bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Reprogramming of Castration-Resistant Prostate Cancer Cells as a Response to Chemotherapy
Authors: Petrella Greta , Corsi Francesca , Ciufolini Giorgia , Germini Sveva , Capradossi Francesco , Pelliccia Andrea , Torino Francesco , Ghibelli Lina , Cicero Daniel Oscar
Published: January 2023

Prostate cancer at the castration-resistant stage (CRPC) is a leading cause of death among men due to resistance to anticancer treatments, including chemotherapy. We set up an in vitro model of therapy-induced cancer repopulation and acquired cell resistance (CRAC) on etoposide-treated CRPC PC3 cells, witnessing therapy-induced epithelial-to-mesenchymal-transition (EMT) and chemoresistance among repopulating cells. Here, we explore the metabolic changes leading to chemo-induced CRAC, measuring the exchange rates cell/culture medium of 36 metabolites via Nuclear Magnetic Resonance spectroscopy. We studied the evolution of PC3 metabolism throughout recovery from etoposide, encompassing the degenerative, quiescent, and repopulating phases. We found that glycolysis is immediately shut off by etoposide, gradually recovering together with induction of EMT and repopulation. Instead, OXPHOS, already high in untreated PC3, is boosted by etoposide to decline afterward, though stably maintaining values higher than control. Notably, high levels of EMT, crucial in the acquisition of chemoresistance, coincide with a strong acceleration of metabolism, especially in the exchange of principal nutrients and their end products. These results provide novel information on the energy metabolism of cancer cells repopulating from cytotoxic drug treatment, paving the way for uncovering metabolic vulnerabilities to be possibly pharmacologically targeted and providing novel clinical options for CRPC.
Improved Weighted Non-Local Mean Filtering Algorithm for Laser Image Speckle Suppression
Authors: Cheng Jin , Xie Yibo , Zhou Shun , Lu Anjiang , Peng Xishun , Liu Weiguo
Published: January 2023

Laser speckle noise caused by coherence between lasers greatly influences the produced image. In order to suppress the effect of laser speckles on images, in this paper we set up a combination of a laser-structured light module and an infrared camera to acquire laser images, and propose an improved weighted non-local mean (IW-NLM) filtering method that adopts an SSI-based adaptive h-solving method to select the optimal h in the weight function. The analysis shows that the algorithm not only denoises the laser image but also smooths pixel jumps in the image, while preserving the image details. The experimental results show that compared with the original laser image, the equivalent number of looks (ENL) index of the IW-NLM filtered image improved by 0.80%. The speckle suppression index (SSI) of local images dropped from 4.69 to 2.55%. Compared with non-local mean filtering algorithms, the algorithm proposed in this paper is an improvement and provides more accurate data support for subsequent image processing analysis.
A Bias Drift Suppression Method Based on ICELMD and ARMA-KF for MEMS Gyros
Authors: Feng Lihui , Du Le , Guo Junqiang , Cui Jianmin , Lu Jihua , Zhu Zhengqiang , Wang Lijuan
Published: January 2023

The applications of Micro-Electro-Mechanical-System (MEMS) gyros in inertial navigation system is gradually increasing. However, the random drift of gyro deteriorates the system performance which restricting the applications of high precision. We propose a bias drift compensation model based on two-fold Interpolated Complementary Ensemble Local Mean Decomposition (ICELMD) and autoregressive moving average-Kalman filtering (ARMA-KF). We modify CELMD into ICELMD, which is less complicated and overcomes the endpoint effect. Further, the ICELMD is combined with ARMA-KF to separate and simplify the preprocessed signal, resulting improved denoising performance. In the model, the abnormal noise is removed in preprocess by 2σ criterion with ICELMD. Then, continuous mean square error (CMSE) and Permutation Entropy (PE) are both applied to categorize the preprocessed signal into noise, mixed and useful components. After abandon the noise components and denoise the mixed components by ARMA-KF, we rebuild the noise suppression signal of MEMS gyro. Experiments are carried out to validate the proposed algorithm. The angle random walk of gyro decreases from 2.4156∘/h to 0.0487∘/h, the zero bias instability lowered from 0.3753∘/h to 0.0509∘/h. Further, the standard deviation and the variance are greatly reduced, indicating that the proposed method has better suppression effect, stability and adaptability.
A Practical Multi-Stage Grasp Detection Method for Kinova Robot in Stacked Environments
Authors: Dong Xuefeng , Jiang Yang , Zhao Fengyu , Xia Jingtao
Published: January 2023

