Testing adulterated liquid-egg: developing rapid detection techniques based on colorimetry, electrochemistry, and interfacial fingerprinting

To develop rapid detection techniques for liquid eggs' adulteration, three types of adulterations were considered: water dilution, manipulation of yolk ratio in whole egg, and blending different varieties of egg white or yolk. Objective: Establish detection techniques utilizing colorimetry, electrochemistry, and interfacial fingerprinting for these adulterations, respectively. Results: Colorimetry allows for detection (1 min·sample-1) of water dilution through linear (R2 ≥ 0.984) and exponential fitting (R2 ≥ 0.992); Electrochemistry enables detection (6 min·sample-1, R2 ≥ 0.979) of the adulteration of yolk ratio in whole egg; Interfacial fingerprinting technique effectively detects (detection duration: 10 min·sample-1, detection limit: 1.0-10.0 wt%) the adulteration of different varieties of egg white. Subsequently, through 3D-fluorescence microscopy (interface height variation: 22.49-573.45 μm), interfacial tension variation (65.54-35.48 mN·m-1), contact angle variation (89.7°-32.9°), particle size range (free water: 0.94-14.29 μm; protein aggregation: 6.57-10.76 μm), and etc., interfacial fingerprinting mechanism was elucidated. This research contributes novel insights into the detection of adulteration in liquid eggs.

Potassium Chloride as an Effective Alternative to Sodium Chloride in Delaying the Thermal Aggregation of Liquid Whole Egg

The potential of potassium chloride (KCl) to be used as a substitute for sodium chloride (NaCl) was studied by monitoring the effects of salt treatment on thermal behavior, aggregation kinetics, rheological properties, and protein conformational changes. The results show that the addition of KCl can improve solubility, reduce turbidity and particle size, and positively influence rheological parameters such as apparent viscosity, consistency coefficient (K value), and fluidity index (n). These changes indicate delayed thermal denaturation. In addition, KCl decreased the content of β-sheet and random coil structures and increased the content of α-helix and β-turn structures. The optimal results were obtained with 2% KCl addition, leading to an increase in Tp up to 85.09 °C. The correlation results showed that Tp was positively correlated with solubility, α-helix and β-turn but negatively correlated with ΔH, turbidity, β-sheet and random coil. Overall, compared to NaCl, 2% KCl is more effective in delaying the thermal aggregation of LWE, and these findings lay a solid theoretical foundation for the study of sodium substitutes in heat-resistant liquid egg products.

Deteriorated bone microarchitecture caused by sympathetic overstimulation in pheochromocytoma and paraganglioma

PURPOSE

Despite the potentially destructive effect of sympathetic activity on bone metabolism, its impact on bone microarchitecture, a key determinant of bone quality, has not been thoroughly investigated. This study aims to evaluate the impact of sympathetic activity on bone microarchitecture and bone strength in patients with pheochromocytoma and paraganglioma (PPGL).

METHODS

A cross-sectional study was conducted in 38 PPGL patients (15 males and 23 females). Bone turnover markers serum procollagen type 1 N-terminal propeptide (P1NP) and β-carboxy-terminal crosslinked telopeptide of type 1 collagen (β-CTX) were measured. 24-h urinary adrenaline (24hUE) and 24-h urinary norepinephrine levels (24hUNE) were measured to indicate sympathetic activity. High-resolution peripheral quantitative computed tomography (HR-pQCT) was conducted to evaluate bone microarchitecture in PPGL patients and 76 age-, sex-matched healthy controls (30 males and 46 females). Areal bone mineral density (aBMD) was measured by dual-energy X-ray absorptiometry (DXA) simultaneously.

RESULTS

PPGL patients had a higher level of β-CTX. HR-pQCT assessment revealed that PPGL patients had notably thinner and more sparse trabecular bone (decreased trabecular number and thickness with increased trabecular separation), significantly decreased volume BMD (vBMD), and bone strength at both the radius and tibia compared with healthy controls. The deterioration of Tt.vBMD, Tb.Sp, and Tb.1/N.SD was more pronounced in postmenopausal patients compared with the premenopausal subjects. Moreover, subjects in the highest 24hUNE quartile (Q4) showed markedly lower Tb.N and higher Tb.Sp and Tb.1/N.SD at the tibia than those in the lowest quartile (Q1). Age-related bone loss was also exacerbated in PPGL patients to a certain extent.

CONCLUSIONS

PPGL patients had significantly deteriorated bone microarchitecture and strength, especially in the trabecular bone, with an increased bone resorption rate. Our findings provide clinical evidence that sympathetic overstimulation may serve as a secondary cause of osteoporosis, especially in subjects with increased sympathetic activity.

Population genetic variation and geographic distribution of suitable areas of Coptis species in China

Introduction

The rhizomes of Coptis plants have been used in traditional Chinese medicine over 2000 years. Due to increasing market demand, the overexploitation of wild populations, habitat degradation and indiscriminate artificial cultivation of Coptis species have severely damaged the native germplasms of species in China.

Methods

Genome-wide simple-sequence repeat (SSR) markers were developed using the genomic data of C. chinensis. Population genetic diversity and structure of 345 Coptis accessions collected from 32 different populations were performed based on these SSRs. The distribution of suitable areas for three taxa in China was predicted and the effects of environmental variables on genetic diversity in relation to different population distributions were further analyzed.

Results

22 primer pairs were selected as clear, stable, and polymorphic SSR markers. These had an average of 16.41 alleles and an average polymorphism information content (PIC) value of 0.664. In the neighbor-joining (N-J) clustering analysis, the 345 individuals clustered into three groups, with C. chinensis, C. chinensis var. brevisepala and C. teeta being clearly separated. All C. chinensis accessions were further divided into four subgroups in the population structure analysis. The predicted distributions of suitable areas and the environmental variables shaping these distributions varied considerably among the three species.

Discussion

Overall, the amount of solar radiation, precipitation and altitude were the most important environmental variables influencing the distribution and genetic variation of three species. The findings will provide key information to guide the conservation of genetic resources and construction of a core reserve for species.

Effects of freezing on the gelation behaviors of liquid egg yolks affected by saccharides: thermal behaviors and rheological and structural changes

Monitoring and controlling the freezing process and thermal properties of foods is an important means to understand and maintain product quality. Saccharides were used in this study to regulate the gelation of liquid egg yolks induced by freeze‒thawing; the selected saccharides included sucrose, L-arabinose, xylitol, trehalose, D-cellobiose, and xylooligosaccharides. The regulatory effects of saccharides on frozen egg yolks were investigated by characterizing their thermal and rheological properties and structural changes. The results showed that L-arabinose and xylitol were effective gelation regulators. After freeze‒thawing, the sugared egg yolks exhibited a lower consistency index and fewer rheological units than those without saccharides, indicating controlled gelation. Weaker aggregation of egg yolk proteins was confirmed by smaller aggregates observed by confocal laser scanning microscopy and smaller particle sizes. Saccharides alleviated the freeze-induced conversion of α-helices to β-sheets in egg yolk proteins, exposing fewer Trp residues. Overall, L-arabinose showed the greatest improvement in regulating the gelation of egg yolks, followed by xylitol, which is correlated with its low molecular weight.

