RESUMO
The replication organelle of hepatitis C virus (HCV), called membranous web, is derived from the endoplasmic reticulum (ER) and mainly comprises double membrane vesicles (DMVs) that concentrate the viral replication complexes. It also tightly associates with lipid droplets (LDs), which are essential for virion morphogenesis. In particular acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), a rate-limiting enzyme in triglyceride synthesis, promotes early steps of virus assembly. The close proximity between ER membranes, DMVs and LDs therefore permits the efficient coordination of the HCV replication cycle. Here, we demonstrate that exaggerated LD accumulation due to the excessive expression of the DGAT1 isozyme, DGAT2, dramatically impairs the formation of the HCV membranous web. This effect depended on the enzymatic activity and ER association of DGAT2, whereas the mere LD accumulation was not sufficient to hamper HCV RNA replication. Our lipidomics data indicate that both HCV infection and DGAT2 overexpression induced membrane lipid biogenesis and markedly increased phospholipids with long chain polyunsaturated fatty acids, suggesting a dual use of these lipids and their possible competition for LD and DMV biogenesis. On the other hand, overexpression of DGAT2 depleted specific phospholipids, particularly oleyl fatty acyl chain-containing phosphatidylcholines, which, in contrast, are increased in HCV-infected cells and likely essential for viral infection. In conclusion, our results indicate that lipid exchanges occurring during LD biogenesis regulate the composition of intracellular membranes and thereby affect the formation of the HCV replication organelle. The potent antiviral effect observed in our DGAT2 overexpression system unveils lipid flux that may be relevant in the context of steatohepatitis, a hallmark of HCV infection, but also in physiological conditions, locally in specific subdomains of the ER membrane. Thus, LD formation mediated by DGAT1 and DGAT2 might participate in the spatial compartmentalization of HCV replication and assembly factories within the membranous web.
Assuntos
Diacilglicerol O-Aciltransferase , Retículo Endoplasmático , Hepacivirus , Triglicerídeos , Replicação Viral , Diacilglicerol O-Aciltransferase/metabolismo , Diacilglicerol O-Aciltransferase/genética , Humanos , Hepacivirus/fisiologia , Replicação Viral/fisiologia , Triglicerídeos/metabolismo , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/virologia , Hepatite C/metabolismo , Hepatite C/virologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/virologiaRESUMO
Liver-generated plasma Apolipoprotein E (ApoE)-containing lipoproteins (LPs) (ApoE-LPs) play central roles in lipid transport and metabolism. Perturbations of ApoE can result in several metabolic disorders and ApoE genotypes have been associated with multiple diseases. ApoE is synthesized at the endoplasmic reticulum and transported to the Golgi apparatus for LP assembly; however, the ApoE-LPs transport pathway from there to the plasma membrane is largely unknown. Here, we established an integrative imaging approach based on a fully functional fluorescently tagged ApoE. We found that newly synthesized ApoE-LPs accumulate in CD63-positive endosomes of hepatocytes. In addition, we observed the co-egress of ApoE-LPs and CD63-positive intraluminal vesicles (ILVs), which are precursors of extracellular vesicles (EVs), along the late endosomal trafficking route in a microtubule-dependent manner. A fraction of ApoE-LPs associated with CD63-positive EVs appears to be co-transmitted from cell to cell. Given the important role of ApoE in viral infections, we employed as well-studied model the hepatitis C virus (HCV) and found that the viral replicase component nonstructural protein 5A (NS5A) is enriched in ApoE-containing ILVs. Interaction between NS5A and ApoE is required for the efficient release of ILVs containing HCV RNA. These vesicles are transported along the endosomal ApoE egress pathway. Taken together, our data argue for endosomal egress and transmission of hepatic ApoE-LPs, a pathway that is hijacked by HCV. Given the more general role of EV-mediated cell-to-cell communication, these insights provide new starting points for research into the pathophysiology of ApoE-related metabolic and infection-related disorders.
