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Thrombospondin-1 (TSP1) is a matricellular protein associated with the regulation of cell migration through direct binding interactions with integrin proteins and by associating with other receptors known to regulate integrin function, including CD47 and CD36. We previously demonstrated that deletion of an epithelial TSP1 receptor CD47 attenuates epithelial wound repair following intestinal mucosal injury. However, the mechanisms by which TSP1 contributes to intestinal mucosal repair remains poorly understood. Our results show upregulated TSP1 expression in colonic mucosal wounds and impaired intestinal mucosal wound healing in vivo upon intestinal epithelial specific loss of TSP1 (VillinCre/+Thbs1f/f or Thbs1ΔIEC). We report that exposure to exogenous TSP1 enhanced migration of IECs in a CD47- and TGFß1-dependent manner, and that deficiency of TSP1 in primary murine colonic epithelial cells resulted in impaired wound healing. Mechanistically, TSP1 modulated epithelial actin cytoskeletal dynamics by suppression of RhoA activity, activation of Rac1, and changes in F-actin bundling. Overall, TSP1 was found to regulate intestinal mucosal wound healing via CD47 and TGFß1, coordinate integrin-containing cell-matrix adhesion dynamics and remodel the actin cytoskeleton in migrating epithelial cells to enhance cell motility and promote wound repair.
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Background: Hearing loss is a common sensorineural dysfunction with a high incidence in China. Although genetic factors are important causes of hearing loss, hearing-related gene detection has not been widely adopted in China. Objective: Establishing a rapid and efficient method to simultaneously detect hotspot hearing loss gene mutations. Methods: A reverse dot blot assay combined with a flow-through hybridization technique was developed for the simultaneous detection of 13 hotspot mutations of 4 hearing loss-related genes including GJB2, GJB3, SLC26A4, and the mitochondrial gene MT-RNR1. This method involved PCR amplification systems and a hybridization platform. Results: The technique can detect 13 hotspot mutations of 4 hearing loss-related genes. And a total of 213 blood samples were used to evaluate the availability of this method. Discussion: Our reverse dot blot assay was a simple, rapid, accurate, and cost-effective method to identify hotspot mutations of 4 hearing loss-related genes in a Chinese population.
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BACKGROUND & AIMS: CXADR-like membrane protein (CLMP) is structurally related to coxsackie and adenovirus receptor. Pathogenic variants in CLMP gene have been associated with congenital short bowel syndrome, implying a role for CLMP in intestinal development. However, the contribution of CLMP to regulating gut development and homeostasis is unknown. METHODS: In this study, we investigated CLMP function in the colonic epithelium using complementary in vivo and in vitro approaches, including mice with inducible intestinal epithelial cell (IEC)-specific deletion of CLMP (ClmpΔIEC), intestinal organoids, IECs with overexpression, or loss of CLMP and RNA sequencing data from individuals with colorectal cancer. RESULTS: Loss of CLMP enhanced IEC proliferation and, conversely, CLMP overexpression reduced proliferation. Xenograft experiments revealed increased tumor growth in mice implanted with CLMP-deficient colonic tumor cells, and poor engraftment was observed with CLMP-overexpressing cells. ClmpΔIEC mice showed exacerbated tumor burden in an azoxymethane and dextran sulfate sodium-induced colonic tumorigenesis model, and CLMP expression was reduced in human colorectal cancer samples. Mechanistic studies revealed that CLMP-dependent regulation of IEC proliferation is linked to signaling through mTOR-Akt-ß-catenin pathways. CONCLUSIONS: These results reveal novel insights into CLMP function in the colonic epithelium, highlighting an important role in regulating IEC proliferation, suggesting tumor suppressive function in colon cancer.