Effect of Whole Egg Liquid on Physicochemical, Quality, Fermentation and Sensory Characteristics of Yogurt

With the purpose of developing an alternative set yogurt with high consumer acceptability, liquid whole egg (LWE), at levels that varied from 0 to 30%, was incorporated into set yogurt, and the effects on the physicochemical, quality, fermentation, and sensory characteristics of yogurt were evaluated. The fat content was lower in egg yogurt than in control yogurt. All color variables were significantly affected by LWE amount. The amount of bacteria in the egg yogurt was greater than in the control yogurt. Sensory analysis data suggested that color, odor, and texture consistently impacted the overall acceptability of the egg yogurt. The addition of 5% whole egg, which resulted in an increase of 6.28-fold in hardness, increase of 6.1-fold in viscosity, decrease in pH values, and a 5.6% decline in water-holding capacity (WHC). The aroma and flavor of the set yogurt was improved as well. LWE addition significantly increased the protein content and dynamic rheology. More importantly, the addition of LWE increased the protein content of the set yogurt. This investigation demonstrated the feasibility of fabricating LWE-enriched set yogurt and its superior quality compared with the corresponding normal product. It also emphasized the reconstruction of LWE with enhanced properties.

High-temperature glycosylation of saccharides to modify molecular conformation of egg white protein and its effect on the stability of high internal phase emulsions

This paper investigates the freeze-thaw stability of oil-in-water emulsions stabilized by high-temperature wet heating glycosylation products. Glucose (Glu), D-fructose (Fru), xylose (Xyl), maltodextrin (MD), oligofructose (FO), and oligomeric isomaltulose (IMO) were chosen as sugar sources for the glycosylation reaction with egg white proteins (EWPs) at 120 °C to prepare the GEWPs. The study reveals that the type of sugar significantly influences the Maillard reactions with EWPs. The degree of glycosylation was highest in the Xyl group with the greatest reducing capacity and lowest in the MD, FO, and IMO groups. High-temperature wet glycosylation treatment induced changes in the secondary and tertiary structures of EWP. Elevated temperature exposed hydrophobic groups within the protein, while covalent binding of hydrophilic carbohydrates via the Maillard reaction decreased the protein's H0 value. Improved foaming and emulsifying properties were attributed to the increase in α-helix content, disulfide bond formation, and reduced surface tension. Emulsions prepared from GEWPs exhibited higher apparent viscosity and G' compared to those from natural EWPs, with the GEWP/Xyl group showing the highest values. After freeze-thaw treatment, the GEWP/Fru and GEWP/FO groups demonstrated superior stability and reduced freezing point, along with minimal microstructural alterations. These findings underscore the importance of sugar type in the stability of high internal phase emulsions (HIPEs) stabilized by GEWPs, indicating that a tailored Maillard reaction can yield stabilizers with exceptional freeze-thaw stability for emulsions.

Tracking transformation behavior of soluble to insoluble components in liquid egg yolk under heat treatment and the intervention effect of xylitol

The heat sensitivity of egg yolk limits its application, and xylitol can improve its thermal stability. The soluble and insoluble components of egg yolk and egg yolk containing xylitol treated at different temperatures were explored from the aspects of thermal instability behavior characterization and structure property. Magnetic resonance imaging and low field nuclear magnetic resonance showed that increased temperature induced liberation and transfer of hydrogen protons. Meanwhile, the apparent viscosity of soluble components increased, while that of insoluble components decreased. Microstructure showed that heat treatment induced aggregation and lipid transfer. SDS-PAGE showed that heat treatment induced aggregation and transformation of γ-livetin and apo-LDL. The change in crystal structure, Raman spectroscopy, and 3D fluorescence spectra showed that heat treatment resulted in the unfolding of yolk proteins, especially plasma proteins. Xylitol could alleviate transformation of components by stabilizing protein structure, alleviating the damage in protein integrity and elevation in aggregation size.

Interventional effect of compound sugar and salt on the thermal instability behavior of liquid egg yolk

In this study, the influence of compound sugar (glucose, sucrose, trehalose, and arabinose) and compound sugar and salt (glucose, sucrose, trehalose, arabinose, and NaCl) on the thermal stability of heat-treated liquid egg yolk was explored. The results showed that the addition of 4% compound sugar or 4% compound sugar salt could significantly enhance the heat resistance of liquid egg yolk and increase the denaturation temperature of liquid egg yolk to above 77°C. Moreover, the addition of sugar and salt could improve the functional properties of liquid egg yolk to varying degrees, allowing it to maintain excellent emulsification and soluble protein content after heat treatment. Further analysis using Fourier transform infrared spectroscopy showed that the increase in α-helix content in liquid egg yolk treated with sugar salt also contributes to improving the thermal stability of egg yolk. The method of inhibiting egg yolk aggregation caused by heat treatment provided in this study provides a selective method and theoretical basis for the commercial production of heat-resistant liquid egg yolk.

Effects of CaCl2 on the structure of high-density lipoprotein and low-density lipoprotein isolated from rapidly salted separated egg yolk

According to previous research, adding CaCl2 to the salting solution improves the quality of salted separated egg yolk. To further understand the improvement mechanism of CaCl2, this paper investigated the effect of CaCl2 on the structure of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) during the salting process. The results indicated that the addition of CaCl2 can affect the composition of HDL and LDL apolipoproteins, improving the orderliness of the HDL structure and the looseness of the LDL structure. It was discovered by atomic force microscopy (AFM) that adding CaCl2 to the salting solution can weaken the aggregation behavior of HDL. Simultaneously, the addition of CaCl2 decreased the relative content of intermolecular β-sheets in the secondary structure of HDL and LDL, influenced their tertiary conformation, and prevented HDL and LDL from participating in the formation of a three-dimensional gel structure by influencing their hydrogen bonds and hydrophobic interactions.

Effects of CaCl2 on the rheology, microstructure and protein structures of rapidly salted separated egg yolk

Bivalent or trivalent metal salts can enhance the oil output and sandiness of salted eggs. We added CaCl2 to the salting solution to improve the quality of rapidly salted separated egg yolk and investigated its effect on rheological, microstructure, and protein structure. According to the findings, adding CaCl2 to the salting solution can promote the precipitation of egg yolk water, increase its viscosity, induce protein aggregation, and increase the denaturation temperature of the protein. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) revealed that the inner boundary of egg yolk salted with CaCl2 was clearer and that the number and size of salted egg yolk lipoprotein aggregates were larger than those of egg yolk salted without CaCl2. Analysis using Fourier transform infrared spectroscopy (FTIR) demonstrated that CaCl2 caused the interconversion of the secondary-level structure. CaCl2 can have an impact on the microenvironment of amino acid residues, according to the results of 3D fluorescence and UV absorption spectra. Therefore, adding CaCl2 can accelerate the loss of water and change the structure of lipoprotein in egg yolk, which improves the sandiness and oil yield of salted separated egg yolk.

