded with glucose‐oxidase and hemin is a good candidate for infected wound dressings, particularly in diabetic patients

    Coating of a Novel Antimicrobial Nanoparticle with a Macrophage Membrane for the Selective Entry into Infected Macrophages and Killing of Intracellular Staphylococci

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    Internalization of Staphylococcus aureus by macrophages can inactivate bacterial killing mechanisms, allowing intracellular residence and dissemination of infection. Concurrently, these staphylococci can evade antibiotics that are frequently unable to pass mammalian cell membranes. A binary, amphiphilic conjugate composed of triclosan and ciprofloxacin is synthesized that self-assemble through micelle formation into antimicrobial nanoparticles (ANPs). These novel ANPs are stabilized through encapsulation in macrophage membranes, providing membrane-encapsulated, antimicrobial-conjugated NPs (Me-ANPs) with similar protein activity, Toll-like receptor expression and negative surface charge as their precursor murine macrophage/human monocyte cell lines. The combination of Toll-like receptors and negative surface charge allows uptake of Me-ANPs by infected macrophages/monocytes through positively charged, lysozyme-rich membrane scars created during staphylococcal engulfment. Me-ANPs are not engulfed by more negatively charged sterile cells possessing less lysozyme at their surface. The Me-ANPs kill staphylococci internalized in macrophages in vitro. Me-ANPs likewise kill staphylococci more effectively than ANPs without membrane-encapsulation or clinically used ciprofloxacin in a mouse peritoneal infection model. Similarly, organ infections in mice created by dissemination of infected macrophages through circulation in the blood are better eradicated by Me-ANPs than by ciprofloxacin. These unique antimicrobial properties of macrophage-monocyte Me-ANPs provide a promising direction for human clinical application to combat persistent infections

    Identification of BC005512 as a DNA Damage Responsive Murine Endogenous Retrovirus of GLN Family Involved in Cell Growth Regulation

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    Genotoxicity assessment is of great significance in drug safety evaluation, and microarray is a useful tool widely used to identify genotoxic stress responsive genes. In the present work, by using oligonucleotide microarray in an in vivo model, we identified an unknown gene BC005512 (abbreviated as BC, official full name: cDNA sequence BC005512), whose expression in mouse liver was specifically induced by seven well-known genotoxins (GTXs), but not by non-genotoxins (NGTXs). Bioinformatics revealed that BC was a member of the GLN family of murine endogenous retrovirus (ERV). However, the relationship to genotoxicity and the cellular function of GLN are largely unknown. Using NIH/3T3 cells as an in vitro model system and quantitative real-time PCR, BC expression was specifically induced by another seven GTXs, covering diverse genotoxicity mechanisms. Additionally, dose-response and linear regression analysis showed that expression level of BC in NIH/3T3 cells strongly correlated with DNA damage, measured using the alkaline comet assay,. While in p53 deficient L5178Y cells, GTXs could not induce BC expression. Further functional studies using RNA interference revealed that down-regulation of BC expression induced G1/S phase arrest, inhibited cell proliferation and thus suppressed cell growth in NIH/3T3 cells. Together, our results provide the first evidence that BC005512, a member from GLN family of murine ERV, was responsive to DNA damage and involved in cell growth regulation. These findings could be of great value in genotoxicity predictions and contribute to a deeper understanding of GLN biological functions

    Antidepressants as Autophagy Modulators for Cancer Therapy

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    Cancer is a major global public health problem with high morbidity. Depression is known to be a high-frequency complication of cancer diseases that decreases patients’ life quality and increases the mortality rate. Therefore, antidepressants are often used as a complementary treatment during cancer therapy. During recent decades, various studies have shown that the combination of antidepressants and anticancer drugs increases treatment efficiency. In recent years, further emerging evidence has suggested that the modulation of autophagy serves as one of the primary anticancer mechanisms for antidepressants to suppress tumor growth. In this review, we introduce the anticancer potential of antidepressants, including tricyclic antidepressants (TCAs), tetracyclic antidepressants (TeCAs), selective serotonin reuptake inhibitors (SSRIs), and serotonin-norepinephrine reuptake inhibitors (SNRIs). In particular, we focus on their autophagy-modulating mechanisms for regulating autophagosome formation and lysosomal degradation. We also discuss the prospect of repurposing antidepressants as anticancer agents. It is promising to repurpose antidepressants for cancer therapy in the future

    Fine mapping of QPm.caas-3BS, a stable QTL for adult-plant resistance to powdery mildew in wheat (Triticum aestivum L.)

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    Powdery mildew is a devastating foliar disease occurring in most wheat-growing areas. Characterization and fine mapping of genes for powdery mildew resistance can benefit marker-assisted breeding. We previously identified a stable quantitative trait locus (QTL) QPm.caas-3BS for adult-plant resistance to powdery mildew in a recombinant inbred line population of Zhou8425B/Chinese Spring by phenotyping across four environments. Using 11 heterozygous recombinants and high-density molecular markers, QPm.caas-3BS was delimited in a physical interval of approximately 3.91 Mb. Based on re-sequenced data and expression profiles, three genes TraesCS3B02G014800, TraesCS3B02G016800 and TraesCS3B02G019900 were associated with the powdery mildew resistance locus. Three gene-specific kompetitive allele-specific PCR (KASP) markers were developed from these genes and validated in the Zhou8425B derivatives and Zhou8425B/Chinese Spring population in which the resistance gene was mapped to a 0.3 cM interval flanked by KASP14800 and snp_50465, corresponding to a 431 kb region at the distal end of chromosome 3BS. Within the interval, TraesCS3B02G014800 was the most likely candidate gene for QPm.caas-3BS, but TraesCS3B02G016300 and TraesCS3B02G016400 were less likely candidates based on gene annotations and sequence variation between the parents. These results not only offer high-throughput KASP markers for improvement of powdery mildew resistance but also pave the way to map-based cloning of the resistance gene
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