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Chemotherapy-induced peripheral neuropathy (CIPN) is a persistent and irreversible side effect of antineoplastic agents. Patients with CIPN usually show chronic pain and sensory deficits with glove-and-stocking distribution. However, whether spinal neuronal microRNA (miR)-124 is involved in cisplatin-induced peripheral neuropathy remains to be studied. In this study, miR-124 was significantly reduced in the spinal dorsal horn in CIPN mice. Overexpression of neuronal miR-124 induced by injecting adeno-associated virus with neuron-specific promoter into the spinal cord of mice prevented the development of mechanical allodynia, sensory deficits, and the loss of intraepidermal nerve fibers induced by cisplatin. Meanwhile, cisplatin-induced M1 microglia activation and the release of proinflammatory cytokines were significantly inhibited by overexpression of neuronal miR-124. Furthermore, electroacupuncture (EA) treatment upregulated miR-124 expression in the spinal dorsal horn of CIPN mice. Interestingly, downregulation of spinal neuronal miR-124 significantly inhibited the regulatory effect of EA on CIPN and microglia activity as well as spinal neuroinflammation induced by cisplatin. These results demonstrate that spinal neuronal miR-124 is involved in the prevention and treatment of EA on cisplatin-induced peripheral neuropathy in mice. Our findings suggest that spinal neuronal miR-124 might be a potential target for EA effect, and we provide, to our knowledge, a new experimental basis for EA prevention of CIPN.
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Antineoplásicos , Electroacupuntura , MicroARNs , Enfermedades del Sistema Nervioso Periférico , Humanos , Ratones , Animales , Cisplatino/toxicidad , Microglía , Paclitaxel/efectos adversos , Antineoplásicos/toxicidad , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/genética , Enfermedades del Sistema Nervioso Periférico/prevención & control , Neuronas/metabolismo , MicroARNs/genética , MicroARNs/metabolismoRESUMEN
Cellular eukaryotic replication initiation helicases are first loaded as head-to-head double hexamers on double-stranded (ds) DNA origins and then initiate S-phase DNA melting during licensed (once per cell cycle) replication. Merkel cell polyomavirus (MCV) large T (LT) helicase oncoprotein similarly binds and melts its own 98-bp origin but replicates multiple times in a single cell cycle. To examine the actions of this unlicensed viral helicase, we quantitated multimerization of MCV LT molecules as they assembled on MCV DNA origins using real-time single-molecule microscopy. MCV LT formed highly stable double hexamers having 17-fold longer mean lifetime (τ, >1,500 s) on DNA than single hexamers. Unexpectedly, partial MCV LT assembly without double-hexamer formation was sufficient to melt origin dsDNA as measured by RAD51, RPA70, or S1 nuclease cobinding. DNA melting also occurred with truncated MCV LT proteins lacking the helicase domain, but was lost from a protein without the multimerization domain that could bind only as a monomer to DNA. SV40 polyomavirus LT also multimerized to the MCV origin without forming a functional hexamer but still melted origin DNA. MCV origin melting did not require ATP hydrolysis and occurred for both MCV and SV40 LT proteins using the nonhydrolyzable ATP analog, adenylyl-imidodiphosphate (AMP-PNP). LT double hexamers formed in AMP-PNP, and melted DNA, consistent with direct LT hexamer assembly around single-stranded (ss) DNA without the energy-dependent dsDNA-to-ssDNA melting and remodeling steps used by cellular helicases. These results indicate that LT multimerization rather than helicase activity is required for origin DNA melting during unlicensed virus replication.
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Antígenos Transformadores de Poliomavirus , Virus 40 de los Simios , Antígenos Transformadores de Poliomavirus/genética , Antígenos Transformadores de Poliomavirus/metabolismo , Virus 40 de los Simios/genética , Virus 40 de los Simios/metabolismo , Desnaturalización de Ácido Nucleico , Adenilil Imidodifosfato , Replicación del ADN , ADN/genética , ADN/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismo , ADN de Cadena Simple , ADN Viral/genética , ADN Viral/metabolismoRESUMEN
The exploration of pharmaceutically active agents and positron emission tomography (PET) tracers targeting CXCR4 has been a focal point in cancer research given its pivotal role in the development and progression of various cancers. While significant strides have been made in PET imaging with radiometal-labeled tracers, the landscape of 18F-labeled small molecule tracers remains relatively limited. Herein, we introduce a novel and promising derivative, [18F]SFB-AMD3465, as a targeted PET tracer for CXCR4. The compound was synthesized by modifying the pyridine ring of AMD3465, which was subsequently labeled with 18F using [18F]SFB. The study provides comprehensive insights into the design, synthesis, and biological evaluation of [18F]SFB-AMD3465. In vitro and in vivo assessments demonstrated the CXCR4-dependent, specific, and sensitive uptake of [18F]SFB-AMD3465 in the CXCR4-overexpressing 4T1 cell line and the corresponding xenograft-bearing mouse model. These findings contribute to bridging the gap in 18F-labeled PET tracers for CXCR4 and underscore the potential of [18F]SFB-AMD3465 as a PET radiotracer for in vivo CXCR4 imaging.