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Colitis , Neoplasias del Colon , Animales , Humanos , Ratones , Proliferación Celular , Colitis/inducido químicamente , Colitis/metabolismo , Neoplasias del Colon/patología , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus , Células Epiteliales/patología , Mucosa Intestinal/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismoRESUMEN
Selenite biotransformation by microorganisms is an effective detoxification and assimilation process. However, current knowledge of the molecular mechanisms of selenite reduction remains circumscribed. Here, the reduction of Se(IV) by a highly selenite-resistant Bacillus sp. SL (up to 50 mM) was systematically analyzed, and the molecular mechanisms of selenite reduction were investigated. Remarkably, 10 mM selenite was entirely transformed by the strain SL within 20 h, demonstrating a faster conversion rate compared to other microorganisms. Furthermore, glutathione (GSH) and exopolysaccharides (EPS) changes were also monitored during the process. Transcriptomic analysis revealed that the genes of ferredoxin-sulfite oxidoreductase (6.82) and sulfate adenylyltransferase (6.32) were significantly upregulated, indicating that the sulfur assimilation pathway is the primary reducing pathway involved in selenite reduction by strain SL. Moreover, key genes associated with NAD(P)/FAD-dependent oxidoreductases and thioredoxin were significantly upregulated. The reduction of Se(IV) was mediated by multiple pathways in strain SL. To our knowledge, this is the initial report to identify the involvement of sulfur assimilation pathway in selenite reduction for bacillus, which is rare in aerobic bacteria.
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Bacillus , Ácido Selenioso , Ácido Selenioso/metabolismo , Bacillus/genética , Bacillus/metabolismo , Transcriptoma/genética , Oxidación-Reducción , Oxidorreductasas/metabolismo , Selenito de Sodio/metabolismoRESUMEN
Testing for SARS-CoV-2 is crucial to tracking and controlling the pandemic. In particular, rapid testing in settings such as the emergency department (ED) could improve time to diagnosis and promote proper infection control measures. Early in the COVID-19 pandemic, we implemented the Abbott ID NOW COVID-19 method for screening symptomatic ED patients. However, due to concerns of suboptimal sensitivity, samples with a negative result were reflexed to the lab for confirmatory testing by the TaqPath COVID-19 Combo RT-PCR method. This study analyzed 6773 ID NOW results from April 2020 to September 2020 in the ED, of which 10% (n = 673) were positive and reported directly. The rest 90% (n = 6100) were negative and reflexed to RT-PCR. Among them, 3% (n = 175) turned positive on RT-PCR while 97% (n = 5925) of the results were consistently negative. The cycle threshold (Ct) values of the false-negative samples (n = 175) showed 90% (n = 158) of them with relatively low viral loads (Ct ≥ 30) with median Ct value at 35, while a number of samples (n = 17) had low Ct values (Ct < 30) and no clear explanation for false-negative results. Our study demonstrates that the Abbott ID NOW, despite it's sensitivity limitations, was capable of providing near real-time results for 10% of symptomatic patients presenting to the ED allowing for improved management and workflow. However, our study findings emphasize the need to reflex negative specimens to a higher sensitivity method when prevalence is high and false-negative results are intolerable.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiología , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Pandemias , Sensibilidad y Especificidad , Servicio de Urgencia en HospitalRESUMEN
Junctional adhesion molecule-A (JAM-A) is expressed in several cell types, including epithelial and endothelial cells, as well as some leukocytes. In intestinal epithelial cells (IEC), JAM-A localizes to cell junctions and plays a role in regulating barrier function. In vitro studies with model cell lines have shown that JAM-A contributes to IEC migration; however, in vivo studies investigating the role of JAM-A in cell migration-dependent processes such as mucosal wound repair have not been performed. In this study, we developed an inducible intestinal epithelial-specific JAM-A-knockdown mouse model (Jam-aERΔIEC). While acute induction of IEC-specific loss of JAM-A did not result in spontaneous colitis, such mice had significantly impaired mucosal healing after chemically induced colitis and after biopsy colonic wounding. In vitro primary cultures of JAM-A-deficient IEC demonstrated impaired migration in wound healing assays. Mechanistic studies revealed that JAM-A stabilizes formation of protein signaling complexes containing Rap1A/Talin/ß1 integrin at focal adhesions of migrating IECs. Loss of JAM-A in primary IEC led to decreased Rap1A activity and protein levels of Talin and ß1 integrin, and it led to a reduction in focal adhesion structures. These findings suggest that epithelial JAM-A plays a critical role in controlling mucosal repair in vivo through dynamic regulation of focal adhesions.
