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1.
Ear Nose Throat J ; : 1455613241248119, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38647239

ABSTRACT

Objective: Warthin's tumors of the parotid gland can be safely observed. Definitive treatment usually requires parotidectomy under general anesthesia. The decision to operate on Warthin's tumors of the parotid gland can be complicated in patients who wish to avoid risks of surgery and general anesthesia. This systematic review explores the potential of radiofrequency ablation (RFA) as a minimally invasive alternative. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model was used to collect 3 relevant studies that focused on RFA treatment for Warthin's tumors. The cumulative averages for tumor size and cosmetic scores were then quantified for patients with Warthin's tumors who underwent RFA therapy. The PRISMA systematic review method was employed to the PubMed and EMBASE databases. The comprehensive search term "Warthin Tumor Treatment" yielded 1299 articles from the years 1955 to 2023, 3 of which met inclusion criteria and were then selected. Results: The 3 quantitative studies collectively assessed 37 patients with Warthin's tumors treated with RFA. Patients experienced an average tumor size reduction of 85.03% at 12 months post-RFA. There were minimal complications associated with RFA in these patients. Conclusion: This study suggests that RFA is an alternative to parotidectomy for the symptomatic treatment of Warthin's tumors. RFA procedures demonstrated substantial tumor size reduction with few complications. However, further meta-analysis and comparison with alternative treatments is warranted to establish RFA's role in treatment of Warthin's tumors. The study is limited by its reliance on only 2 databases and a lack of comprehensive examination of different RFA settings.

2.
Sci Rep ; 13(1): 1769, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36720967

ABSTRACT

Assembly is a critical step in the manufacturing process. Robotic assembly technology in automatic production lines has greatly improved the production efficiency. However, in assembly process, dynamic disturbances such as processing time change and advance delivery may occur, which cause the scheduling deviation. Traditional scheduling methods are not sufficient to meet the real-time and adaptive requirements in smart manufacturing. Digital twin (DT) has the characteristics of virtual-reality interaction and real-time mapping. In this paper, we propose a DT-based framework of task rescheduling for robotic assembly line (RAL) and its key methodologies, thus to realize the timely and dynamic adjustment of scheduling plan under uncertain interferences. First, a DT model of RAL task rescheduling composed of physical entity (PE), virtual entity (VE), and virtual-reality interaction mechanism is proposed. Then, a mathematical model is established. By analyzing the adaptive objective thresholds from the perspectives of event trigger and user demand trigger, a DT-driven multi-level (production unit level and line level) rescheduling strategy is proposed. Taking both the computing time and solution quality into consideration, the precedence graph is introduced to propose a rescheduling approach based on an improved discrete fireworks algorithm. Finally, the effectiveness of the proposed model and approach are verified by task scheduling experiments of RAL.

3.
ACS Omega ; 7(28): 24688-24694, 2022 Jul 19.
Article in English | MEDLINE | ID: mdl-35874255

ABSTRACT

A novel NaF phase change microcapsule with a carbon shell (NaF@C microcapsule) was prepared by a simple approach. The carbon shell was synthesized by carbonization of a resole-type phenolic resin shell, which was encapsulated onto the surface of NaF particles by a simple phase separation process induced by tetraethoxysilane. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis were used to characterize the morphology, composition, crystal phase, and thermal properties of the microcapsules. The size of the NaF@C microcapsule was 3-5 µm with a core-shell structure. DSC results showed that the melting point of the prepared NaF@C microcapsule was 988 °C, and the enthalpy value was 192 J/g. The prepared NaF@C microcapsules retained the powder morphology after 30 times of heat treatment at 1100 °C, with no NaF leakage detected, and the micromorphology remained stable, presenting good thermal stability. The NaF@C microcapsules can be used in the fields of thermal protection and thermal management in extreme high-temperature environments such as aerospace and solar energy.

