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Changes in ambient temperature immensely affect developmental programs in many species. Plants adapt to high ambient growth temperature in part by vegetative and reproductive developmental reprogramming, known as thermo-morphogenesis. Thermo-morphogenesis is accompanied by massive changes in the transcriptome upon temperature change. Here, we show that transcriptome changes induced by warm ambient temperature require VERNALIZATION INSENSITIVE 3-LIKE 1 (VIL1), a facultative component of the Polycomb repressive complex PRC2, in Arabidopsis. Warm growth temperature elicits genome-wide accumulation of H3K27me3 and VIL1 is necessary for the warm temperature-mediated accumulation of H3K27me3. Consistent with its role as a mediator of thermo-morphogenesis, loss of function of VIL1 results in hypo-responsiveness to warm ambient temperature. Our results show that VIL1 is a major chromatin regulator in responses to high ambient temperature.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Histonas/metabolismo , Proteínas do Grupo Polycomb , TemperaturaRESUMO
Glucosinolates (GSLs) are defensive secondary metabolites produced by Brassicaceae species in response to abiotic and biotic stresses. The biosynthesis of GSL compounds and the expression of GSL-related genes are highly modulated by endogenous signals (i.e. circadian clocks) and environmental cues, such as temperature, light, and pathogens. However, the detailed mechanism by which light signaling influences GSL metabolism remains poorly understood. In this study, we found that a light-signaling factor, ELONGATED HYPOCOTYL 5 (HY5), was involved in the regulation of GSL content under light conditions in Arabidopsis (Arabidopsis thaliana). In hy5-215 mutants, the transcript levels of GSL pathway genes were substantially upregulated compared with those in wild-type (WT) plants. The content of GSL compounds was also substantially increased in hy5-215 mutants, whereas 35S::HY5-GFP/hy5-215 transgenic lines exhibited comparable levels of GSL-related transcripts and GSL content to those in WT plants. HY5 physically interacts with HISTONE DEACETYLASE9 and binds to the proximal promoter region of MYB29 and IMD1 to suppress aliphatic GSL biosynthetic processes. These results demonstrate that HY5 suppresses GSL accumulation during the daytime, thus properly modulating GSL content daily in Arabidopsis plants.
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Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição de Zíper de Leucina Básica , Regulação da Expressão Gênica de Plantas , Glucosinolatos , Histona Desacetilases , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Glucosinolatos/biossíntese , Glucosinolatos/metabolismo , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Luz , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Mutação/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Ligação ProteicaRESUMO
Conventional avian genome editing is mediated by isolation, culture, and genome editing of primordial germ cells (PGCs); screening and propagating the genome-edited PGCs; and transplantation of the PGCs into recipient embryos. The PGC-mediated procedures, however, are technically difficult, and therefore, the conventional method has previously been utilized only in chickens. Here, we generated germline mosaic founder chicken and duck lines without the PGC-mediated procedures by injecting an adenovirus containing the CRISPR-Cas9 system into avian blastoderms. Genome-edited chicken and duck offspring produced from the founders carried different insertion or deletion mutations without mutations in the potential off-target sites. Our data demonstrate successful applications of the adenovirus-mediated method for production of genome-edited chicken and duck lines.
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Galinhas , Edição de Genes , Animais , Edição de Genes/métodos , Galinhas/genética , Patos/genética , Sistemas CRISPR-Cas , Adenoviridae/genética , Células GerminativasRESUMO
Advanced heterogeneous integration technologies are pivotal for next-generation electronics. Single-crystalline materials are one of the key building blocks for heterogeneous integration, although it is challenging to produce and integrate these materials. Remote epitaxy is recently introduced as a solution for growing single-crystalline thin films that can be exfoliated from host wafers and then transferred onto foreign platforms. This technology has quickly gained attention, as it can be applied to a wide variety of materials and can realize new functionalities and novel application platforms. Nevertheless, remote epitaxy is a delicate process, and thus, successful execution of remote epitaxy is often challenging. Here, we elucidate the mechanisms of remote epitaxy, summarize recent breakthroughs, and discuss the challenges and solutions in the remote epitaxy of various material systems. We also provide a vision for the future of remote epitaxy for studying fundamental materials science, as well as for functional applications.
