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OBJECTIVES: Evaluate associations between volatile organic compounds (VOCs) in heat and moisture exchange (HME) filters and the presence of ventilator-associated pneumonia (VAP). SUMMARY BACKGROUND DATA: Clinical diagnostic criteria for VAP have poor inter-observer reliability, and cultures are slow to result. Exhaled breath contains VOCs related to Gram-negative bacterial proliferation, the most identified organisms in VAP. We hypothesized that exhaled VOCs on HME filters can predict nascent VAP in mechanically ventilated ICU patients. METHODS: Gas chromatography-mass spectrometry (GC-MS) was used to analyze 111 heat and moisture exchange (HME) filters from 12 intubated patients who developed VAP. Identities and relative amounts of VOCs were associated with dates of clinical suspicion and culture confirmation of VAP. Matched pairs t-tests were performed to compare VOC abundances in HME filters collected within three days pre- and post-clinical suspicion of VAP (pneumonia days), versus outside of these days (non-pneumonia days). A ROC curve was generated to determine the diagnostic potential of VOCs. RESULTS: Carbon disulfide, associated with the proliferation of certain Gram-negative bacteria, was found in samples collected during pneumonia days for 11 of 12 patients. Carbon disulfide levels were significantly greater (P=0.0163) for filters on pneumonia days. The AUROC for carbon disulfide was 0.649 (95%CI 0.419-0.88). CONCLUSIONS: Carbon disulfide associated with Gram-negative VAP can be identified on HME filters up to three days prior to the initial clinical suspicion, and approximately a week prior to culture confirmation. This suggests VOC sensors may have potential as an adjunctive method for early detection of VAP.
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BACKGROUND: Exposures to polyaromatic hydrocarbons (PAHs) contribute to cancer in the fire service. Fire investigators are involved in evaluations of post-fire scenes. In the US, it is estimated that there are up to 9000 fire investigators, compared to approximately 1.1 million total firefighting personnel. This exploratory study contributes initial evidence of PAH exposures sustained by this understudied group using worn silicone passive samplers. OBJECTIVES: Evaluate PAH exposures sustained by fire investigators at post-fire scenes using worn silicone passive samplers. Assess explanatory factors and health risks of PAH exposure at post-fire scenes. METHODS: As part of a cross-sectional study design, silicone wristbands were distributed to 16 North Carolina fire investigators, including eight public, seven private, and one public and private. Wristbands were worn during 46 post-fire scene investigations. Fire investigators completed pre- and post-surveys providing sociodemographic, occupational, and post-fire scene characteristics. Solvent extracts from wristbands were analyzed via gas chromatography-mass spectrometry (GC-MS). Results were used to estimate vapor-phase PAH concentration in the air at post-fire scenes. RESULTS: Fire investigations lasted an average of 148â¯minutes, standard deviation ± 93â¯minutes. A significant positive correlation (r=0.455, p<.001) was found between investigation duration and PAH concentrations on wristbands. Significantly greater time-normalized PAH exposures (p=0.039) were observed for investigations of newer post-fire scenes compared to older post-fire scenes. Regulatory airborne PAH exposure limits were exceeded in six investigations, based on exposure to estimated vapor-phase PAH concentrations in the air at post-fire scenes. DISCUSSION: Higher levels of off-gassing and suspended particulates at younger post-fire scenes may explain greater PAH exposure. Weaker correlations are found between wristband PAH concentration and investigation duration at older post-fire scenes, suggesting reduction of off-gassing PAHs over time. Exceedances of regulatory PAH limits indicate a need for protection against vapor-phase contaminants, especially at more recent post-fire scenes.
