Engineering of surface-modified CuBTC-MXene nanocarrier for adsorption and co-loading of curcumin/paclitaxel from aqueous solutions for synergistic multi-therapy of cancer

Two-dimensional (2D) nanomaterials can improve drug delivery by reducing toxicity, increasing bioavailability and boosting efficacy. In this study, the simultaneous use of transition metal carbides and nitrides (MXenes) along with copper (II) benzene-1, 3, 5-tricarboxylate metal-organic framework (Cu - BTC/MOF) as attractive nanocarriers are investigated for loading and delivering curcumin (CUR) and paclitaxel (PTX) drugs to cancer cells. The efficiency of surface termination (bare and oxygen) in the adsorption of PTX and CUR drugs and the co-loading of these two drugs are evaluated. Our results show that the strongest interaction energy belongs to the adsorption of drug CUR on the MXNNO-Cu-BTC adsorbent, while the interaction of PTX drug with the MXNO- Cu-BTC in the MXNO-Cu-BTC/PTX&CUR system is the lowest due to the particular structure of the drug and the adsorbent. Our results show that at the beginning simulation, the interaction energy between the PTX drug and water in PTX/MXN system is -4645.48 kJ/mol, which reduces to -3848.71 kJ/mol after the system reaches equilibrium. Therefore, the inspected adsorbents have a good performance in adsorbing CUR and PTX drugs. The obtained results from this investigation provide valuable information about experimental studies by medical scientists in the future.Communicated by Ramaswamy H. Sarma.

Adsorption Efficiency of Carbon Materials for the Removal of Organic Pollutants: DDT from Aqueous Solution

Carbon nanotubes (CNTs) are widely used to adsorb organic pollutants from wastewater due to their porous structure, large specific surface area, and unique physical and chemical properties. Examining the interactions between pollutant molecules and carbon nanotubes is an important topic in the applications of nanotubes for the removal of pollutants. In this study, molecular dynamics (MD) and metadynamics simulations were used to investigate the adsorption mechanism of Dichlorodiphenyltrichloroethane (DDT) pollutants on carbon nanotubes. Obtained results revealed that functionalized CNTs (f-CNTs) with active groups exhibited significantly enhanced performance compared to pristine CNTs. The adsorption isotherms were analyzed at different DDT concentrations, and it was found that increasing the concentration of DDT molecules led to a decrease in system energy and increased stability. The presence of biosurfactants as functional groups on the CNTs enhanced the interaction between DDT molecules and the nanotubes. In CNT, the addition of DDT increases the van der Waals energy from -176.83 kJ/mol for 3 DDT molecules to -2237.88 kJ/mol for 50 DDT molecules. In the case of f-CNT, the van der Waals energy in the system with 50 DDT molecules is about 2061.05 kJ/mol more negative than the system with 3 DDT molecules. The number of contacts between the adsorbent and DDT molecules increased over time, indicating increased adsorption interaction. The radial distribution functions (RDF) of DDT molecules around CNTs and f-CNTs showed the highest probability of finding DDT molecules at a distance of about 0.5 nm from the adsorbent surface. The study provided valuable insights into the adsorption process and can guide future experimental studies.

Toward efficient electrodes for a high-performance fast-charge Li-ion battery: molecular dynamics simulation and DFT calculations

Due to the increasing demand for electrochemical energy storage, rechargeable lithium-ion batteries (LIBs) are gaining more and more attention. However, much research still needs to be conducted to enhance their cycling and storage capacity. Recently, computational studies have provided valuable information for LIB development, which is very difficult and expensive to obtain experimentally. In this study, molecular dynamics (MD) simulation and first-principles calculations are performed to investigate the potential of a Cu-BHT MOF and phosphorene as the cathode and anode, respectively. An external electrical field is applied to simulate the charging process and study lithium-ion behavior during migration from the cathode to the anode in an electrolyte. Time and space-dependent variables such as energy, radial distribution function, mean square displacement (MSD), density, and so on have been used to evaluate the studied system. The MSD calculations showed that there are two different regimes in the MSD curves of Li-ions; diffusion and cage. In the designed LIB, the cathode has a better performance in the presence of a high electric field, whereas under an external electric field of 1.5 V Å-1, more lithium ions move from the cathode to the anode. By using first-principles calculations the lithium insertion in phosphorene and Cu-BHT is studied in various configurations and concentrations. The obtained results indicated that the adsorption energy of lithium on the cathode in the most stable configuration is -3.21 eV which is enough to prevent the clustering effect. Furthermore, the interaction of Li with phosphorene is strong enough and forms a stable complex. It is found that by insertion of Li into the anode the band gap is decreased which indicates the possibility of fast charging of LIBs. Investigation of different concentrations of ions reveals that the Li-Li repulsive interactions lead to a decrease in the adsorption energy of Li with the anode and cathode. The results of this study provide an in-depth insight into LIBs.

