Validation of a method for estimating pulmonary dead space in ventilated beagles to correct exhaled propofol concentration in mixed air.

Background: Mixed exhaled air has been widely used to determine exhaled propofol concentrations with online analyzers, but changes in dead space proportions may lead to inaccurate assessments of critical drug concentration data. This study proposes a method to correct propofol concentration in mixed air by estimating pulmonary dead space through reconstructing volumetric capnography (Vcap) from time-CO and time-volume curves, validated with vacuum ultraviolet time-of-flight mass spectrometry (VUV-TOF MS).

Methods: Existing monitoring parameters, including time-volume and time-CO curves, were used to determine Vcap.

Twisted Dipole Ion Guide (TDIG) for Flexible Ion Transfer in Atmospheric Pressure Ionization Mass Spectrometry.

In ambient mass spectrometry, the performance in direct in situ analysis applications has been hindered by the lack of efficient ion-transferring technique between the atmosphere pressure ionization source and the mass analyzer. Building upon the hybrid concept of a stack ring ion guide and multipole ion guide, this study proposes the concept of a reconfigurable twisted dipole ion guide (TDIG) that enables flexible ion transfer between atmosphere and vacuum. Initially, theoretical and numerical studies were conducted to understand the basic ion confining principle of the twisted dipole ion guide, revealing its unique merits in long-distance flexible ion transmission.

Correlations between propofol concentration in exhaled breath and BIS in patients undergoing thyroid surgery.

Several clinical studies have reported promising correlations between propofol concentration in exhaled breath (Ce-pro) and the bispectral index (BIS) in patients, suggesting the potential of exhaled propofol measurement as a non-invasive method for adjusting anesthesia depth. However, these studies are still in the validation phase of instrument effectiveness, often limited by small sample sizes or inappropriate instrument selection, and thus lack convincing results regarding these correlations. In this study, one hundred patients aged 18-65, undergoing elective thyroid surgery under general anesthesia were included.

A Novel Accurate Peak Extraction Algorithm of Mass Spectrometry Based on Iterative Adaptive Curve Fitting.

In the analysis of mass spectrometry, the peak identification from the overlapped region is necessary yet difficult. Although various methods have been developed to identify these peaks, especially the continuous wavelet transformation, their applications are still limited and it is hard to deal with the complex overlapped peaks. In this study, a novel peak extraction algorithm of mass spectrometry based on iterative adaptive curve fitting is proposed to address these challenges.

A study of the transient gas flow affected ion transmission in atmospheric pressure interfaces based on large eddy simulation for electrospray ionization mass spectrometry.

Modern atmosphere pressure interface (API) enables high-efficiency coupling between mass analyzers in high vacuum and atmosphere ionization sources such as electrospray ionization (ESI) source. The transient gas flow entering API possesses strong compressibility and turbulent characteristics, which exerts a huge impact on ion transmission. However, the instantaneous nature and vortical morphology of the turbulence in API and its affection in ion transmission were hardly covered in the reported research.

Exhaled breath is found to be better than blood samples for determining propofol concentrations in the brain tissues of rats.

The correlation between propofol concentration in exhaled breath () and plasma () has been well-established, but its applicability for estimating the concentration in brain tissues () remains unknown. Given the impracticality of directly sampling human brain tissues, rats are commonly used as a pharmacokinetic model due to their similar drug-metabolizing processes to humans. In this study, we measured,, andin mechanically ventilated rats injected with propofol.

CPEB2 inhibit cell proliferation through upregulating p21 mRNA stability in glioma.

Glioma is the most common primary malignant brain tumor in adults and remains an incurable disease at present. Thus, there is an urgent need for progress in finding novel molecular mechanisms that control the progression of glioma which could be used as therapeutic targets for glioma patients. The RNA binding protein cytoplasmic polyadenylate element-binding protein 2 (CPEB2) is involved in the pathogenesis of several tumors.

The High-Efficiency Calculation and Analysis of Different Quadrupole Fields Based on the Method of Fundamental Solution.

The calculation and analysis of electric fields are indispensable steps in the design of mass spectrometry. In this work, an approach for this calculation was established based on the method of fundamental solution (MFS). It was proved to be much faster and more accurate than the other popular methods, and its optimum parameters were found for the calculation of different quadrupole fields.