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Bombeiros , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Silicones , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Exposição Ocupacional/análise , Estudos Transversais , North Carolina , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Monitoramento Ambiental/métodos , Poluentes Ocupacionais do Ar/análise , Cromatografia Gasosa-Espectrometria de Massas , PunhoRESUMO
Stem cell therapy holds significant potential for many inflammatory diseases and regenerative medicine applications. However, delivery of therapeutic cells to specific disease sites after systemic administration without indiscriminate trafficking to other non-target tissues is a major limitation of current cell therapies. Here, we describe a novel nanocarrier-directed targeted cell delivery system that enables cell surface coating with dendrimer nanocarriers containing adhesion moieties to serve as a global positioning system "GPS" to guide circulating cells to targeted lesions and mediate the anchoring of cells at the inflammation site. By exploiting cell surface ligands/receptors selectively and/or molecular moieties that are highly expressed on activated endothelium in pathologic disease states, nanocarrier-coated cells containing the counterpart binding receptors/ligands can be enabled to specifically traffic to and dock at vasculature within target lesions. We demonstrate the efficacy of the I-domain fragment of LFA-1 ( id LFA-1) complexed to modified nanocarriers to facilitate homing of mesenchymal stem cells (MSCs) to inflamed luminal endothelial cells on which ICAM-1 is highly expressed in a murine model of aortic atherosclerosis. Our method can overcome challenges imposed by the high velocity and dynamic circulatory flow of the aorta to successfully deliver MSCs to atherosclerotic regions and allow for docking of the potentially therapeutic and immunomodulating cells. This targeted cell-delivery platform can be tailored for selective systemic delivery of various types of therapeutic cells to different disease areas.
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Prostate cancer (PCa) is the most frequent and second-lethal cancer among men. Despite considerable efforts to explore treatments like autologous cellular immunotherapy and immune checkpoint inhibitors, their success remains limited. The intricate tumor microenvironment (TME) and its interaction with the immune system pose significant challenges in PCa treatment. Consequently, researchers have directed their focus on augmenting the immune system's anti-tumor response by targeting the STimulator of the Interferon Genes (STING) pathway. The STING pathway is activated when foreign DNA is detected in the cytoplasm of innate immune cells, resulting in the activation of endoplasmic reticulum (ER) STING. This, in turn, triggers an augmentation of signaling, leading to the production of type I interferon (IFN) and other pro-inflammatory cytokines. Numerous studies have demonstrated that activation of the STING pathway induces immune system rejection and targeted elimination of PCa cells. Researchers have been exploring various methods to activate the STING pathway, including the use of bacterial vectors to deliver STING agonists and the combination of radiation therapy with STING agonists. Achieving effective radiation therapy with minimal side effects and optimal anti-tumor immune responses necessitates precise adjustments to radiation dosing and fractionation schedules. This comprehensive review discusses promising findings from studies focusing on activating the STING pathway to combat PCa. The STING pathway exhibits the potential to serve as an effective treatment modality for PCa, offering new hope for improving the lives of those affected by this devastating disease.
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A portable, field deployable whole-cell biosensor was developed that can withstand the complex matrices of soil and requires minimal to no sample preparation to monitor bioavailable concentrations of the essential micronutrient copper (II). Conventional measurement of micronutrients is often complex, laboratory-based, and not suitable for monitoring their bioavailable concentration. To address this need, we developed a fluorescence based microbial whole-cell biosensing (MWCB) system encoding for a Cu2+-responsive protein capable of generating a signal upon binding to Cu2+. The sensing-reporting protein was designed by performing circular permutation on the green fluorescent protein (GFP) followed by insertion of a Cu2+ binding motif into the structure of GFP. The design included insertion of several binding motifs and creating plasmids that encoded the corresponding sensing proteins. The signal generated by the sensing-reporting protein is directly proportional to the concentration of Cu2+ in the sample. Evaluation of the resulting biosensing systems carrying these plasmids was performed prior to selection of the optimal fluorescence emitting Cu2+-binding protein. The resulting optimized biosensing system was encapsulated in polyacrylate-alginate beads and embedded in soil for detection of the analyte. Once exposed to the soil, the beads were interrogated to measure the fluorescence signal emitted by the sensing-reporting protein using a portable imaging device. The biosensor was optimized for detection of Cu2+ in terms of selectivity, sensitivity, matrix effects, detection limits, and reproducibility in both liquid and soil matrices. The limit of detection (LoD) of the optimized encapsulated biosensor was calculated as 0.27 mg/L and 1.26 mg/kg of Cu2+ for Cu2+ in solution and soil, respectively. Validation of the portable imaging tools as a potential biosensing device in the field was performed.