Assuntos
Hepacivirus , Hepatite C , Humanos , Hepacivirus/fisiologia , Lipopolissacarídeos/metabolismo , Montagem de Vírus/fisiologia , Endossomos/metabolismo , Apolipoproteínas E/metabolismoRESUMO
BACKGROUND: Effective strategies are needed to curtail overuse that may lead to harm. OBJECTIVE: To evaluate the effects of clinician decision support redirecting attention to harms and engaging social and reputational concerns on overuse in older primary care patients. DESIGN: 18-month, single-blind, pragmatic, cluster randomized trial, constrained randomization. (ClinicalTrials.gov: NCT04289753). SETTING: 60 primary care internal medicine, family medicine and geriatrics practices within a health system from 1 September 2020 to 28 February 2022. PARTICIPANTS: 371 primary care clinicians and their older adult patients from participating practices. INTERVENTION: Behavioral science-informed, point-of-care, clinical decision support tools plus brief case-based education addressing the 3 primary clinical outcomes (187 clinicians from 30 clinics) were compared with brief case-based education alone (187 clinicians from 30 clinics). Decision support was designed to increase salience of potential harms, convey social norms, and promote accountability. MEASUREMENTS: Prostate-specific antigen (PSA) testing in men aged 76 years and older without previous prostate cancer, urine testing for nonspecific reasons in women aged 65 years and older, and overtreatment of diabetes with hypoglycemic agents in patients aged 75 years and older and hemoglobin A1c (HbA1c) less than 7%. RESULTS: At randomization, mean clinic annual PSA testing, unspecified urine testing, and diabetes overtreatment rates were 24.9, 23.9, and 16.8 per 100 patients, respectively. After 18 months of intervention, the intervention group had lower adjusted difference-in-differences in annual rates of PSA testing (-8.7 [95% CI, -10.2 to -7.1]), unspecified urine testing (-5.5 [CI, -7.0 to -3.6]), and diabetes overtreatment (-1.4 [CI, -2.9 to -0.03]) compared with education only. Safety measures did not show increased emergency care related to urinary tract infections or hyperglycemia. An HbA1c greater than 9.0% was more common with the intervention among previously overtreated diabetes patients (adjusted difference-in-differences, 0.47 per 100 patients [95% CI, 0.04 to 1.20]). LIMITATION: A single health system limits generalizability; electronic health data limit ability to differentiate between overtesting and underdocumentation. CONCLUSION: Decision support designed to increase clinicians' attention to possible harms, social norms, and reputational concerns reduced unspecified testing compared with offering traditional case-based education alone. Small decreases in diabetes overtreatment may also result in higher rates of uncontrolled diabetes. PRIMARY FUNDING SOURCE: National Institute on Aging.
Assuntos
Diabetes Mellitus , Neoplasias da Próstata , Masculino , Humanos , Idoso , Antígeno Prostático Específico , Método Simples-Cego , HipoglicemiantesRESUMO
Sex differences are recognized in pulmonary hypertension. However, the progression of disease with regard to vascular lesion formation and circulating cytokines/chemokines is unknown. To determine whether vascular lesion formation, changes in hemodynamics, and alterations in circulating chemokines/cytokines differ between males and females, we used a progressive model of pulmonary arterial hypertension (PAH), Sugen/hypoxia, and analyzed cohorts of male and female rats at time points suggested to indicate worsening disease. Our analysis included echocardiography for hemodynamics, morphometry, immunofluoresecence, and chemokine/cytokine analysis of plasma at each time point in both sexes. We found that male rats had significantly increased Fulton index, compared with those for females at each time point, as well as increased medial artery thickening at 8 weeks of PAH. Furthermore, females exhibited fewer obliterative vascular lesions than males at our latest time point. Our data also show increased IL-4, granulocyte-macrophage colony-stimulating factor, IL-10, and macrophage interacting protein-1α that were not observed in females, whereas females were observed to have increased RANTES (whose name derives from Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted) and CXCL-10 that were not found in males. Males also have increased infiltrating macrophages in vascular lesions, compared with females. We found that development of progressive PAH in hemodynamics, morphology, and chemokine/cytokine circulation differs significantly between males and females. These data suggest a macrophage-driven pathology in males, whereas there may be T cell protection from vascular damage in females with PAH.
Assuntos
Quimiocinas , Citocinas , Modelos Animais de Doenças , Hemodinâmica , Animais , Masculino , Feminino , Citocinas/metabolismo , Citocinas/sangue , Quimiocinas/metabolismo , Quimiocinas/sangue , Caracteres Sexuais , Hipertensão Arterial Pulmonar/fisiopatologia , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/patologia , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Fatores SexuaisRESUMO
Lung endothelium resides at the interface between the circulation and the underlying tissue, where it senses biochemical and mechanical properties of both the blood as it flows through the vascular circuit and the vessel wall. The endothelium performs the bidirectional signaling between the blood and tissue compartments that is necessary to maintain homeostasis while physically separating both, facilitating a tightly regulated exchange of water, solutes, cells, and signals. Disruption in endothelial function contributes to vascular disease, which can manifest in discrete vascular locations along the artery-to-capillary-to-vein axis. Although our understanding of mechanisms that contribute to endothelial cell injury and repair in acute and chronic vascular disease have advanced, pathophysiological mechanisms that underlie site-specific vascular disease remain incompletely understood. In an effort to improve the translatability of mechanistic studies of the endothelium, the American Thoracic Society convened a workshop to optimize rigor, reproducibility, and translation of discovery to advance our understanding of endothelial cell function in health and disease.
