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The influenza A virus (IAV) consists of 8 single-stranded, negative-sense viral RNA (vRNA) segments. After infection, vRNA is transcribed, replicated, and wrapped by viral nucleoprotein (NP) to form viral ribonucleoprotein (vRNP). The transcription, replication, and nuclear export of the viral genome are regulated by the IAV protein, NS2, which is translated from spliced mRNA transcribed from viral NS vRNA. This splicing is inefficient, explaining why NS2 is present in low abundance after IAV infection. The levels of NS2 and its subsequent accumulation are thought to influence viral RNA replication and vRNP nuclear export. Here we show that NS2 is ubiquitinated at the K64 and K88 residues by K48-linked and K63-linked polyubiquitin (polyUb) chains, leading to the degradation of NS2 by the proteasome. Additionally, we show that a host deubiquitinase, OTUB1, can remove polyUb chains conjugated to NS2, thereby stabilizing NS2. Accordingly, knock down of OTUB1 by siRNA reduces the nuclear export of vRNP, and reduces the overall production of IAV. These results collectively demonstrate that the levels of NS2 in IAV-infected cells are regulated by a ubiquitination-deubiquitination system involving OTUB1 that is necessary for optimal IAV replication.
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Cisteína Endopeptidasas , Virus de la Influenza A , Proteínas no Estructurales Virales , Replicación Viral , Animales , Perros , Humanos , Cisteína Endopeptidasas/metabolismo , Cisteína Endopeptidasas/genética , Enzimas Desubicuitinizantes/metabolismo , Células HEK293 , Virus de la Influenza A/metabolismo , Gripe Humana/metabolismo , Gripe Humana/virología , ARN Viral/metabolismo , ARN Viral/genética , Ubiquitinación , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/genética , Replicación Viral/fisiología , Línea Celular , Células Vero , Chlorocebus aethiopsRESUMEN
Iridium-based electrocatalysts remain the only practical anode catalysts for proton exchange membrane (PEM) water electrolysis, due to their excellent stability under acidic oxygen evolution reaction (OER), but are greatly limited by their high cost and low reserves. Here, we report a nickel-stabilized, ruthenium dioxide (Ni-RuO2) catalyst, a promising alternative to iridium, with high activity and durability in acidic OER for PEM water electrolysis. While pristine RuO2 showed poor acidic OER stability and degraded within a short period of continuous operation, the incorporation of Ni greatly stabilized the RuO2 lattice and extended its durability by more than one order of magnitude. When applied to the anode of a PEM water electrolyser, our Ni-RuO2 catalyst demonstrated >1,000 h stability under a water-splitting current of 200 mA cm-2, suggesting potential for practical applications. Density functional theory studies, coupled with operando differential electrochemical mass spectroscopy analysis, confirmed the adsorbate-evolving mechanism on Ni-RuO2, as well as the critical role of Ni dopants in stabilization of surface Ru and subsurface oxygen for improved OER durability.