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As sessile organisms, plants encounter dynamic and challenging environments daily, including abiotic/biotic stresses. The regulation of carbon and nitrogen allocations for the synthesis of plant proteins, carbohydrates, and lipids is fundamental for plant growth and adaption to its surroundings. Light, one of the essential environmental signals, exerts a substantial impact on plant metabolism and resource partitioning (i.e., starch). However, it is not fully understood how light signaling affects carbohydrate production and allocation in plant growth and development. An orphan gene unique to Arabidopsis thaliana, named QUA-QUINE STARCH (QQS) is involved in the metabolic processes for partitioning of carbon and nitrogen among proteins and carbohydrates, thus influencing leaf, seed composition, and plant defense in Arabidopsis. In this study, we show that PHYTOCHROME-INTERACTING bHLH TRANSCRIPTION FACTORS (PIFs), including PIF4, are required to suppress QQS during the period at dawn, thus preventing overconsumption of starch reserves. QQS expression is significantly de-repressed in pif4 and pifQ, while repressed by overexpression of PIF4, suggesting that PIF4 and its close homologs (PIF1, PIF3, and PIF5) act as negative regulators of QQS expression. In addition, we show that the evening complex, including ELF3 is required for active expression of QQS, thus playing a positive role in starch catabolism during night-time. Furthermore, QQS is epigenetically suppressed by DNA methylation machinery, whereas histone H3 K4 methyltransferases (e.g., ATX1, ATX2, and ATXR7) and H3 acetyltransferases (e.g., HAC1 and HAC5) are involved in the expression of QQS. This study demonstrates that PIF light signaling factors help plants utilize optimal amounts of starch during the night and prevent overconsumption of starch before its biosynthesis during the upcoming day.
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Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fitocromo/metabolismo , Amido/metabolismo , Carbono/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Nitrogênio/metabolismo , Regulação da Expressão Gênica de Plantas , Luz , Arseniato Redutases/genética , Arseniato Redutases/metabolismoRESUMO
Floral transition is accelerated by exposure to long-term cold like winter in plants, which is called as vernalization. Acceleration of floral transition by vernalization is observed in a diversity of biennial and perennial plants including Brassicaceae family plants. Scientific efforts to understand molecular mechanism underlying vernalization-mediated floral transition have been intensively focused in model plant Arabidopsis thaliana. To get a better understanding on floral transition by vernalization in radish (Raphanus sativus L.), we investigated transcriptomic changes taking place during vernalization in radish. Thousands of genes were differentially regulated along time course of vernalization compared to non-vernalization (NV) sample. Twelve major clusters of DEGs were identified based on distinctive expression profiles during vernalization. Radish FLC homologs were shown to exert an inhibition of floral transition when transformed into Arabidopsis plants. In addition, DNA region containing RY motifs located within a Raphanus sativus FLC homolog, RsFLC1 was found to be required for repression of RsFLC1 by vernalization. Transgenic plants harboring disrupted RY motifs were impaired in the enrichment of H3K27me3 on RsFLC1 chromatin, thus resulting in the delayed flowering in Arabidopsis. Taken together, we report transcriptomic profiles of radish during vernalization and demonstrate the requirement of RY motif for vernalization-mediated repression of RsFLC homologs in radish (Raphanus sativus L.).