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Cervical cancers constitute a large disease burden in developing countries, with the human papillomavirus (HPV) being responsible for most cervical lesions. Many regions in low-resource countries lack adequate access to sensitive point-of-care (POC) screening tools, preventing timely diagnosis and treatment. To reduce screening barriers, we developed a POC HPV molecular test that detects 14 high-risk HPV types in 30 min in a single assay. We introduced innovations to the underlying amplification (recombinase polymerase amplification) and detection methodologies such as improved probe design, reagent lyophilization, and pipette-less processing to increase sensitivity while enabling minimally trained personnel to conduct reproducible testing. Based on 198 clinically derived samples, we demonstrated a sensitivity of 93% and a specificity of 73% compared to an FDA-approved polymerase chain reaction-based clinical method. Our modified pipette-less simplified assay had a sensitivity of 96% and a specificity of 83%. The application of our assay is intended as a near-patient screening tool with further evaluation by a clinician for confirmation.
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Papillomavirus Humano , Infecções por Papillomavirus , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Infecções por Papillomavirus/diagnóstico , Testes Imediatos , GenótipoRESUMO
This research introduces a novel pipeline that couples machine learning (ML), and molecular docking for accelerating the process of small peptide ligand screening through the prediction of peptide-protein docking. Eight ML algorithms were analyzed for their potential. Notably, Light Gradient Boosting Machine (LightGBM), despite having comparable F1-score and accuracy to its counterparts, showcased superior computational efficiency. LightGBM was used to classify peptide-protein docking performance of the entire tetrapeptide library of 160,000 peptide ligands against four viral envelope proteins. The library was classified into two groups, 'better performers' and 'worse performers'. By training the LightGBM algorithm on just 1% of the tetrapeptide library, we successfully classified the remaining 99%with an accuracy range of 0.81-0.85 and an F1-score between 0.58-0.67. Three different molecular docking software were used to prove that the process is not software dependent. With an adjustable probability threshold (from 0.5 to 0.95), the process could be accelerated by a factor of at least 10-fold and still get 90-95% concurrence with the method without ML. This study validates the efficiency of machine learning coupled to molecular docking in rapidly identifying top peptides without relying on high-performance computing power, making it an effective tool for screening potential bioactive compounds.
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Peptídeos , Proteínas , Ligantes , Simulação de Acoplamento Molecular , Proteínas/química , Peptídeos/metabolismo , Algoritmos , Aprendizado de Máquina , Ligação ProteicaRESUMO
A biosensor was engineered to enable the study of the novel quorum sensing molecule (QSM), 3,5-dimethylpyrazin-2-ol (DPO), employed by Vibrio cholerae to regulate biofilm formation and virulence factor production. Investigations into bacterial quorum sensing (QS), a form of communication based on the production and detection of QSMs to coordinate gene expression in a population dependent manner, offer a unique window to study the molecular underpinnings of microbial behavior and host interactions. Herein, we report the construction of an engineered microbial whole-cell bioluminescent biosensing system that incorporates the recognition of the VqmA regulatory protein of Vibrio cholerae with the bioluminescent reporting signal of luciferase for the selective, sensitive, stable, and reproducible detection of DPO in a variety of samples. Importantly, using our newly developed biosensor our studies demonstrate the detection of DPO in rodent and human samples. Employing our developed biosensor should help enable elucidation of microbial behavior at the molecular level and its impact in health and disease.