A new Mn-based layered cathode with enlarged interlayer spacing for potassium ion batteries.

Layered Mn-based cathode (KMnO) has attracted wide attention for potassium ion batteries (PIBs) because of its high specific capacity and energy density. However, the structure and capacity of KMnO cathode are constantly degraded during the cycling due to the strong Jahn-Teller effect of Mn and huge ionic radius of K. In this work, lithium ion and interlayer water were introduced into Mn layer and K layer in order to suppress the Jahn-Teller effect and expand interlayer spacing, respectively, thus obtaining new types of KMnLiO·0.

Sandwiched composite electrolyte with excellent interfacial contact for high-performance solid-state sodium-ion batteries.

Solid-state sodium-ion batteries have attracted significant attention due to their rich resources, high safety, and high energy density. However, the lower ionic conductivity and inferior interfacial contact between solid-state electrolytes (SSEs) and electrodes limit their practical applications. Herein, polyvinylideneuoride-co-hexauoropropylene (PVDF-HFP) membrane is selected and a novel sandwiched composite PVDF-HFP/NaZrCeSiPOF/PVDF-HFP (G-NZC0.

Calibration and validation of ultraviolet time-of-flight mass spectrometry for online measurement of exhaled ciprofol.

Ciprofol (HSK 3486, CHO), a novel 2,6-disubstituted phenol derivative similar to propofol, is a new type of intravenous general anaesthetic. We found that the exhaled ciprofol concentration could be measured online by ultraviolet time-of-flight mass spectrometry (UV-TOFMS), which could be used to predict the plasma concentration and anaesthetic effects of ciprofol. In this study, we present the calibration method and validation results of UV-TOFMS for the quantification of ciprofol gas.

A preclinical study on online monitoring of exhaled ciprofol concentration by the ultraviolet time-of-flight spectrometer and prediction of anesthesia depth in beagles.

Background: Exhaled air has been demonstrated as a reliable medium for monitoring propofol concentration. However, online monitoring of exhaled ciprofol have not been reported.

Methods: Thirty-six beagles undergoing mechanical ventilation were divided into 6 groups, including bolus injection of low (Group BL, n = 6), medium (Group BM, n = 6), and high dose of ciprofol (Group BH, n = 6) groups; as well as 1 h continuous infusion of low (Group IL, n = 6), medium (Group IM, n = 6), and high dose of ciprofol (Group IH, n = 6) groups.

Rapid and Online Detection of Foodborne Bacteria via a Novel Ultraviolet Photoionization Time-of-Flight Mass Spectrometry.

Foodborne bacteria are widespread contaminated sources of food; hence, the real-time monitoring of pathogenic bacteria in food production is important for the food industry. In this study, a novel rapid detection method based on microbial volatile organic compounds (MVOCs) emitted from foodborne bacteria was established by using ultraviolet photoionization time-of-flight mass spectrometry (UVP-TOF-MS). The results showed obvious differences of MVOCs among the five species of bacteria, and the characteristic MVOCs for each bacterium were selected by a feature selection algorithm.

Assessment of an exhaled breath test using ultraviolet photoionization time-of-flight mass spectrometry for the monitoring of kidney transplant recipients.

Continuous monitoring for immunosuppressive status, infection and complications are a must for kidney transplantation (KTx) recipients. Traditional monitoring including blood sampling and kidney biopsy, which caused tremendous medical cost and trauma. Therefore, a cheaper and less invasive approach was urgently needed.

From droplets to ions: a comprehensive and consecutive ion formation modelling in atmosphere pressure interface of electrospray ionization mass spectrometry.

In this study, we propose a novel ion formation simulation method for electrospray ionization (ESI) and atmosphere pressure interface (API). In this method, not the sheer particle trajectory, but the evolution of droplets and the offspring of gaseous ions are introduced instead. For the first time, the dynamic droplet-to-ion transformation process in the API of ESI-MS is visualized.

Development of mass spectrometry imaging techniques and its latest applications.

Mass spectrometry imaging (MSI) is a novel molecular imaging technology that collects molecular information from the surface of samples in situ. The spatial distribution and relative content of various compounds can be visualized simultaneously with high spatial resolution. The prominent advantages of MSI promote the active development of ionization technology and its broader applications in diverse fields.