4.
Front Genet ; 13: 929716, 2022.
Article in English | MEDLINE | ID: mdl-35846143

ABSTRACT

Histone methylation shapes the epigenetic configuration and adjusts multiple fundamental nuclear processes, including transcription, cell cycle control and DNA repair. The absence of histone demethylase LSD1/SPR-5 leads to progressive fertility defects as well as a reduction in brood size. Similarly, C. elegans LSD2 homolog AMX-1 has been implicated in regulating H3K4me2 and maintaining interstrand crosslinks (ICL) susceptibility. However, the mechanisms of how lack of AMX-1 induces sterility have not been addressed so far. This study investigated the histone demethylase AMX-1 in C. elegans and uncovered how amx-1 contributes to sterility in a p53/CEP-1 dependent manner. We show that while sterility in spr-5 mutants exhibited progressive over generations, amx-1 mutants displayed non-transgenerational fertility defects. Also, amx-1 mutants exhibited a reduced number of sperms and produced low brood size (LBS) or sterile worms that retain neither sperms nor germline nuclei, suggesting that fertility defects originated from germline development failure. Surprisingly, sterility exhibited in amx-1 was mediated by p53/CEP-1 function. Consistent with this result, upregulation of Piwi expression in amx-1 mutants suggested that AMX-1 is essential for germline development by regulating Piwi gene expressions. We propose that AMX-1 is required for proper Piwi expression and transposon silencing in a p53/CEP-1 dependent manner; thus, the absence of AMX-1 expression leads to defective meiotic development and sterility. This study elucidates how LSD2/AMX-1 contributes to sterility, therefore, expanding the boundaries of histone demethylase function.

5.
ACS Omega ; 7(2): 1908-1913, 2022 Jan 18.
Article in English | MEDLINE | ID: mdl-35071881

ABSTRACT

Traditional high-temperature energy utilization systems employ conventional solid sensible heat storage (SHS) for energy storage. Latent heat storage (LHS) serves as a surrogate for energy storage as opposed to the SHS system due to the presence of phase-change materials (PCMs). In this paper, we report the production and characterization of Al microencapsulated PCM (MEPCM) through a simple one-step self-sacrificial oxidation fabrication process, where the core-shell type microencapsulated with Al microsphere (mean diameter 35 µm, melting temperature 669 °C) acted as the core (PCM) and Al2O3 as the shell. During the oxidation process, the surface layer of the Al microparticle was sacrificed to form a stable Al2O3 shell, which was only about 50 nm thick presented by means of a focused ion beam (FIB). In terms of the analyses of FIB and X-ray photoelectron spectroscopy (XPS), it is apparent that Al2O3 is successfully formed on the surface of Al microparticles, which can keep a stable solid shell structure during solid-liquid phase transitions. The latent heat of MEPCM was 310.4 kJ/kg, and the melting temperature was 668 °C. Thus, the one-step self-sacrificial heat-oxidation technique can lead to better commercialization and environmental friendliness of next-generation LHS-based high-temperature thermal energy storage materials.

6.
PLoS Genet ; 17(7): e1009715, 2021 07.
Article in English | MEDLINE | ID: mdl-34329293

ABSTRACT

Histone methylation is dynamically regulated to shape the epigenome and adjust central nuclear processes including transcription, cell cycle control and DNA repair. Lysine-specific histone demethylase 2 (LSD2) has been implicated in multiple types of human cancers. However, its functions remain poorly understood. This study investigated the histone demethylase LSD2 homolog AMX-1 in C. elegans and uncovered a potential link between H3K4me2 modulation and DNA interstrand crosslink (ICL) repair. AMX-1 is a histone demethylase and mainly localizes to embryonic cells, the mitotic gut and sheath cells. Lack of AMX-1 expression resulted in embryonic lethality, a decreased brood size and disorganized premeiotic tip germline nuclei. Expression of AMX-1 and of the histone H3K4 demethylase SPR-5 is reciprocally up-regulated upon lack of each other and the mutants show increased H3K4me2 levels in the germline, indicating that AMX-1 and SPR-5 regulate H3K4me2 demethylation. Loss of AMX-1 function activates the CHK-1 kinase acting downstream of ATR and leads to the accumulation of RAD-51 foci and increased DNA damage-dependent apoptosis in the germline. AMX-1 is required for the proper expression of mismatch repair component MutL/MLH-1 and sensitivity against ICLs. Interestingly, formation of ICLs lead to ubiquitination-dependent subcellular relocalization of AMX-1. Taken together, our data suggest that AMX-1 functions in ICL repair in the germline.