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Colitis , Molécula A de Adhesión de Unión , Animales , Colitis/inducido químicamente , Células Endoteliales/metabolismo , Integrina beta1/metabolismo , Ratones , TalinaRESUMEN
JAM-A is a tight-junction-associated protein that contributes to regulation of intestinal homeostasis. We report that JAM-A interacts with NF2 and LATS1, functioning as an initiator of the Hippo signaling pathway, well-known for regulation of proliferation. Consistent with these findings, we observed increased YAP activity in JAM-A-deficient intestinal epithelial cells (IEC). Furthermore, overexpression of a dimerization-deficient mutant, JAM-A-DL1, failed to initiate Hippo signaling, phenocopying JAM-A-deficient IEC, whereas overexpression of JAM-A-WT activated Hippo signaling and suppressed proliferation. Lastly, we identify EVI1, a transcription factor reported to promote cellular proliferation, as a contributor to the pro-proliferative phenotype in JAM-A-DL1 overexpressing IEC downstream of YAP. Collectively, our findings establish a new role for JAM-A as a cell-cell contact sensor, raising implications for understanding the contribution(s) of JAM-A to IEC proliferation in the mammalian epithelium.
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With the wide application of selenium nanoparticles (SeNPs) in pharmaceutical fields, the toxicity assessment is of great significance. In this study, zebrafish were selected as model organisms to compare the toxicity of SeNPs derived from biological and chemical methods. The results showed that the size of bio-SeNPs was about 5-fold bigger than chem-SeNPs. When exposed to SeNPs for 96 h, LC50 of bio-SeNPs and chem-SeNPs was 1.668 mg/L and 0.699 mg/L, respectively. Compared with the control, the results showed a significant increase in oxidative toxicity index (P < 0.05), such as glutathione (GSH), superoxide dismutase (SOD) of the liver, and gill in SeNPs-treated group. The neurotoxicity index, such as acetylcholinesterase (AchE) and Na+-K+-ATP enzyme activity, was significantly decreased both in the liver and gill (P < 0.05). It was found that the toxicity of bio-SeNPs to the liver and gill of zebrafish was lower than chem-SeNPs and the toxicity to the liver was higher than gill. In this study, the toxicity of chem-SeNPs and bio-SeNPs to the target organs of zebrafish were systematically evaluated, which provided the basis for the safe application of SeNPs synthesized by different pathways.
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Nanopartículas , Selenio , Acetilcolinesterasa/metabolismo , Animales , Branquias/metabolismo , Glutatión/metabolismo , Hígado/metabolismo , Nanopartículas/química , Nanopartículas/toxicidad , Estrés Oxidativo , Preparaciones Farmacéuticas/metabolismo , Selenio/metabolismo , Pez Cebra/metabolismoRESUMEN
Indole and phenol often coexist in the coking wastewater, while the effects of phenol on microbial communities of indole metabolism were less explored. In this study, the microbial interactions within activated sludge microbial communities stimulated by indole (group A) or by indole and phenol (group B) were systematically investigated in sequencing batch reactors (SBRs). The results showed that the removal of indole was increased by adding phenol. By using high-throughput sequencing technology, it was found that α-diversity was reduced in both groups. According to the relative abundance analysis, the indole-degrading genus Comamonas was the core genus in both groups (33.94% and 61.40%). But another indole-degrading genus Pseudomonas was only enriched in group A with 12.22% relative abundance. Meanwhile, common aromatic degrading genus Dyella and Thermomonas were enriched only in group B. It was found that the relative abundance of cytochrome P450 and styrene degradation enzymes were increased in group B by PICRUSt analysis. Based on the phylogenetic molecular ecological networks (pMENs), module hub OTU_1149 (Burkholderia) was only detected in group B, and the positive interactions between the key functional genus Burkholderia and other bacteria were increased. This study provides new insights into our understanding of indole metabolism communities stimulated by phenol, which would provide useful information for practical coking wastewater treatment.