Assuntos
Endotélio Vascular , Pulmão , Humanos , Pulmão/patologia , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Animais , Estados Unidos , Sociedades Médicas , Pneumopatias/patologia , Pneumopatias/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologiaRESUMO
Amyotrophic lateral sclerosis (ALS)-linked mutations in fused in sarcoma (FUS) lead to the formation of cytoplasmic aggregates in neurons. They are believed to play a critical role in the pathogenesis of FUS-associated ALS. Therefore, the clearance and degradation of cytoplasmic FUS aggregates in neurons may be considered a therapeutic strategy for ALS. However, the molecular pathogenic mechanisms behind FUS-associated ALS remain poorly understood. Here, we report GSK-3ß as a potential modulator of FUS-induced toxicity. We demonstrated that RNAi-mediated knockdown of Drosophila ortholog Shaggy in FUS-expressing flies suppresses defective phenotypes, including retinal degeneration, motor defects, motor neuron degeneration and mitochondrial dysfunction. Furthermore, we found that cytoplasmic FUS aggregates were significantly reduced by Shaggy knockdown. In addition, we found that the levels of FUS proteins were significantly reduced by co-overexpression of Slimb, a F-box protein, in FUS-expressing flies, indicating that Slimb is critical for the suppressive effect of Shaggy/GSK-3ß inhibition on FUS-induced toxicity in Drosophila. These findings revealed a novel mechanism of neuronal protective effect through SCFSlimb-mediated FUS degradation via GSK-3ß inhibition, and provided in vivo evidence of the potential for modulating FUS-induced ALS progression using GSK-3ß inhibitors.
Assuntos
Esclerose Lateral Amiotrófica , Proteínas de Drosophila , Síndromes Neurotóxicas , Esclerose Lateral Amiotrófica/metabolismo , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Mutação , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismoRESUMO
MAIN CONCLUSION: Genetic ablation of the female gametophyte provides direct evidence for the existence of interregional communication during Arabidopsis ovule development and the importance of the female gametophyte in nucellar-tip degeneration. The angiosperm ovule consists of three regions: the female gametophyte, the nucellus, and the integuments, all of which develop synchronously and coordinately. Previously, interregional communication enabling cooperative ovule development had been proposed; however, the evidence for these communications mostly relies on the analysis of mutant phenotypes. To provide direct evidence, we specifically ablated the Arabidopsis female gametophyte by expressing the diphtheria toxin fragment A (DTA) under the female gametophyte-specific DD13 promoter and analyzed its effects on the development of the nucellus and the integuments. We found that the female gametophyte is not required for integument development or for the orientation and curvature of the ovule body, but is necessary for nucellar-tip degeneration. The results presented here provide direct evidence for communication from the female gametophyte to the nucellus and demonstrate that Arabidopsis ovules require interregional communication for cooperative development.
Assuntos
Arabidopsis , Óvulo Vegetal , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente ModificadasRESUMO
Hepatitis C virus (HCV) is highly diverse and grouped into eight genotypes (gts). Infectious cell culture models are limited to a few subtypes and isolates, hampering the development of prophylactic vaccines. A consensus gt1b genome (termed GLT1) was generated from an HCV infected liver-transplanted patient. GLT1 replicated to an outstanding efficiency in Huh7 cells upon SEC14L2 expression, by use of replication enhancing mutations or with a previously developed inhibitor-based regimen. RNA replication levels almost reached JFH-1, but full-length genomes failed to produce detectable amounts of infectious virus. Long-term passaging led to the adaptation of a genome carrying 21 mutations and concomitant production of high levels of transmissible infectivity (GLT1cc). During the adaptation, GLT1 spread in the culture even in absence of detectable amounts of free virus, likely due to cell-to-cell transmission, which appeared to substantially contribute to spreading of other isolates as well. Mechanistically, genome replication and particle production efficiency were enhanced by adaptation, while cell entry competence of HCV pseudoparticles was not affected. Furthermore, GLT1cc retained the ability to replicate in human liver chimeric mice, which was critically dependent on a mutation in domain 3 of nonstructural protein NS5A. Over the course of infection, only one mutation in the surface glycoprotein E2 consistently reverted to wildtype, facilitating assembly in cell culture but potentially affecting CD81 interaction in vivo. Overall, GLT1cc is an efficient gt1b infectious cell culture model, paving the road to a rationale-based establishment of new infectious HCV isolates and represents an important novel tool for the development of prophylactic HCV vaccines.
