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Background Preoperative local-regional tumor staging of gastric cancer (GC) is critical for appropriate treatment planning. The comparative accuracy of multiparametric MRI (mpMRI) versus dual-energy CT (DECT) for staging of GC is not known. Purpose To compare the diagnostic accuracy of personalized mpMRI with that of DECT for local-regional T and N staging in patients with GC receiving curative surgical intervention. Materials and Methods Patients with GC who underwent gastric mpMRI and DECT before gastrectomy with lymphadenectomy were eligible for this single-center prospective noninferiority study between November 2021 and September 2022. mpMRI comprised T2-weighted imaging, multiorientational zoomed diffusion-weighted imaging, and extradimensional volumetric interpolated breath-hold examination dynamic contrast-enhanced imaging. Dual-phase DECT images were reconstructed at 40 keV and standard 120 kVp-like images. Using gastrectomy specimens as the reference standard, the diagnostic accuracy of mpMRI and DECT for T and N staging was compared by six radiologists in a pairwise blinded manner. Interreader agreement was assessed using the weighted κ and Kendall W statistics. The McNemar test was used for head-to-head accuracy comparisons between DECT and mpMRI. Results This study included 202 participants (mean age, 62 years ± 11 [SD]; 145 male). The interreader agreement of the six readers for T and N staging of GC was excellent for both mpMRI (κ = 0.89 and 0.85, respectively) and DECT (κ = 0.86 and 0.84, respectively). Regardless of reader experience, higher accuracy was achieved with mpMRI than with DECT for both T (61%-77% vs 50%-64%; all P < .05) and N (54%-68% vs 51%-58%; P = .497-.005) staging, specifically T1 (83% vs 65%) and T4a (78% vs 68%) tumors and N1 (41% vs 24%) and N3 (64% vs 45%) nodules (all P < .05). Conclusion Personalized mpMRI was superior in T staging and noninferior or superior in N staging compared with DECT for patients with GC. Clinical trial registration no. NCT05508126 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Méndez and Martín-Garre in this issue.
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Estadiamento de Neoplasias , Neoplasias Gástricas , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Tomografia Computadorizada por Raios X/métodos , Gastrectomia/métodos , Adulto , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética Multiparamétrica/métodosRESUMO
OBJECTIVES: To investigate whether the interplay of anti-galectin-3 antibodies (anti-Gal3 Abs) with neutrophils contributes to the development of lupus cutaneous vasculitis. METHODS: Enzyme-linked immunosorbent assay was used to determine the serum level of anti-Gal3 Abs in lupus patients. Flow cytometry, quantitative PCR and western blot were performed to investigate the expression of cell surface receptors, proinflammatory cytokines and signalling molecules in neutrophils stimulated by serum from lupus patients or healthy controls (HCs) or anti-Gal3 Ab, respectively. Immunofluorescence was performed to visualise the formation of neutrophil extracellular traps (NETs). Human umbilical vein endothelial cells were co-cultured with the supernatants from neutrophils stimulated by anti-Gal3 Ab, and cytokine production was measured at mRNA and protein levels. Immunohistochemistry was adopted to reveal the distribution of Gal3, cytokines and myeloperoxidase within lupus skin lesions. REULTS: Serum levels of anti-Gal3 Abs were negatively correlated with peripheral counts of neutrophils. Anti-Gal3 Abs positive sera from SLE patients accelerated neutrophil death, altered cell phenotype and promoted formation of NETs with the involvement of p38 MAPK pathway. Supernatants collected from neutrophils co-cultured with anti-Gal3 Ab provoked endothelial cells to produce cytokines such as IL-1, ICAM-1, SELE and particularly IL-6. Consistently, IL-6 was higher in SLE patients with anti-Gal3 Ab positive sera and enriched in the area of vascular inflammation together with enhanced expression of Gal3 protein and infiltration of neutrophils. CONCLUSIONS: Overall, these findings suggested that neutrophils were crucial mediators in anti-Gal3 Ab induced lupus cutaneous vasculitis.