[Establishment of a digital remote platform for respiratory support and intelligent early warning in intensive care units]

During the disease progression or treatment of critically ill patients with lung injury, the changes in respiratory mechanics are continuous and dynamic. Establishing a digital platform for respiratory support in the ICU, which enables the continuous recording, dynamic analysis, and real-time alerting of numerical and waveform data from mechanical ventilation, can help intensivists improve their understanding of "dynamic respiratory mechanics", improve respiratory therapy and patient outcomes, as well as reduce workload and increase work efficiency. The construction of a dedicated database for mechanical ventilation, based on ventilator waveforms provides essential data support for projects such as respiratory mechanics data algorithm models. This will facilitate the establishment of an auxiliary decision-making system, enable the realization of intelligent mechanical ventilation, and create a new era of dynamic respiratory mechanics.

Changes in structural, rheological, and gel properties of egg white protein induced by preheating in the dry state

The knowledge of fundamental rheological concepts is essential to understand the gelling process of egg white proteins (EWP), which can be used to further manipulate the gel performance with desired sensorial attributes. In this study, the rheological and gel properties of EWP as influenced by heating in the dry state were investigated. The structural changes in dry heated EWP (DEWP) were also characterized in terms of morphology, protein stability, and protein microenvironment. The results showed that moderate dry heating induced linear aggregation of DEWP and decreased the denaturation temperature (Td) and enthalpy of denaturation (ΔH). Furthermore, the cross-linking on protein surface led to nonpolar microenvironment of hydrophobic groups, which lays the foundation of improved gel properties. The specific outcomes include the increase in the G'max and the G''max values, k'/k'' values of DEWP dispersions, gel hardness and gumminess of DEWP gels and a decrease in gelation temperature of DEWP dispersions. However, few changes were found in the springiness and cohesiveness of the DEWP gels with increasing dry heating time. Notably, gels prepared with DEWP also had better digestibility. Overall, these results can provide theoretical basis for quality control and sensory evaluation of DEWP in the food industry.

[A case report of autosomal recessive bestrophinopathy]

The patient is a 40-year-old male who presented to the ophthalmology clinic due to easy visual fatigue for the past 3 months. Two months ago, the patient was misdiagnosed with "bilateral posterior uveitis", but the diagnosis was ruled out after ineffective treatment with corticosteroids. During the current visit, fundus examination revealed yellow-white material exudation below the macular center in both eyes. Considering the results of the ophthalmic examination and the genetic testing of the patient and his son, the patient was diagnosed with autosomal recessive bestrophinopathy.

[The 501st case: elevated blood glucose, chronic pancreatitis, and post- pancreatoduodenectomy malnutrition]

A 50-year-old man with a 15-year history of elevated blood glucose and an approximately 2-year history of diarrhea was admitted to the Peking Union Medical College Hospital. The initial diagnosis was type 2 diabetes. After repeated pancreatitis and pancreatoduodenectomy, severe pancreatic endocrine and exocrine dysfunction including alternating high and low blood glucose and fat diarrhea occurred. Tests for type 1 diabetes-related antibodies were all negative, C-peptide levels were substantially reduced, fat-soluble vitamin levels were reduced, and there was no obvious insulin resistance. Therefore, a diagnosis of pancreatic diabetes was clear. The patient was given small doses of insulin and supplementary pancreatin and micronutrients. Diarrhea was relieved and blood glucose was controlled. The purpose of this article is to raise clinicians' awareness of the possibility of pancreatic diabetes after pancreatitis or pancreatic surgery. Timely intervention and monitoring may reduce the occurrence of complications.

High-temperature glycosylation modifies the molecular structure of ovalbumin to improve the freeze-thaw stability of its high internal phase emulsion

In this study, ovalbumins (OVAs) were glycosylated with fructo-oligosaccharide (FO) at different temperatures (80 °C, 100 °C, 120 °C, and 140 °C) and durations (1 h and 2 h) via wet-heating. The glycosylated OVAs (GOVAs) were characterized by the degree of glycosylation (DG), particle size, zeta potentials, and structural changes. GOVAs-stabilized high-internal-phase emulsions (HIPEs) were then prepared to compare their macro- and microstructure and freeze-thaw stability. The results showed that the DG of GOVAs increased with the increase in glycosylation temperature and the protein structure unfolded with it. Glycosylation decreased the particle size, zeta potential, and α-helical structures and increased the β-sheets and surface hydrophobicity (H₀) of GOVAs compared with unmodified OVAs. Moreover, GOVAs-stabilized HIPEs exhibited smaller particle sizes, zeta potentials, agglomeration indexes, oil loss rates, and freezing points and higher viscoelasticity, centrifugal stabilities, flocculation indexes, and freeze-thaw stabilities. Notably, HIPEs prepared by GOVAs (glycosylated higher than 120 °C) showed the least changes in macro- and microscopic appearances after freeze-thawing. These findings will provide a novel method for improving and broadening the functionalities of OVAs and potentially develop HIPEs with enhanced freeze-thaw stabilities.

Effects of Heating Treatment on Functional and Structural Properties of Liquid Whole Egg

Liquid whole egg (LWE) products have many advantages such as convenient transportation, easy production and are safe. However, LWE has a short shelf life and high thermal sensitivity, so suitable heating treatment is the key to the production of LWE products. The aim of this study is to investigate the effects of heating treatments conditions (at 55–67 °C for 0–10 min) on the emulsification, foaming activity and rheological properties of LWE. The results indicated that the emulsifying activity of LWE had no significant change after 55–64 °C heating treatment, while it decreased significantly after heating treatment at 67 °C. The foaming property of LWE increased significantly after 55 °C to the 64 °C heating treatment; while the foaming property showed a downward trend with the increase in heat treatment temperature, it can significantly improve the foam stability of LWE. The heating treatment thoroughly changed the molecular weight distribution of LWE protein, thus promoted the protein surface hydrophobicity, hydrophobicity activity and rheological properties. The heating treatment at 61 °C for 6 min had a better effect on the functional properties than that of the other heating groups. In addition, the results of this study provide the change in rules of LWE under different heating treatment conditions and provide theoretical guidance for the production and processing of LWE.