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Microbiota , Aguas del Alcantarillado , Reactores Biológicos , Indoles/metabolismo , Indoles/farmacología , Fenol , Fenoles , Filogenia , Aguas del Alcantarillado/microbiología , Aguas ResidualesRESUMEN
The treatment and disposal of residual activated sludge is a worldwide problem and the research on its reuse is still only in the earliest stages. Selenite is a toxic pollutant, while selenium nanoparticles (SeNPs) are environmentally friendly and have promising application prospects. At present, the reduction mechanism of selenite under the complex system is still poorly understood. In order to explore the mechanism of SeNPs synthesis by activated sludge resource utilization, SeNPs were synthesized by activated sludge extracts of domestic sewage (DSeNPs) and coking sewage (CSeNPs), respectively. The synthesis process, zeta potential and morphology size of SeNPs were changed by pH value, extract concentration and extract composition. Under the same synthesis conditions, the morphologies of DSeNPs and CSeNPs were mainly spherical and pseudo-spherical, while CSeNPs also contained pseudo-rod shape particles. The sizes and crystal grains of CSeNPs were smaller than those of DSeNPs. Compared with DSeNPs, a specific protein (~35 kDa) was found on the surface of CSeNPs using SDS-PAGE. By analyzing the fluorescence images of the two SeNPs, it was found that the relative contents of proteins, α-d-glucopyranose polysaccharides, and ß-d-glucopyranose polysaccharides on their surfaces were obviously different (P < 0.05). The present study demonstrated that proteins, polysaccharides, humic-like and fulvic acid-like substances cooperated in the formation and stabilization of SeNPs. Furthermore, CSeNPs (bandgap: 1.68 eV) had more desirable photocatalytic performance than DSeNPs (bandgap: 1.84 eV). Under the light condition, CSeNPs could degrade Rhodamine B faster without adding hydrogen peroxide. This experiment provided a new insight into the resource utilization of activated sludge and a reference for the synthesis of nanometer selenium with excellent performance.
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Nanopartículas , Selenio , Polisacáridos , Ácido Selenioso , Aguas del AlcantarilladoRESUMEN
OBJECTIVES: Opioid overdose deaths in Massachusetts linked to illicitly-manufactured fentanyl have increased dramatically. In response, an urban safety-net hospital added urine fentanyl testing with reflex confirmation testing to its standard urine toxicology panel. The goals of this study were to describe fentanyl toxicology test results, identify the positive predictive value of presumptive fentanyl immunoassay, and describe co-substance use among those with unexpected fentanyl positive results. METHODS: We included urine toxicology tests from January through June 2016 analyzed at an urban safety-net hospital. We excluded tests from individuals prescribed or administered fentanyl within the preceding 72âhours. Positive fentanyl immunoassay tests underwent reflex chromatography confirmation testing. Samples that confirmed positive for acetyl fentanyl and/or fentanyl and/or norfentanyl were considered true positives. RESULTS: Of 11,873 urine samples, 10.4% of samples screened fentanyl positive and 8.8% were confirmed fentanyl positive. The positive predictive value of a positive urine fentanyl screen was 85.7%. Of 4398 unique patients, 13.2% had at least 1 test confirmed positive for nonprescription fentanyl. Patients with a confirmed fentanyl positive drug test were more likely to have positive urine drug test for barbiturates, benzodiazepines, cocaine, methadone, and opiates, and less likely to have oxycodone or buprenorphine. CONCLUSIONS: At an urban safety-net hospital, nonprescription fentanyl use was common and was associated with greater use of other substances favoring routine fentanyl testing. Although the positive predictive value of the screening test was high, confirmation testing detected substantial numbers of false positives, especially in older patients. Therefore, fentanyl confirmation testing should be used when results will change treatment approach and patient education.