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Arabidopsis , Brassicaceae , Raphanus , Raphanus/genética , Arabidopsis/genética , Vernalização , CromatinaRESUMO
BACKGROUND & AIMS: Ultrasound (US) is recommended for HCC surveillance in high-risk patients but has limited performance in detecting early-stage HCC. We aimed to compare the diagnostic performance of biannual US and annual non-contrast abbreviated magnetic resonance imaging (NC-AMRI) as HCC surveillance modalities in high-risk patients. METHODS: This prospective, multicenter cohort study enrolled participants with an estimated annual risk of HCC greater than 5% between October 2015 and April 2017. Participants underwent six rounds of HCC surveillance at 6-month intervals, with both US and NC-AMRI at rounds 1, 3, and 5, and only US at rounds 2, 4, and 6. The sensitivity, diagnostic yield (DY), and false referral rate (FRR) for HCC detection by US and NC-AMRI were compared. RESULTS: In total, 208 participants underwent 980 US and 516 NC-AMRI examinations during 30 months of follow-up. Among them, 34 HCCs were diagnosed in 31 participants, with 20 (64.5%) classified as very early-stage and 11 (35.5%) as early-stage HCC. The sensitivity of annual NC-AMRI (71.0%, 22/31) was marginally higher than that of biannual US (45.2%, 14/31; p = 0.077). NC-AMRI showed a significantly higher DY than US (4.26% vs. 1.43%, p <0.001), with a similar FRR (2.91% vs. 3.06%, p = 0.885). A simulation of alternating US and NC-AMRI at 6-month intervals yielded a sensitivity of 83.9% (26/31), significantly exceeding that of biannual US (p = 0.006). CONCLUSIONS: Annual NC-AMRI showed a marginally higher sensitivity than biannual US for HCC detection in high-risk patients. The DY of annual NC-AMRI was significantly higher than that of biannual US, without increasing the FRR. Thus, alternating US and NC-AMRI at 6-month intervals could be an optimal surveillance strategy for high-risk patients. IMPACT AND IMPLICATIONS: Current guidelines permit the use of magnetic resonance imaging (MRI) as a surveillance tool for hepatocellular carcinoma in patients in whom ultrasonography (US) is inadequate. However, the specific indications, imaging sequences, and intervals for MRI surveillance remain unclear. In our study, we found that annual non-contrast abbreviated MRI exhibited marginally higher sensitivity and significantly better diagnostic yield than biannual US in patients at high risk of hepatocellular carcinoma. Alternating US and non-contrast abbreviated MRI at 6-month intervals led to significantly improved sensitivity compared to biannual US, making it a potentially optimal surveillance strategy for high-risk patients. GOV IDENTIFIER: NCT02551250.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Imageamento por Ressonância Magnética , Ultrassonografia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Feminino , Masculino , Ultrassonografia/métodos , Ultrassonografia/estatística & dados numéricos , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Detecção Precoce de Câncer/métodos , Sensibilidade e EspecificidadeRESUMO
OBJECTIVES: We aimed to compare the early responder rates, defined as complete or partial responders, using response evaluation criteria in solid tumors (RECIST) 1.1, modified RECIST (mRECIST), and Choi criteria in advanced HCC patients treated with atezolizumab-bevacizumab (atezo-bev), and to correlate them with progression-free survival (PFS) and overall survival (OS). METHODS: This retrospective study included advanced HCC patients treated with ≥ 3 cycles of atezo-bev. Two reviewers assessed responses using RECIST 1.1, mRECIST, and Choi criteria at 1st follow-up imaging. Kaplan-Meier curves with log-rank tests evaluated and compared PFS and OS. Cox proportional hazard models identified survival outcome predictors. Kappa statistics assessed inter-reader agreement. RESULTS: We evaluated 77 patients (65 men; mean age, 62.8 ± 12.3 years). Choi's criteria revealed the highest early responders rate (53.2%), exceeding mRECIST (32.5-33.8%) and RECIST 1.1 (24.7-26.0%), with an excellent agreement in all criteria (κ, 0.85-0.95). Across criteria, a consistent number of patients progressed (23-26) and was associated with significantly poor OS (ps ≤ 0.049). Responders by any criteria showed longer PFS (ps ≤ 0.009), and 1-year OS (ps ≤ 0.01). Choi criteria linked to significantly better OS without landmark (p = 0.003), with 1-year OS rates at 76.9% for responders vs 38.1% for non-responders. Cox analysis identified responders by Choi criteria as a significant OS predictor. CONCLUSION: Choi criteria identified more early responders than RECIST 1.1 and mRECIST, significantly correlating with improved OS. Choi criteria could be considered as a formal response assessment criterion for the emerging atezo-bev systemic treatment. CLINICAL RELEVANCE STATEMENT: For atezo-bev treatment of advanced HCC, more comprehensive response criteria, such as Choi criteria, could be effective in identifying early responders and predicting survival outcomes along with RECIST 1.1 and mRECIST. KEY POINTS: Choi criteria identified a higher rate of early responders compared to mRECIST and RECIST1.1 following atezo-bev treatment. Responders by all criteria had longer PFS and 1-year OS, and only those by Choi criteria experienced longer OS without landmark time. Choi criteria, with RECIST 1.1 and mRECIST, is an effective response assessment tool for atezo-bev treatment.