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OBJECTIVES: To explore the potential of dynamic contrast-enhanced MRI (DCE-MRI) quantitative parameters in predicting severe acute radiation-induced rectal injury (RRI) in rectal cancer. METHODS: This retrospective study enrolled 49 patients with rectal cancer who underwent neoadjuvant chemoradiotherapy and rectal MRI including a DCE-MRI sequence from November 2014 to March 2021. Two radiologists independently measured DCE-MRI quantitative parameters, including the forward volume transfer constant (Ktrans), rate constant (kep), fractional extravascular extracellular space volume (ve), and the thickness of the rectal wall farthest away from the tumor. These parameters were compared between mild and severe acute RRI groups based on histopathological assessment. Receiver operating characteristic curve analysis was performed to analyze statistically significant parameters. RESULTS: Forty-nine patients (mean age, 54 years ± 12 [standard deviation]; 37 men) were enrolled, including 25 patients with severe acute RRI. Ktrans was lower in severe acute RRI group than mild acute RRI group (0.032 min-1 vs 0.054 min-1; p = 0.008), but difference of other parameters (kep, ve and rectal wall thickness) was not significant between these two groups (all p > 0.05). The area under the receiver operating characteristic curve of Ktrans was 0.72 (95% confidence interval: 0.57, 0.84). With a Ktrans cutoff value of 0.047 min-1, the sensitivity and specificity for severe acute RRI prediction were 80% and 54%, respectively. CONCLUSION: Ktrans demonstrated moderate diagnostic performance in predicting severe acute RRI. CLINICAL RELEVANCE STATEMENT: Dynamic contrast-enhanced MRI can provide non-invasive and objective evidence for perioperative management and treatment strategies in rectal cancer patients with acute radiation-induced rectal injury. KEY POINTS: ⢠To our knowledge, this study is the first to evaluate the predictive value of contrast-enhanced MRI (DCE-MRI) quantitative parameters for severe acute radiation-induced rectal injury (RRI) in patients with rectal cancer. ⢠Forward volume transfer constant (Ktrans), derived from DCE-MRI, exhibited moderate diagnostic performance (AUC = 0.72) in predicting severe acute RRI of rectal cancer, with a sensitivity of 80% and specificity of 54%. ⢠DCE-MRI is a promising imaging marker for distinguishing the severity of acute RRI in patients with rectal cancer.
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Medios de Contraste , Neoplasias del Recto , Masculino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Recto/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/diagnóstico por imagenRESUMEN
Converting CO2 into valuable chemicals via sustainable energy sources is indispensable for human development. Photothermal catalysis combines the high selectivity of photocatalysis and the high yield of thermal catalysis, which is promising for CO2 reduction. However, the present photothermal catalysts suffer from low activity due to their poor light absorption ability and fast recombination of photogenerated electrons and holes. Here, a TiO2@Bi2WO6 heterojunction photocatalyst featuring a hierarchical hollow structure was prepared by an in situ growth method. The visible light absorption and photothermal effect of the TiO2@Bi2WO6 photocatalyst is promoted by a hierarchical hollow structure, while the recombination phenomenon is significantly mitigated due to the construction of the heterojunction interface and the existence of excited Bi(3-x)+ sites. Such a catalyst exhibits excellent photothermal performance with a CO yield of 43.7 µmol h-1 g-1, which is 15 and 4.7 times higher than that of pure Bi2WO6 and that of physically mixed TiO2/Bi2WO6, respectively. An in situ study shows that the pathway for the transformation of CO2 into CO over our TiO2@Bi2WO6 proceeds via two important intermediates, including COO- and COOH-. Our work provides a new idea of excited states for the design and synthesis of highly efficient photothermal catalysts for CO2 conversion.
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AIMS: This study aimed to characterize the first complete genome of Corynebacterium parakroppenstedtii and clarify the evolutionary relationship in the Corynebacterium kroppenstedtii complex (CKC) by using comparative genomics analysis. METHODS AND RESULTS: The genome of isolate yu01 from a breast specimen was sequenced, and 35 CKC genomes were collected. Analysis of 16S rRNA, rpoB, and fusA suggested ambiguous identification, whereas ANI analysis assigned isolate yu01 as Coryne. parakroppenstedtii. The fourth genospecies "Corynebacterium aliikroppenstedtii" was identified in CKC. Comparative genomics analysis suggested that the genomic arrangement in CKC was highly conserved. A total of 43 potential virulence genes and 79 species-specific genes were detected. Most genome-based phylogenetic analysis were incapable of resolving the interspecific evolutionary relationships among CKCs. A total of 20 core genes were found to be distinguishable in CKC. CONCLUSIONS: This study suggested the limited divergence and unavailability of normal single gene-based identification in CKC and questioned the precise species of strains associated with mastitis, identified as Coryne. kroppenstedtii in previous studies. The 20 genes showed potential to enhance the methods for the identification and epidemiological investigation of CKC.