Assuntos
Hepacivirus , Hepatite C , Animais , Técnicas de Cultura de Células , Genótipo , Humanos , Camundongos , Mutação , Proteínas não Estruturais Virais/metabolismo , Replicação ViralRESUMO
BACKGROUND: The prognostic role of changes in body fat in patients with idiopathic pulmonary fibrosis (IPF) remains underexplored. We investigated the association between changes in body fat during the first year post-diagnosis and outcomes in patients with IPF. METHODS: This single-center, retrospective study included IPF patients with chest CT scan and pulmonary function test (PFT) at diagnosis and a one-year follow-up between January 2010 and December 2020. The fat area (cm2, sum of subcutaneous and visceral fat) and muscle area (cm2) at the T12-L1 level were obtained from chest CT images using a fully automatic deep learning-based software. Changes in the body composition were dichotomized using thresholds dividing the lowest quartile and others, respectively (fat area: -52.3 cm2, muscle area: -7.4 cm2). Multivariable Cox regression analyses adjusted for PFT result and IPF extent on CT images and the log-rank test were performed to assess the association between the fat area change during the first year post-diagnosis and the composite outcome of death or lung transplantation. RESULTS: In total, 307 IPF patients (69.3 ± 8.1 years; 238 men) were included. During the first year post-diagnosis, fat area, muscle area, and body mass index (BMI) changed by -15.4 cm2, -1 cm2, and - 0.4 kg/m2, respectively. During a median follow-up of 47 months, 146 patients had the composite outcome (47.6%). In Cox regression analyses, a change in the fat area < -52.3 cm2 was associated with composite outcome incidence in models adjusted with baseline clinical variables (hazard ratio [HR], 1.566, P = .022; HR, 1.503, P = .036 in a model including gender, age, and physiology [GAP] index). This prognostic value was consistent when adjusted with one-year changes in clinical variables (HR, 1.495; P = .030). However, the change in BMI during the first year was not a significant prognostic factor (P = .941). Patients with a change in fat area exceeding this threshold experienced the composite outcome more frequently than their counterparts (58.4% vs. 43.9%; P = .007). CONCLUSION: A ≥ 52.3 cm2 decrease in fat area, automatically measured using deep learning technique, at T12-L1 in one year post-diagnosis was an independent poor prognostic factor in IPF patients.
Assuntos
Fibrose Pulmonar Idiopática , Masculino , Humanos , Estudos Retrospectivos , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Prognóstico , Tecido Adiposo , Composição Corporal , Tomografia Computadorizada por Raios XRESUMO
Class B G protein-coupled receptors (GPCRs) are notoriously difficult to target by small molecules because their large orthosteric peptide-binding pocket embedded deep within the transmembrane domain limits the identification and development of nonpeptide small molecule ligands. Using the parathyroid hormone type 1 receptor (PTHR) as a prototypic class B GPCR target, and a combination of molecular dynamics simulations and elastic network model-based methods, we demonstrate that PTHR druggability can be effectively addressed. Here we found a key mechanical site that modulates the collective dynamics of the receptor and used this ensemble of PTHR conformers to identify selective small molecules with strong negative allosteric and biased properties for PTHR signaling in cell and PTH actions in vivo. This study provides a computational pipeline to detect precise druggable sites and identify allosteric modulators of PTHR signaling that could be extended to GPCRs to expedite discoveries of small molecules as novel therapeutic candidates.