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PURPOSE: Infectious spondylitis is caused by hematogenous seeding or adjacent soft tissue infection. No study has provided evidence that incubating biopsy specimens in blood culture bottles could enhance detection rates, nor has any study compared this method with conventional culture techniques. We aimed to assess the diagnostic yield of open microsurgical biopsies for infectious spondylitis and the efficacy of various culture media in the presence and absence of pre-biopsy antibiotic therapy. METHODS: This retrospective study, which was conducted at a university-affiliated teaching hospital in Korea, enrolled 165 adult patients with suspected infectious spondylitis between February 2014 and September 2020. The diagnostic yield of open biopsy was compared among three culture media, namely, blood culture bottles, swab culture using transport media, and tissue culture using plain tubes, while considering preoperative antibiotic exposure. RESULTS: Causative bacteria were identified in 84.2% of all cases. Blood culture bottles had the highest positivity rate (83.5%), followed by swab cultures (64.4%) and tissue cultures (44.9%). The differences in positivity rates were significant (P < 0.001). Preoperative antibiotic therapy reduced detection rates across all media, particularly in tissue cultures. CONCLUSIONS: We established the high diagnostic yield of open microsurgical biopsy using blood culture bottles, suggesting that pre-biopsy antibiotic therapy significantly affects bacterial detection, thereby underscoring the importance of culture medium selection in the diagnosis of infectious spondylitis.
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Hemocultura , Salas Cirúrgicas , Espondilite , Humanos , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Biópsia , Espondilite/diagnóstico , Espondilite/microbiologia , Hemocultura/métodos , Idoso , Adulto , Microcirurgia/métodos , Bactérias/isolamento & purificação , Bactérias/classificação , Meios de Cultura , República da Coreia , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Idoso de 80 Anos ou maisRESUMO
Methylglyoxal (MG) is a toxic by-product of the glycolysis pathway in most living organisms and was previously shown to inhibit seed germination. MG is detoxified by glyoxalase I and II family proteins in plants. MG is abundantly produced during early embryogenesis in Arabidopsis seeds. However, the mechanism that alleviates the toxic effect of MG in maturing seeds is poorly understood. In this study, by T-DNA mutant population screening, we found that mutations in a glyoxalase I gene (named GERMINATION-IMPAIRED GLYOXALASE 1, GIG1) led to significantly impaired germination compared with wild-type seeds. Transformation of full-length GIG1 cDNA under the constitutively active cauliflower mosaic virus 35S promoter in the gig1 background completely recovered the seed germination phenotype. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses revealed that GIG1 is uniquely expressed in seeds and is upregulated by abscisic acid (ABA) and downregulated by gibberellic acid (GA) during seed germination. An ABA signaling component, ABI3, directly activated GIG1 in maturing seeds. In addition, PHYTOCHROME INTERACTING FACTOR 1 (PIF1) also plays cooperatively with ABI3 in the regulation of GIG1 expression in the early stage of imbibed seeds. Furthermore, GIG1 expression is stably silenced by epigenetic repressors such as polycomb repressor complexes. Altogether, our results indicate that light and ABA signaling cooperate to enhance seed germination by the upregulation of GIG1 to detoxify MG in maturing seeds.