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Infecciones por Corynebacterium , Mastitis , Femenino , Humanos , Infecciones por Corynebacterium/complicaciones , Infecciones por Corynebacterium/microbiología , Filogenia , ARN Ribosómico 16S/genética , Corynebacterium/genética , Mastitis/complicaciones , GenómicaRESUMEN
The rates of many electrocatalytic reactions can be strongly affected by the structure and dynamics of the electrochemical double layer, which in turn can be tuned by the concentration and identity of the supporting electrolyte's cation. The effect of cations on an electrocatalytic process depends on a complex interplay between electrolyte components, electrode material and surface structure, applied electrode potential, and reaction intermediates. Although cation effects remain insufficiently understood, the principal mechanisms underlying cation-dependent reactivity and selectivity are beginning to emerge. In this Perspective, we summarize and critically examine recent advances in this area in the context of the hydrogen evolution reaction (HER) and CO2-to-CO conversion, which are among the most intensively studied and promising electrocatalytic reactions for the sustainable production of commodity chemicals and fuels. Improving the kinetics of the HER in base and enabling energetically efficient and selective CO2 reduction at low pH are key challenges in electrocatalysis. The physical insights from the recent literature illustrate how cation effects can be utilized to help achieve these goals and to steer other electrocatalytic processes of technological relevance.
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OBJECTIVES: Anesthetic agents used during deep brain stimulation (DBS) surgery might interfere with microelectrode recording (MER) and local field potential (LFP) and thus affect the accuracy of surgical target localization. This review aimed to identify the effects of different anesthetic agents on neuronal activity of the subthalamic nucleus (STN) during the MER procedure. MATERIALS AND METHODS: We used Medical Subject Heading terms to search the PubMed, EMBASE, EBSCO, and ScienceDirect data bases. MER characteristics were sorted into quantitative and qualitative data types. Quantitative data included the burst index, pause index, firing rate (FR), and interspike interval. Qualitative data included background activity, burst discharge (BD), and anesthetic agent effect. We also categorized the reviewed manuscripts into those describing local anesthesia with sedation (LAWS) and those describing general anesthesia (GA) and compiled the effects of anesthetic agents on MER and LFP characteristics. RESULTS: In total, 26 studies on MER were identified, of which 12 used LAWS and 14 used GA. Three studies on LFP also were identified. We found that the FR was preserved under LAWS but tended to be lower under GA, and BD was reduced in both groups. Individually, propofol enhanced BD but was better used for sedation, or the dosage should be minimized in GA. Similarly, low-dose dexmedetomidine sedation did not disturb MER. Opioids could be used as adjunctive anesthetic agents. Volatile anesthesia had the least adverse effect on MER under GA, with minimal alveolar concentration at 0.5. Dexmedetomidine anesthesia did not affect LFP, whereas propofol interfered with the power of LFP. CONCLUSIONS: The effects of the tested anesthetics on the STN in MER and LFP of Parkinson's disease varied; however, identifying the STN and achieving a good clinical outcome are possible under controlled anesthetic conditions. For patient comfort, anesthesia should be considered in STN-DBS.
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BACKGROUND: Phenolic endocrine-disrupting chemicals (EDCs) are widespread and easily ingested through the food chain. They pose a serious threat to human health. Magnetic solid-phase extraction (MSPE) is an effective sample pre-treatment technology to determine traces of phenolic EDCs. RESULTS: Magnetic covalent organic framework (COF) (Fe3 O4 @COF) nanospheres were prepared and characterized. The efficient and selective extraction of phenolic EDCs relies on a large specific surface and the inherent porosity of COFs and hydrogen bonding, π-π, and hydrophobic interactions between COF shells and phenolic EDCs. Under optimal conditions, the proposed magnetic solid-phase extraction-high-performance liquid chromatography-ultra violet (MSPE-HPLC-UV) based on the metallic covalent organic framework method for phenolic EDCs shows good linearities (0.002-6 µg mL-1 ), with R2 of 0.995 or higher, and low limits of detection (6-1.200 ng mL-1 ). CONCLUSION: Magnetic covalent organic frameworks (Fe3 O4 @COFs) with good MSPE performance for phenolic EDCs were synthesized by the solvothermal method. The magnetic covalent organic framework-based MSPE-HPLC-UV method was applied successfully to determine phenolic EDCs in beverage and water samples with satisfactory recoveries (90.200%-123%) and relative standard deviations (2.100%-12.100%). © 2023 Society of Chemical Industry.