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OBJECTIVE: The purpose of this study is to identify the presence of occult peritoneal metastasis (OPM) in patients with advanced gastric cancer (AGC) by using clinical characteristics and abdominopelvic computed tomography (CT) features. METHODS: This retrospective study included 66 patients with OPM and 111 patients without peritoneal metastasis (non-PM [NPM]) who underwent preoperative contrast-enhanced CT between January 2020 and December 2021. Occult PMs means PMs that are missed by CT but later diagnosed by laparoscopy or laparotomy. Patients with NPM means patients have neither PM nor other distant metastases, indicating there is no evidence of distant metastases in patients with AGC. Patients' clinical characteristics and CT features such as tumor marker, Borrmann IV, enhancement patterns, and pelvic ascites were observed by 2 experienced radiologists. Computed tomography features and clinical characteristics were combined to construct an indicator for identifying the presence of OPM in patients with AGC based on a logistic regression model. Receiver operating characteristic curves and the area under the receiver operating characteristic curve (AUC) were generated to assess the diagnostic performance of the combined indicator. RESULTS: Four independent predictors (Borrmann IV, pelvic ascites, carbohydrate antigen 125, and normalized arterial CT value) differed significantly between OPM and NPM and performed outstandingly in distinguishing patients with OPM from those without PM (AUC = 0.643-0.696). The combined indicator showed a higher AUC value than the independent risk factors (0.820 vs 0.643-0.696). CONCLUSIONS: The combined indicator based on abdominopelvic CT features and carbohydrate antigen 125 may assist clinicians in identifying the presence of CT OPMs in patients with AGC.
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BACKGROUND: The triglyceride-glucose (TyG) index is a new, simple, and inexpensive marker of insulin resistance that is becoming increasingly important as a promising predictor of diseases such as atherosclerosis. Atherosclerosis is the main cause of lower extremity arterial disease (LEAD). In this study, we investigated the relationship between TyG index values and LEAD risk in patients with diabetes. METHODS: Patients with diabetes hospitalized at the Endocrinology Department of our hospital from June 1, 2021, to May 31, 2022, were retrospectively included. Baseline data, biochemical indicators, and ankle-brachial index values were collected. Statistical methods were used to assess the relationship between TyG index values and the risk of LEAD. RESULTS: A total of 1,040 hospitalized patients with diabetes were included, they were divided into the LEAD group with 168 patients and the no LEAD group with 872 patients. TyG index values in the LEAD group were higher than those in the no LEAD group (9.94 ± 0.78 vs. 9.36 ± 0.70, P < 0.001). TyG index values were independently correlated with LEAD risk in patients with diabetes (odds ratio = 3.92, 95% confidence interval (CI): 2.92-5.26, P < 0.001) in multivariate logistic regression analysis after adjusting for different risk factors (all P < 0.05). The area under the receiver operating characteristic curve was 0.72 (95% CI: 0.68-0.76) when TyG index values were used to diagnose LEAD in patients with diabetes. When Youden's index reached the maximum value of 0.34, the optimal TyG index threshold for predicting the onset of diabetic LEAD was 9.56, sensitivity was 71.1%, and specificity was 63.0%. CONCLUSIONS: Increases in TyG index values were associated with the risk of LEAD in patients with diabetes and, thus, may be used as a predictor of LEAD in this patient population, especially in primary care institutions with relatively few resources.
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Aterosclerose , Diabetes Mellitus , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Extremidade Inferior , Fatores de Risco , Glucose , Glicemia , Biomarcadores , TriglicerídeosRESUMO
A new C22 polyacetylene, erysectol A (1), and seven isoprenylated pterocarpans, phaseollin (2), phaseollidin (3), cristacarpin (4), (3'R)-erythribyssin D/(3'S)-erythribyssin D (5a/5b) and dolichina A/dolichina B (6a/6b) were isolated from the twigs and leaves of Erythrina subumbrans. Their structures were determined based on their NMR spectral data. Except for 2-4, all the other compounds were isolated from this plant for the first time. Erysectol A was the first reported C22 polyacetylene from plants. Polyacetylene was isolated from Erythrina plants for the first time.