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Proteínas de Arabidopsis , Arabidopsis , Lactoilglutationa Liase , Fitocromo , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Fitocromo/metabolismo , Aldeído Pirúvico/metabolismo , Sementes/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Alkaline phosphatase (ALP) and interleukin-1beta (IL-1ß) are crucial salivary biomarkers for the diagnosis of periodontal disease that harms the periodontal tissue along with tooth loss. However, there has been no way of sensitive and portable detection of both biomarkers in saliva with multivariate signal readout. In this work, we design the multicolorimetric ALP and IL-1ß sensing platform based on geometrical transformation of silver nanoplate transducer. By utilizing enzymatic activity of ALP that dephosphorylates p-aminophenol phosphate (p-APP) to p-aminophenol (p-AP), localized surface plasmon resonance properties of silver nanoplate vary with ALP and show a distinct color change from blue to yellow based on a controlled seed transformation from triangular to hexagonal, rounded pentagonal, and spherical shape. The multicolor sensor shows an ALP detection range of 0-25 U/L with a limit of detection (LOD) of 0.0011 U/L, which is the lowest range of LOD demonstrated to date for state-of-the-art ALP sensor. Furthermore, we integrate the sensor with the conventional ELISA to detect IL-1ß for multicolor signaling and it exhibits a linear detection range of 0-250 pg/mL and an LOD of 0.066 pg/mL, which is 2 orders of magnitude lower than the monochromic conventional ELISA (LOD of 3.8 pg/mL). The ALP multicolor sensor shows high selectivity with a recovery of 100.9% in real human saliva proving its reliability and suitability for the readily accessible periodontal diagnosis with multivariate signal readout.
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Doenças Periodontais , Prata , Humanos , Reprodutibilidade dos Testes , Fosfatase Alcalina/análise , Doenças Periodontais/diagnóstico , Corantes , Biomarcadores , Limite de DetecçãoRESUMO
This study reports the performance and durability of a protonic ceramic fuel cells (PCFCs) in an ammonia fuel injection environment. The low ammonia decomposition rate in PCFCs with lower operating temperatures is improved relative to that of solid oxide fuel cells by treatment with a catalyst. By treating the anode of the PCFCs with a palladium (Pd) catalyst at 500 °C under ammonia fuel injection, the performance (peak power density of 340 mW cm-2 at 500 °C) is approximately two-fold higher than that of the bare sample not treated with Pd. Pd catalysts are deposited through an atomic layer deposition post-treatment process on the anode surface, in which nickel oxide (NiO) and BaZr0.2 Ce0.6 Y0.1 Yb0.1 O3-δ (BZCYYb) are mixed, and Pd can penetrate the anode surface and porous interior. Impedance analysis confirmed that Pd increased the current collection and significantly reduced the polarization resistance, particularly in the low-temperature region (≈500 °C), thereby improving the performance. Furthermore, stability tests showed that superior durability is achieved compared with that of the bare sample. Based on these results, the method presented herein is expected to represent a promising solution for securing high-performance and stable PCFCs based on ammonia injection.
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INTRODUCTION: En bloc kidney transplantation (EBKT) is a technique used to transplant pediatric kidneys to adult recipients, but can lead to certain complications seldom found in single-kidney transplantation. We report a case of renal artery embolization after EBKT due to intractable unilateral hydronephrosis and highlight the technical details and challenges of the procedure. CASE: An 18-year-old female with MELAS syndrome underwent EBKT from a 10-month-old male baby. Two months later, the patient developed unilateral hydronephrosis and recurrent urinary tract infections, which was intractable to conventional therapy. Therefore, we underwent embolization of the problematic transplanted left kidney. Owing to the complicated anatomy and multiple angulations, multiple microcatheters, wires and support catheters were needed to select the renal arteries. Repeated procedures were required due to remnant flow from small branches and accessory renal arteries that were not easily visualized by conventional angiography, which were eventually detected by adjunctive use of 3-dimensional rotational angiography. CONCLUSIONS: Selective renal artery embolization after EBKT is challenging due to the short renal artery length and multiple angulations, yet it can still be performed safely and effectively by use of meticulous catheter-wire interactions and adjunctive intraoperative imaging techniques to delineate the precise anatomy of the target arteries. CLINICAL IMPACT: Selective renal artery embolization, which is less invasive than nephrectomy, can be considered if the culprit kidney must inevitably be sacrificed in en bloc kidney transplantation.