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Fentanilo , Anciano , Humanos , Inmunoensayo , Massachusetts/epidemiología , Valor Predictivo de las Pruebas , PrevalenciaRESUMEN
Selenium nanoparticles (SeNPs) have attracted great interest as a potential antimicrobial agent. However, there is limited research on the antibacterial activity and possible mechanisms of biosynthesized SeNPs. In this study, spherical bio-SeNPs with an average size of 120 nm were synthesized by strain Providencia sp. DCX. The SeNPs were further applied to investigate the antibacterial properties of model bacteria, including Gram-positive (Staphylococcus aureus, Bacillus cereus and Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Vibrio parahemolyticus). The biosynthesized SeNPs demonstrated strong inhibition activity against the growth of these pathogens. When treated with 500 mg/L SeNPs, most of the tested bacteria were destructed within 12 h, among which the mortality rates of Gram-negative bacteria were much better. The leakage tests illustrated that there existed more proteins and polysaccharides outside the cells after reacted with bio-SeNPs. It was indicated that the leakages of proteins and polysaccharides were caused by permeability changes of membranes and the disruption of cell walls. And the change of reactive oxygen species (ROS) intensity indicated that oxidative damage may play the significant role in the antibacterial processes. The results showed that several bacteria could be effectively inhibited and destructed, suggesting the potential of using the biosynthesized SeNPs as antibacterial agents for bacterial infectious diseases.
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Antiinfecciosos , Nanopartículas del Metal , Nanopartículas , Selenio , Antibacterianos/farmacología , Nanopartículas del Metal/toxicidad , Nanopartículas/toxicidad , Providencia , Selenio/farmacologíaRESUMEN
Feasible and accurate predictors are urgently needed to evaluate the survival for patients with paraquat poisoning since the high mortality of paraquat poisoning always resulted in the loss of both life and money. Multiple predictors have been developed to predict prognosis of the patients with PQ poisoning, which however heavily depend on the time of admission to hospitals. Here we reported a feasible and accurate prognosis predictor for patients with paraquat poisoning that is independent of the time of admission to hospitals. Patients with paraquat poisoning were enrolled in this study according to the inclusion and exclusion criteria, which were grouped into survivors and non-survivors based on the 90-days follow-up investigation. The concentration of paraquat in serum and urine, and the baseline clinical parameters associated with the injuries of the liver, kidney, and lung were evaluated to predict the survival of these patients by using receiver operating characteristic curve (ROC) analysis, univariate and multivariate cox regression analyses. A total of 114 patients was included in this study with a survival rate of 54.4%. The median survival days of non-survivors were 6.0 (95%Cl: 4.0-7.8). A new predictor, namely paraquat concentration-associated multiorgan injury index (PCAMII), was established by integrating serum and urine paraquat concentration, serum creatinine, alanine aminotransferase, aspartate transaminase, total and direct bilirubin, at different weighting coefficients, with the accuracy of about 90%. The model to predict the survival probability by PCAMII was established with good fitness (R2 = 0.9325), providing the simulated survival rates comparable to the clinical data. PCAMII, which is independent of hospital admission time, is a feasible and accurate marker to predict the survival rate of patients with PQ poisoning.