Grasp detection takes on a critical significance for the robot. However, detecting object positions and corresponding grasp positions in a stacked environment can be quite difficult for a robot. Based on this practical problem, in order to achieve more accurate object position detection and grasp position detection, a new method called MMD (Multi-stage network for multi-object grasp detection algorithm) is proposed in this paper. MMD covers two parts, including the feature extractor and the multi-stage object predictor. The feature extractor refers to a deep convolutional neural network that can generate shared feature layers as well as the initial ROIs (region of interest). A multi-stage refiner serves as the multi-stage object predictor, which continuously regresses the initial ROI to obtain more accurate object detection and grasping detection results. Ablation experiments show that the proposed MMD has better grasp detection performance. The specific performance is that the recognition precision achieves a state-of-the-art 76.71% mAPg on the VMRD dataset. Moreover, test experiments demonstrate the feasibility of our method on the Kinova robot.
On the Behavior of Honeycomb, Grid and Triangular PLA Structures under Symmetric and Asymmetric Bending
Authors: Cojocaru Vasile , Frunzaverde Doina , Miclosina Calin-Octavian
Published: January 2023

Additive manufacturing technologies enable the production of components with lightweight cores, by means of infills with various patterns and densities. Together with reduced mass and material consumption, infill geometries must ensure that strength and stiffness conditions are fulfilled. For the proper correlation of the infill type with the loading case of the part, the mechanical behavior of the infill along all three principal axes of inertia has to be known. In this paper, the behavior in symmetric and asymmetric bending of three infill geometries, commonly used in 3D printing processes (honeycomb, grid and triangles) is analyzed. The variations of deflections as a function of force orientation are presented, showing that honeycomb and triangular structures exhibit similar behaviors along the Y and Z principal axes of inertia. Furthermore, the displacements obtained for the three types of structures are compared, in relation to the consumed volume of material. The larger displacements of the grid structure compared to the honeycomb and triangular structures are highlighted.
Multi-Grid Capacitive Transducers for Measuring the Surface Profile of Silicon Wafers
Authors: Zheng Panpan , Cai Bingyang , Zhu Tao , Yu Li , Wu Wenjie , Tu Liangcheng
Published: January 2023

The measurements of wafers’ surface profile are crucial for safeguarding the fabrication quality of integrated circuits and MEMS devices. The current techniques measure the profile mainly by moving a capacitive or optical spacing sensing probe along multiple lines, which is high-cost and inefficient. This paper presents the calculation, simulation and experiment of a method for measuring the surface profile with arrayed capacitive spacing transducers. The calculation agreed well with the simulation and experiment. Finally, the proposed method was utilized for measuring the profile of a silicon wafer. The result is consistent with that measured by a commercial instrument. As a movement system is not required, the proposed method is promising for industry applications with superior cost and efficiency to the existing technology.
Achieving Self-Supported Hierarchical Cu(OH)2/Nickel–Cobalt Sulfide Electrode for Electrochemical Energy Storage
Authors: Lv Sa , Shang Wenshi , Chi Yaodan , Wang Huan , Chu Xuefeng , Wu Boqi , Geng Peiyu , Wang Chao , Yang Jia , Cheng Zhifei , Yang Xiaotian
Published: January 2023

Herein, nickel–cobalt sulfide (NCS) nanoflakes covering the surface of Cu(OH)2 nanorods were achieved by a facile two-step electrodeposition strategy. The effect of CH4N2S concentration on formation mechanism and electrochemical behavior is investigated and optimized. Thanks to the synergistic effect of the selected composite components, the Cu(OH)2/NCS composite electrode can deliver a high areal specific capacitance (Cs) of 7.80 F cm−2 at 2 mA cm−2 and sustain 5.74 F cm−2 at 40 mA cm−2. In addition, coulombic efficiency was up to 84.30% and cyclic stability remained 82.93% within 5000 cycles at 40 mA cm−2. This innovative work provides an effective strategy for the design and construction of hierarchical composite electrodes for the development of energy storage devices.
Bacterial Profiles of Brain in Downer Cattle with Unknown Etiology
Authors: Park Yeong-Jun , Kang Gi-Ung , Jeong Minsoo , Singh Vineet , Kim Jongho , Lee Kyunghyun , Choi Eun-Jin , Kim Heui-Jin , Lee Seungjun , Lee Sook-Young , Oem Jae-Ku , Shin Jae-Ho
Published: January 2023