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Radioisótopos de Flúor , Tomografía de Emisión de Positrones , Receptores CXCR4 , Animales , Receptores CXCR4/análisis , Receptores CXCR4/metabolismo , Tomografía de Emisión de Positrones/métodos , Ratones , Radioisótopos de Flúor/química , Femenino , Línea Celular Tumoral , Humanos , Piridinas/química , Piridinas/farmacocinética , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Radiofármacos/química , Radiofármacos/farmacocinética , Distribución TisularRESUMEN
Both COA and AOA have a genetically causal effect on osteoporosis. COA and AOA were independently associated with incident osteoporosis, and the risk was greatly higher in AOA. Besides corticosteroids, the increased risk of osteoporosis among asthma patients should be attributed to genetic susceptibility and other asthma medications. PURPOSE/INTRODUCTION: Childhood-onset asthma (COA) differs with adult-onset asthma (AOA) on genetic susceptibility, severity, and co-morbidities. Whether COA or AOA is independently associated with osteoporosis is unexplored. We aimed to determine the effects of COA and AOA on osteoporosis at genetic and individual level. METHODS: We used two-sample Mendelian randomization analysis to explore the causal effects of COA and AOA on osteoporosis. In the UK Biobank cohort, we included 478,289 osteoporosis-free participants at baseline (2006-2010). Participants were classified as non-asthma, COA, and AOA at recruitment. Multivariate Cox regression analysis was used to evaluate the effects of COA, AOA, and multiple asthma medications on incident osteoporosis risk. RESULTS: COA and AOA were causally related to osteoporosis, with odds ratio of 1.007 (95% confidence interval (CI), 1.0003-1.0132) and 1.012 (95% CI, 1.002-1.023), respectively. Multivariate Cox regression analysis suggested that COA (hazard ratio (HR), 1.46; 95% CI, 1.32-1.61) and AOA (HR, 1.70; 95% CI, 1.61-1.80) were independently associated with incident osteoporosis, and the risk was greatly higher in AOA (HR, 1.51; 95% CI, 1.34-1.70). In addition to corticosteroids, monotherapy with leukotriene modifiers (HR, 1.70; 95% CI, 1.20-2.42), long-acting beta agonists (HR, 1.49; 95% CI, 1.18-1.87), and short-acting beta agonists (HR, 1.72; 95% CI1.01-2.93) were independently associated with a higher risk of osteoporosis. CONCLUSIONS: Both COA and AOA have a genetically causal effect on osteoporosis, and the risk of osteoporosis is greatly higher in AOA. Besides corticosteroids, the increased risk of osteoporosis among asthma patients should be attributed to genetic susceptibility and other asthma medications.
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Asma , Osteoporosis , Adulto , Niño , Humanos , Corticoesteroides/efectos adversos , Asma/complicaciones , Asma/tratamiento farmacológico , Asma/genética , Predisposición Genética a la Enfermedad , Osteoporosis/etiología , Osteoporosis/genética , Estudios Prospectivos , Análisis de la Aleatorización MendelianaRESUMEN
OBJECTIVE: To evaluate the clinical significance of subtyping (type 1 vs 2) of papillary renal cell carcinoma (PRCC) in patients treated with targeted therapy, as well as the concordance, sensitivity and positive predictive value (PPV) of local review pathology review. METHODS: Patients with advanced refractory PRCC were randomised to receive sunitinib or cabozantinib, crizotinib or savolitinib, stratified by PRCC subtype (type 1, type 2, or not otherwise specified [NOS]/mixed) by local review. Central review was retrospectively conducted by three expert genitourinary pathologists who independently reviewed cases. The sensitivity and PPV of local review were estimated and outcomes [objective response rate (ORR), progression-free survival (PFS)] were summarised for treatment groups stratified by subtypes by central review. RESULTS: Amongst the 147 patients reviewed, the prevalence of individual subtypes varied by local or central review (type 1: 17.7% vs 29.3%; type 2: 53.1% vs 45.6%; NOS/mixed: 29.3% vs 25.2%), respectively. Individual cases were frequently reclassified and local pathology review demonstrated low sensitivity (type 1: 48%, 95% confidence interval [CI] 33, 65; type 2: 67%, 95% CI 55, 78; NOS/mixed: 43%, 95% CI 27, 61). The PPVs of local review were 80%, 57.7% and 37% for type 1, 2 and NOS/mixed, respectively. Compared to sunitinib, cabozantinib demonstrated improved PFS for both type 1 and type 2 PRCC subgroups (7.4 vs 9.0 and 2.9 vs 5.6 months, respectfully) as well as higher ORR. CONCLUSIONS: The PRCC subtype assignment did not identify a subset of patients with greater clinical benefit from cabozantinib, with significant discordance between local and central review. Our findings confirm the limited clinical value of pathological subtyping of metastatic PRCC, in line with the recent World Health Organisation 2022 guidelines. PATIENT SUMMARY: In this study, categorising papillary renal cell carcinoma into type 1 or 2 subtypes showed limited concordance between central and local pathological review and did not enrich for patients more likely to benefit from cabozantinib in the S1500 PAPMET trial.