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Técnicas Biossensoriais , Vibrio cholerae , Humanos , Animais , Percepção de Quorum/genética , Vibrio cholerae/genética , Pirazinas/metabolismo , Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genéticaRESUMO
Rapid on-site diagnosis of emerging pathogens is key for early identification of infected individuals and for prevention of further spreading in a population. Currently available molecular diagnostic tests are instrument-based whereas rapid antibody and antigen tests are often not sufficiently sensitive for detection in pre-symptomatic subjects. There is a need for rapid point of care molecular screening tests that can be easily adapted to emerging pathogens and are selective, sensitive, reliable in different settings around the world. We have developed a simple, rapid (<30 âmin), and inexpensive test for SARS-CoV-2 that is based on combination of isothermal reverse transcription recombinase polymerase amplification (RT-RPA) using modified primers and visual detection with paper-based microfluidics. Our test (CoRapID) is specific for SARS-CoV-2 (alpha to omicron variants) and does not detect other coronaviruses and pathogens by in silico and in vitro analysis. A two-step test protocol was developed with stable lyophilized reagents that reduces handling by using portable and disposable components (droppers, microapplicators/swabs, paper-strips). After optimization of assay components and conditions, we have achieved a limit of detection (LoD) of 1 copy/reaction by adding a blocking primer to the lateral flow assay. Using a set of 138 clinical samples, a sensitivity of 88.1% (P â< â0.05, CI: 78.2-93.8%) and specificity of 93.9% (P â< â0.05, CI: 85.4-97.6%) was determined. The lack of need for instrumentation for our CoRapID makes it an ideal on-site primary screening tool for local hospitals, doctors' offices, senior homes, workplaces, and in remote settings around the world that often do not have access to clinical laboratories.
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In vivo imaging has enabled impressive advances in biological research, both preclinical and clinical, and researchers have an arsenal of imaging methods available. Bioluminescence imaging is an advantageous method for in vivo studies that allows for the simple acquisition of images with low background signals. Researchers have increasingly been looking for ways to improve bioluminescent imaging for in vivo applications, which we sought to achieve by developing a bioluminescent probe that could specifically target cells of interest. We chose pancreatic ductal adenocarcinoma (PDAC) as the disease model because it is the most common type of pancreatic cancer and has an extremely low survival rate. We targeted the epidermal growth factor receptor (EGFR), which is frequently overexpressed in pancreatic cancer cells, using an EGFR-specific affibody to selectively identify PDAC cells and delivered a Gaussia luciferase (GLuc) bioluminescent protein for imaging by engineering a fusion protein with both the affibody and the bioluminescent protein. This fusion protein was then complexed with a G5-PAMAM dendrimer nanocarrier. The dendrimer was used to improve the protein stability in vivo and increase signal strength. Our targeted bioluminescent complex had an enhanced uptake into PDAC cells in vitro and localized to PDAC tumors in vivo in pancreatic cancer xenograft mice. The bioluminescent complexes could delineate the tumor shape, identify multiple masses, and locate metastases. Through this work, an EGFR-targeted bioluminescent-dendrimer complex enabled the straightforward identification and imaging of pancreatic cancer cells in vivo in preclinical models. This argues for the targeted nanocarrier-mediated delivery of bioluminescent proteins as a way to improve in vivo bioluminescent imaging.
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Despite fluorescent quenching with graphene oxide (GO) having shown great success in various applications - bioluminescent quenching has not yet been demonstrated using GO as a quencher. To explore the ability of GO to quench bioluminescence, we used Gaussia luciferase (Gluc) as a donor and GO as a quencher and demonstrated its application in sensing of two target analytes, HIV-1 DNA and IFN-γ. We demonstrated that the incubation of Gluc conjugated HIV-1 and IFN-γ oligonucleotide probes with GO provided for monitoring of probe-target interactions based on bioluminescence measurement in a solution phase sensing system. The limits of detection obtained for IFN-γ and HIV-1 DNA detection were 17â nM and 7.59â nM, respectively. Both sensing systems showed selectivity toward the target analyte. The detection of IFN-γ in saliva matrix was demonstrated. The use of GO as a quencher provides for high sensitivity while maintaining the selectivity of designed probes to their respective targets. The use of GO as a quencher provides for an easy assay design and low cost, environmentally friendly reporter.