Assuntos
Receptor Tipo 1 de Hormônio Paratireóideo , Receptores Acoplados a Proteínas G , Ligantes , Simulação de Dinâmica Molecular , Transdução de SinaisRESUMO
OBJECTIVE: This study aimed to assess the recurrence risk factors in patients with early-stage endometrioid endometrial cancer (EC) who achieved a complete response (CR) through fertility-sparing hormonal treatment (FST). METHODS: We retrospectively analyzed patients who received FST for presumed stage IA and grade 1 endometrioid EC at two institutions. Medroxyprogesterone (MPA)- and levonorgestrel-releasing intrauterine devices (LNG-IUD) were used concurrently. Maintenance therapy involved maintaining the LNG-IUDs in situ for those who did not attempt to conceive immediately after achieving CR. Cox regression analysis was used to identify clinicopathological variables for recurrence-free survival (RFS) following CR. RESULTS: Among 178 patients with endometrioid EC who received FST, 142 (79.8 %) achieved CR. The median time to achieve CR and the median FST duration were 10 months (range 1-34) and 14 months (range 3-49), respectively. During the median follow-up period of 44 months (range 6-143), 59.9 % (85/142) of patients had recurrence, with a median RFS of 14 months (range 1-123) after CR. In multivariable analysis, age > 35-years (hazard ratio (HR) 1.892, 95 % confidence interval (CI) 1.224-2.923; P < 0.05) and pregnancy after the first CR (HR 0.203, 95 % CI 0.093-0.444; P < 0.05) were significantly associated with RFS. CONCLUSIONS: Older age and non-pregnancy status may be risk factors for recurrence after CR. Therefore, patients with these conditions should undergo stringent follow-up, including imaging and histological examinations, to detect recurrence after CR.
RESUMO
Aminopyrrolnitrin (APRN), a natural halogenated phenylpyrrole derivative (HPD), has strong antifungal and antiparasitic activities. Additionally, it showed 2.8-fold increased photostability compared to pyrrolnitrin, a commercially available HPD with antimicrobial activity. For microbial production of APRN, we first engineered anthranilate phosphoribosyltransferase encoded by trpD from Corynebacterium glutamicum, resulting in a TrpDA162D mutation that exhibits feedback-resistant against L-tryptophan and higher substrate affinity compared to wild-type TrpD. Plasmid-borne expression of trpDA162D in C. glutamicum TP851 strain with two copies of trpDA162D in the genome led to the production of 3.1 g/L L-tryptophan in flask culture. Subsequent step for L-tryptophan chlorination into 7-chloro-L-tryptophan was achieved by introducing diverse sources of genes encoding tryptophan 7-halogenase (PrnA or RebH) and flavin reductase (Fre, PrnF, or RebF). The combined expression of prnA from Serratia grimesii or Serratia plymuthica with flavin reductase gene from Escherichia coli, Pseudomonas fluorescens, or Lechevalieria aerocolonigenes yielded higher production of 7-chloro-L-tryptophan in comparison to other sets of two-component systems. In the next step, production of putative monodechloroaminopyrrolnitrin (MDAP) from 7-chloro-L-tryptophan was achieved through the expression of prnB encoding MDAP synthase from S. plymuthica or P. fluorescens. Finally, an artificial APRN biosynthetic pathway was constructed by simultaneously expressing genes coding for tryptophan 7-halogenase, flavin reductase, MDAP synthase, and MDAP halogenase (PrnC) from different microbial sources within the L-tryptophan-producing TP851 strain. As prnC from S. grimesii or S. plymuthica was introduced into the host strain, which carried plasmids expressing prnA from S. plymuthica, fre from E. coli, and prnB from S. plymuthica, APN3639 and APN3638 accumulated 29.5 mg/L and 28.1 mg/L of APRN in the culture broth. This study represents the first report on the fermentative APRN production by metabolically engineered C. glutamicum.
Assuntos
Corynebacterium glutamicum , Engenharia Metabólica , Corynebacterium glutamicum/metabolismo , Corynebacterium glutamicum/genética , Engenharia Metabólica/métodos , Pirrolnitrina/biossíntese , Pirrolnitrina/metabolismo , Fermentação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Triptofano/biossíntese , Triptofano/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , OxirredutasesRESUMO
BACKGROUND AND AIM: Although obesity is a known risk factor for colorectal neoplasms, the correlation between weight change and colorectal neoplasm is unclear. Thus, we aim to evaluate the association between weight change and advanced colorectal neoplasm (ACRN) recurrence during post-polypectomy surveillance colonoscopy. METHODS: This retrospective cohort study included 7473 participants diagnosed with colorectal neoplasms between 2003 and 2010 who subsequently underwent surveillance colonoscopies until 2020. We analyzed the association between the risk of metachronous ACRN and weight change, defining stable weight as a weight change of <3% and weight gain as a weight increase of ≥3% from baseline during the follow-up period. RESULTS: During a median 8.5 years of follow-up, 619 participants (8.3%) developed ACRN. Weight gain was reported as an independent risk factor for metachronous ACRN in a time-dependent Cox analysis. A weight gain of 3-6% and ≥6% had adjusted hazard ratios (AHRs) of 1.48 (95% confidence interval [CI]: 1.19-1.84) and 2.14 (95% CI: 1.71-2.69), respectively. Participants aged 30-49 and 50-75 years with weight gain of ≥6% showed AHRs of 2.88 (95% CI: 1.96-4.21) and 1.90 (95% CI: 1.43-2.51), respectively. In men and women, weight gain of ≥3% was significantly correlated with metachronous ACRN. CONCLUSIONS: Weight gain is associated with an increased risk of metachronous ACRN. Furthermore, weight gain is associated with the recurrence of ACRN in both men and women regardless of age.