Downer cow can be caused by muscular paralysis, neurological damage, metabolic disorder, and/or the complication of microbial infection. However, downer cow with unknown etiology is issued because of the non-detection of its bacterial etiological agent. In this study, differences in the bacterial community in brain tissues between downer cattle with unknown etiology and healthy slaughtered cattle are investigated. Bacterial diversity and representative genera between downer and normal cattle were significantly different (p < 0.05). There are significant differences in representative genera of downer and normal cattle, especially the significance, fold change, and area under the receiver operating characteristic curve score (p < 0.05). Furthermore, the prediction of functional genes in brain microbiota between the downer and normal cattle revealed differences in the cluster of orthologous gene categories, such as lipid transport and metabolism, secondary metabolite biosynthesis, and signal transduction (p < 0.05). This study revealed a significant difference in microbiota between the downer and normal cattle. Thus, we demonstrate that representative genera from downer cattle through 16S rRNA gene amplicon sequencing and microbiota analysis have the potential as candidates for bacterial etiological agents for downer cow.
Diversity of Mixotrophic Neutrophilic Thiosulfate- and Iron-Oxidizing Bacteria from Deep-Sea Hydrothermal Vents
Authors: He Yang , Zeng Xiang , Xu Fei , Shao Zongze
Published: January 2023

At deep-sea hydrothermal vents, sulfur oxidation and iron oxidation are of the highest importance to microbial metabolisms, which are thought to contribute mainly in chemolithoautotrophic groups. In this study, 17 mixotrophic neutrophilic thiosulfate- and iron-oxidizing bacteria were isolated from hydrothermal fields on the Carlsberg Ridge in the Indian Ocean, nine to the γ-proteobacteria (Halomonas (4), Pseudomonas (2), Marinobacter (2), and Rheinheimera (1)), seven to the α-proteobacteria (Thalassospira, Qipengyuania, Salipiger, Seohaeicola, Martelella, Citromicrobium, and Aurantimonas), and one to the Actinobacteria (Agromyces), as determined by their 16S rRNA and genome sequences. The physiological characterization of these isolates revealed wide versatility in electron donors (Fe(II) and Mn(II), or thiosulfate) and a variety of lifestyles as lithotrophic or heterotrophic, microaerobic, or anaerobic. As a representative strain, Pseudomonas sp. IOP_13 showed its autotrophic gowth from 105 cells/ml to 107 cells/ml;carbon dioxide fixation capacity with the δ13CVPDB in the biomass increased from −27.42‰ to 3460.06‰; the thiosulfate-oxidizing ability with produced SO42− increased from 60 mg/L to 287 mg/L; and the iron-oxidizing ability with Fe(II) decreased from 10 mM to 5.2 mM. In addition, iron-oxide crust formed outside the cells. Gene coding for energy metabolism involved in possible iron, manganese, and sulfur oxidation, and denitrification was identified by their genome analysis. This study sheds light on the function of the mixotrophic microbial community in the iron/manganese/sulfur cycles and the carbon fixation of the hydrothermal fields.
Enterococcus faecalis NADH Peroxidase-Defective Mutants Stain Falsely in Colony Zymogram Assay for Extracellular Electron Transfer to Ferric Ions
Authors: Hederstedt Lars
Published: January 2023