State-of-the-art predictive modeling of heavy metal ions removal from the water environment using nanotubes

In this research, molecular dynamics (MD) simulation is used to investigate the efficiency of carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) in removing lead ions from contaminated waters. Then the effect of functionalizing nanotubes with -COO- and COOH- functional groups and the nanotubes' absorption performance of two different concentrations of lead ions are studied. To better evaluate adsorption process, the set of descriptors, such as interaction energies, radial distribution function, etc., are calculated. The MD results show that the absorption performance is significantly improved by modifying the surface of CNT and BNNT with functional groups. In addition, the adsorption capacity increases in higher concentrations of Pb ions at BNNTCOO- and CNTCOOH systems. The interaction energy of BNNTCOO- with a concentration of 50 lead ions is - 2879.28 kJ/mol, which is about 106 kJ/mol more negative than BNNTCOO- at a concentration of 20 lead ions. Also, it is observed that the functionalization of both nanotubes with -COO- increases their absorption capacity. The obtained results from this study provide significant information about the mechanisms of lead adsorption on the surface of nanotubes.

Graphene Oxide Hosting a pH-Sensitive Prodrug: An In Silico Investigation of Graphene Oxide-Based Nanovehicle toward Cancer Therapy

Prodrug and drug delivery systems are two effective strategies for improving the selectivity of chemotherapeutics. Herein, via molecular dynamics (MD) simulation and free energy calculation, the effectiveness of the graphene oxide (GO) decorated with the pH-sensitive prodrug (PD) molecules in cancer therapy is investigated. PEI-CA-DOX (prodrug) was loaded onto the GO surface, in which the hydrogen bonding and pi-pi stacking interactions play the main role in the stability of the GO-PD complex. Due to the strong interaction of GO and PD (about -800 kJ/mol), the GO-PD complex remains stable during the membrane penetration process. The obtained results confirm that GO is a suitable surface for hosting the prodrug and passing it through the membrane. Furthermore, the investigation of the release process shows that the PD can be released under acidic conditions. This phenomenon is due to the reduction of the contribution of electrostatic energy in the GO and PD interaction and the entry of water into the drug delivery system. Moreover, it is found that an external electrical field does not have much effect on drug release. Our results provide a deep understanding of the prodrug delivery systems, which helps the combination of nanocarriers and modified chemotherapy drugs in the future.

Can triage correctly stratify cardiogenic syncope in patients admitted to the emergency department for a transitory loss of consciousness?

Background

The Manchester Triage System (MTS) is the most popular validated triage system in Europe. It allows the stratification of the large volume of patients admitted to the emergency department (ED) into five increasing risk categories, assigning higher priority to the most serious patients [1].

Purpose

To evaluate the effectiveness of the MTS in stratifying patients admitted to the ED for syncopal transitory loss of consciousness (TLOC) and correctly identifying cardiogenic syncope.

Methods

All patients consecutively evaluated in the ED between 1 January 2017 and 1 July 2019 for a TLOC episode were retrospectively considered. TLOCs were retrospectively classified according to the guidelines of the European Society of Cardiology (ESC) [2]. Syncopal TLOCs were separated from non-syncopal TLOCs. Demographic and baseline characteristics of all patients were recorded. Patients were divided into two groups for comparison according to the MTS code assigned at triage: blue/green/yellow (low priority) versus orange/red (high priority). Considering only syncopal TLOCs, the primary study outcome was the presence of cardiogenic syncope as defined in the ESC guidelines. The performance of the MTS was evaluated using a 2x2 table, deriving sensitivity, specificity and accuracy, and through analysing receiver operating characteristic curves. Sensitivity analyses were also performed on patient subgroups.