High prevalence of vertebral deformity in tumor-induced osteomalacia associated with impaired bone microstructure

PURPOSE

Patients with tumor-induced osteomalacia (TIO) often suffer from irreversible height loss due to vertebral deformity. However, the prevalence of vertebral deformity in TIO patients varies among limited studies. In addition, the distribution and type of vertebral deformity, as well as its risk factors, remain unknown. This study aimed to identify the prevalence, distribution, type and risk factors for vertebral deformity in a large cohort of TIO patients.

METHODS

A total of 164 TIO patients were enrolled in this retrospective study. Deformity in vertebrae T4-L4 by lateral thoracolumbar spine radiographs was evaluated according to the semiquantitative method of Genant. Bone microstructure was evaluated by trabecular bone score (TBS) and high-resolution peripheral QCT (HR-pQCT).

RESULTS

Ninety-nine (99/164, 60.4%) patients had 517 deformed vertebrae with a bimodal pattern of distribution (T7-9 and T11-L1), and biconcave deformity was the most common type (267/517, 51.6%). Compared with patients without vertebral deformity, those with vertebral deformity had a higher male/female ratio, longer disease duration, more height loss, lower serum phosphate, higher bone turnover markers, lower TBS, lower areal bone mineral density (aBMD), lower peripheral volumetric BMD (vBMD) and worse microstructure. Lower trabecular vBMD and worse trabecular microstructure in the peripheral bone and lower spine TBS were associated with an increased risk of vertebral deformity independently of aBMD. After adjusting for the number of deformed vertebrae, we found little difference in clinical indexes among the patients with different types of vertebral deformity. However, we found significant correlations of clinical indexes with the number of deformed vertebrae and the spinal deformity index.

CONCLUSION

We reported a high prevalence of vertebral deformity in the largest cohort of TIO patients and described the vertebral deformity in detail for the first time. Risk factors for vertebral deformity included male sex, long disease duration, height loss, abnormal biochemical indexes and bone impairment. Clinical manifestation, biochemical indexes and bone impairment were correlated with the number of deformed vertebrae and degree of deformity, but not the type of deformity.

Metabolic regulation mechanism of Trametes gibbosa CB_1 on lignin

White rot fungi can degrade lignin and play a significant role in the recycling of carbon resources for environmental protection. Trametes gibbosa is the main white rot fungus in Northeast China. The main acids produced by T. gibbosa degradation, include long-chain fatty acids, lactic acid, succinic acid, and some small molecular compounds for example benzaldehyde. A variety of proteins respond to lignin stress and play an important role in xenobiotics metabolism, metal ion transport, and redox. Coordinated regulation and detoxification activation of H₂O₂ produced in oxidative stress by peroxidase coenzyme system and Fenton reaction. The Dioxygenase cleavage pathway and β-ketoadipic acid pathway are the main oxidation pathways of lignin degradation, which mediate the entry of "COA" into the TCA cycle. In the joint action of hydrolase and coenzyme, cellulose, hemicellulose, and other polysaccharides are degraded and finally converted to glucose to participate in energy metabolism. The expression of the laccase (Lcc_1) protein was verified by E. coli. Also, the Lcc_1 overexpression mutant was established. The morphology of mycelium was dense and the lignin degradation rate was improved. We completed the first non-directional mutation of in T. gibbosa. It also improved the mechanism of T. gibbosa in response to lignin stress.

Addition of NaCl or Sucrose on the Protein Content, and Functional and Physicochemical Properties of Egg Whites Liquid under Heat Treatment

In this study, differences in the protein content and functional and physicochemical properties of four varieties of egg white (EW) were studied by adding 4-10% sucrose or NaCl and then heating them at 70 °C for 3 min. According to a high-performance liquid chromatography (HPLC) analysis, the percentages of ovalbumin, lysozyme and ovotransferrin rose with an increase in the NaCl or sucrose concentration; however, the percentages of ovomucin and ovomucoid decreased. Furthermore, the foaming properties, gel properties, particle size, α-helixes, β-sheets, sulfhydryl groups and disulfide bond content also increased, whereas the content of β-turns and random coils decreased. In addition, the total soluble protein content and functional and physicochemical properties of black bone (BB) chicken and Gu-shi (GS) EWs were higher than those of Hy-Line brown (HY-LINE) and Harbin White (HW) Ews (p < 0.05). Subsequently, transmission electron microscopy (TEM) confirmed the changes in the EW protein structure in the four varieties of Ews. As the aggregations increased, the functional and physicochemical properties decreased. The protein content and functional and physicochemical properties of Ews after heating were correlated with the concentration of NaCl and sucrose and the EW varieties.

Transcriptomics and co-expression network analysis revealing candidate genes for the laccase activity of Trametes gibbosa

BACKGROUND

Trametes gibbosa, which is a white-rot fungus of the Polyporaceae family found in the cold temperate zone, causes spongy white rot on wood. Laccase can oxidize benzene homologs and is one of the important oxidases for white rot fungi to degrade wood. However, the pathway of laccase synthesis in white rot fungi is unknown.

RESULTS

The peak value of laccase activity reached 135.75 U/min/L on the 9th day. For laccase activity and RNA-seq data, gene expression was segmented into 24 modules. Turquoise and blue modules had greater associations with laccase activity (positively 0.94 and negatively -0.86, respectively). For biology function, these genes were concentrated on the cell cycle, citrate cycle, nicotinate, and nicotinamide metabolism, succinate dehydrogenase activity, flavin adenine dinucleotide binding, and oxidoreductase activity which are highly related to the laccase synthetic pathway. Among them, gene_8826 (MW199767), gene_7458 (MW199766), gene_61 (MW199765), gene_1741 (MH257605), and gene_11087 (MK805159) were identified as central genes.

CONCLUSION

Laccase activity steadily increased in wood degradation. Laccase oxidation consumes oxygen to produce hydrogen ions and water during the degradation of wood. Some of the hydrogen ions produced can be combined by Flavin adenine dinucleotide (FAD) to form reduced Flavin dinucleotide (FADH2), which can be transmitted. Also, the fungus was starved of oxygen throughout fermentation, and the NADH and FADH2 are unable to transfer hydrogen under hypoxia, resulting in the inability of NAD and FAD to regenerate and inhibit the tricarboxylic acid cycle of cells. These key hub genes related to laccase activity play important roles in the molecular mechanisms of laccase synthesis for exploring industrial excellent strains.