Enterococcus faecalis cells can reduce ferric ions and other electron acceptors by extracellular electron transfer (EET). To find mutants with enhanced or defective EET, strain OG1RF with random transposon insertions in the chromosome was screened for ferric reductase activity by colony zymogram staining using the chromogenic ferrous-chelating compound Ferrozine. The screen revealed npr, eetB, and ndh3 mutants. The aberrant ferric reductase phenotype of Npr (NADH peroxidase)-defective mutants was found to be a property of colonies and not apparent with washed cells grown in liquid culture. EetB- and Ndh3-defective mutants, in contrast, consistently showed low ferric reductase activity. It is concluded that colony zymogram staining for ferric reductase activity using Ferrozine can be misleading, especially through false negative results. It is suggested that hydrogen peroxide produced in the colony quenches the zymogram staining. In addition, it is demonstrated that the negative effect of heme on EET to ferric ion in E. faecalis is relieved by cytochrome bd deficiency. The findings can help to identify bacteria with EET ability and contribute to our understanding of EET in Gram-positive bacteria and the physiology of E. faecalis.
Characteristics of Soil Physicochemical Properties and Microbial Community of Mulberry (Morus alba L.) and Alfalfa (Medicago sativa L.) Intercropping System in Northwest Liaoning
Authors: Li Muzi , Wei Yawei , Yin You , Zhu Wenxu , Bai Xuejiao , Zhou Yongbin
Published: January 2023

Medicinal plant intercropping is a new intercropping method. However, as a new intercropping model, the influence of intercropping of alfalfa on microorganisms has not been clarified clearly. In this study, the composition and diversity of microbial communities in alfalfa intercropping were studied, and the differences of bacterial and fungal communities and their relationships with environmental factors are discussed. Intercropping significantly decreased soil pH and significantly increased soil total phosphorus (TP) content, but did not increase soil total carbon (TC) and total nitrogen (TN). Intercropping can increase the relative abundance of Actinobacteria and reduce the relative abundance of Proteobacteria in soil. The relative abundance and diversity of bacteria were significantly correlated with soil pH and TP, while the diversity of fungi was mainly correlated with TC, TN and soil ecological stoichiometry. The bacterial phylum was mainly related to pH and TP, while the fungal phylum was related to TC, TN, C: P and N: P. The present study revealed the stoichiometry of soil CNP and microbial community characteristics of mulberry-alfalfa intercropping soil, clarified the relationship between soil stoichiometry and microbial community composition and diversity, and provided a theoretical basis for the systematic management of mulberry-alfalfa intercropping in northwest Liaoning.
Virulence Factors of the Periodontal Pathogens: Tools to Evade the Host Immune Response and Promote Carcinogenesis
Authors: Shahoumi Linah A. , Saleh Muhammad H. A. , Meghil Mohamed M.
Published: January 2023

Periodontitis is the most common chronic, inflammatory oral disease that affects more than half of the population in the United States. The disease leads to destruction of the tooth-supporting tissue called periodontium, which ultimately results in tooth loss if uncured. The interaction between the periodontal microbiota and the host immune cells result in the induction of a non-protective host immune response that triggers host tissue destruction. Certain pathogens have been implicated periodontal disease formation that is triggered by a plethora of virulence factors. There is a collective evidence on the impact of periodontal disease progression on systemic health. Of particular interest, the role of the virulence factors of the periodontal pathogens in facilitating the evasion of the host immune cells and promotion of carcinogenesis has been the focus of many researchers. The aim of this review is to examine the influence of the periodontal pathogens Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis), and Fusobacterium nucleatum (F. nucleatum) in the modulation of the intracellular signaling pathways of the host cells in order to evade the host immune response and interfere with normal host cell death and the role of their virulence factors in this regard.
Are There Any Changes in the Causative Microorganisms Isolated in the Last Years from Hip and Knee Periprosthetic Joint Infections? Antimicrobial Susceptibility Test Results Analysis
Authors: Roman Mihai Dan , Bocea Bogdan-Axente , Ion Nicolas-Ionut-Catalin , Vorovenci Andreea Elena , Dragomirescu Dan , Birlutiu Rares-Mircea , Birlutiu Victoria , Fleaca Sorin Radu
Published: January 2023