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Erythrina , Pterocarpanos , Pterocarpanos/química , Erythrina/químicaRESUMO
Whether photosynthesis has improved with increasing yield in major crops remains controversial. Research in this area has often neglected to account for differences in light intensity experienced by cultivars released in different years. Light intensity is expected to be positively associated with photosynthetic capacity and the resistance of the photosynthetic apparatus to high light but negatively associated with light-utilization efficiency under low light. Here, we analyzed the light environment, photosynthetic activity, and protein components of leaves of 26 winter wheat cultivars released during the past 60 years in China. Over time, light levels on flag leaves significantly decreased due to architectural changes, but photosynthetic rates under high or low light and the resistance of the photosynthetic apparatus to high light remained steady, contrary to expectations. We propose that the difference between the actual and expected trends is due to breeding. Specifically, breeding has optimized photosynthetic performance under high light rather than low light. Moreover, breeding selectivity altered the stoichiometry of several proteins related to dynamic photosynthesis, canopy light distribution, and photoprotection. These results indicate that breeding has significantly altered the photosynthetic mechanism in wheat and its response to the light environment. These changes likely have helped increase wheat yields.
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Melhoramento Vegetal , Triticum , Luz , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Triticum/metabolismoRESUMO
BACKGROUND: Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a severe cutaneous adverse reaction to drugs with considerable morbidity and mortality. Immunomodulators for SJS/TEN including systemic corticosteroids and intravenous immunoglobulin (IVIG) have been widely used in clinical practice. Emerging evidence suggested the therapeutic effects of tumor necrosis factor-α antagonists on SJS/TEN. OBJECTIVE: To compare the efficacy and safety of IVIG and systemic steroids in conjunction with or without etanercept, a tumor necrosis factor-α inhibitor, for patients with SJS/TEN. METHODS: We undertook a retrospective review of 41 patients with SJS/TEN admitted to our institution from 2015 to February 2021. A total of 25 patients with integrated data were involved in this study, of which 14 patients were treated with IVIG and corticosteroids and 11 were in addition given etanercept. The clinical characteristics, duration of hospitalization, exposure time to high-dose steroids, and the total amount of systemic steroids were analyzed. RESULTS: In comparison to conventional therapy, conjunction with etanercept reduced the duration of hospitalization (13.5 vs 19.0 days; P = .01), the exposure time of high-dose steroids (7.1 vs 14.9 days; P = .01), and the overall amount of systemic steroid (925 mg vs 1412.5 mg; P = .03) in patients with SJS/TEN. No pronounced adverse effects were observed within 6 months of follow-up after the treatment. CONCLUSION: The add-in of etanercept at the time of initiating conventional therapy could be a superior option to accelerate disease recovery and reduce the high dose and total amount of systemic steroids without pronounced adverse events in patients with SJS/TEN.
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Etanercepte , Síndrome de Stevens-Johnson , Corticosteroides/uso terapêutico , Etanercepte/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Estudos Retrospectivos , Esteroides/uso terapêutico , Síndrome de Stevens-Johnson/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral/uso terapêuticoRESUMO
OBJECTIVE: This study aimed to compare the computed tomography (CT) features of gastric and small bowel gastrointestinal stromal tumors (GISTs) and further identify the predictors for risk stratification of them, respectively. METHODS: According to the modified National Institutes of Health criteria, patients were classified into low-malignant potential group and high-malignant potential group. Two experienced radiologists reviewed the CT features including the difference of CT values between arterial phase and portal venous phase (PVPMAP) by consensus. The CT features of gastric and small bowel GISTs were compared, and the association of CT features with risk grades was analyzed, respectively. Determinant CT features were used to construct corresponding models. RESULTS: Univariate analysis showed that small bowel GISTs tended to present with irregular contour, mixed growth pattern, ill-defined margin, severe necrosis, ulceration, tumor vessels, heterogeneous enhancement, larger size, and marked enhancement compared with gastric GISTs. According to multivariate analysis, tumor size (P < 0.001; odds ratio [OR], 3.279), necrosis (P = 0.008; OR, 2.104) and PVPMAP (P = 0.045; OR, 0.958) were the independent influencing factors for risk stratification of gastric GISTs. In terms of small bowel GISTs, the independent predictors were tumor size (P < 0.001; OR, 3.797) and ulceration (P = 0.031; OR, 4.027). Receiver operating characteristic curve indicated that the CT models for risk stratification of gastric and small bowel GISTs both achieved the best predictive performance. CONCLUSIONS: Computed tomography features of gastric and small bowel GISTs are different. Furthermore, the qualitative and quantitative CT features of GISTs may be favorable for preoperative risk stratification.