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Plants have evolved many systems to sense their environment and to modify their growth and development accordingly. One example is vernalization, the process by which flowering is promoted as plants sense exposure to the cold temperatures of winter. A requirement for vernalization is an adaptive trait that helps prevent flowering before winter and permits flowering in the favorable conditions of spring. In Arabidopsis and cereals, vernalization results in the suppression of genes that repress flowering. We describe recent progress in understanding the molecular basis of this suppression. In Arabidopsis, vernalization involves the recruitment of chromatin-modifying complexes to a clade of flowering repressors that are silenced epigenetically via histone modifications. We also discuss the similarities and differences in vernalization between Arabidopsis and cereals.
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Arabidopsis/fisiologia , Grão Comestível/fisiologia , Flores/fisiologia , Fenômenos Fisiológicos Vegetais , Estações do AnoRESUMO
PURPOSE: Coronavirus disease 2019 (COVID-19) has emerged as a serious threat to public health; anticancer-repositioning treatment strategy has been formulated to treat the disease. However, evidence supporting the efficacy and safety of repositioned anticancer treatment in treating COVID-19-infected non-cancer patients (CINPs) is limited. Therefore, this study analyzed published randomized controlled trials (RCTs) evaluating the impact of anticancer drugs compared to current standards of care (SOCs) on CINP treatment. MATERIALS AND METHODS: The PubMed and Embase databases were searched to identify eligible RCTs. Outcome measures included mortality, the use of mechanical ventilation (MV), and serious adverse events (SAEs). RESULTS: 25 RCTs were reviewed in our study. Compared to SOCs, repositioned anticancer therapy for treating CINPs was associated with mortality reduction (odds ratio (OR) = 0.78, 95% confidence interval (CI) = 0.65 - 0.94, p = 0.01). Using the repositioned anticancer treatment exhibited statistically significant reduction, in both the number of CINPs using MV (OR = 0.67, 95% CI = 0.51 - 0.88, p = 0.004) and experiencing SAEs (OR = 0.79, 95% CI = 0.69 - 0.91, p = 0.0009). CONCLUSION: Conclusively, repositioned anticancer treatment was shown significant differences from SOCs in treating CINPs, which appears to be more associated with mortality, MV use, and SAE development reduction in CINPs.
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COVID-19 , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Prions are infectious protein particles known to cause prion diseases. The biochemical entity of the pathogen is the misfolded prion protein (PrPSc) that forms insoluble amyloids to impair brain function. PrPSc interacts with the non-pathogenic, cellular prion protein (PrPC) and facilitates conversion into a nascent misfolded isoform. Several small molecules have been reported to inhibit the aggregation of PrPSc but no pharmacological intervention was well established thus far. We, here, report that acylthiosemicarbazides inhibit the prion aggregation. Compounds 7x and 7y showed almost perfect inhibition (EC50 = 5 µM) in prion aggregation formation assay. The activity was further confirmed by atomic force microscopy, semi-denaturing detergent agarose gel electrophoresis and real-time quaking induced conversion assay (EC50 = 0.9 and 2.8 µM, respectively). These compounds also disaggregated pre-existing aggregates in vitro and one of them decreased the level of PrPSc in cultured cells with permanent prion infection, suggesting their potential as a treatment platform. In conclusion, hydroxy-2-naphthoylthiosemicarbazides can be an excellent scaffold for the discovery of anti-prion therapeutics.