Results

A total of 2,291 patients with TLOC were considered (83% low priority versus 17% high priority). Of these, 90.2% (2,066/2,291) presented syncopal TLOC. Among the patients with syncopal TLOC, 85.7% (1,770/2,066) were assigned a low priority code, while 14.3% (296/2,066) were given high priority. Patients with a high priority code were older (median age 66 versus 77 years; p<0.001), presented more altered vital signs (p<0.001), presented more associated symptoms (p<0.001) and presented more cardiac comorbidities (p<0.001).

Overall, cardiogenic syncope was present in 7.5% (154/2,066) of patients with syncopal TLOC. Of these, 55.2% (85/154) were stratified with a low priority code, while 44.8% (69/154) were stratified with a high priority code (p<0.001). The MTS presented a sensitivity of 44.8%, a specificity of 88.1% and an accuracy of 84.9%. The area under the receiver operating characteristic curve for the prioritisation of cardiogenic syncope through MTS codes was 0.683. Sensitivity analyses on specific subgroups of patients, such as those with or without other associated symptoms in triage or major cardiac comorbidities, revealed comparable performance.

Conclusions

Syncopal TLOC is an insidious clinical condition. Currently, limited information is available about triage systems and the correct prioritisation of syncope.

Although the MTS has demonstrated good performance for other cardiac symptoms, its performance is not acceptable for syncopal TLOC [3]. Improvements are needed to optimise triage systems for syncopal TLOC.

Funding Acknowledgement

Type of funding sources: None.

The use of ECG by triage nurses may improve the stratification of patients with cardiological symptoms admitted to the emergency department: a prospective observational study

Background

Triage is the crucial point for overall emergency department (ED) management. Its purpose is to quickly and safely identify among the many patients arriving those who need rapid medical evaluation [1]. Present triage systems are based on symptomatic assessment and clinical impression to assess patient severity on admission to the ED. Some clinical tools that are widely validated in practice, such as ECG, could be implemented in triage to improve the stratification activity of the system [2].

Purpose

To evaluate whether the use of ECG can improve nursing triage prediction for patients admitted to the ED for symptoms related to suspected cardiac pathology.

Methods

A prospective observational single-centered study was conducted. All patients who visited the ED for chest pain, syncope, dyspnoea or palpitation and underwent ECG at the time of triage were considered. The study was conducted by a pool of nurses who had previously received special training in ECG reading. Background characteristics, comorbidities and clinical conditions were recorded for each enrolled patient. In addition, the priority level assigned according to the application of the 5-level Manchester Triage System (1 to 5) and the level of priority after ECG performance (1 to 5) were recorded. The study outcome was composite: the presence of a major cardiac event within 6 weeks after triage, a cardiogenic syncope, the presence of a pulmonary embolism or aortic dissection, or an arrhythmia requiring specific emergency therapy [3]. The priority level assigned in triage and the priority level given after performing the ECG were compared by analysis of the receiver operating characteristic.

Results

A total of 1,211 patients were included in the study. Of these, 62.4% (756/1,211) presented chest pain, 13.8% (167/1,211) syncope, 18.2% (221/1,211) palpitation and 5.5% (67/1,211) dyspnoea. Overall, 10.5% (127/1,211) had a positive outcome. The concordance between triage nurses and cardiologists in detecting pathological and non-pathological ECGs presented a Cohen's kappa of 0.821 (p<0.001). ECG performed by nurses increased the patient's priority in 7.5% (91/1,211) of cases and reduced it in 39.6% (480/1,211) of cases. The discriminatory ability of the triage system before ECG was performed showed an area under the receiver operating characteristic curve of 0.708 (95% CI 0.659–0.757), whereas the discriminatory ability of triage after ECG was 0.845 (95% CI 0.808–0.883).

Conclusions

The use of ECG in triage can be a simple and safe tool that improves the assessment of the patient's priority when presenting to the ED for a cardiac symptom. The presence of a good diagnostic concordance and a good improvement in discriminatory ability may support the implementation of ECG in nursing triage.