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OBJECTIVES: To characterise the restrictiveness of eligibility criteria in contemporary renal cell carcinoma (RCC) trials, using recommendations from the American Society of Clinical Oncology (ASCO)-Friends of Cancer Research (FCR) initiative. METHODS: vPhase I-III trials assessing systemic therapies in patients with RCC starting between 30 June 2012 and 30 June 2022 were identified. Eligibility criteria regarding brain metastases, prior or concurrent malignancies, hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, and human immunodeficiency virus (HIV) infection were identified and stratified into three groups: exclusion, conditional inclusion, and not reported. Descriptive statistics were used to determine the frequency of eligibility criteria. Fisher's exact test or chi-square test were used to calculate their associations with certain trial characteristics. RESULTS: A total of 423 RCC trials were initially identified of which 112 (26.5%) had sufficient accessible information. Exclusion of patients with HIV infection, HBV/HCV infection, brain metastases, and prior or concurrent malignancies were reported in 74.1%, 53.6%, 33.0%, and 8.0% of trials, respectively. In the context of HIV and HBV/HCV infection, patients were largely excluded from trials evaluating immunotherapy (94.4% and 77.8%, respectively). In addition, brain metastases were excluded in trials assessing targeted therapy (36.4%), combined therapy (33.3%), and immunotherapy (22.2%). Exclusion of patients with prior or concurrent malignancies was less frequently reported, accounting for 9.1%, 8.3%, and 5.6% targeted therapy, combined therapy and immunotherapy trials, respectively. CONCLUSION: A substantial proportion of RCC trials utilise restrictive eligibility criteria, excluding patients with fairly prevalent comorbidities. Implementing the ASCO-FCR recommendations will ensure resulting data are more inclusive and aligned with patient populations in the real-world.
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Neoplasias Encefálicas , Carcinoma de Células Renales , Infecciones por VIH , Hepatitis C , Neoplasias Renales , Humanos , Carcinoma de Células Renales/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológicoRESUMEN
BACKGROUND: Nasopharyngeal carcinoma (NPC) is a type of malignant tumor with high morbidity. Aberrant levels of N7-methylguanosine (m7G) are closely associated with tumor progression. However, the characteristics of the tumor microenvironment (TME) in NPC associated with m7G modification remain unclear. METHODS: A total of 68,795 single cells from single-cell RNA sequencing data derived from 11 NPC tumor samples and 3 nasopharyngeal lymphatic hyperplasia (NLH) samples were clustered using a nonnegative matrix factorization algorithm according to 61 m7G RNA modification regulators. RESULTS: The m7G regulators were found differential expression in the TME cells of NPC, and most m7G-related immune cell clusters in NPC tissues had a higher abundance compared to non-NPC tissues. Specifically, m7G scores in the CD4+ and CD8+ T cell clusters were significantly lower in NPC than in NLH. T cell clusters differentially expressed immune co-stimulators and co-inhibitors. Macrophage clusters differentially expressed EIF4A1, and high EIF4A1 expression was associated with poor survival in patients with head and neck squamous carcinoma. EIF4A1 was upregulated in NPC tissues compared to the non-NPC tissues and mainly expressed in CD86+ macrophages. Moreover, B cell clusters exhibited tumor biological characteristics under the regulation of m7G-related genes in NPC. The fibroblast clusters interacted with the above immune cell clusters and enriched tumor biological pathways, such as FGER2 signaling pathway. Importantly, there were correlations and interactions through various ligand-receptor links among epithelial cells and m7G-related TME cell clusters. CONCLUSION: Our study revealed tumor-associated characteristics and immune dysregulation in the NPC microenvironment under the regulation of m7G-related TME cells. These results demonstrated the underlying regulatory roles of m7G in NPC.