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Grafite , HIV-1 , Proteínas Luminescentes , Medições LuminescentesRESUMO
Enzyme linked immunosorbent assay (ELISA) is one of the most utilized serological methods to diagnose and identify etiologic agents of many infectious diseases and other physiologically important analytes. ELISA can be used either alone or adjunct to other diagnostic methods such as molecular arrays, and other serological techniques. Most ELISA assays utilize reagents that are proteinaceous in nature, which are not very stable and require cold-chain transport systems. Development of a desirable immunoassay requires stability of reagents used and its ability to be stored at room temperature without sacrificing the activity of the reagents or the protein of interest. Metal organic frameworks (MOFs) are a rapidly emerging and evolving class of porous polymeric materials used in a variety of biosensor applications. In this study, we introduce the use of MOFs to stabilize a universal reporter fusion protein, specifically, avidin-like protein (Tam-avidin2) and the small bioluminescent protein Gaussia luciferase (Gluc) forming the fusion reporter, tamavidin2-Gluc (TA2-Gluc). This fusion protein serves as a universal reporter for any assays that utilize biotin-avidin binding strategy. Using SARS-CoV2 S1 spike antigen as the model target antigen, we demonstrated that encapsulation of TA2-Gluc fusion protein using a nano-porous material, zeolitic imidazolate framework-8 (ZIF-8), allows us to store and preserve this reporter protein at room temperature for over 6 months and use it as a reporter for an ELISA assay. Our optimized assay was validated demonstrating a 0.26 µg mL-1 limit of detection, high reproducibility of assay over days, detection of spiked non-virulent SARS-COV2 pseudovirus in real sample matrix, and detection in real COVID-19 infected individuals. This result can lead to the utilization of our TA2-Gluc fusion protein reporter with other assays and potentially in diagnostic technologies in a point-of-care setting.
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Crohn's disease (CD) is an idiopathic inflammatory condition of the gastrointestinal tract with the primary method of diagnosis and follow-up being colonoscopy. A disturbed host-microbiome interaction, including the presence of pathobionts, is implicated in initiation and perpetuation of inflammation. As such, we hypothesized that bacterial quorum-sensing (QS) molecules (QSMs), small molecules bacteria generate to regulate gene expression, would be elevated in patients with CD. We collected serum at the time of colonoscopy from patients with CD and healthy controls, determining through biosensors for QSMs that patients with CD had significantly elevated levels of QSMs in serum. Expansion of these studies may allow for QSM levels in serum to serve as a biomarker for intestinal inflammation in patients with CD.
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Doença de Crohn , Humanos , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/microbiologia , Bactérias , Inflamação , Gerenciamento ClínicoRESUMO
There is an unmet need for a point-of-care test that is accurate, affordable, and simple to diagnose bacterial vaginosis, the most common cause of vaginal symptoms among women. Bacterial vaginosis leaves patients with undesirable vaginal discharge, malodor, and discomfort. Currently, the diagnosis of bacterial vaginosis is inaccurate and complex, leading to high rates of misdiagnosis. Inaccurate diagnoses are unsafe as bacterial vaginosis increases the risks of acquiring sexually transmitted infections as well as the likelihood of miscarriages. To date, the most commonly identified bacteria associated with bacterial vaginosis is Gardnerella vaginalis. We developed a method for the expression, purification, and detection of vaginolysin, the most well-characterized virulence factor of G. vaginalis. Elevated levels of G. vaginalis have been shown to lead to a toxic vaginal environment, facilitating bacterial vaginosis. We have developed an enzyme-linked immunosorbent assay for the detection of vaginolysin, which was translated to a lateral flow assay for use in a rapid, straightforward, cost-effective paper-based diagnostic test for vaginolysin that does not require the use of instrumentation. In conjunction, we have employed a commercially available smartphone microscopy kit to visualize clue cells without the need for equipment or electricity. The combination of these methodologies allows for an accurate and easy approach to diagnose bacterial vaginosis with minimal resources for use in any setting.
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Vaginose Bacteriana , Feminino , Gardnerella vaginalis/metabolismo , Humanos , Testes Imediatos , Smartphone , Vagina/microbiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/microbiologiaRESUMO
Improved techniques were applied to formulate drugs into dimensional nanostructures, doped "nanovesicles". These nanovesicles are solely composed of self-assembled amphiphilic antiviral agents used for the treatment of viral infections caused by flaviviruses, such as Zika virus. Studies were done to evaluate the effectiveness of the syntheses, formation, and performance under different experimental conditions, and behavior of the drug nanovesicles in vitro and in vivo. These studies demonstrated that assembling the hydrophobic antiviral drug molecules into nanodrugs is a successful technique for the delivery of the therapeutic agents, otherwise difficult to be supplied. Our studies confirmed that this nanodrug preserved and, in many cases, enhanced the embedded cellular activity of the parental free drug molecules, both in vitro and in vivo. This proposed formulation is highly important as it addresses the issue of insolubility and low bioavailabiity of a wide range of highly potent pharmaceutical drugs-not limited to a specific class of antiviral drugs-that are of high demand for the treatment of medical conditions and emerging pathogens.