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Paraquat , Humanos , Pronóstico , Curva ROC , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
In recent years, selenium nanoparticles (SeNPs) have been widely used in many fields such as nanotechnology, biomedicine and environmental remediation due to their good electrical conductivity, photothermal properties and anticancer properties. In this study, the cell-free supernatant, whole cell and the cell-free extracts of the strain Cupriavidus sp. SHE were used to synthesize SeNPs, and several methods were applied to analyze the crystal structure and surface functional groups of the nanoparticles. Finally, Pseudomonas sp. PI1 (Gâº) and Escherichia coli BL21 (Gâ») were selected to investigate the antibacterial properties of SeNPs. Cell-free supernatant, whole cell and cell-free extracts of the strain could synthesize SeNPs. As for the cell-free supernatant, selenite concentration of 5 mmol/L and pH=7 were favorable for the synthesis of SeNPs. TEM images show that the average size of nanospheres synthesized by the supernatant was 196 nm. XRD analysis indicates the hexagonal crystals structure of SeNPs. FTIR and SDS-PAGE confirmed the proteins bound to the surfaces of SeNPs. SeNPs synthesized by cell-free supernatant showed no antimicrobial activities against Pseudomonas sp. PI1 and Escherichia coli BL21 (DE3). These results suggest that proteins played an important role in biotransformation of SeNPs in an eco-friendly process, and SeNPs synthesized in this study were non-toxic and biologically compatible, which might be applied in other fields in the future.
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Cupriavidus , Nanopartículas , Selenio , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Cupriavidus/metabolismo , Ácido Selenioso/análisis , Selenio/química , Selenio/farmacologíaRESUMEN
The intestinal mucosa is lined by a single layer of epithelial cells that forms a tight barrier, separating luminal antigens and microbes from underlying tissue compartments. Mucosal damage results in a compromised epithelial barrier that can lead to excessive immune responses as observed in inflammatory bowel disease. Efficient wound repair is critical to reestablish the mucosal barrier and homeostasis. Intestinal epithelial cells (IEC) exclusively express the desmosomal cadherins, Desmoglein-2 and Desmocollin-2 (Dsc2) that contribute to mucosal homeostasis by strengthening intercellular adhesion between cells. Despite this important property, specific contributions of desmosomal cadherins to intestinal mucosal repair after injury remain poorly investigated in vivo. Here we show that mice with inducible conditional knockdown (KD) of Dsc2 in IEC (Villin-CreERT2; Dsc2 fl/fl) exhibited impaired mucosal repair after biopsy-induced colonic wounding and recovery from dextran sulfate sodium-induced colitis. In vitro analyses using human intestinal cell lines after KD of Dsc2 revealed delayed epithelial cell migration and repair after scratch-wound healing assay that was associated with reduced cell-matrix traction forces, decreased levels of integrin ß1 and ß4, and altered activity of the small GTPase Rap1. Taken together, these results demonstrate that epithelial Dsc2 is a key contributor to intestinal mucosal wound healing in vivo.
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Movimiento Celular , Desmocolinas/metabolismo , Integrinas/metabolismo , Mucosa Intestinal/patología , Cicatrización de Heridas , Animales , Adhesión Celular , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Enterocitos/metabolismo , Células Epiteliales/metabolismo , Matriz Extracelular/metabolismo , Eliminación de Gen , Humanos , Inflamación/patología , Ratones Endogámicos C57BL , Proteínas de Unión al GTP rap1/metabolismoRESUMEN
CD47 is a ubiquitously expressed transmembrane glycoprotein that regulates inflammatory responses and tissue repair. Here, we show that normal mice treated with anti-CD47 antibodies, and Cd47-null mice have impaired intestinal mucosal wound healing. Furthermore, intestinal epithelial cell (IEC)-specific loss of CD47 does not induce spontaneous immune-mediated intestinal barrier disruption but results in defective mucosal repair after biopsy-induced colonic wounding or Dextran Sulfate Sodium (DSS)-induced mucosal damage. In vitro analyses using primary cultures of CD47-deficient murine colonic IEC or human colonoid-derived IEC treated with CD47-blocking antibodies demonstrate impaired epithelial cell migration in wound healing assays. Defective wound repair after CD47 loss is linked to decreased epithelial ß1 integrin and focal adhesion signaling, as well as reduced thrombospondin-1 and TGF-ß1. These results demonstrate a critical role for IEC-expressed CD47 in regulating mucosal repair and raise important considerations for possible alterations in wound healing secondary to therapeutic targeting of CD47.