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Regulación Neoplásica de la Expresión Génica , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Microambiente Tumoral , Humanos , Microambiente Tumoral/inmunología , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/inmunología , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/inmunología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Pronóstico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Masculino , Tasa de Supervivencia , FemeninoRESUMEN
Polyacrylamide (PAM) is a high-molecular-weight polymer with extensive applications. However, the inefficient natural degradation of PAM results in environmental accumulation of the polymer. Biodegradation is an environmentally friendly approach in the field of PAM treatment. The first phase of PAM biodegradation is the deamination of PAM, forming the product poly(acrylic acid) (PAA). The second phase of PAM biodegradation involves the cleavage of PAA into small molecules, which is a crucial step in the degradation pathway of PAM. However, the enzyme that catalyzes the degradation of PAA and the molecular mechanism remain unclear. Here, a novel monooxygenase PCX02514 is identified as the key enzyme for PAA degradation. Through biochemical experiments, the monooxygenase PCX02514 oxidizes PAA with the participation of NADPH, causing the cleavage of carbon chains and a decrease in the molecular weight of PAA. In addition, the crystal structure of the monooxygenase PCX02514 is solved at a resolution of 1.97 Å. The active pocket is in a long cavity that extends from the C-terminus of the TIM barrel to the protein surface and exhibits positive electrostatic potential, thereby causing the migration of oxygen-negative ions into the active pocket and facilitating the reaction between the substrates and monooxygenase PCX02514. Moreover, Arg10-Arg125-Ser186-Arg187-His253 are proposed as potential active sites in monooxygenase PCX02514. Our research characterizes the molecular mechanism of this monooxygenase, providing a theoretical basis and valuable tools for PAM bioremediation.
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Resinas Acrílicas , Biodegradación Ambiental , Oxigenasas de Función Mixta , Resinas Acrílicas/química , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Dominio Catalítico , Modelos Moleculares , Cristalografía por Rayos X , Conformación ProteicaRESUMEN
The widespread use of antibiotics and the inefficiency of traditional degradation treatments pose threats to the environment and human health. Previous studies have reported the potential of bio-electro-Fenton (BEF) processes for antibiotic removal. However, some drawbacks, such as a strict pH range of 2-3 and iron sludge generation, limit their large-scale application. Thus, to overcome the narrow pH range of traditional BEF processes, a photo-BEF (PBEF) system was established using a novel FeMn-layered double hydroxide (LDH)/graphitic carbon nitride (g-C3N4) (FM/CN) composite cathode. The performance of the PBEF system was investigated by degrading tetracycline (TC) under low-power LED lamp irradiation. The results indicated that the pH range of the PBEF system could be expanded to 3-11 using an FM/CN cathode, which exhibited a TC removal efficiency of 63.0%-75.9%. The highest TC removal efficiency was achieved at pH 7. The efficient mineralization of TC by the PBEF system can be high, up to 67.6%. In addition, the TC removal mechanism was discussed in terms of reactive oxygen species, TC degradation intermediate analyses, and density functional theory (DFT) calculations. Strong oxidative hydroxyl radicals (·OH) were the dominant reactive oxidizing species in the PBEF system, followed by ·O2- and h+. Three pathways of TC degradation were proposed based on the analysis of intermediates, and the reactive sites attacked by electrophilic reagents were explored using DFT modeling. In addition, the overall toxicity of TC degradation intermediates effectively decreased in the PBEF system. This work offers deep insights into the TC removal mechanisms and performance of the PBEF system over a wide pH range of 3-11.
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Electrodos , Tetraciclina , Concentración de Iones de Hidrógeno , Tetraciclina/química , Peróxido de Hidrógeno/química , Hierro/química , Grafito/química , Especies Reactivas de Oxígeno/química , Compuestos de NitrógenoRESUMEN
Diabetic kidney disease (DKD), has become the main cause of end-stage renal disease (ESRD) worldwide. Lately, it has been shown that the onset and advancement of DKD are linked to imbalances of gut microbiota and the abnormal generation of microbial metabolites. Similarly, a body of recent evidence revealed that biological alterations of mitochondria ranging from mitochondrial dysfunction and morphology can also exert significant effects on the occurrence of DKD. Based on the prevailing theory of endosymbiosis, it is believed that human mitochondria originated from microorganisms and share comparable biological characteristics with the microbiota found in the gut. Recent research has shown a strong correlation between the gut microbiome and mitochondrial function in the occurrence and development of metabolic disorders. The gut microbiome's metabolites may play a vital role in this communication. However, the relationship between the gut microbiome and mitochondrial function in the development of DKD is not yet fully understood, and the role of microbial metabolites is still unclear. Recent studies are highlighted in this review to examine the possible mechanism of the gut microbiota-microbial metabolites-mitochondrial axis in the progression of DKD and the new therapeutic approaches for preventing or reducing DKD based on this biological axis in the future.