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Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/patologia , Humanos , Necrose , Curva ROC , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/métodos , Estados UnidosRESUMO
Di-2-ethylhexyl phosphate (DEHP) and its main toxic metabolite mono-2-ethylhexyl phthalate (MEHP) are the typical endocrine disrupting chemicals (EDCs) and widely affect human health. Our previous research reported that synthetic nonionic dietary emulsifier polysorbate 80 (P80, E433) had the promotional effect on the oral absorption of DEHP in rats. The aim of this study was to explore its mechanism of promoting oral absorption, focusing on the mucus barrier and mucosal barrier of the small intestine. A small molecule fluorescent probe 5-aminofluorescein-MEHP (MEHP-AF) was used as a tracker of MEHP in vivo and in vitro. First of all, we verified that P80 promoted the bioavailability of MEHP-AF in the long-term and low-dose exposure of MEHP-AF with P80 as a result of increasing the intestinal absorption of MEHP-AF. Afterwards, experimental results from Western blot, qPCR, immunohistochemistry, and immunofluorescence showed that P80 decreased the expression of proteins (mucus protein mucin-2, tight junction proteins claudin-1 and occludin) related to mucus barrier and mucosal barrier in the intestine, changed the integrity of intestinal epithelial cell, and increased the permeability of intestinal epithelial mucosa. These results indicated that P80 promoted the oral absorption of MEHP-AF by altering the intestinal mucus barrier and mucosal barrier. These findings are of great importance for assessing the safety risks of some food emulsifiers and clarifying the absorption mechanism of chemical pollutants in food, especially for EDCs.
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Dietilexilftalato/análogos & derivados , Emulsificantes/toxicidade , Células Epiteliais/efeitos dos fármacos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Polissorbatos/toxicidade , Animais , Disponibilidade Biológica , Células CACO-2 , Claudina-1/metabolismo , Dietilexilftalato/farmacocinética , Dietilexilftalato/toxicidade , Células Epiteliais/metabolismo , Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Células HT29 , Humanos , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Mucina-2/metabolismo , Ocludina/metabolismo , Permeabilidade , Ratos Sprague-Dawley , Distribuição Tecidual , ToxicocinéticaRESUMO
OBJECTIVE: To investigate the profiles of anti-RPLP0, anti-galectin3 antibodies, interferon-α (IFN-α), interferon-λ1(IFN-λ1) and interleukin-17A/F(IL-17A/F) in the subtypes of cutaneous lupus erythematosus (CLE) including acute CLE (ACLE), subacute CLE (SCLE) and discoid lupus erythematosus (DLE). METHODS: Serum levels of autoantibodies and cytokines were determined by enzyme-linked immunoabsorbent assay (ELISA). Lupus lesions were evaluated by cutaneous lupus erythematosus disease area and severity index (CLASI). RESULTS: Serum anti-RPLP0, anti-galectin3 antibodies and IFN-λ1 were higher in systemic lupus erythematosus (SLE) patients with skin lesions than those without skin lesions, compared to healthy controls. IFN-α, IL-17A and IL-17F was elevated in all patients regardless of skin lesions. The two antibodies, IFN-α and IL-17A were positively correlated with the CLASI score in all patients with CLE. In addition, serum IL-17A was positively correlated to the CLASI score of ACLE, SCLE and DLE, while anti-RPLP0 and anti-galectin3 antibodies were only correlated to the score of SCLE and IL-17F to DLE. CONCLUSION: Serum anti-RPLP0, anti-galectin3 antibodies, IFN-α, IFN-λ1 and IL-17A/F are associated with the occurrence of lupus skin lesions regardless of the systemic complications, whereas the profiles of these inflammatory mediators vary with the subtypes of lupus skin lesions.