Funding Acknowledgement

Type of funding sources: None.

Molecular interpretation of the carbon nitride performance as a template for the transport of anti-cancer drug into the biological membrane

Evaluation of interaction mechanism between 2-dimensional (2D) nanomaterials and cell membranes is a critical issue in providing guidelines for biomedical applications. Recent progress in computer-aided molecular design tools, especially molecular dynamics (MD) simulation, afford a cost-effective approach to achieving this goal. In this work, based on this hypothesis, by utilizing theoretical methods including MD simulation and free energy calculations, a process is evaluated in which the Doxorubicin (DOX)-loaded onto carbon nitride (CN) nanosheet faced with bilayer membrane. It should be mentioned that to achieve an efficient CN-based drug delivery system (DDS), in the first place, the intermolecular interaction between the carrier and DOX is investigated. The obtained results show that the DOX prefers a parallel orientation with respect to the CN surface via the formation of π-π stacking and H-bond interactions. Furthermore, the adsorption energy value between the drug and the carrier is evaluated at about - 312 kJ/mol. Moreover, the investigation of the interaction between the CN-DOX complex and the membrane reveals that due to the presence of polar heads in the lipid bilayer, the contribution of electrostatic energy is higher than the van der Waals energy. The global minimum in free energy surface of the DDS is located between the head groups of the cell membrane. Overall, it can be concluded that the CN nanosheet is a suitable candidate for transfer and stabilize DOX on the membrane.

[Risk stratification nomogram for COVID-19 patients with interstitial pneumonia in the emergency department : A retrospective multicenter study]

Hintergrund

Es gibt zurzeit noch keine zuverlässige Methode zur Früherkennung von COVID-19-Patienten in der Notaufnahme, deren Krankheitsverlauf sich rapide verschlechtern und zum Tod führen kann.

Ziel

Das Ziel dieser Arbeit ist die Untersuchung prädiktiver Risikofaktoren für die 30-Tage-Mortalität bei COVID-19-Patienten mit interstitieller Pneumonie anhand anamnestischer, klinischer und labortechnischer Parameter und die Entwicklung eines Nomogramms zur Risikostratifizierung in der Notaufnahme.

Methode

In den Notaufnahmen der Krankenhäuser von Meran und Brixen wurde im Zeitraum vom 01. März 2020 bis zum 31. März 2020 eine retrospektive multizentrische Studie an einer Kohorte von 164 Patienten mit COVID-19-Pneumonie durchgeführt. Die Patienten wurde mittels Fluoreszenz-Reverse-Transkriptions-Polymerasekettenreaktion (RT-PCR) positiv auf SARS-CoV‑2 getestet. Anhand der untersuchten Parameter wurde ein Nomogramm zur Risikostratifizierung der 30-Tage-Mortalität von COVID-19-Patienten entwickelt.

Ergebnisse

35 (21,3 %) der 164 COVID-19-Patienten mit interstitieller Pneumonie verstarben innerhalb von 30 Tagen nach Aufnahme in die Notaufnahme. Die multivariate Analysemethode ergab, dass kognitive Veränderungen (OR: 8,330; p = 0,004), Lymphozytopenie (OR: 4,229; p = 0,049), Veränderung der Nierenfunktion (OR: 4,841; p = 0,028), periphere Sauerstoffsättigung < 93 % (OR: 17,871; p = 0,002), Alter > 75 Jahre (OR: 2,925; p = 0,032), erhöhtes C‑reaktives Protein (OR: 6,504; p = 0,005), niedrige Monozytenwerte (OR: 0,504; p = 0,004) und Komorbidität (OR 5,862; p = 0,019) mit der 30-Tage-Mortalität assoziiert waren. Anhand dieser 8 Parameter wurde ein Nomogramm entwickelt, das eine gute Diskriminierung mit einer Fläche unter der ROC-Kurve von 0,937 ergab.

Schlussfolgerung

Die erste Auswertung der in der Notaufnahme erhobenen anamnestischen, klinischen und labortechnischen Daten liefert wichtige prognostische Informationen für die Risikostratifizierung von COVID-19-Patienten in der Notaufnahme und für die Früherkennung von kritischen Verläufen.