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Doenças Priônicas , Príons , Humanos , Príons/metabolismo , Proteínas Priônicas/metabolismo , Encéfalo , Doenças Priônicas/tratamento farmacológico , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Células CultivadasRESUMO
KEY MESSAGE: Nonsense-mediated mRNA decay (NMD)-mediated degradation of BrFLC2 transcripts is the main cause of rapid flowering of oilseed-type B. rapa 'LP08' plants. Many Brassica species require vernalization (long-term winter-like cooling) for transition to the reproductive stage. In the past several decades, scientific efforts have been made to discern the molecular mechanisms underlying vernalization in many species. Thus, to identify the key regulators required for vernalization in Brassica rapa L., we constructed a linkage map composed of 7833 single nucleotide polymorphism markers using the late-flowering Chinese cabbage (B. rapa L. ssp. pekinensis) inbred line 'Chiifu' and the early-flowering yellow sarson (B. rapa L. ssp. trilocularis) line 'LP08' and identified a single major QTL on the upper-arm of the chromosome A02. In addition, we compared the transcriptomes of the lines 'Chiifu' and 'LP08' at five vernalization time points, including both non-vernalized and post-vernalization conditions. We observed that BrFLC2 was significantly downregulated in the early flowering 'LP08' and had two deletion sites (one at 4th exon and the other at 3' downstream region) around the BrFLC2 genomic region compared with the BrFLC2 genomic region in 'Chiifu'. Large deletion at 3' downstream region did not significantly affect transcription of both sense BrFLC2 transcript and antisense transcript, BrFLC2as along vernalization time course. However, the other deletion at 4th exon of BrFLC2 resulted in the generation of premature stop codon in BrFLC2 transcript in LP08 line. Cycloheximide treatment of LP08 line showed the de-repressed level of BrFLC2 in LP08, suggesting that low transcript level of BrFLC2 in LP08 might be caused by nonsense-mediated mRNA decay removing the nonsense transcript of BrFLC2. Collectively, this study provides a better understanding of the molecular mechanisms underlying floral transition in B. rapa.
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Brassica rapa/genética , Brassica rapa/fisiologia , Códon de Terminação/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/metabolismo , Sequência de Bases , DNA de Plantas , Genoma de Planta , Mutação , Proteínas de Plantas/genética , Locos de Características QuantitativasRESUMO
pH sensors that are nanoscopic in all three dimensions are fabricated within a single gold nanowire. Fabrication involves the formation of a nanogap within the nanowire via electromigration, followed by electropolymerization of pH-responsive poly(aniline) (PANI) that fills the nanogap forming the nanojunction. All fabrication steps are performed using wet chemical methods that do not require a clean room. The measured electrical impedance of the PANI nanojunction is correlated with pH from 2.0 to 9.0 with a response time of 30 s. Larger, micrometer-scale PANI junctions exhibit a slower response. The measured pH is weakly influenced by the salt concentration of the contacting aqueous solution. An impedance measurement at two frequencies (300 kHz and 1.0 Hz) enables estimation of the salt concentration and correction of the measured pH value, preserving the accuracy of the pH measurement across the entire calibration curve for salt concentrations up to 1.0 M. The result is a nanoscopic pH sensor with pH sensing performance approaching that of a conventional, macroscopic pH glass-membrane electrode.