Assuntos
Pólipos do Colo , Neoplasias Colorretais , Segunda Neoplasia Primária , Masculino , Humanos , Feminino , Pólipos do Colo/epidemiologia , Estudos Retrospectivos , Recidiva Local de Neoplasia/complicações , Colonoscopia/efeitos adversos , Fatores de Risco , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Aumento de Peso , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/etiologiaRESUMO
BACKGROUND AND AIM: Reliable bowel preparation assessment is important in colonoscopy. However, current scoring systems are limited by laborious and time-consuming tasks and interobserver variability. We aimed to develop an artificial intelligence (AI) model to assess bowel cleanliness and evaluate its clinical applicability. METHODS: A still image-driven AI model to assess the Boston Bowel Preparation Scale (BBPS) was developed and validated using 2361 colonoscopy images. For evaluating real-world applicability, the model was validated using 113 10-s colonoscopy video clips and 30 full colonoscopy videos to identify "adequate (BBPS 2-3)" or "inadequate (BBPS 0-1)" preparation. The model was tested with an external dataset of 29 colonoscopy videos. The clinical applicability of the model was evaluated using 225 consecutive colonoscopies. Inter-rater variability was analyzed between the AI model and endoscopists. RESULTS: The AI model achieved an accuracy of 94.0% and an area under the receiver operating characteristic curve of 0.939 with the still images. Model testing with an external dataset showed an accuracy of 95.3%, an area under the receiver operating characteristic curve of 0.976, and a sensitivity of 100% for the detection of inadequate preparations. The clinical applicability study showed an overall agreement rate of 85.3% between endoscopists and the AI model, with Fleiss' kappa of 0.686. The agreement rate was lower for the right colon compared with the transverse and left colon, with Fleiss' kappa of 0.563, 0.575, and 0.789, respectively. CONCLUSIONS: The AI model demonstrated accurate bowel preparation assessment and substantial agreement with endoscopists. Further refinement of the AI model is warranted for effective monitoring of qualified colonoscopy in large-scale screening programs.
Assuntos
Inteligência Artificial , Colonoscopia , Humanos , Colonoscopia/métodos , Feminino , Pessoa de Meia-Idade , Masculino , Catárticos/administração & dosagem , Idoso , Variações Dependentes do Observador , Adulto , Curva ROCRESUMO
We studied the hydroboration of the C70 fullerene using both B3LYP-D3(BJ)/6-311G(d,p) and M06-2X-D3/6-311G(d,p) levels of theory, incorporating the empirical dispersion interaction, and Fukui index calculations. Potential energy surfaces (PESs) and Gibbs free energy surfaces (GFESs) were calculated for the pathways from four BH3 adducts (located at the AB, CC, D, and E sites) on the C70 to eight products formed by the 1,2-addition of BH3 across the four [6,6]-ring fused bonds (AB, CC, DE, and EE) and across the two [5,6]-ring fused bonds (AA and DD). These pathways are two-step consecutive reactions. We denoted the positions on the fullerene cage as A through E, from the pole to the equator, based on the D5h symmetry of the C70 fullerene. In the first step reaction, the product ratios for the four adduct intermediates should be as the primary intermediate BH3(D), the secondary intermediate BH3(AB), the tertiary intermediate BH3(CC), and the minor intermediate BH3(E), based on the Fukui indices. In addition, in the second step reaction, transition states (TSs) from four adduct intermediates to eight product isomers, namely, BH2(A)H (B) to BH2(E)H (E), were obtained using the QST2 method. The calculated reaction coordinates showed exothermic reactions for all bonds except the EE bond. We also confirmed the transition states by frequency calculations and intrinsic reaction coordinate (IRC) analyses. The PESs and GFESs suggest spontaneous processes for the four isomers, of which the primary products are BH2(A)H (B) and its isomer BH2(B)H (A), the secondary product is BH2(C)H (C), and the tertiary product is BH2(D)H (D), all formed through adduct intermediates. Therefore, through the hydroboration reaction of C70, we could predict and design the site selectivity of C70 by controlling the energy barrier of the transition state in the second step of the reaction. This implies that we could selectively synthesize mainly BH2(B)H (A) isomers across the AB-[6,6]-ring fused bond and also design BH2(D)H(D) isomers across the DD-[5,6]-ring fused bond. Also, the calculations of formation rate constants can well simulate the experimental ratio of two C70H2 isomers by the hydrolysis of BH2(A)H(B), BH2(B)H(A), and BH2(C)H(C) products at room temperature.