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Diabetes Mellitus , Nefropatías Diabéticas , Microbioma Gastrointestinal , Microbiota , Humanos , MitocondriasRESUMEN
BACKGROUND: There are limited data regarding the impact of ethnicity among patients receiving immune checkpoint inhibitors. We evaluated real-world outcomes between Latinx and non-Latinx patients with metastatic renal-cell carcinoma (mRCC) treated with first-line nivolumab/ipilimumab within 2 different healthcare settings. METHODS: We performed a retrospective analysis of patients with mRCC who received nivolumab/ipilimumab within the Los Angeles County Department of Health Services (LAC-DHS), a safety-net healthcare system, and the City of Hope Comprehensive Cancer Center (COH), a tertiary oncology center, between January 1, 2015 and December 31, 2021. Progression-free survival (PFS) and overall survival (OS) were determined using the Kaplan-Meier method and covariates were adjusted using multivariate Cox proportional hazards regression. RESULTS: Of 94 patients, 40 patients (43%) were Latinx while the remainder were non-Latinx (44 pts [46%] White, 7 pts [7%] Asian, and 3 pts [3%] Other). Fifty (53%) and 44 (47%) patients received their care at COH and LAC-DHS, respectively. Most Latinx patients (95%) were treated at LAC-DHS, and most non-Latinx patients (89%) were treated at COH. Pooled analysis by ethnicity demonstrated significantly shorter PFS in Latinx versus non-Latinx patients (10.1 vs. 25.2 months, hazard ratios [HR] 3.61, 95% CI 1.96-6.66, P ≤ .01). Multivariate analysis revealed a HR of 3.41 (95% CI 1.31-8.84; P = .01). At a median follow-up of 11.0 months, the median OS was not reached in either arm at the time of data cutoff. CONCLUSION: Latinx patients with mRCC had a shorter PFS treated with frontline nivolumab/ipilimumab compared to their non-Latinx counterparts. No difference was observed in OS although these data were immature. Larger studies are needed to further interrogate the social and economic determinants of ethnicity on clinical outcomes in mRCC.
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Antineoplásicos Inmunológicos , Carcinoma de Células Renales , Inhibidores de Puntos de Control Inmunológico , Neoplasias Renales , Humanos , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/patología , Hispánicos o Latinos , Ipilimumab/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Nivolumab/uso terapéutico , Estudios Retrospectivos , Inhibidores de Puntos de Control Inmunológico/uso terapéuticoRESUMEN
BACKGROUND: Nasopharyngeal carcinoma (NPC), especially the nonkeratinizing type, is a malignant tumor primarily occurring in southern China and Southeast Asia. Chemotherapy (CT) and combined radiotherapy (RT) is used to treat NPC. However, the mortality rate is high in recurrent and metastatic NPC. We developed a molecular marker, analyzed its correlation with clinical characteristics, and assessed the prognostic value among NPC patients with or without chemoradiotherapy. METHODS: A total of 157 NPC patients were included in this study, with 120 undergoing treatment and 37 without treatment. EBER1/2 expression was investigated using in situ hybridization (ISH). Expression of PABPC1, Ki-67, and p53 was detected with immunohistochemistry. The correlations of EBER1/2 and the expression of the three proteins having clinical features and prognosis were evaluated. RESULTS: The expression of PABPC1 was associated with age, recurrence, and treatment but not with gender, TNM classification, or the expression of Ki-67, p53, or EBER. High expression of PABPC1 was associated with poor overall survival (OS) and disease-free survival (DFS) and was an independent predictor depending on multivariate analysis. Comparatively, no significant correlation was observed between the expression of p53, Ki-67, and EBER and survival. In this study, 120 patients received treatments and revealed significantly better OS and DFS than the untreated 37 patients. PABPC1 high expression was an independent predictor of shorter OS in the treated (HR = 4.012 (1.238-13.522), 95% CI, p = 0.021) and the untreated groups (HR = 5.473 (1.051-28.508), 95% CI, p = 0.044). However, it was not an independent predictor of shorter DFS in either the treated or the untreated groups. No significant survival difference was observed between patients with docetaxel-based induction chemotherapy (IC) + concurrent chemoradiotherapy (CCRT) and those with paclitaxel-based IC + CCRT. However, when combined with treatment and PABPC1 expression, patients with paclitaxel-added chemoradiotherapy plus PABPC1 low expression had significantly better OS than those who underwent chemoradiotherapy (p = 0.036). CONCLUSIONS: High expression of PABPC1 is associated with poorer OS and DFS among NPC patients. Patients with PABPC1 having low expression revealed good survival irrespective of the treatment received, indicating that PABPC1 could be a potential biomarker for triaging NPC patients.