Effects of CaCl2 on salting kinetics, water migration, aggregation behavior and protein structure in rapidly salted separated egg yolks

Salted egg yolks are valued by consumers for their delicious taste good processing characteristics. To improve the quality of rapidly salted separated egg yolks, we compared changes in the salting kinetics, textural properties, water migration, protein aggregation and structure of salted egg yolks in the presence or absence of CaCl₂ for 24 h. CaCl₂ increased the mass transfer driving force and diffusion coefficient during the salting process; as a result, the salted egg yolks exhibited increased hardness and decreased springiness and cohesiveness. Through low field nuclear magnetic resonance (LF NMR), it was confirmed that CaCl₂ promoted the precipitation of lipids and the dehydration of egg yolk. Furthermore, CaCl₂ promoted the bulk aggregation of proteins. The analyses of protein structures showed that the contents of β-sheets and irregular curls in CaCl₂-salted egg yolk protein increased, while the contents of α-helices and β-turns decreased. CaCl₂ affected the microenvironment of tryptophan residues and embedded these residues, enhancing protein aggregation. Based on the comprehensive information obtained in this study, adding CaCl₂ to the salting solution improved the degree of protein polymerization in egg yolk; thus, this method might be used to improve the quality of egg yolks separated by salt.

Eggshell waste separation process assisted with pressure-vacuum: Process conditions and optimization

Eggshells and eggshell membranes have high-value recycling applications and have been widely used in pharmaceutical, chemical, and food research. The separation of eggshells and eggshell membranes is a prerequisite to efficiently using both. Therefore, the pressure-vacuum experiment equipment was designed. In this study, research on the separation of eggshells and eggshell membranes from waste eggshells using the pressure-vacuum experiment equipment was carried out. The flash evaporation experiment process controlled the experimental factors to obtain a sufficient moisture content between the eggshell and eggshell membrane with vigorous flash evaporation. The effects of experimental factors such as superheat (5-10°C), temperature (50-70°C), initial pressure (0.6-0.8 MPa), pressurization time (0-40 min), and particle size (6-8 mm) on the separation rate were investigated in the pressure-vacuum experiment process. Through single-factor and orthogonal experiments, it was found that the separation rate was most affected by changes in temperature, initial pressure, and particle size, followed by the interaction of temperature and particle size. The experimental results suggested that the optimum separation of eggshell membranes from eggshells was achieved at higher superheat, higher temperature, higher initial pressure, medium pressurization time, and smaller particle size. Through optimization by response surface methodology, the optimal conditions for the separation of eggshells and eggshell membranes using the flash evaporation method were determined as 15°C of superheat, 70°C of temperature, 0.8 MPa of initial pressure, and 6 mm of particle size. Flash evaporation method is an effective and environmentally friendly method, which provides a new solution for the recycling of waste eggshells. PRACTICAL APPLICATION: In this study, pressure-vacuum experiment equipment was utilized to reuse of waste eggshells, and an innovative and environmentally friendly method of eggshell membrane and eggshell separation was established. The pressure-vacuum experiment equipment has a simple structure and low energy consumption. The results of flash evaporation experiments are instructive for further in-depth studies on the separation of eggshells and eggshell membranes. Furthermore, the separation of eggshells and egg membranes by flash evaporation is of great research value. Most importantly, the separated eggshells and eggshell membrane are available for high-value applications in food, chemical, and biological fields.

Development and implementation of a metaphase DNA model for ionizing radiation induced DNA damage calculation

Objective. To develop a metaphase chromosome model representing the complete genome of a human lymphocyte cell to support microscopic Monte Carlo (MMC) simulation-based radiation-induced DNA damage studies.Approach. We first employed coarse-grained polymer physics simulation to obtain a rod-shaped chromatid segment of 730 nm in diameter and 460 nm in height to match Hi-C data. We then voxelized the segment with a voxel size of 11 nm per side and connected the chromatid with 30 types of pre-constructed nucleosomes and 6 types of linker DNAs in base pair (bp) resolutions. Afterward, we piled different numbers of voxelized chromatid segments to create 23 pairs of chromosomes of 1-5μm long. Finally, we arranged the chromosomes at the cell metaphase plate of 5.5μm in radius to create the complete set of metaphase chromosomes. We implemented the model in gMicroMC simulation by denoting the DNA structure in a four-level hierarchical tree: nucleotide pairs, nucleosomes and linker DNAs, chromatid segments, and chromosomes. We applied the model to compute DNA damage under different radiation conditions and compared the results to those obtained with G0/G1 model and experimental measurements. We also performed uncertainty analysis for relevant simulation parameters.Main results. The chromatid segment was successfully voxelized and connected in bps resolution, containing 26.8 mega bps (Mbps) of DNA. With 466 segments, we obtained the metaphase chromosome containing 12.5 Gbps of DNA. Applying it to compute the radiation-induced DNA damage, the obtained results were self-consistent and agreed with experimental measurements. Through the parameter uncertainty study, we found that the DNA damage ratio between metaphase and G0/G1 phase models was not sensitive to the chemical simulation time. The damage was also not sensitive to the specific parameter settings in the polymer physics simulation, as long as the produced metaphase model followed a similar contact map distribution.Significance. Experimental data reveal that ionizing radiation induced DNA damage is cell cycle dependent. Yet, DNA chromosome models, except for the G0/G1 phase, are not available in the state-of-the-art MMC simulation. For the first time, we successfully built a metaphase chromosome model and implemented it into MMC simulation for radiation-induced DNA damage computation.

Near-infrared photoglottography for measuring multiple glottal events

Near-infrared (NIR) photoglottography (PGG) is a non-invasive method for monitoring glottal activities which retains functionality of conventional PGG using visible light with more convenient accessibility. This paper is to investigate its performance in comparison with simultaneously recorded electroglottography (EGG) signals. Results showed that NIR PGG detects continuous transillumination for glottal aperture and vocal-fold contact. Glottal timing markers known as glottal closure and opening instants are detectable agreeing to the corresponding EGG-based instants. Further, it was inferred that variations of glottal waveforms based on NIR PGG reflect vertical vocal-fold edge motions.

Mechanistic modelling of oxygen enhancement ratio of radiation via Monte Carlo simulation-based DNA damage calculation

Objective.Oxygen plays an important role in affecting the cellular radio-sensitivity to ionizing radiation. The objective of this study is to build a mechanistic model to compute oxygen enhancement ratio (OER) using a GPU-based Monte Carlo (MC) simulation package gMicroMC for microscopic radiation transport simulation and DNA damage calculation.Approach.We first simulated the water radiolysis process in the presence of DNA and oxygen for 1 ns and recorded the produced DNA damages. In this process, chemical reactions among oxygen, water radiolysis free radicals and DNA molecules were considered. We then applied a probabilistic approach to model the reactions between oxygen and indirect DNA damages for a maximal reaction time oft0. Finally, we defined two parametersP0andP1, representing probabilities for DNA damages without and with oxygen fixation effect not being restored in the repair process, to compute the final DNA double strand breaks (DSBs). As cell survival fraction is mainly determined by the number of DSBs, we assumed that the same numbers of DSBs resulted in the same cell survival rates, which enabled us to compute the OER as the ratio of doses producing the same number of DSBs without and with oxygen. We determined the three parameters (t0,P0andP1) by fitting the OERs obtained in our computation to a set of published experimental data under x-ray irradiation. We then validated the model by performing OER studies under proton irradiation and studied model sensitivity to parameter values.Main results.We obtained the model parameters ast0= 3.8 ms,P0= 0.08, andP1= 0.28 with a mean difference of 3.8% between the OERs computed by our model and that obtained from experimental measurements under x-ray irradiation. Applying the established model to proton irradiation, we obtained OERs as functions of oxygen concentration, LET, and dose values, which generally agreed with published experimental data. The parameter sensitivity analysis revealed that the absolute magnitude of the OER curve relied on the values ofP0andP1, while the curve was subject to a horizontal shift when adjustingt0.Significance.This study developed a mechanistic model that fully relies on microscopic MC simulations to compute OER.