Subject(s)
DNA Repair/genetics , Histone Demethylases/metabolism , Animals , Animals, Genetically Modified , Caenorhabditis elegans , Caenorhabditis elegans Proteins , Cell Nucleus/metabolism , DNA Damage/genetics , DNA Repair/physiology , Germ Cells/metabolism , Histone Demethylases/physiology , Histones/genetics , Methylation , Protein Processing, Post-Translational/genetics , Ubiquitination
7.
3 Biotech ; 10(8): 350, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32728517

ABSTRACT

A variety of techniques, including CRISPR-Cas9 genome editing, have been developed to produce genetically modified cell lines and animal models. In many cases, the success of the genome-editing techniques is dependent on the quality of the introduced DNA. However, the preparation of high-quality plasmids required for small-scale microinjection has not been explored. Here, we compared various types of plasmid preparation methods for their microinjection proficiency and developed an efficient and affordable plasmid mini preparation method suitable for Caenorhabditis elegans microinjection. By combining the advantages of Triton X-114 and column-based mini preparation (hence, we named it TXC), the new TXC method was affordable, efficient, and equivalent to expensive plasmid midiprep method based on microinjection efficiency. Besides, TXC was compatible with general molecular biology grade reactions and worked proficiently for different types of plasmids.

8.
J Agric Food Chem ; 65(4): 900-907, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-28064487

ABSTRACT

The potential application of Pickering high-internal phase emulsions (HIPEs) in the food and pharmaceutical industries has yet to be fully developed. Herein, we synthesized fairly monodisperse, nontoxic, autofluorescent gelatin particles for use as sole stabilizers for fabricating oil-in-water (O/W) HIPEs in an effort to improve the protection and bioaccessibility of entrapped ß-carotene. Our results showed that the concentration of gelatin particles determined the formation, microstructure, droplet size distribution, and digestion profile of the HIPEs. For storage stability, the retention of ß-carotene in HIPEs was significantly higher than in dispersion in bulk oil, even after storage for 27 days. In addition, in vitro digestion experiments indicated that the bioaccessibility of ß-carotene was improved 5-fold in HIPEs. This study will help establish a correlation between the physicochemical properties of gelatin particle-stabilized HIPEs with their applications in the oral delivery of bioactive nutraceuticals.


Subject(s)
Digestion , Drug Carriers/chemistry , Gastrointestinal Tract/metabolism , Gelatin/chemistry , beta Carotene/metabolism , Drug Carriers/metabolism , Drug Delivery Systems , Emulsions/metabolism , Gelatin/metabolism , Humans , Models, Biological , Particle Size , beta Carotene/chemistry
9.
PLoS One ; 10(2): e0117470, 2015.
Article in English | MEDLINE | ID: mdl-25658953

ABSTRACT

A novel exonuclease, designated as MszExo I, was cloned from Methylocaldum szegediense, a moderately thermophilic methanotroph. It specifically digests single-stranded DNA in the 3' to 5' direction. The protein is composed of 479 amino acids, and it shares 47% sequence identity with E. coli Exo I. The crystal structure of MszExo I was determined to a resolution of 2.2 Å and it aligns well with that of E. coli Exo I. Comparative studies revealed that MszExo I and E. coli Exo I have similar metal ion binding affinity and similar activity at mesophilic temperatures (25-47°C). However, the optimum working temperature of MszExo I is 10°C higher, and the melting temperature is more than 4°C higher as evaluated by both thermal inactivation assays and DSC measurements. More importantly, two thermal transitions during unfolding of MszExo I were monitored by DSC while only one transition was found in E. coli Exo I. Further analyses showed that magnesium ions not only confer structural stability, but also affect the unfolding of MszExo I. MszExo I is the first reported enzyme in the DNA repair systems of moderately thermophilic bacteria, which are predicted to have more efficient DNA repair systems than mesophilic ones.