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Nanofios , Eletrodos , Ouro , Concentração de Íons de HidrogênioRESUMO
OBJECTIVES: In HCC, locoregional therapy (LRT) is performed as a bridging or downstaging treatment before curative surgery. The impact of the LI-RADS Treatment Response (LR-TR) algorithm on surgical outcomes remains unknown. We aimed to evaluate radiologic and clinical factors predicting recurrence-free survival (RFS) and overall survival (OS) after curative surgery for LRT-treated HCC. MATERIALS AND METHODS: Consecutive HCC patients who underwent liver transplantation or curative resection after LRT from 2010 to 2016 and had baseline and follow-up post-LRT CT/MRI up to the point of surgery were included. The LR-TR category at the time of surgery and other features were assessed using Cox proportional hazard models. RFS was estimated and compared using the Kaplan-Meier method with log-rank tests. RESULTS: We evaluated 73 patients with 115 lesions. The LR-TR viable category at the time of surgery (hazard ratio [HR], 3.84; 95% confidence interval [CI]: 1.04, 14.16), preoperative AFP > 200 ng/mL (HR, 3.63; 95% CI: 1.63, 8.10), LRT sessions > 3 (HR, 4.99; 95% CI: 1.73, 14.38), and resection (HR, 3.35; 95% CI: 1.39, 8.09) independently predicted recurrence. The risk score categorized the patients into poor, intermediate, and favorable-risk groups with 1-year RFS rates of 35.0%, 78.3%, and 97.0%, respectively (p < 0.001). Outside Milan at the time of surgery (HR, 5.79; 95% CI: 1.94, 17.07) and recurrence within the first postoperative year (HR, 17.66; 95% CI: 6.42, 48.56) predicted death. CONCLUSION: In LRT-treated HCC, non-LR-TR viable disease achieved within fewer LRT sessions and removed by liver transplantation recurred less. KEY POINTS: ⢠The Liver Imaging Reporting and Data System treatment response (LR-TR) viable disease (hazard ratio [HR], 3.84; p = 0.043), preoperative serum AFP level > 200 ng/mL (HR, 3.63; p = 0.002), more than three locoregional treatment (LRT) sessions (HR, 4.99; p = 0.003), and resection compared to liver transplantation (HR, 3.35; p = 0.001) were the independent predictors for postsurgical recurrence in LRT-treated HCCs. ⢠A scoring system combining LR-TR categories and key clinical factors stratifies the patients into poor, intermediate, and favorable recurrence risk groups, with 1-year RFS rates of 35.0%, 78.3%, and 97.0%, respectively (p < 0.001). ⢠Outside Milan at the time of surgery (HR, 5.79; p = 0.001) and recurrence within the first postoperative year (HR, 17.66; p < 0.001) were associated with poor overall survival.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Algoritmos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/métodos , Recidiva Local de Neoplasia , Estudos Retrospectivos , alfa-FetoproteínasRESUMO
OBJECTIVES: To compare the prognosis of pancreatic ductal adenocarcinoma (PDAC) after curative resection according to the type of intratumoral fluid-containing area identified on MRI. METHODS: This retrospective study included 112 consecutive patients who underwent upfront surgery with margin-negative resection between 2012 and 2019. All patients underwent MRI within 1 month before surgery. Three radiologists independently assessed the MRI findings, determined whether intratumoral fluid-containing areas were present, and classified all intratumoral fluid-containing areas by type (i.e., imaging necrosis or neoplastic mucin cysts). Recurrence-free survival (RFS) and overall survival (OS) were evaluated by the Kaplan-Meier method and the Cox proportional hazards model. Histopathological differences according to the type of intratumoral fluid-containing area were assessed. RESULTS: Of the 112 PDAC patients, intratumoral fluid-containing areas were identified on MRI in 33 (29.5%), among which 18 were classified as imaging necrosis and 15 as neoplastic mucin cysts. PDAC patients with imaging necrosis demonstrated significantly shorter RFS (mean 6.1 months versus 47.3 months; p < .001) and OS (18.4 months versus 55.0 months, p = .001) than those with neoplastic mucin cysts. Multivariable analysis showed that only the type of intratumoral fluid-containing area was significantly associated with RFS (hazard ratio, 2.25 and 0.38; p = .009 and p = .046 for imaging necrosis and neoplastic mucin cysts, respectively). PDAC with imaging necrosis had more frequent histological necrosis, more aggressive tumor differentiation, and higher tumor cellularity than PDAC with neoplastic mucin cysts (p ≤ .02). CONCLUSION: The detection and discrimination of intratumoral fluid-containing areas on preoperative MRI may be useful in predicting the prognosis of PDAC patients after curative resection. KEY POINTS: ⢠Pancreatic ductal adenocarcinoma (PDAC) patients with imaging necrosis demonstrated significantly shorter survival than those with neoplastic mucin cysts after curative resection. ⢠Multivariable analysis showed that only the type of intratumoral fluid-containing area identified on MRI was significantly associated with recurrence-free survival. ⢠PDAC with imaging necrosis had more frequent histological necrosis, more aggressive tumor differentiation, and higher tumor cellularity than PDAC with neoplastic mucin cysts.