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Autoanticorpos/sangue , Interferons/sangue , Interleucina-17/sangue , Lúpus Eritematoso Cutâneo/sangue , Lúpus Eritematoso Cutâneo/imunologia , Adulto , Autoanticorpos/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Interferons/imunologia , Interleucina-17/imunologia , Lúpus Eritematoso Discoide/sangue , Lúpus Eritematoso Discoide/imunologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Índice de Gravidade de Doença , Pele/imunologia , Pele/metabolismoRESUMO
ABSTRACT: Chronic arsenism usually occurs after a long-term unawareness of arsenic exposure from environment, occupation, food, and water. We here reported 3 cases with diffused arsenic keratosis and skin cancers derived from long-term arsenic medication ingestion. In these cases, hyperkeratotic skin lesions were initially found on palms and soles, slowly progressed to every part of the skin and lasted maximally for over 30 years. Skin cancers were diagnosed and removed intermittently within decades, but with no malignancies in other organs. Oral retinoids combing with topical 5- fluorouracil and photodynamic treatment yielded a desirable outcome.
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Intoxicação por Arsênico/patologia , Doença Iatrogênica , Ceratodermia Palmar e Plantar/induzido quimicamente , Neoplasias Cutâneas/induzido quimicamente , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Bombay and para-Bombay phenotypes, which arise from gene mutations of α-1,2-fucosyltransferase FUT1, are very rare in Chinese population. A para-Bombay phenotype Chinese individual with two novel FUT1 mutations was reported here. STUDY DESIGN AND METHODS: The peripheral blood and saliva samples of the proband and her family members were collected after informed consent. ABO and H blood group phenotyping was performed by haemagglutination methods. ABO genotype was determined by PCR-SSP kit. A, B, and H antigens in saliva were detected by a hemagglutination inhibition test. Fragments encompassing the full coding region of FUT1 and FUT2 genes were PCR amplified and sequenced. Allelic sequences were validated by cloning and sequencing individual colonies. RESULTS: The serologic reaction results of the proband revealed that A, B, and H antigen were absent on RBCs, but B and H antigen were presented in saliva, and the serum contains anti-H. The proband was assigned as B/O1 by ABO genotyping. Two new heterozygous mutations of FUT1 gene, c.508dupT and c.787A>C, were identified through direct sequencing of PCR-amplified products. TA cloning and sequencing confirmed that two novel mutations were on different alleles. FUT2 gene sequence of the proband is consistent with standard. The other family members of the proband showed normal phenotypes of ABO blood group and their genotypes are consistent with phenotypes. CONCLUSION: Two novel FUT1 alleles, with the previously not reported mutations c.508dupT and c.787C, respectively, are responsible for the para-Bombay phenotype detected in the sample from the proband.
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Sistema ABO de Grupos Sanguíneos/genética , Alelos , Fucosiltransferases/genética , Genótipo , China , Feminino , Humanos , Masculino , Galactosídeo 2-alfa-L-FucosiltransferaseRESUMO
OBJECTIVE. The objective of our study was to compare the performance of radiologicradiomic machine learning (ML) models and expert-level radiologists for differentiation of benign and malignant solid renal masses using contrast-enhanced CT examinations. MATERIALS AND METHODS. This retrospective study included a cohort of 254 renal cell carcinomas (RCCs) (190 clear cell RCCs [ccRCCs], 38 chromophobe RCCs [chrRCCs], and 26 papillary RCCs [pRCCs]), 26 fat-poor angioleiomyolipomas, and 10 oncocytomas with preoperative CT examinations. Lesions identified by four expert-level radiologists (> 3000 genitourinary CT and MRI studies) were manually segmented for radiologicradiomic analysis. Disease-specific support vector machine radiologic-radiomic ML models for classification of renal masses were trained and validated using a 10-fold cross-validation. Performance values for the expert-level radiologists and radiologic-radiomic ML models were compared using the McNemar test. RESULTS. The performance values for the four radiologists were as follows: sensitivity of 73.7-96.8% (median, 84.5%; variance, 122.7%) and specificity of 48.4-71.9% (median, 61.8%; variance, 161.6%) for differentiating ccRCCs from pRCCs and chrRCCs; sensitivity of 73.7-96.8% (median, 84.5%; variance, 122.7%) and specificity of 52.8-88.9% for