The development of a deep reinforcement learning network for dose-volume-constrained treatment planning in prostate cancer intensity modulated radiotherapy

Although commercial treatment planning systems (TPSs) can automatically solve the optimization problem for treatment planning, human planners need to define and adjust the planning objectives/constraints to obtain clinically acceptable plans. Such a process is labor-intensive and time-consuming. In this work, we show an end-to-end study to train a deep reinforcement learning (DRL) based virtual treatment planner (VTP) that can behave like a human to operate a dose-volume constrained treatment plan optimization engine following the parameters used in Eclipse TPS for high-quality treatment planning. We considered the prostate cancer IMRT treatment plan as the testbed. The VTP took the dose-volume histogram (DVH) of a plan as input and predicted the optimal strategy for constraint adjustment to improve the plan quality. The training of VTP followed the state-of-the-art Q-learning framework. Experience replay was implemented with epsilon-greedy search to explore the impacts of taking different actions on a large number of automatically generated plans, from which an optimal policy can be learned. Since a major computational cost in training was to solve the plan optimization problem repeatedly, we implemented a graphical processing unit (GPU)-based technique to improve the efficiency by 2-fold. Upon the completion of training, the established VTP was deployed to plan for an independent set of 50 testing patient cases. Connecting the established VTP with the Eclipse workstation via the application programming interface, we tested the performance the VTP in operating Eclipse TPS for automatic treatment planning with another two independent patient cases. Like a human planner, VTP kept adjusting the planning objectives/constraints to improve plan quality until the plan was acceptable or the maximum number of adjustment steps was reached under both scenarios. The generated plans were evaluated using the ProKnow scoring system. The mean plan score (± standard deviation) of the 50 testing cases were improved from 6.18 ± 1.75 to 8.14 ± 1.27 by the VTP, with 9 being the maximal score. As for the two cases under Eclipse dose optimization, the plan scores were improved from 8 to 8.4 and 8.7 respectively by the VTP. These results indicated that the proposed DRL-based VTP was able to operate the in-house dose-volume constrained TPS and Eclipse TPS to automatically generate high-quality treatment plans for prostate cancer IMRT.

The efficacy and safety of different doses of calcitriol combined with neutral phosphate in X-linked hypophosphatemia: a prospective study

The present study was the first prospective cohort evaluated the efficacy and safety of different doses of calcitriol in XLH children. The results suggested that a dose of 40 ng/kg/day calcitriol, compared with 20 ng/kg/day, was more effective in relieving the rickets, with similar safety outcomes. Further investigations were expected to set more dose groups.

INTRODUCTION

Dose recommended for calcitriol in X-linked hypophosphatemia (XLH) varies in different studies. Therefore, we aimed to compare the efficacy as well as the safety of 20 ng/kg/d and 40 ng/kg/d calcitriol in Chinese XLH pediatrics population.

METHODS

A 2-year, randomized, open-label, prospective study recruited 68 XLH children, which were randomized to receive either 40 ng/kg/day or 20 ng/kg/day calcitriol. Efficacy endpoints were the total Thacher ricket severity score (RSS) change from baseline to month 12 and 24, the difference in serum TALP level, fasting serum phosphate level, body height Z-score, and frequency of dental abscess. Safety assessments were done using renal ultrasound nephrocalcinosis grades (0-4), fasting serum and 24 h urine calcium level, and the occurrence of hyperparathyroidism.

RESULTS

The decrease in the total RSS from baseline was more significant in the high-dose group at 12 (difference 0.87, p = 0.049) and 24 month (difference 1.23, p = 0.011). The serum TALP level was significantly lower in the high-dose group at 6 months. Pi level, height Z-score change, frequency of dental abscess and ratio of de novo nephrocalcinosis were comparable. A lower incidence of secondary hyperparathyroidism was seen in the high-dose group (p < 0.0001).

CONCLUSION

For the first time in this prospective cohort, 40 ng/kg/d calcitriol was shown to be the more effective therapy in XLH children than the 20 ng/kg/d. Moreover, 40 ng/kg/d calcitriol was not associated with increasing adverse events.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT 03,820,518.

Treatment-related adverse events as predictive biomarkers of efficacy in patients with advanced neuroendocrine tumors treated with surufatinib: results from two phase III studies

Background

No validated biomarkers currently exist for predicting the efficacy outcomes in patients with neuroendocrine tumors (NETs) treated with antiangiogenic therapy. We aimed to evaluate the association between treatment-related adverse events (TRAEs) and efficacy outcomes of surufatinib in patients with advanced NET.

Patients and methods

We included patients with NET treated with surufatinib in two multicenter, randomized, double-blind, placebo-controlled, phase III trials (SANET-p and SANET-ep) in this study. The main exposure was the presence of any of the TRAEs including hypertension, proteinuria, and hemorrhage in the first 4 weeks of surufatinib treatment. The primary outcome of the study was investigator-assessed progression-free survival (PFS). PFS outcomes were estimated using the Kaplan–Meier method with the log-rank test. Hazard ratios (HRs) were calculated by using univariable and multivariable Cox proportional hazard regression models. Blinded independent image review committee (BIIRC) assessments and 4-week landmark analysis were also performed as supportive evaluations.

Results

During the study period, a total of 242 patients treated with surufatinib were included in the analysis, and 164 (68%) patients had at least one of hypertension, proteinuria, and hemorrhage in the first 4 weeks of treatment. The presence of TRAEs in the first 4 weeks was associated with prolonged median PFS [11.1 versus 9.2 months; HR 0.67, 95% confidence interval (CI) 0.47-0.97; P = 0.036]. In multivariable Cox regression analysis, the presence of TRAEs was also significantly associated with longer PFS (HR 0.65, 95% CI 0.44-0.97; P = 0.035). Similar results were obtained in the BIIRC assessments and 4-week landmark analysis.

Conclusions

Treatment-related hypertension, proteinuria, and hemorrhage could be potential biomarkers to predict antitumor efficacy of surufatinib in patients with advanced NET. Future prospective studies are needed to validate the findings.