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Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteína I de Unión a Poli(A) , Humanos , Quimioradioterapia , Quimioterapia de Inducción , Antígeno Ki-67 , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/terapia , Paclitaxel/uso terapéutico , Proteínas de Unión a Poli(A) , Pronóstico , Proteína p53 Supresora de Tumor , Proteína I de Unión a Poli(A)/genéticaRESUMEN
BACKGROUND: Spinosad is a macrolide insecticide with the tetracyclic lactone backbone to which forosamine and tri-O-methylrhamnose are attached. Both the sugar moieties are essential for its insecticidal activity. In biosynthesis of spinosad, the amino group of forosamine is dimethylated by SpnS and then transferred onto the lactone backbone by SpnP. Because the spinosad native producer is difficult to genetically manipulate, we previously changed promoters, ribosome binding sites and start codons of 23 spinosad biosynthetic genes to construct an artificial gene cluster which resulted in a 328-fold yield improvement in the heterologous host Streptomyces albus J1074 compared with the native gene cluster. However, in fermentation of J1074 with the artificial gene cluster, the N-monodesmethyl spinosad with lower insecticidal activity was always produced with the same titer as spinosad. RESULTS: By tuning expression of SpnS with an inducible promotor, we found that the undesired less active byproduct N-monodesmethyl spinosad was produced when SpnS was expressed at low level. Although N-monodesmethyl spinosad can be almost fully eliminated with high SpnS expression level, the titer of desired product spinosad was only increased by less than 38%. When the forosaminyl transferase SpnP was further overexpressed together with SpnS, the titer of spinosad was improved by 5.3 folds and the content of N-desmethyl derivatives was decreased by ~ 90%. CONCLUSION: N-monodesmethyl spinosad was produced due to unbalanced expression of spnS and upstream biosynthetic genes in the refactored artificial gene cluster. The accumulated N-desmethyl forosamine was transferred onto the lactone backbone by SpnP. This study suggested that balanced expression of biosynthetic genes should be considered in the refactoring strategy to avoid accumulation of undesired intermediates or analogues which may affect optimal production of desired compounds.
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Streptomyces griseus , Transferasas , Transferasas/genética , Metiltransferasas/genética , Streptomyces griseus/metabolismo , Macrólidos/metabolismo , Familia de MultigenesRESUMEN
BACKGROUND: Biological nitrogen fixation converting atmospheric dinitrogen to ammonia is an important way to provide nitrogen for plants. Pseudomonas stutzeri DSM4166 is a diazotrophic Gram-negative bacterium isolated from the rhizosphere of cereal Sorghum nutans. Endogenous constitutive promoters are important for engineering of the nitrogen fixation pathway, however, they have not been systematically characterized in DSM4166. RESULTS: Twenty-six candidate promoters were identified from DSM4166 by RNA-seq analysis. These 26 promoters were cloned and characterized using the firefly luciferase gene. The strengths of nineteen promoters varied from 100 to 959% of the strength of the gentamicin resistance gene promoter. The strongest P12445 promoter was used to overexpress the biological nitrogen fixation pathway-specific positive regulator gene nifA. The transcription level of nitrogen fixation genes in DSM4166 were significantly increased and the nitrogenase activity was enhanced by 4.1 folds determined by the acetylene reduction method. The nifA overexpressed strain produced 359.1 µM of extracellular ammonium which was 25.6 times higher than that produced by the wild-type strain. CONCLUSIONS: The endogenous strong constitutive promoters identified in this study will facilitate development of DSM4166 as a microbial cell factory for nitrogen fixation and production of other useful compounds.