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Acne is the most common skin condition in the United States and affects approximately 85% of people ages 12-24. As a multifactorial disease, the pathogenesis of acne involves overproduction of sebum, irregular shedding of the cutaneous cells, accretion of Cutibacterium acnes at the pilosebaceous unit, and inflammation. To date, conventional therapies for acne include topical retinoids, over-the-counter bactericidal agents, and systematic treatments, such as oral antibiotics and isotretinoin. However, the potential for significant side effects and risk of antibiotic resistance remain limitations in these therapies, in turn reducing patient compliance and adherence to acne treatment regimens. Therefore, the use of natural plant-derived treatments or phytotherapeutics as an alternative or adjuvant to conventional treatments is attractive to patients due to their safety and minimal risk for side effects. Cannabidiol (CBD) is a non-psychoactive phytocannabinoid of the Cannabis sativa (hemp) plant. The therapeutic use of CBD has been implicated in many diseases with an inflammatory aspect, including cancers, neurodegeneration, immunological disorders, and dermatological diseases. However, the use of CBD for acne treatment remains a novel window of opportunity. Herein, we summarize the available and relevant data, highlighting the potential use of CBD in acne for its anti-inflammatory properties. To that extent, CBD and other cannabis constituents such as cannabis seeds were found to reduce inflammation and expression of inflammatory cytokines including TNF-α and IL-1ß when evaluated in acne-like conditions. Treatment with these cannabis extracts was also found to be safe and well tolerated, further strengthening the prospect of CBD as an anti-inflammatory therapeutic for acne.
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The United States is in the midst of an opioid epidemic that is linked to a number of serious health issues, including an increase in cerebrovascular events, namely, stroke. Chronic prescription opioid use exacerbates the risk and severity of ischemic stroke, contributing to stroke as the fifth overall cause of death in the United States and costing the US health care system over $30 billion annually. Pathologically, opioids challenge the integrity of the blood-brain barrier (BBB), resulting in a dysregulation of tight junction (TJ) proteins that are crucial in maintaining barrier homeostasis. Despite this, treatment options for ischemic stroke are limited, and there are no pharmacological options to attenuate TJ damage, including in incidents that are linked to opioid use. Herein, we have generated carrier-free, pure "nanodrugs" or nanoparticles of naloxone and naltrexone with enhanced therapeutic properties compared to the original (parent) drugs. The generated nanoformulations of both opioid antagonists exhibited successful attenuation of morphine- or oxycodone-induced alterations of TJ protein expression and reduced oxidative stress to a greater extent than the parent drugs (non-nano). As a proof of concept, we then proceeded to evaluate the therapeutic effectiveness of the generated nanodrugs in an ischemic stroke model of mice exposed to morphine or oxycodone. Our results demonstrate that the opioid antagonist nanoformulations reduced stroke severity in mice. Overall, this research implements advances in nanotechnology-based repurposing of FDA-approved therapeutics, and the obtained results also suggest underlying pharmacological mechanisms of opioid antagonists, further supporting these opioid antagonists and their respective nanoformulations as potential therapeutic agents for ischemic stroke.
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AVC Isquêmico , Nanopartículas , Transtornos Relacionados ao Uso de Opioides , Acidente Vascular Cerebral , Analgésicos Opioides/uso terapêutico , Animais , AVC Isquêmico/tratamento farmacológico , Camundongos , Morfina/uso terapêutico , Naloxona , Naltrexona , Nanopartículas/uso terapêutico , Antagonistas de Entorpecentes/farmacologia , Antagonistas de Entorpecentes/uso terapêutico , Oxicodona , Acidente Vascular Cerebral/tratamento farmacológico , Proteínas de Junções ÍntimasRESUMO
OBJECTIVES: Evaluate the toxic effects of Aqueous Film-Forming Foams used by firefighters for Class B fire suppression in human-derived kidney cells (HEK-293). METHODS: Three widely used AFFFs were collected from fire departments and were added to HEK-293 cells in various concentrations. Seventy-two hours post-treatment, cellular proliferation and toxicity were examined using commercially available kits. RESULTS: All AFFFs evaluated induced cellular toxicity and significantly decreased cell proliferation, even when cells were treated with concentrations 10-fold lower than the working concentration used for fire suppression. CONCLUSIONS: Despite the reduced usage of PFAS-containing AFFFs in the firefighter work environment, the evaluated AFFFs demonstrated significantly altered cellular proliferation, while also inducing toxicity, indicating the presence of toxic compounds. Both stronger implementation of PFAS-containing AFFFs restrictions and robust evaluation of fluorine-free and next-generation AFFFs are warranted.