Trial registration

ClinicalTrials.govNCT02589821; https://clinicaltrials.gov/ct2/show/NCT02589821 and ClinicalTrials.gov NCT02588170; https://clinicaltrials.gov/ct2/show/NCT02588170

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Treatment-related hypertension, proteinuria, or hemorrhage is associated with longer survival in NETs.

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The association is confirmed by the BIIRC assessments and 4-week landmark analysis.

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TRAEs can be biomarkers to predict antitumor efficacy in patients with NET.

[Treatment of 11 cases of juvenile idiopathic arthritis by intra-articular injection of adalimumab]

Objective: To evaluate the efficacy and safety of intra-articular injection of adalimumab (ADA) in the treatment of refractory oligoarticular juvenile idiopathic arthritis (JIA). Methods: This was a retrospective study. Clinical data on age, gender, and symptoms of joint swelling and pain were collected from 11 children with refractory oligoarticular JIA involving only knee joints admitted to Department of Rheumatism and Immunology of Children's Hospital, Capital Institute of Pediatrics from November 2019 to October 2020. The physician and parent-child evaluation of disease activity, the number of active joints, and the level of erythrocyte sedimentation rate (ESR) at different treatment time points were analyzed at every 4-week observation point after drug administration, and the non-parametric Kruskal-Wallis test was used to compare the differences in clinical evaluation indicators and changes in laboratory tests at different treatment times. The follow-up period was 6 months. Results: Among the 11 children, 5 were boys and 6 were girls. The age was 3.0 (2.8) years. All 11 children had symptoms of joint swelling and pain as well as limitation of movement. After 3 intra-articular injections of ADA, the joint symptoms of 11 children were better than before treatment; the joint symptoms of 7 children disappeared completely, and no recurrence occurred during the 6-month follow-up period. At different treatment times, physician and parent-child evaluation of disease activity, a gradual decrease in the number of active joints in the children, ESR, and juvenile arthritis disease activity score with 27 joints were all statistically significant (χ²=53.99, 59.37, 32.87, 40.07, 54.00, all P<0.001).No significant adverse drug reactions were observed in any of the 11 children during treatment and follow-up. Conclusion: Intra-articular injection of ADA in the treatment of refractory oligoarticular JIA has a significant effect in controlling joint symptoms and is relatively safe.

Forces involved in freeze-induced egg yolk gelation: Effects of various bond dissociation reagents on gel properties and protein structure changes

Urea, sodium dodecyl sulfate (SDS) and β-mercaptoethanol (2-ME) were used to monitor the roles of hydrogen bonds, hydrophobic interactions and disulfide bonds in frozen egg yolk. Yolk samples were prepared with a denaturant, and the textural characteristics, turbidity properties, protein patterns and structures were analysed. The results showed that SDS or 2-ME addition to egg yolk promoted its turbidity and texture properties, but urea changed the turbidity differently. SDS-PAGE results showed that yolk protein patterns with urea slightly reduced the amount of high molecular weight substances, whereas SDS and 2-ME addition increased the amount. ATR-FTIR spectroscopy revealed that the protein secondary structures changed from ordered structures to random coils. The texture properties were correlated with the protein secondary structure, especially β-sheets and β-turns. Thus, the three bond dissociation reagents induced protein denaturation. Hydrogen bonds were the critical force affecting frozen egg yolk gelation, followed by hydrophobic interactions and disulfide bonds.

Mechanistic insights into the improved properties of mayonnaise from the changes in protein structures of enzymatic modification-treated egg yolk

Heat treatment is an important step in mayonnaise production but can affect the quality of mayonnaise because thermal treatment can accelerate oil droplet coalescence. To resolve this issue, in this study, enzymatically modified egg yolks were applied to produce mayonnaise. Egg yolk hydrolyzed with 0.2% neutral protease could effectively produce mayonnaise with superior heat stability, and this effect was attributed to enzymatic modifications that increased the degree of amino acid ionization, the overall hydrophilicity and the ability to adsorb proteins. Moreover, electrophoresis and FT-IR results showed that the enzymatically modified egg yolk proteins had a smaller molecular weight and more flexible structure, which could also favor the improved properties. The study elucidated why mayonnaise prepared by enzymatic modification-treated egg yolk has better thermal stability.

Heat treatment is an important step in mayonnaise production but can affect the quality of mayonnaise because thermal treatment can accelerate oil droplet coalescence.

The mechanism of degradation of alizarin red by a white-rot fungus Trametes gibbosa

Background

Alizarin red (AR) is a typical anthraquinone dye, and the resulting wastewater is toxic and difficult to remove. A study showed that the white rot fungus Trametes gibbosa (T. gibbosa) can degrade dye wastewater by decolorization and has its own enzyme-producing traits.

Methods

In this study, transcriptome sequencing was performed after alizarin red treatment for 0, 3, 7, 10, and 14 h. The key pathways and key enzymes involved in alizarin red degradation were found to be through the analysis of KEGG and GO. The Glutathione S-transferase (GST), manganese peroxidase (MnP) and laccase activities of T. gibbosa treated with alizarin red for 0–14 h were detected. LC–MS and GC–MS analyses of alizarin red decomposition products after 7 h and 14 h were performed.

Results

The glutathione metabolic pathway ko00480, and the key enzymes GST, MnP, laccase and CYP450 were selected. Most of the genes encoding these enzymes were upregulated under alizarin red conditions. The GST activity increased 1.8 times from 117.55 U/mg prot at 0 h to 217.03 U/mg prot at 14 h. The MnP activity increased 2.9 times from 6.45 to 18.55 U/L. The laccase activity increased 3.7 times from 7.22 to 27.28 U/L. Analysis of the alizarin red decolourization rate showed that the decolourization rate at 14 h reached 20.21%. The main degradation intermediates were found to be 1,4-butene diacid, phthalic acid, 1,1-diphenylethylene, 9,10-dihydroanthracene, 1,2-naphthalene dicarboxylic acid, bisphenol, benzophenol-5,2-butene, acrylaldehyde, and 1-butylene, and the degradation process of AR was inferred. Overall, 1,4-butene diacid is the most important intermediate product produced by AR degradation.

Conclusions

The glutathione metabolic pathway was the key pathway for AR degradation. GST, MnP, laccase and CYP450 were the key enzymes for AR degradation. 1,4-butene diacid is the most important intermediate product. This study explored the process of AR biodegradation at the molecular and biochemical levels and provided a theoretical basis for its application in practical production.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12896-021-00720-8.