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Disruptores Endocrinos , Estructuras Metalorgánicas , Humanos , Estructuras Metalorgánicas/química , Cromatografía Líquida de Alta Presión , Bebidas , Extracción en Fase Sólida/métodos , Fenoles , Fenómenos Magnéticos , Agua/química , Límite de DetecciónRESUMEN
Colloidal chemistry holds promise to prepare uniform and size-controllable pre-catalysts; however, it remains a challenge to unveil the atomic-level transition from pre-catalysts to active catalytic surfaces under the reaction conditions to enable the mechanistic design of catalysts. Here, we report an ambient-pressure X-ray photoelectron spectroscopy study, coupled with in situ environmental transmission electron microscopy, infrared spectroscopy, and theoretical calculations, to elucidate the surface catalytic sites of colloidal Ni nanoparticles for CO2 hydrogenation. We show that Ni nanoparticles with phosphine ligands exhibit a distinct surface evolution compared with amine-capped ones, owing to the diffusion of P under oxidative (air) or reductive (CO2 + H2) gaseous environments at elevated temperatures. The resulting NiPx surface leads to a substantially improved selectivity for CO production, in contrast to the metallic Ni, which favors CH4. The further elimination of surface metallic Ni sites by designing multi-step P incorporation achieves unit selectivity of CO in high-rate CO2 hydrogenation.
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BACKGROUND: In the nasal cavity, nitric oxide (NO) is involved in many physiological functions, including antibacterial and antiviral activity, promotion of nasal mucociliary clearance, and regulation of blood vessel expansion in the nasal mucosa. We investigated the distribution of NO concentration in the nasal cavity of healthy individuals during breathing. METHODS: A three-dimensional numerical model of the nasal airway, including the bilateral maxillary sinuses, was created to simulate NO distribution in the nasal cavity during normal breathing. The effect of different nasal airflow velocities and NO concentrations in the maxillary sinus on NO distribution in the nasal cavity was evaluated. The NO concentration in the nasal exhalation of 50 healthy people in Dalian was measured using an NO analyzer, and the growth rate of the NO concentration in the nasal cavity was measured under breath-holding conditions. RESULTS: The distribution of NO concentration in the nasal cavity of healthy people during breathing was obtained from numerical simulation results. Lower the airflow rate, higher was the NO concentration and greater was the diffusion range in the nasal cavity. The NO concentration in the nasal cavity increased with an increase in its concentration in the maxillary sinus, indicating a linear relationship. The NO concentration in the nasal exhalation of healthy people in Dalian and the growth rate of the NO concentration in the nasal cavity under breath-holding conditions were obtained through experiments. The numerical results correspond with the experimental results. CONCLUSIONS: The NO entered the nasal cavity mainly by diffusion and followed the convection flow of the respiratory air in the nasal cavity. NO concentration in the nasal cavity was related to the respiratory airflow velocity and NO concentration in the maxillary sinus. During inspiration, NO was present only in the nasal airway posterior to the maxillary sinus ostium, whereas during exhalation, the exhaled NO diffusely distributed throughout the nasal cavity.