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Antígeno CD47/metabolismo , Células Epiteliales/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/fisiopatología , Cicatrización de Heridas/fisiología , Animales , Antígeno CD47/genética , Colitis/inducido químicamente , Colitis/genética , Colitis/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Humanos , Mucosa Intestinal/patología , Intestinos/patología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/genética , Trombospondina 1/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Cicatrización de Heridas/genéticaRESUMEN
OBJECTIVE: To determine if bicarbonate values from venous blood gas (VBG) and plasma chemistry samples provided agreement in determining the bicarbonate criteria for the diagnosis and/or resolution of diabetic ketoacidosis (DKA). METHODS: A retrospective chart review of data from patients admitted to a tertiary care hospital with a diagnosis of DKA over a four year period was performed. Paired bicarbonate values from a VBG and chemistry panel, if drawn within 60â¯minutes of each other, were compared. RESULTS: At the time of diagnosis of DKA, 197 paired bicarbonate values were available for analysis with the mean difference between the two methods of testing of 2.5â¯mmol/L. 16 of the 197 (8%) paired values were discordant in meeting criteria for diagnosis of DKA. At the time of resolution of DKA, 83 paired bicarbonate samples were compared. The mean difference was 2.3â¯mmol/L. 20 of the 83 (24%) paired bicarbonate values showed discordance with regards to meeting the bicarbonate criteria for resolution of DKA. CONCLUSION: Discordance between bicarbonate results from different analysis methods may lead to different determinations as to whether or not a patient meets the biochemical definition for diagnosis and resolution of DKA.
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Junctional adhesion molecule-A (JAM-A), an epithelial tight junction protein, plays an important role in regulating intestinal permeability through association with a scaffold signaling complex containing ZO-2, Afadin, and the small GTPase Rap2. Under inflammatory conditions, we report that the cytoplasmic tail of JAM-A is tyrosine phosphorylated (p-Y280) in association with loss of barrier function. While barely detectable Y280 phosphorylation was observed in confluent monolayers of human intestinal epithelial cells under basal conditions, exposure to cytokines TNFα, IFNγ, IL-22, or IL-17A, resulted in compromised barrier function in parallel with increased p-Y280. Phosphorylation was Src kinase dependent, and we identified Yes-1 and PTPN13 as a major kinase and phosphatase for p-JAM-A Y280, respectively. Moreover, cytokines IL-22 or IL-17A induced increased activity of Yes-1. Furthermore, the Src kinase inhibitor PP2 rescued cytokine-induced epithelial barrier defects and inhibited phosphorylation of JAM-A Y280 in vitro. Phosphorylation of JAM-A Y280 and increased permeability correlated with reduced JAM-A association with active Rap2. Finally, we observed increased phosphorylation of Y280 in colonic epithelium of individuals with ulcerative colitis and in mice with experimentally induced colitis. These findings support a novel mechanism by which tyrosine phosphorylation of JAM-A Y280 regulates epithelial barrier function during inflammation.