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Pseudomonas stutzeri , Pseudomonas stutzeri/genética , Pseudomonas stutzeri/metabolismo , Rizosfera , Fijación del Nitrógeno/genética , Nitrógeno/metabolismo , Nitrogenasa/genética , Nitrogenasa/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión GénicaRESUMEN
BACKGROUND: To investigate the changes and clinical significance of vascular endothelial injury markers in type 2 diabetes mellitus (T2DM) complicated with pulmonary embolism (PE). METHODS: This prospective study enrolled patients with T2DM hospitalized in one hospital from January 2021 to June 2022. Soluble thrombomodulin (sTM) (ELISA), von Willebrand factor (vWF) (ELISA), and circulating endothelial cells (CECs) (flow cytometry) were measured. PE was diagnosed by computed tomography pulmonary angiography (CTPA). RESULTS: Thirty participants were enrolled in each group. The plasma levels of sTM (151.22 ± 120.57 vs. 532.93 ± 243.82 vs. 1016.51 ± 218.00 pg/mL, P < 0.001) and vWF (9.63 ± 2.73 vs. 11.50 ± 2.17 vs. 18.02 ± 3.40 ng/mL, P < 0.001) and the percentage of CECs (0.17 ± 0.46 vs. 0.30 ± 0.08 vs. 0.56 ± 0.18%, P < 0.001) gradually increased from the control group to the T2DM group to the T2DM + PE group. sTM (OR = 1.002, 95%CI: 1.002-1.025, P = 0.022) and vWF (OR = 1.168, 95%CI: 1.168-2.916, P = 0.009) were associated with T2DM + PE. sTM > 676.68 pg/mL for the diagnosis of T2DM + PE achieved an AUC of 0.973, while vWF > 13.75 ng/mL achieved an AUC of 0.954. The combination of sTM and vWF above their cutoff points achieved an AUC of 0.993, with 100% sensitivity and 96.7% specificity. CONCLUSIONS: Patients with T2DM show endothelial injury and dysfunction, which were worse in patients with T2DM and PE. High sTM and vWF levels have certain clinical predictive values for screening T2DM accompanied by PE.
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Diabetes Mellitus Tipo 2 , Embolia Pulmonar , Humanos , Células Endoteliales , Diabetes Mellitus Tipo 2/complicaciones , Factor de von Willebrand/análisis , Estudios Prospectivos , Endotelio Vascular/química , BiomarcadoresRESUMEN
BACKGROUND: As a complex vascular malformation, fibro-adipose vascular anomaly was first proposed in 2014. Its overlap with other vascular malformations regarding imaging and clinical features often leads to misdiagnosis and improper management. OBJECTIVE: To construct a radiomics-based machine learning model to help radiologists differentiate fibro-adipose vascular anomaly from common venous malformations. MATERIALS AND METHODS: We retrospectively analyzed 178 children, adolescents and young adults with vascular malformations (41 fibro-adipose vascular anomaly and 137 common vascular malformation cases) who underwent MRI before surgery between May 2012 to January 2021. We extracted radiomics features from T1-weighted images and fat-saturated (FS) T2-weighted images and further selected features through least absolute shrinkage and selection operator (LASSO) and Boruta methods. We established eight weighted logistic regression classification models based on various combinations of feature-selection strategies (LASSO or Boruta) and sequence types (single- or multi-sequence). Finally, we evaluated the performance of each model by the mean area under the receiver operating characteristics curve (ROC-AUC), sensitivity and specificity in 10 runs of repeated k-fold (k = 10) cross-validation. RESULTS: Two multi-sequence models based on axial FS T2-W, coronal FS T2-W and axial T1-W images showed promising performance. The LASSO-based multi-sequence model achieved an AUC of 97%±3.8, a sensitivity of 94%±12.4 and a specificity of 89%±9.0. The Boruta-based multi-sequence model achieved an AUC of 97%±3.7, a sensitivity of 95%±10.5 and a specificity of 87%±9.0. CONCLUSION: The radiomics-based machine learning model can provide a promising tool to help distinguish fibro-adipose vascular anomaly from common venous malformations.
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Enfermedades Pulmonares , Malformaciones Vasculares , Adulto Joven , Adolescente , Niño , Humanos , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Sensibilidad y Especificidad , Aprendizaje AutomáticoRESUMEN
To assess the value of parameters of myocardial work for dynamic monitoring of myocardial injury after neonatal asphyxia. Fifty-three neonates with asphyxia admitted within 24 h after delivery were divided into a mild asphyxia group (n = 40) and severe asphyxia group (n = 13). Echocardiography was performed within 24 h post-birth, within 72 h post-birth (48 h after first echo), and during recovery. The left ventricular ejection fraction on M-mode echocardiography and by Simpson's biplane method (LVEF and Bi-EF, respectively), stroke volume (SV), cardiac output (CO), cardiac index (CI), global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), and other parameters were measured. Echocardiographic indicators were compared between groups and over time. GWI was significantly increased at 72 h in the mild asphyxia group (P < 0.05) but showed no significant change over time in the severe asphyxia group (P > 0.05). While GCW increased significantly over time in both groups (P < 0.05), it increased earlier in the mild asphyxia group. Time and grouping factors had independent effects on GWI and GCW (P > 0.05). The characteristics of differences in GWI and GCW between the two groups were different from those for LVEF, Bi-EF, SV, CO, CI, and GLS and their change characteristics with improvement from treatment. GWI and GCW changed significantly during recovery from neonatal asphyxia, and their change characteristics differed between mild and severe asphyxia cases. Myocardial work parameters can be used as valuable supplements to traditional indicators of left ventricular function to dynamically monitor the recovery from myocardial injury after neonatal asphyxia.