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Cavidad Nasal , Óxido Nítrico , Humanos , Cavidad Nasal/fisiología , Respiración , Seno Maxilar/fisiología , Espiración/fisiologíaRESUMEN
OBJECTIVES: To evaluate the identification of tumor deposits (TDs) and the prognostic significance of an MRI tumor regression grade for TDs in patients with rectal cancer treated with neoadjuvant chemoradiotherapy (nCRT). METHODS: Ninety-one patients with cT3 or cT4 rectal cancer who underwent surgery following nCRT between August 2014 and June 2020 were retrospectively analyzed. Changes in pre-nCRT MRI-detected TDs (mrTDs) were described as mrTD regression grade. The diagnostic performance of post-nCRT MRI-detected TDs (ymrTDs) was compared with histopathological reference standard. The correlation between ymrTDs, mrTD regression grade, and disease-free survival (DFS) was assessed. RESULTS: The sensitivity and specificity of ymrTDs were 88.00% and 89.39%, respectively. The area under the receiver operating characteristic curve was 0.887 (95% confidence interval [CI]: 0.803-0.944). The 3-year DFS of patients with positive ymrTDs was significantly lower than of the negative group (44.83% vs 82.73%, p < 0.001). The 3-year DFS was 33.33% for patients with poor regression of mrTDs following nCRT and 55.56% for those with moderate regression, compared to 69.23% in good responders and 83.97% in patients without mrTDs (p < 0.001). On multivariable Cox regression, mrTD regression grade was the only independent MRI factor associated with DFS (p = 0.042). CONCLUSIONS: Diagnostic performance of ymrTDs was moderate. The mrTD regression grade was independently correlated with DFS, which may have a prognostic implication for treatment and follow-up. CLINICAL RELEVANCE STATEMENT: Patients with poor regression of MRI-detected tumor deposits may benefit from more aggressive treatments, such as chemoradiation therapy plus induction or consolidation chemotherapy. KEY POINTS: ⢠MRI provides a preoperative and noninvasive way to visualize tumor deposits (TDs) after neoadjuvant chemoradiotherapy (nCRT). ⢠Post-nCRT MRI-detected TDs are a poor prognostic marker in cT3 and cT4 rectal cancer patients. ⢠The regression of MRI-detected TDs after nCRT is associated with an improved disease-free survival.
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Water usage increased alongside its competitiveness due to its finite amount. Yet, many industries still rely on this finite resource thus recalling the need to recirculate their water for production. Circular bioeconomy is presently the new approach emphasizing on the 'end-of-life' concept with reusing, recycling, and recovering materials. Microalgae are the ideal source contributing to circular bioeconomy as it exhibits fast growth and adaptability supported by biological rigidity which in turn consumes nutrients, making it an ideal and capable bioremediating agent, therefore allowing water re-use as well as its biomass potential in biorefineries. Nevertheless, there are challenges that still need to be addressed with consideration of recent advances in cultivating microalgae in wastewater. This review aimed to investigate the potential of microalgae biomass cultivated in wastewater. More importantly, how it'll play a role in the circular bioeconomy. This includes an in-depth look at the production of goods coming from wastes tattered by emerging pollutants. These emerging pollutants include microplastics, antibiotics, ever-increasingly sewage water, and heavy metals which have not been comprehensively compared and explored. Therefore, this review is aiming to bring new insights to researchers and industrial stakeholders with interest in green alternatives to eventually contribute towards environmental sustainability.
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Contaminantes Ambientales , Microalgas , Aguas Residuales , Biodegradación Ambiental , Plásticos , Biomasa , BiocombustiblesRESUMEN
With rapid growing world population and increasing demand for natural resources, the production of sufficient food, feed for protein and fat sources and sustainable energy presents a food insecurity challenge globally. Insect biorefinery is a concept of using insect as a tool to convert biomass waste into energy and other beneficial products with concomitant remediation of the organic components. The exploitation of insects and its bioproducts have becoming more popular in recent years. This review article presents a summary of the current trend of insect-based industry and the potential organic wastes for insect bioconversion and biorefinery. Numerous biotechnological products obtained from insect biorefinery such as biofertilizer, animal feeds, edible foods, biopolymer, bioenzymes and biodiesel are discussed in the subsequent sections. Insect biorefinery serves as a promising sustainable approach for waste management while producing valuable bioproducts feasible to achieve circular bioeconomy.