differentiating ccRCCs from fat-poor angioleiomyolipomas and oncocytomas (median, 80.6%; variance, 269.1%); and sensitivity of 28.1-60.9% (median, 84.5%; variance, 122.7%) and specificity of 75.0-88.9% for differentiating pRCCs and chrRCCs from fat-poor angioleiomyolipomas and oncocytomas (median, 50.0%; variance, 191.1%). After a 10-fold cross-validation, the radiologic-radiomic ML model yielded the following performance values for differentiating ccRCCs from pRCCs and chrRCCs, ccRCCs from fat-poor angioleiomyolipomas and oncocytomas, and pRCCs and chrRCCs from fat-poor angioleiomyolipomas and oncocytomas: a sensitivity of 90.0%, 86.3%, and 73.4% and a specificity of 89.1%, 83.3%, and 91.7%, respectively. CONCLUSION. Expert-level radiologists had obviously large variances in performance for differentiating benign from malignant solid renal masses. Radiologic-radiomic ML can be a potential way to improve interreader concordance and performance.
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Competência Clínica , Nefropatias/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Modelos Teóricos , Radiologia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Ammonium (NH4 + ) represents a primary nitrogen source for many plants, its effective transport into and between tissues and further assimilation in cells determine greatly plant nitrogen use efficiency. However, biological components involved in NH4 + movement in woody plants are unclear. Here, we report kinetic evidence for cotton NH4 + uptake and molecular identification of certain NH4 + transporters (AMTs) from cotton (Gossypium hirustum). A substrate-influx assay using 15 N-isotope revealed that cotton possessed a high-affinity transport system with a Km of 58 µM for NH4 + . Sequence analysis showed that GhAMT1.1-1.3 encoded respectively a membrane protein containing 485, 509 or 499 amino acids. Heterologous functionality test demonstrated that GhAMT1.1-1.3 expression mediated NH4 + permeation across the plasma membrane (PM) of yeast and/or Arabidopsis qko-mutant cells, allowing a growth restoration of both mutants on NH4 + . Quantitative PCR measurement showed that GhAMT1.3 was expressed in roots and leaves and markedly up-regulated by N-starvation, repressed by NH4 + resupply and regulated diurnally and age-dependently, suggesting that GhAMT1.3 should be a N-responsive gene. Importantly, GhAMT1.3 expression in Arabidopsis improved plant growth on NH4 + and enhanced total nitrogen accumulation (â¼50% more), conforming with the observation of 2-fold more NH4 + absorption by GhAMT1.3-transformed qko plant roots during a 1-h root influx period. Together with its targeting to the PM and saturated transport kinetics with a Km of 72 µM for NH4 + , GhAMT1.3 is suggested to be a high-affinity NH4 + permease that may play a significant role in cotton NH4 + acquisition and utilization, adding a new member in the plant AMT family.
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Compostos de Amônio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Gossypium/genética , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Transporte Biológico , Proteínas de Transporte de Cátions/genética , Membrana Celular/metabolismo , Gossypium/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismoRESUMO
BACKGROUND: MicroRNAs (miRNAs) are critical modulators of various physiological and pathological processes, but their role in cardiac arrhythmias remains yet to be completely understood. Connexin43 (Cx43) is an important cardiac gap junction protein and a potential target of miR-206, and downregulation of Cx43 induces ventricular tachyarrhythmias. METHODS: We investigated the effects of miR-206 overexpression on the adult mouse heart and in cardiac arrhythmias. Luciferase activity assay was employed to validate Cx43 as a direct target of miR-206. Expression of Cx43 was measured in cardiac muscle cell line HL-1 securely expressing miR-206. An inducible miR-206 overexpression mouse model was established to evaluate the in vivo effect of miR-206 on Cx43 expression and cardiac rhythm. RESULTS: MiR-206 directly recognised 3'-untranslated region of Cx43 mRNA to inhibit its expression in HL-1 cells. Induction of miR-206 in the adult mouse heart suppressed Cx43 expression, particularly in the atria and ventricle. Importantly, miR-206 overexpression also induced abnormal heart-rate and PR interval, and shortened life-span in the experimental mice. CONCLUSIONS: In cardiomyocytes, miR-206 is a upstream regulator of Cx43, and its overexpression downregulates Cx43 to induce abnormal heart-rate and PR interval.