Subject(s)
Bacterial Proteins/chemistry , Exodeoxyribonucleases/chemistry , Methylococcaceae/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cloning, Molecular , Crystallography, X-Ray , DNA Repair/physiology , Exodeoxyribonucleases/genetics , Exodeoxyribonucleases/metabolism , Hot Temperature , Methylococcaceae/genetics
10.
Fibrogenesis Tissue Repair ; 6(1): 4, 2013 Feb 04.
Article in English | MEDLINE | ID: mdl-23374750

ABSTRACT

BACKGROUND: Crew members on space missions inevitably are exposed to low background radiation and can receive much higher doses during solar particle events (SPE) that consist primarily of protons. Ionizing radiation could cause lung pathologies. Cell adhesion molecules (CAM) are believed to participate in fibrogenesis. Interactions between CAM and extracellular matrix (ECM) affect epithelial repair mechanisms in the lung. However, there are very limited data on biological effects of protons on normal lung tissue. Numerous reports have shown that exposure to low-dose/low-dose-rate (LDR) radiation can result in radioadaptation that renders cells more resistant to subsequent acute radiation. The goal of this study was to compare expression of genes associated with ECM and CAM, as well as critical profibrotic mediators, in mouse lungs after acute irradiation with photons and protons, and also determine whether pre-exposure to LDR γ-rays induces an adaptive effect. RESULTS: Overall, a marked difference was present in the proton vs. photon groups in gene expression. When compared to 0 Gy, more genes were affected by protons than by photons at both time points (11 vs. 6 on day 21 and 14 vs. 8 on day 56), and all genes affected by protons were upregulated. Many genes were modulated by LDR γ-rays when combined with photons or protons. Col1a1, mmp14, and mmp15 were significantly upregulated by all radiation regimens on day 21. Similarly, the change in expression of profibrotic proteins was also detected after acute and combination irradiation. CONCLUSION: These data show that marked differences were present between acutely delivered protons and photons in modulating genes, and the effect of protons was more profound than that of photons. Pre-exposure to LDR γ-rays 'normalized' some genes that were modified by acute irradiation.

11.
Radiat Res ; 176(5): 553-64, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21854213

ABSTRACT

The goal of this study was to compare the effects of acute 2 Gy irradiation with photons (0.8 Gy/min) or protons (0.9 Gy/min), both with and without pre-exposure to low-dose/low-dose-rate γ rays (0.01 Gy at 0.03 cGy/h), on 84 genes involved in stem cell differentiation or regulation in mouse lungs on days 21 and 56. Genes with a ≥1.5-fold difference in expression and P < 0.05 compared to 0 Gy controls are emphasized. Two proteins specific for lung stem cells/progenitors responsible for local tissue repair were also compared. Overall, striking differences were present between protons and photons in modulating the genes. More genes were affected by protons than by photons (22 compared to 2 and 6 compared to 2 on day 21 and day 56, respectively) compared to 0 Gy. Preirradiation with low-dose-rate γ rays enhanced the acute photon-induced gene modulation on day 21 (11 compared to 2), and all 11 genes were significantly downregulated on day 56. On day 21, seven genes (aldh2, bmp2, cdc2a, col1a1, dll1, foxa2 and notch1) were upregulated in response to most of the radiation regimens. Immunoreactivity of Clara cell secretory protein was enhanced by all radiation regimens. The number of alveolar type 2 cells positive for prosurfactant protein C in irradiated groups was higher on day 56 (12.4-14.6 cells/100) than on day 21 (8.5-11.2 cells/100) (P < 0.05). Taken together, these results showed that acute photons and protons induced different gene expression profiles in the lungs and that pre-exposure to low-dose-rate γ rays sometimes had modulatory effects. In addition, proteins associated with lung-specific stem cells/progenitors were highly sensitive to radiation.


Subject(s)
Cell Differentiation/genetics , Cell Differentiation/radiation effects , Lung/cytology , Lung/metabolism , Photons/adverse effects , Protons/adverse effects , Transcriptome/radiation effects , Adult Stem Cells/cytology , Adult Stem Cells/metabolism , Adult Stem Cells/radiation effects , Animals , Biomarkers/metabolism , Dose-Response Relationship, Radiation , Female , Lung/radiation effects , Mice , Mice, Inbred C57BL , Organ Specificity , Time Factors
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