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Alimentos , Administración de Residuos , Animales , Insectos , Industrias , Biocombustibles , BiomasaRESUMEN
Unnecessary radiation exposure (URE) during radiographic examination is an issue among infants in neonatal intensive care units (NICUs). The causes of URE have not been fully explored. This study investigated the incidence and identified the causes of URE in infants during diagnostic radiography in a NICU. This was a retrospective cohort study. We retrieved and analysed requests and radiographs taken at a tertiary NICU between September and November 2018. URE was defined as the rate of discordance between requests and images taken (DisBRI) and unnecessary radiation exposure in irrelevant regions (UREIR) during radiography. We compared the rates of URE between very low-birth-weight (VLBW, birth weight < 1500 g) infants and non-VLBW infants. A total of 306 radiographs from 88 infants were taken. The means ± standard deviations (SDs) of gestational age and birth weight were 35.7 ± 3.6 weeks and 2471 ± 816 g, respectively. Each infant underwent an average of 3.5 radiographs. The DisBRI rate was 1.3% and was mostly related to poor adherence to requests. The UREIR rates in thoraco-abdominal babygrams were 89.6% for the head, 14.8% for the elbows and 18.4% for the knee and were mainly related to improper positioning of and collimation in infants while performing radiography. The UREIR rates for the head, knee and ankle were higher in VLBW infants than in non-VLBW infants (94.6% vs. 85.6%, 27.0% vs. 11.5% and 5.4% vs. 0.7%, respectively, p < 0.05). CONCLUSIONS: URE during diagnostic radiography is common in sick infants and is mainly related to improper positioning and collimation during examinations. Adherence to protocols when performing radiographic examination or using ultrasonography may be a solution to reduce URE in infants in NICUs. WHAT IS KNOWN: ⢠The risk of unnecessary radiation exposure (URE) during radiography has been a common and important issue in sick infants in neonatal intensive care units (NICUs). ⢠The new point-of-care ultrasound (POCUS) technique decreases the need for chest films and prevents radiation exposure in neonates. WHAT IS NEW: ⢠In the NICU, URE is still a common issue in critically ill infants during radiographic examinations. The causes of URE during diagnostic radiography are mainly due to improper positioning and collimation during examinations. ⢠The incidence of URE in irrelevant regions is higher in very low-birth-weight (VLBW) infants than in non-VLBW infants.
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Unidades de Cuidado Intensivo Neonatal , Exposición a la Radiación , Recién Nacido , Lactante , Humanos , Peso al Nacer , Estudios Retrospectivos , Recién Nacido de muy Bajo Peso , Radiografía , Exposición a la Radiación/efectos adversosRESUMEN
The latest clinical trials have reported conflicting outcomes regarding the effectiveness of xenon anesthesia in preventing postoperative neurocognitive dysfunction; thus, this study assessed the existing evidence. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases from inception to April 9, 2023, for randomized controlled trials of xenon anesthesia in postoperative patients. We included English-language randomized controlled studies of adult patients undergoing surgery with xenon anesthesia that compared its effects to those of other anesthetics. Duplicate studies, pediatric studies, and ongoing clinical trials were excluded. Nine studies with 754 participants were identified. A forest plot revealed that the incidence of postoperative neurocognitive dysfunction did not differ between the xenon anesthesia and control groups (P = 0.43). Additionally, xenon anesthesia significantly shortened the emergence time for time to opening eyes (P < 0.001), time to extubation (P < 0.001), time to react on demand (P = 0.01), and time to time and spatial orientation (P = 0.04). However, the Aldrete score significantly increased with xenon anesthesia (P = 0.005). Postoperative complications did not differ between the anesthesia groups. Egger's test for bias showed no small-study effect, and a trim-and-fill analysis showed no apparent publication bias. In conclusion, xenon anesthesia probably did not affect the occurrence of postoperative neurocognitive dysfunction. However, xenon anesthesia may effectively shorten the emergence time of certain parameters without adverse effects.