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Arritmias Cardíacas/genética , Conexina 43/genética , Regulação para Baixo , Regulação da Expressão Gênica , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/patologia , Western Blotting , Linhagem Celular , Conexina 43/biossíntese , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , MicroRNAs/biossíntese , Miócitos Cardíacos/patologiaRESUMO
Gold nanodendrites (Au NDs) exhibit extremely strong electromagnetic field located around multiple tip branches due to a plasmon coupling effect. In this work, a novel LSPR-enhanced ECL emission from CdTe nanocrystals (NCs) by Au NDs for the detection of nucleic acid is reported. This system is composed of a thin film of CdTe NCs on glassy carbon electrode (GCE) as anodic ECL emitter and Au NDs as plasmon enhancer. DNA tetrahedron embedded with a stem-loop hairpin structure on one edge was applied as a switch to regulate the distance between CdTe NCs and Au NDs. At original state, the hairpin structure was closed and DNA tetrahedron played in a relaxed state on CdTe NCs film. The ECL emission of CdTe NCs was quenched by proximal Au NDs due to Förster resonance energy transfer (FRET), which was defined as the "turn-off" mode. After the complementary hybridization with target DNA, the hairpin structure changed to a rodlike configuration, resulting in an increased distance between CdTe NCs and Au NDs, and a significant enhancement of ECL induced by LSPR of Au NDs, which was defined as a "turn-on" mode. Along with the asymmetric modification method, a controllable and versatile pathway for modifying nanomaterials, the ECL sensor performed well with great stability and repeatability for nucleic acid detection in the range from 1.0 to 500 fM. Considering the high sensitivity and selectivity in the serum sample assay, this proposed method indicates a great potential for bioassay application.
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The aim of the study was to develop an alternative capillary zone electrophoresis (CZE) for simultaneous determination of phillyrin (1), phillygenin (2), epipinoresinol-4-O-ß-glucoside (3), pinoresinol-4-O-ß-glucoside (4), lariciresinol (5), pinoresinol (6), isolariciresinol (7) and vladinol D (8) in Forsythia suspensa. The structural types of lignans 1-8 could be attributed to bisepoxylignans (1-4 and 6), monoepoxylignans (5 and 8) and cyclolignan (7). The major difficulties in the CZE separation of 1-8 could be summarization as the simultaneous presence of free lignans (1, 2 and 5-8) and lignan glucosides (3 and 4) and simultaneous occurrence of two pairs of isomers (3 and 4 as well as 5 and 7). Without the addition of ß-CD and methanol, the resolution of these analytes was quite poor. However, in this study, compounds 1-8 were excellently separated from each other within 15 min under optimized conditions with a borax running buffer (40 mM borax, pH 10.30) containing 2 mM ß-CD and 5% methanol (v/v) at the voltage of 20 kV, temperature of 35 °C and detection wavelength of 234 nm. Validation of the method included tests of linearity, precision, repeatability, stability and accuracy. In addition, the method offered inherent advantages such as lower analytical cost, no need of specific columns and use of small amounts of organic solvents and reagents. Finally, this green and economic CZE was successfully applied for the determination of these bioactive components 1-8 in F. suspensa fruits and its commercial extracts.