Volatolomics analysis of exhaled breath and gastric-endoluminal gas for distinguishing early upper gastrointestinal cancer from benign.

Exhaled breath and gastric-endoluminal gas (volatile products of diseased tissues) contain a large number of volatile organic compounds, which are valuable for early diagnosis of upper gastrointestinal (UGI) cancer. In this study, exhaled breath and gastric-endoluminal gas of patients with UGI cancer and benign disease were analyzed by gas chromatography-mass spectrometry (GC-MS) and ultraviolet photoionization time-of-flight mass spectrometry (UVP-TOFMS) to construct UGI cancer diagnostic models. Breath samples of 116 UGI cancer and 77 benign disease subjects and gastric-endoluminal gas samples of 114 UGI cancer and 76 benign disease subjects were collected.

Reaching the initial coulombic efficiency and structural stability limit of P2/O3 biphasic layered cathode for sodium-ion batteries.

The P2/O3 biphasic layered oxide (NaMnMO, M: doping elements) is a cathode family with great promise for sodium-ion batteries (SIBs) because of their tunable electrochemical performance and low cost. However, the ultrahigh initial coulombic efficiency (ICE) and inferior cycling performance of P2/O3-NaMnMO need to be improved for practical application. Herein, Ni/Cu co-doped P2/O3-NaMnNiCuO materials are well-designed.

Identification of a small-molecule RPL11 mimetic that inhibits tumor growth by targeting MDM2-p53 pathway.

Background: Targeting ribosome biogenesis to activate p53 has recently emerged as a therapeutic strategy in human cancer. Among various ribosomal proteins, RPL11 centralizes the nucleolar stress-sensing pathway by binding MDM2, leading to MDM2 inactivation and p53 activation. Therefore, the identification of MDM2-binding RPL11-mimetics would be valuable for anti-cancer therapeutics.

Elucidation of formation mechanism responsible for charge-transfer reagent ions in microwave induced plasma desorption ionization (MIPDI) source.

Charge transfer reagent ions NO and O were major observed in microwave-induced plasma desorption ionization (MIPDI) source. Ions NO was prosperous in the discharge region while ions O generated in the afterglow region. Fundamental aspects of conditions that controlled MIPDI were addressed here to help understand the specific role of atmospheric components for charge transfer reagent ions formation.

CPEB4 Inhibit Cell Proliferation via Upregulating p21 mRNA Stability in Renal Cell Carcinoma.

Cytoplasmic polyadenylation element-binding protein 4 (CPEB4) has been reported to be dysregulated in a variety of cancers and seems to play paradoxical roles in different cancers. However, the functional roles of CPEB4 in Renal cell carcinoma (RCC) are still unclear. This study aims to explore the role and underlying mechanism of CPEB4 in RCC.

A p53/CPEB2 negative feedback loop regulates renal cancer cell proliferation and migration.

The tumor suppressor p53 transactivates the expression of multiple genes to exert its multifaceted functions and ultimately maintains genome stability. Thus, cancer cells develop various mechanisms to diminish p53 expression and bypass the cell cycle checkpoint. In this study, we identified the gene encoding RNA-binding protein cytoplasmic polyadenylation element-binding protein 2 (CPEB2) as a p53 target.

Ultrasensitive and Simultaneous Detection of Multielements in Aqueous Samples Based on Biomimetic Array Combined with Laser-Induced Breakdown Spectroscopy.

Ultrasensitive detection of metallic elements in liquids has attracted considerable attention in fields such as environmental pollution monitoring and drinking water quality control. Hence, it is of great significance to develop a sensitive and simultaneous detection strategy for multiple metal elements in liquid. Laser-induced breakdown spectroscopy (LIBS) technology shows unique advantages because of its simple, rapid, and real-time in situ detection, but the laser energy will be greatly attenuated in the liquids; thus, the sensitivity of LIBS for direct detection of metal elements in liquid samples will decrease sharply.

Low-cost smartphone-based LIBS combined with deep learning image processing for accurate lithology recognition.

A low-cost and multi-channel smartphone-based spectrometer was developed for LIBS. As the CMOS detector is two-dimensional, simultaneous multichannel detection was achieved by coupling a linear array of fibres for light collection. Thus, besides the atomic information, the spectral images containing the propagation and spatial distribution characters of a laser induced plasma plume could be recorded.