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Fluorocarbonos , Poluentes Químicos da Água , Aerossóis , Proliferação de Células , Células HEK293 , Humanos , ÁguaRESUMO
Pancreatic islet cells, and in particular insulin-producing beta cells, are centrally involved in the pathogenesis of diabetes mellitus. These cells are of paramount importance for the endocrine control of glycemia and glucose metabolism. In Type 1 Diabetes, islet beta cells are lost due to an autoimmune attack. In Type 2 Diabetes, beta cells become dysfunctional and insufficient to counterbalance insulin resistance in peripheral tissues. Therapeutic agents have been developed to support the function of islet cells, as well as to inhibit deleterious immune responses and inflammation. Most of these agents have undesired effects due to systemic administration and off-target effects. Typically, only a small fraction of therapeutic agent reaches the desired niche in the pancreas. Because islets and their beta cells are scattered throughout the pancreas, access to the niche is limited. Targeted delivery to pancreatic islets could dramatically improve the therapeutic effect, lower the dose requirements, and lower the side effects of agents administered systemically. Targeted delivery is especially relevant for those therapeutics for which the manufacturing is difficult and costly, such as cells, exosomes, and microvesicles. Along with therapeutic agents, imaging reagents intended to quantify the beta cell mass could benefit from targeted delivery. Several methods have been developed to improve the delivery of agents to pancreatic islets. Intra-arterial administration in the pancreatic artery is a promising surgical approach, but it has inherent risks. Targeted delivery strategies have been developed based on ligands for cell surface molecules specific to islet cells or inflamed vascular endothelial cells. Delivery methods range from nanocarriers and vectors to deliver pharmacological agents to viral and non-viral vectors for the delivery of genetic constructs. Several strategies demonstrated enhanced therapeutic effects in diabetes with lower amounts of therapeutic agents and lower off-target side effects. Microvesicles, exosomes, polymer-based vectors, and nanocarriers are gaining popularity for targeted delivery. Notably, liposomes, lipid-assisted nanocarriers, and cationic polymers can be bioengineered to be immune-evasive, and their advantages to transport cargos into target cells make them appealing for pancreatic islet-targeted delivery. Viral vectors have become prominent tools for targeted gene delivery. In this review, we discuss the latest strategies for targeted delivery of therapeutic agents and imaging reagents to pancreatic islet cells.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismoRESUMO
In recent years, the number of product recalls and contamination incidents involving pathogenic bacteria has significantly increased, and the ensuing infections continue to be an ongoing problem for public health and agriculture. Due to the widespread impact of these pathogens, there is a critical need for rapid, on-site assays that can provide rapid results. In this work, we demonstrate the development of a rapid and simple test based on the combination of reverse transcription with recombinase polymerase amplification followed by lateral flow strip detection of viable Escherichia coli O157:H7 cells by detecting the RNA of the pathogen. The optimized method can be performed for approximately 2 h with a detection limit of 10 CFU/mL of E. coli O157:H7 in buffer, spinach, and ground beef samples. Our assay is sensitive, detecting only E. coli O157:H7 and not nonpathogenic E. coli or other similar pathogens. This strategy was able to distinguish viable from nonviable bacteria and more significantly was able to detect viable but nonculturable bacteria, which is a major issue when using culture-based methods for monitoring pathogenic bacteria. An important advantage of this test is that it can provide timely identification and removal of contaminated consumables prior to distribution without an extensive sample preparation.