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Anestésicos , Delirio , Adulto , Humanos , Niño , Xenón/farmacología , Periodo Posoperatorio , Anestesia por Inhalación/efectos adversos , Delirio/inducido químicamenteRESUMEN
A hybrid catalyst with integrated single-atom Ni and nanoscale Cu catalytic components is reported to enhance the C-C coupling and ethylene (C2H4) production efficiency in the electrocatalytic CO2 reduction reaction (eCO2RR). The single-atom Ni anchored on high-surface-area ordered mesoporous carbon enables high-rate and selective conversion of CO2 to CO in a wide potential range, which complements the subsequent CO enrichment on Cu nanowires (NWs) for the C-C coupling to C2H4. In situ surface-enhanced infrared absorption spectroscopy (SEIRAS) confirms the substantially improved CO enrichment on Cu, once the incorporation of single-atom Ni occurs. Also, in situ X-ray absorption near-edge structure (XANES) demonstrates the structural stability of the hybrid catalyst during eCO2RR. By modulating hybrid compositions, the optimized catalyst shows 66% Faradaic efficiency (FE) in an alkaline flow cell with over 100 mA·cm-2 at -0.5 V versus reversible hydrogen electrode, leading to a five-order enhancement in C2H4 selectivity compared with single-component Cu NWs.
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Riboswitches are RNA molecules that can regulate gene expression which is affected by ligand-binding during cotranscriptional folding process. However, the role of ligand during the folding is still unclear. In this study, the pfl domain of Thermosinus carboxydivorans ZTP riboswitch was discussed. The ligand is molecule ZMP. We mainly analyzed the change of ZMP-free and ZMP-bound aptamer domain by the dynamics simulation method. Structural features by calculating their RMSD, RMSF, etc. are analyzed. The results demonstrate that the binding domain require the presence of ZMP to maintain a stable fold. It also suggested that ZMP specificly binding to ZTP can generate more hydrogen bonds in the binding domain. Through the calculation of binding free energy decomposition of each nucleotide, molecule ZMP was found to promote the recognition and binding process of ligands by controlling some special nucleotides in the process of ligand binding. At last, the dynamical correlation and components of conformational motions were both applied to explore the effect of molecule ZMP to ZTP riboswitch. In general, ZMP can effectively affect the motions of the pfl riboswitch and facilitate the folding process of the ZTP riboswitch.These results may provide some new ideas for structural changes in riboswitches and their cotranscriptional folding process.
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Aptámeros de Nucleótidos , Riboswitch , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/genética , Firmicutes/genética , Ligandos , Simulación de Dinámica Molecular , Conformación de Ácido NucleicoRESUMEN
BACKGROUND: Respiratory failure is one of the most common complications following cardiac surgery. Although noninvasive ventilation (NIV) has been an effective treatment, it has a high rate of intolerance. Both remifentanil and dexmedetomidine are used as sedatives in cardiac surgery (CS) patients with NIV intolerance. However, no randomized controlled trials have compared the effects of these drugs in relieving the intolerance. METHODS: REDNIVI will be a multicenter, prospective, single-blind, randomized controlled trial carried out in six clinical sites in China. Subjects with NIV intolerance will be randomized to receive remifentanil or dexmedetomidine in a ratio of 1:1. Primary outcomes of intolerance remission rate at different timings (15 minutes, 1, 3, 6, 12, 24, 36, 48, 60, 72 hours after initiation of treatment) and 72 h average remission rate will be determined. In addition, secondary outcomes such as mortality, duration of intensive care unit (ICU) stay, duration of mechanical ventilation (MV), the need for endotracheal intubation, hemodynamic changes, and delirium incidence will also be determined. CONCLUSIONS: This trial will provide evidence to determine the effects of remifentanil and dexmedetomidine in patients with NIV intolerance after cardiac surgery. CLINICAL TRIAL REGISTRATION: This study has been registered on ClinicalTrials.gov (NCT04734418).