RESUMO
BACKGROUND: Based on previous studies suggesting air pollution as a potential risk factor for Kawasaki Disease (KD), we examined the association of long-term exposure to childhood fine particulate matter (PM2.5) with the risk of KD. METHODS: We used National Health Insurance Service-National Sample Cohort data from 2002 to 2019, which included beneficiaries aged 0 years at enrollment and followed-up until the onset of KD or age 5 years. The onset of KD was defined as the first hospital visit record with a primary diagnostic code of M30.3, based on the 10th revision of the International Classification of Diseases, and with an intravenous immunoglobulin (IVIG) prescription. We assigned PM2.5 concentrations to 226 districts, based on mean annual predictions from a machine learning-based ensemble prediction model. We performed Cox proportional-hazards modeling with time-varying exposures and confounders. RESULTS: We identified 134,634 individuals aged five or less at enrollment and, of these, 1220 individuals who had a KD onset and an IVIG prescription during study period. The average annual concentration of PM2.5 exposed to the entire cohort was 28.2 µg/m³ (Standard Deviation 2.9). For each 5 µg/m³ increase in annual PM2.5 concentration, the hazard ratio of KD was 1.21 (95% CI 1.05-1.39). CONCLUSIONS: In this nationwide, population-based, cohort study, long-term childhood exposure to PM2.5 was associated with an increased incidence of KD in children. The study highlights plausible mechanisms for the association between PM2.5 and KD, but further studies are needed to confirm our findings.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Síndrome de Linfonodos Mucocutâneos , Criança , Humanos , Estudos de Coortes , Estudos Longitudinais , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Síndrome de Linfonodos Mucocutâneos/induzido quimicamente , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Imunoglobulinas Intravenosas , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Material Particulado/toxicidade , Material Particulado/análise , Poluição do Ar/efeitos adversosRESUMO
Plant vascular tissues, the conduits of water, nutrients, and small molecules, play important roles in plant growth and development. Vascular tissues have allowed plants to successfully adapt to various environmental conditions since they evolved 450 Mya. The majority of plant biomass, an important source of renewable energy, comes from the xylem of the vascular tissues. Efforts have been made to identify the underlying mechanisms of cell specification and patterning of plant vascular tissues and their proliferation. The formation of the plant vascular system is a complex process that integrates signaling and gene regulation at transcriptional and posttranscriptional levels. Recently, a wealth of molecular genetic studies and the advent of cell biology and genomic tools have enabled important progress toward understanding its underlying mechanisms. Here, we provide a comprehensive review of the cell and developmental processes of plant vascular tissue and resources recently available for studying them that will enable the discovery of new ways to develop sustainable energy using plant biomass.