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Eletroforese Capilar , Forsythia/química , Lignanas/química , Lignanas/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , beta-Ciclodextrinas/química , Eletroforese Capilar/métodos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: To assess the efficacy of screening and confirmatory tests of primary aldosteronism (PA) in diagnosing aldosterone producing adenoma (APA). METHODS: Clinical data of 167 hypertensive patients were retrospectively reviewed,including 93 patients with APA and 74 patients with essential hypertension (EH). The area under curves (AUC) of receiver operating characteristic (ROC) curves were compared among the five indicators: supine plasma aldosterone concentration (PAC),absolute PAC values and PAC drop rates post saline infusion test (SIT) and captopril challenge test (CCT). RESULTS: APA patients had higher supine PAC,higher percentage of third degree hypertension,and lower serum potassium level than EH patients (P<0.05). Compared with EH patients,APA patients had lower PAC change rates,post posture change and SIT (P<0.05),but similar post CCT (P>0.05). The AUC of supine PAC reached 0.975. Higher AUC was found in absolute PAC values post SIT compared with PAC droop rates (0.984 vs. 0.680,P<0.001). Similar results were also found with CCT (0.949 vs. 0.538,P<0.001). A cut-off of supine aldosterone renin ratio (ARR) >30 and supine PAC>17.8 ng/dL had 96.8% sensitivity and 90.5% specificity. A cut-off of 14.59 ng/dL PAC post SIT had 90.2% sensitivity and 97.3% specificity. A cut-off of 19.11 ng/dL PAC post CCT had 88.8% sensitivity and 95.9% specificity. CONCLUSION: Screening tests using supine ARR>30 plus supine PAC>17.83 ng/dL are preferred with high sensitivity and specificity. The absolute values of PAC post SIT and CCT are recommended for confirming APA.
Assuntos
Adenoma/metabolismo , Aldosterona/biossíntese , Hiperaldosteronismo/diagnóstico , Humanos , Hipertensão/complicações , Renina , Estudos RetrospectivosRESUMO
We propose a laser rangefinder system based on the quadrature modem to achieve amplitude modulation, the method improves the accuracy of the phase measuring and simplifies the hardware design compared to the system with the secondary mixing methods, and to solve the range ambiguity caused by the measuring process, the ranging ambiguity resolving algorithm based on the over-determined equation is proposed, which avoids the searching of the optimal solution, finally the two K60 laser rangefinders and three proposed rangefinders were experimented on the national standard baseline with the precision of 0.18 mm. the measuring time of the proposed system is less than 1.8 s, the average measuring error of those three prototypes is less than 2 mm, and the standard deviation is less than 1 mm within the measuring range 0~60 m. The experimental results show that the proposed design system of the rangefinder has higher measurement accuracy and speed in comparison with the traditional ones, which indicates the high reliability of the proposed design system.
RESUMO
Here, a dual-wavelength ratiometric electrochemiluminescence (ECL) approach is reported based on resonance energy transfer (RET) from graphite-like carbon nitride nanosheet (g-C3N4 NS) to Ru(bpy)3(2+) for sensitive detection of microRNA (miRNA). In this approach, Au nanoparticles (Au NPs) functionalized g-C3N4 NS nanohybrid (Au-g-C3N4 NH) coated on glassy carbon electrode (GCE) could exhibit strong and stable ECL emissions with emission peak centered at 460 nm. The ECL emission at such wavelength matched well with the absorption peak of Ru(bpy)3(2+) as well as impeccably stimulating the emission of Ru(bpy)3(2+) at the wavelength of 620 nm, producing ECL-RET with high efficiency. Thus, based on the ECL signals quenching at 460 nm and increasing at 620 nm, a dual-wavelength ratiometric ECL-RET system was achieved. This system was then utilized for determination of target miRNA. With the attachment of thiol-modified molecular beacon on Au-g-C3N4 NH, target miRNA hybridized with the molecular beacon to form a DNA-RNA duplex. The obtained DNA-RNA duplex could be cleaved by duplex-specific nuclease to release target miRNA which would take part in the next cycle for further hybridization. Finally, the introducing of Ru(bpy)3(2+) was through the probe DNA-Ru(bpy)3(2+) complementary with the rest single-strand DNA on electrode. By measuring the ratio of ECL(460 nm)/ECL(620 nm), we could accurately quantify the concentration of miRNA-21 in a wide range from 1.0 fM to 1.0 nM. This work provides an important reference for the study of dual-wavelength ECL ratiometry and also exhibits potential capability in the detection of nucleic acids.