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Procedimientos Quirúrgicos Cardíacos , Dexmedetomidina , Ventilación no Invasiva , Remifentanilo , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Dexmedetomidina/uso terapéutico , Humanos , Estudios Multicéntricos como Asunto , Ventilación no Invasiva/efectos adversos , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Remifentanilo/uso terapéutico , Método Simple CiegoRESUMEN
BACKGROUND: Quantitative computed tomography (QCT) analysis may serve as a tool for assessing the severity of coronavirus disease 2019 (COVID-19) and for monitoring its progress. The present study aimed to assess the association between steroid therapy and quantitative CT parameters in a longitudinal cohort with COVID-19. METHODS: Between February 7 and February 17, 2020, 72 patients with severe COVID-19 were retrospectively enrolled. All 300 chest CT scans from these patients were collected and classified into five stages according to the interval between hospital admission and follow-up CT scans: Stage 1 (at admission); Stage 2 (3-7 days); Stage 3 (8-14 days); Stage 4 (15-21 days); and Stage 5 (22-31 days). QCT was performed using a threshold-based quantitative analysis to segment the lung according to different Hounsfield unit (HU) intervals. The primary outcomes were changes in percentage of compromised lung volume (%CL, - 500 to 100 HU) at different stages. Multivariate Generalized Estimating Equations were performed after adjusting for potential confounders. RESULTS: Of 72 patients, 31 patients (43.1%) received steroid therapy. Steroid therapy was associated with a decrease in %CL (- 3.27% [95% CI, - 5.86 to - 0.68, P = 0.01]) after adjusting for duration and baseline %CL. Associations between steroid therapy and changes in %CL varied between different stages or baseline %CL (all interactions, P < 0.01). Steroid therapy was associated with decrease in %CL after stage 3 (all P < 0.05), but not at stage 2. Similarly, steroid therapy was associated with a more significant decrease in %CL in the high CL group (P < 0.05), but not in the low CL group. CONCLUSIONS: Steroid administration was independently associated with a decrease in %CL, with interaction by duration or disease severity in a longitudinal cohort. The quantitative CT parameters, particularly compromised lung volume, may provide a useful tool to monitor COVID-19 progression during the treatment process. Trial registration Clinicaltrials.gov, NCT04953247. Registered July 7, 2021, https://clinicaltrials.gov/ct2/show/NCT04953247.
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Tratamiento Farmacológico de COVID-19 , Humanos , Pulmón/diagnóstico por imagen , Mediciones del Volumen Pulmonar/métodos , Estudios Retrospectivos , Esteroides/uso terapéuticoRESUMEN
PURPOSE: To investigate the safety of replacing doxorubicin with tirapazamine in conventional transarterial chemoembolization (TACE) in an Asian population with hepatocellular carcinoma (HCC), and to determine the optimal tirapazamine dose for phase II studies. MATERIALS AND METHODS: This was a phase I, 3 + 3 dose-escalation study for patients with unresectable early- and intermediate-stage HCC who received 5, 10, or 20 mg/m2 of intra-arterial (IA) tirapazamine followed by ethiodized oil/gelatin sponge-based embolization. Key eligibilities included HCCs no more than 10 cm in diameter, prior embolization allowed, Eastern Cooperative Oncology Group performance status of 0 or 1, Child-Pugh score of 5-7, and platelet count of ≥60,000 µL. Dose-limiting toxicity (DLT) was defined as any grade 3 nonhematological or grade 4 hematological toxicity, with the exception of transient elevation of aminotransferase levels after the procedure. RESULTS: Seventeen patients were enrolled, 59% of whom had progression from a prior HCC therapy and 35% of whom had progression or recurrence after TACE. All patients tolerated the tirapazamine TACE well without any DLT or serious adverse event. Using the modified Response Evaluation Criteria in Solid Tumors, the complete response (CR) rate was 47%, and the CR + partial response rate was 65%. The median duration of response was not reached. The median time to progression was 12.6 months (95% confidence interval, 5.1-not reached). The median overall survival was 29.3 months. The selected phase II dose was set at a fixed dose of 35 mg of IA tirapazamine. CONCLUSIONS: IA tirapazamine with transarterial embolization was well tolerated and showed promising efficacy signals in intermediate-stage HCC, justifying pursuit of a phase II study.