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Common buckwheat (Fagopyrum esculentum) and Tartary buckwheat (Fagopyrum tataricum), the two most widely cultivated buckwheat species, differ greatly in flavonoid content and reproductive mode. Here, we report the first high-quality and chromosome-level genome assembly of common buckwheat with 1.2 Gb. Comparative genomic analysis revealed that common buckwheat underwent a burst of long terminal repeat retrotransposons insertion accompanied by numerous large chromosome rearrangements after divergence from Tartary buckwheat. Moreover, multiple gene families involved in stress tolerance and flavonoid biosynthesis such as multidrug and toxic compound extrusion (MATE) and chalcone synthase (CHS) underwent significant expansion in buckwheat, especially in common buckwheat. Integrated multi-omics analysis identified high expression of catechin biosynthesis-related genes in flower and seed in common buckwheat and high expression of rutin biosynthesis-related genes in seed in Tartary buckwheat as being important for the differences in flavonoid type and content between these buckwheat species. We also identified a candidate key rutin-degrading enzyme gene (Ft8.2377) that was highly expressed in Tartary buckwheat seed. In addition, we identified a haplotype-resolved candidate locus containing many genes reportedly associated with the development of flower and pollen, which was potentially related to self-incompatibility in common buckwheat. Our study provides important resources facilitating future functional genomics-related research of flavonoid biosynthesis and self-incompatibility in buckwheat.
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Fagopyrum , Flavonoides , Flavonoides/metabolismo , Fagopyrum/genética , Fagopyrum/metabolismo , Rutina/análisis , Rutina/metabolismo , Genes de Plantas , Semillas/genéticaRESUMEN
Hypoxic pulmonary hypertension (HPH) is characterized by elevated pulmonary artery resistance and vascular remodeling. Endoplasmic reticulum stress (ERS) is reported to be involved in HPH, but the underlying mechanisms remain uncertain. We found that Xbp1s, a potent transcription factor during ERS, was elevated in hypoxic-cultured rat PASMCs and lung tissues from HPH rats. Our in vitro experiments demonstrated that overexpressing Xbp1s can promote proliferation, cell viability, and migration and inhibit the apoptosis of PASMCs, while silencing Xbp1s led to the opposite. Through data-independent acquisition (DIA) mass spectrometry, we identified extensive proteomic alterations regulated by hypoxia and Xbp1s. Further validation revealed that p-JNK, rather than p-ERK or p-p38, was the downstream effector of Xbp1s. p-JNK inhibition reversed the biological effects of Xbp1s overexpression in vitro. In the animal HPH model, rats were randomly assigned to five groups: normoxia, hypoxia, hypoxia+AAV-CTL (control), hypoxia+AAV-Xbp1s (prevention), and hypoxia+AAV-Xbp1s (therapy). Adeno-associated virus (AAV) serotype 1-mediated Xbp1s knockdown in the prevention and therapy groups significantly reduced right ventricular systolic pressure, total pulmonary resistance, right ventricular hypertrophy, and the medial wall thickness of muscularized distal pulmonary arterioles; AAV-Xbp1s also decreased proliferating cell nuclear antigen expression and increased apoptosis in pulmonary arterioles. Collectively, our findings demonstrated that the Xbp1s-p-JNK pathway is important in hypoxic vascular remodeling and that targeting this pathway could be an effective strategy to prevent and alleviate HPH development.
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Hipertensión Pulmonar , Sistema de Señalización de MAP Quinasas , Proteína 1 de Unión a la X-Box , Animales , Proliferación Celular/genética , Modelos Animales de Enfermedad , Hipertensión Pulmonar/metabolismo , Hipoxia/metabolismo , Miocitos del Músculo Liso/metabolismo , Proteómica , Arteria Pulmonar/metabolismo , Ratas , Ratas Sprague-Dawley , Remodelación Vascular , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismoRESUMEN
Liquid-phase electron microscopy is highly desirable for observing biological samples in their native liquid state at high resolution. We developed liquid imaging approaches for biological cells using scanning electron microscopy. Novel approaches included scanning transmission electron imaging using a liquid-cell apparatus (LC-STEM), as well as correlative cathodoluminescence and electron microscopy (CCLEM) imaging. LC-STEM enabled imaging at a â¼2 nm resolution and excellent contrast for the precise recognition of localization, distribution, and configuration of individually labeled membrane proteins on the native cells in solution. CCLEM improved the resolution of fluorescent images down to 10 nm. Liquid SEM technologies will bring unique and wide applications to the study of the structure and function of cells and membrane proteins in their near-native states at the monomolecular level.