Differential effects of aquatic anaesthetics on the pharmacokinetics of antibiotics: Examples using florfenicol in Nile tilapia (Oreochromis niloticus)

Anaesthetics are commonly applied in pharmacokinetic (PK) studies to assure smooth handling of experimental procedures or to promote animal welfare. However, the influence of anaesthetics on the PK of co-administered drug is generally unknown but assumes ignorable. The goal of the study was to investigate the effect of tricaine methanesulfonate (MS-222), 2-phenoxyethanol (2-PE) and eugenol (EUG) on the PK of florfenicol (FF) in Nile tilapia. Twenty-eight fish were repeatedly exposed to 90 ppm EUG, 300 ppm MS-222 or 900 ppm 2-PE before FF oral administration (15 mg/kg) and each successive blood sampling. The serum concentration-time profiles were analysed by a 2-compartmental model, and the generated parameters in the control (without anaesthetic) and anaesthetic groups were statistically compared. The results demonstrated that the serum concentrations of each anaesthetic were similar at every FF sampling times (70 μg/ml for MS-222; 277 μg/ml for 2-PE; and 61 μg/ml for EUG). In comparison with the control group, the repeated use of MS-222 did not result in a statistical difference in most of the PK parameters. In contrast, the elimination half-lives of the 2-PE and EUG groups were significantly longer whereas the absorption and distribution half-lives of the 2-PE group were significantly shorter than the control, resulting in altered optimal dosages in the simulation modelling. Whether or not the numbers and extent of PK parameters change mitigate subsequent estimations of other PK-derived secondary values such as dosing regimen and withdrawal time remains to be elucidated, but the auxiliary use of anaesthetics in PK studies should not assume uninfluential.

Direct separation and purification of α-lactalbumin from cow milk whey by aqueous two-phase flotation of thermo-sensitive polymer/phosphate

BACKGROUND

α-lactalbumin (α-La) is of great interest to the industry as a result of its excellent functional properties and nutritional value. Aqueous two-phase flotation (ATPF) of thermo-sensitive polymer poly (ethylene glycol-ran-propylene glycol) monobutyl ether (UCON) and KH₂ PO₄ was applied to directly separate and purify α-La from milk whey, which was purposed to simplify the production process and reduced cost of production.

RESULTS

The effect of ATPF composition and operating parameters on the flotation efficiency (E) and purity of α-La were investigated. The optimal conditions included 2 min of premixing time, 30 mL min^-1 flow velocity and 20 min of flotation time, whereas the composition conditions comprised 35.0 mL 0.18 g mL^-1 phosphate solution (containing 10% (cow milk whey/salt solution, v/v) cow milk whey, 50 ppm defoamer and 2 g NaCl) and 5.0 mL of 40% (w/w) UCON solution. Under the optimal conditions, E of α-La was 95.67 ± 1.04% and purity of α-La was 98.78 ± 1.19%. UCON was recovered by a thermally-induced phase separation and reused in next ATPF process without reducing E of α-La. Purified α-La was characterized by several key technologies. The results indicated that α-La in cow milk whey could be directly separated and purified by the ATPF and the purity was satisfactory. Moreover, it was suggested there was no obvious structure difference between the α-La separated by ATPF and the α-La standard.

CONCLUSION

The present study enabled the recycling of UCON, providing an effective, economically viable and environmentally friendly approach for the separation and purification of protein. © 2021 Society of Chemical Industry.

Changes in Properties of Soy Protein Isolate Edible Films Stored at Different Temperatures: Studies on Water and Glycerol Migration

Plasticizers and the water migration of edible protein films during storage can result in changes in film properties, while specific changing processes need to be further explored. In this study, glycerol-plasticized soy protein isolate (SPI) films were stored at 25 °C, 4 °C, and -18 °C for 6 weeks (relative humidity (RH), 40-50%). The glycerol migration was monitored by the glycerol migration rate and differential scanning calorimetry (DSC). Water content, low-field nuclear magnetic resonance (LF-NMR), and thermogravimetric analysis (TGA) were used to analyze the water state. The results showed that significant pores and cracks were observed after storage at 25 °C. The proportion of bound water gradually increased, and the glycerol migration rate also reached 1.3% and 0.7% at 25 °C and 4 °C, respectively. The results proved that increasing the storage temperature accelerated the loss of water and glycerol, and decreased the mechanical properties of the SPI film.

General simultaneous motion estimation and image reconstruction (G-SMEIR)

To achieve better performance for 4D multi-frame reconstruction with the parametric motion model (MF-PMM), a general simultaneous motion estimation and image reconstruction (G-SMEIR) method is proposed. In G-SMEIR, projection domain motion estimation and image domain motion estimation are performed alternatively to achieve better 4D reconstruction. This method can mitigate the local optimum trapping problem in either domain. To improve computational efficiency, the image domain motion estimation is accelerated by adapting fast convergent algorithms and graphics processing unit (GPU) computing. The proposed G-SMEIR method is tested using a cone-beam computed tomography (CBCT) simulation study of 4D XCAT phantom at different dose levels and compared with 3D total variation-based reconstruction (3D TV), 4D reconstruction with image domain motion estimation (IM4D), and SMEIR. G-SMEIR shows strong denoising capability and achieves similar performance at regular dose and half dose. The root mean squared error (RMSE) of G-SMEIR is the best among the four methods and improved about 12% over SMEIR for all respiratory phase images at full dose. G-SMEIR also achieved the best structural similarity index (SSIM) values among all methods. More importantly, G-SMEIR leads to more than 40% improvement of the mean deviation from the phantom tumor motion over SMEIR. A preliminary patient CBCT image reconstruction also shows better image quality of G-SMEIR than that of the frame-by-frame reconstruction (3D TV) and MF-PMM either using image domain motion estimation (IM4D) or using projection domain motion estimation (SMEIR) alone. G-SMEIR with a flexible combination of image domain and projection domain motion estimation provides an effective tool for 4D tomographic reconstruction.

Recent Developments on gMicroMC: Transport Simulations of Proton and Heavy Ions and Concurrent Transport of Radicals and DNA

Mechanistic Monte Carlo (MC) simulation of radiation interaction with water and DNA is important for the understanding of biological responses induced by ionizing radiation. In our previous work, we employed the Graphical Processing Unit (GPU)-based parallel computing technique to develop a novel, highly efficient, and open-source MC simulation tool, gMicroMC, for simulating electron-induced DNA damages. In this work, we reported two new developments in gMicroMC: the transport simulation of protons and heavy ions and the concurrent transport of radicals in the presence of DNA. We modeled these transports based on electromagnetic interactions between charged particles and water molecules and the chemical reactions between radicals and DNA molecules. Various physical properties, such as Linear Energy Transfer (LET) and particle range, from our simulation agreed with data published by NIST or simulation results from other CPU-based MC packages. The simulation results of DNA damage under the concurrent transport of radicals and DNA agreed with those from nBio-Topas simulation in a comprehensive testing case. GPU parallel computing enabled high computational efficiency. It took 41 s to simultaneously transport 100 protons with an initial kinetic energy of 10 MeV in water and 470 s to transport 105 radicals up to 1 µs in the presence of DNA.