Assuntos
Regulação da Expressão Gênica de Plantas , Plantas/embriologia , Transdução de Sinais , Xilema/crescimento & desenvolvimento , Diferenciação Celular , Floema/citologia , Floema/crescimento & desenvolvimento , Células Vegetais , Desenvolvimento Vegetal , Sementes/citologia , Sementes/crescimento & desenvolvimento , Xilema/citologiaRESUMO
Patients with familial hypokalemic periodic paralysis (HOKPP) experience episodes of reversible immobility and are at an increased risk of limited sunlight exposure, potentially leading to vitamin D deficiency. However, there is a lack of data on vitamin D levels in this population. We investigated serum vitamin D levels and their associated factors in children with HOKPP. This study included 170 genetically-confirmed children with HOKPP, aged 3-18 years, and 170 age-, sex-, and body mass index (BMI)-matched healthy controls from the Korean Channelopathy Study, a prospective controlled investigation. Anthropometric and clinical characteristics were recorded, and serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D, and intact parathyroid hormone (PTH) were analyzed. Vitamin D deficiency (< 20 ng/mL) was observed in 87.0% of the patients compared to 45.5% of the controls (P < 0.05) during the summer-fall season. During the winter-spring season, 91.7% of the patients and 73.4% of the controls were deficient (P < 0.05). A strong positive correlation was found between onset age of the first paralytic attack and vitamin D levels (r = 0.78, P < 0.01). Conversely, the frequency and duration of paralytic attacks were negatively correlated with vitamin D levels (r = -0.82 and r = -0.65, P < 0.01, respectively). Age, BMI, age at onset, frequency and duration of attacks, and PTH levels were independently associated with vitamin D levels (ß = -0.10, -0.12, 0.19, -0.27, -0.21, and -0.13, P < 0.05, respectively). CONCLUSIONS: Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics. We recommend routine screening for vitamin D levels in these patients to address this prevalent deficiency. Considering the high prevalence of vitamin D deficiency observed, further research on other diseases characterized by reversible immobility is warranted. WHAT IS KNOWN: ⢠A correlation between immobility and low serum vitamin D levels has been established. However, the vitamin D status of patients with familial hypokalemic periodic paralysis (HOKPP) who experience periods of reversible immobility remains unknown. WHAT IS NEW: ⢠Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics.
Assuntos
Paralisia Periódica Hipopotassêmica , Deficiência de Vitamina D , Criança , Humanos , Adolescente , Cálcio , Paralisia Periódica Hipopotassêmica/etiologia , Paralisia Periódica Hipopotassêmica/complicações , Estudos Prospectivos , Prevalência , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Fatores de Risco , Vitaminas , Hormônio Paratireóideo , Estações do AnoRESUMO
Plasticizers are necessary for the usability of various products, including food contact materials. Exposure to plasticizers is most commonly made through the oral route. Several plasticizers have been reported to have adverse effects on humans and the environment. Thus, the present study aimed to determine the long-term toxicity and carcinogenicity of a novel plasticizer called bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), which is an ecofriendly and biologically less harmful replacer. Groups of 50 male and 50 female Han Wistar rats were fed Eco-DEHCH at daily doses of 1,600, 5,000, or 16,000 ppm in their diet for at least 104 weeks. The rats were regularly monitored for mortality, clinical signs, body weight, food consumption, food efficiency, and perceivable mass. All animals were subjected to complete necropsy and histopathological examination. The results indicate that the rats well tolerated chronic exposure to Eco-DEHCH at highest daily doses of 16,000 ppm, with was equivalent to 805.1 mg/kg/day in males and 1060.6 mg/kg/day in females and did not show signs of toxicity or carcinogenicity. In conclusion, Eco-DEHCH could be a safe and promising alternative plasticizer.
Assuntos
Testes de Carcinogenicidade , Plastificantes , Ratos Wistar , Animais , Plastificantes/toxicidade , Masculino , Feminino , Ratos , Administração Oral , Ácidos Dicarboxílicos/toxicidade , Ácidos Dicarboxílicos/administração & dosagem , Relação Dose-Resposta a Droga , Cicloexanos/toxicidade , Cicloexanos/administração & dosagem , DietaRESUMO
L-tryptophan has been utilized as a feed additive in animal nutrition to improve growth performance, as well as a dietary supplement to alleviate various emotional symptoms in humans. Despite its benefits, concerns regarding its safety arose following the outbreak of eosinophilia-myalgia syndrome (EMS) among individuals who consumed L-tryptophan. The causative material of EMS was determined to be not L-tryptophan itself, but rather L-tryptophan impurities resulting from a specific manufacturing process. To investigate the effect of L-tryptophan and its impurities on humans who consume meat products derived from animals that were fed L-tryptophan and its impurities, an animal study involving broiler chickens was conducted. The animals in test groups were fed diet containing 0.065%-0.073% of L-tryptophan for 27 days. This study aimed to observe the occurrence of toxicological or EMS-related symptoms and analyze the residues of L-tryptophan impurities in meat products. The results indicated that there was no evidence of adverse effects associated with the test substance in the investigated parameters. Furthermore, most of the consumed EMS-causing L-tryptophan impurities did not remain in the meat of broiler chickens. Thus, this study demonstrated the safety of L-tryptophan and some of its impurities as a feed additive.