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Células Epiteliales/metabolismo , Inflamación/patología , Intestinos/patología , Molécula A de Adhesión de Unión/metabolismo , Fosfotirosina/metabolismo , Secuencia de Aminoácidos , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Citocinas/farmacología , Sulfato de Dextran , Células HEK293 , Humanos , Intestinos/química , Ratones Endogámicos C57BL , Modelos Biológicos , Fosforilación/efectos de los fármacos , Proteína Tirosina Fosfatasa no Receptora Tipo 13/metabolismo , Proteínas Proto-Oncogénicas c-yes/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Proteínas de Unión al GTP rap/metabolismoRESUMEN
BACKGROUND: We evaluated the effect of hemolysis, icterus and lipemia on 3 acetaminophen assays: namely the Syva® EMIT®, the Microgenics DRI® assay, and the Roche assay on a Roche Cobas® c501 or an Integra 800 analyzer. METHODS: Discarded acetaminophen - free serum samples (blank pool) and patient serum with acetaminophen overdose were used to prepare samples. Three levels of acetaminophen (5, 10, and 30⯵g/ml) were evaluated for interference: hemolysis (H index range: 0-1000), icterus (I index range: 0-40), and lipemia (L index range: 0-1000). RESULTS: Measurements showed that the EMIT® assay was not significantly affected by hemolysis or icterus at all 3concentrations evaluated, but was negatively affected by lipemia at all three levels at 1000â¯mg/dl intralipids. The DRI® assay was similarly affected by hemolysis and icterus, but lipemia (at 1000â¯mg/dl intralipids) only affected the 5⯵g/ml level. The Roche acetaminophen assay was significantly affected by hemolysis at all three concentrations. It was significantly affected by icterus at 20â¯mg/dl bilirubin andâ¯>â¯5⯵g/ml and at icterus levels of 30 and 40â¯mg/dl bilirubin at 10 and 30⯵g/ml acetaminophen concentrations, respectively. However, the Roche assay was least affected by lipemia. CONCLUSION: Hemolysis and icterus had insignificant interference on the Syva EMIT® and the DRI® assays for the analysis of acetaminophen, but significant interference effect on the Roche assay. On the other hand lipemia interfered less markedly with the Roche assay. The effect of hemolysis, icterus and lipemia should always be considered. Cautions are warranted when interpreting results for the potential false positive results in the presence of hemolysis and icterus at the concentrations evaluated in this study.
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Acetaminofén/sangre , Hemólisis , Hiperlipidemias/sangre , Ictericia/sangre , Reacciones Falso Positivas , HumanosRESUMEN
OBJECTIVES: To investigate whether combined continuous venovenous hemofiltration and hemoperfusion among paraquat-poisoned patients would improve survival. DESIGN: Prospective, controlled interventional study over 4 years. SETTING: Single, tertiary, academic medical center. PATIENTS: We recruited patients admitted to Shanghai Tenth People's Hospital within 48 hours after paraquat ingestion. Exclusions were under 14 years old, ingestion of paraquat with other toxicants, pregnant, a history of chronic pulmonary disease, psychosis, hyperthyroidism, or diabetes with impaired liver or renal function. INTERVENTIONS: All patients were assigned to receive continuous venovenous hemofiltration with hemoperfusion therapy (continuous venovenous hemofiltration group) and to receive conventional therapy (conventional group). The study outcomes were death from any cause within 90 days after paraquat ingestion and the frequencies of hypoxia, acute kidney injury, or adverse events. MEASUREMENTS AND MAIN RESULTS: Of the 110 enrolled patients, 59 were assigned to continuous venovenous hemofiltration group and 51 to conventional group. The two groups had similar baseline demographics and clinical features. At 90 days after paraquat ingestion, 19 of 59 patients (32.2%) in the continuous venovenous hemofiltration group and 29 of 51 patients (56.9%) in the conventional group had died (hazard ratio, 0.43; 95% CI, 0.24-0.76; p = 0.004). In multivariable Cox proportional hazard models controlling for baseline characteristics, combined continuous venovenous hemofiltration and hemoperfusion was independently associated with reduced risk of death compared with conventional therapy (adjusted hazard ratio, 0.35; 95% CI, 0.19-0.64; p = 0.001). Patients in the continuous venovenous hemofiltration group, as compared to the conventional group, had a reduced occurrence rate of hypoxia (40.7% vs 72.5%; p = 0.001) and of acute kidney injury (59.3% vs 78.4%; p = 0.03). Hypophosphatemia and thrombocytopenia were more common in the continuous venovenous hemofiltration group (p < 0.05). CONCLUSIONS: In patients with paraquat poisoning, treatment with combined continuous venovenous hemofiltration and hemoperfusion significantly improved 90-day survival rates.