Background: PJIs following total hip and knee arthroplasty represent severe complications with broad implications, and with significant disability, morbidity, and mortality. To be able to provide correct and effective management of these cases, an accurate diagnosis is needed. Classically, acute PJIs are characterized by a preponderance of virulent microorganisms, and chronic PJIs are characterized by a preponderance of less-virulent pathogens like coagulase-negative staphylococci or Cutibacterium species. This paper aims to analyze if there are any changes in the causative microorganisms isolated in the last years, as well as to provide a subanalysis of the types of PJIs. Methods: In this single-center study, we prospectively included all retrospectively consecutive collected data from patients aged over 18 years that were hospitalized from 2016 through 2022, and patients that underwent a joint arthroplasty revision surgery. A standardized diagnostic protocol was used in all cases, and the 2021 EBJIS definition criteria for PJIs was used. Results: 114 patients were included in our analysis; of them, 67 were diagnosed with PJIs, 12 were acute/acute hematogenous, and 55 were chronic PJIs. 49 strains of gram-positive aerobic or microaerophilic cocci and 35 gram-negative aerobic bacilli were isolated. Overall, Staphylococcus aureus was the most common isolated pathogen, followed by coagulase-negative staphylococci (CoNS). All cases of acute/acute hematogenous PJIs were caused by gram-positive aerobic or microaerophilic cocci pathogens. Both Staphylococcus epidermidis and methicillin-resistant S. aureus were involved in 91.66% of the acute/acute hematogenous PJIs cases. 21.8% of the chronic PJIs cases were caused by pathogens belonging to the Enterobacterales group of bacteria, followed by the gram-negative nonfermenting bacilli group of bacteria, which were involved in 18.4% of the cases. 12 chronic cases were polymicrobial. Conclusion: Based on our findings, empiric broad-spectrum antibiotic therapy in acute PJIs could be focused on the bacteria belonging to the gram-positive aerobic or microaerophilic cocci, but the results should be analyzed carefully, and the local resistance of the pathogens should be taken into consideration.
Optimization of Transposon Mutagenesis Methods in Pseudomonas antarctica
Authors: Kim Sangha , Lee Changhan
Published: January 2023

Pseudomonas is a widespread genus in various host and environmental niches. Pseudomonas exists even in extremely cold environments such as Antarctica. Pseudomonas antarctica is a psychrophilic bacterium isolated from Antarctica. P. antarctica is also known to produce antimicrobial substances. Although P. antarctica can provide insight into how bacteria have adapted to low temperatures and has significant potential for developing novel antimicrobial substances, progress in genetic and molecular studies has not been achieved. Transposon mutagenesis is a useful tool to screen genes of interest in bacteria. Therefore, we attempted for the first time in P. antarctica to generate transposon insertion mutants using the transfer of a conjugational plasmid encoding a transposon. To increase the yield of transposon insertion mutants, we optimized the methods, in terms of temperature for conjugation, the ratio of donor and recipient during conjugation, and the concentration of antibiotics. Here, we describe the optimized methods to successfully generate transposon insertion mutants in P. antarctica.
Rock Magnetic Results from the Early Ordovician Limestone Rocks in the Northern Qaidam Block, Tibetan Plateau
Authors: Deng Xiaohong , Zhou Yanan , Wang Teng , Cheng Xin , Wei Bitian , Jiang Nan , Zhang Dongmeng , Li Teng , Lan Shuqi , Xing Longyun , Wu Hanning
Published: January 2023

The early Ordovician location of the Qaidam Block remains unclear, mainly due to the sparse paleomagnetic data to quantitatively determine the coeval position. The early Ordovician limestone is widespread in the northern Qaidam Block providing an ideal window to obtain a paleomagnetic result. The results derived from the limestone are, however, frequently constrained by the hydrothermal fluid activities after the strata formed and complex magnetic minerals in the samples. Therefore, systematic petrological and rock magnetic studies were conducted to identify the content and composition of magnetic minerals in the limestone samples from the early Ordovician Duoquanshan Formation in the northern Qaidam Block. The rock magnetic and petrologic results show that the magnetic carriers in the limestone samples are dominated by magnetite with a small amount of pyrrhotite, goethite, and hematite. These results are consistent with the characteristics of stepwise demagnetization. Combined with the results published previously, the secondary remanence component carried by pyrrhotite might be produced by thermal fluid or magma active by the multiple Tethys evolution.
Electrification Alternatives for Open Pit Mine Haulage
Authors: Bao Haiming , Knights Peter , Kizil Mehmet , Nehring Micah
Published: January 2023

Truck-Shovel (TS) systems are the most common mining system currently used in large surface mines. They offer high productivity combined with the flexibility to be rapidly relocated and to adjust load/haul capacity and capital expenditure according to market conditions. As the world moves to decarbonise as part of the transition to net zero emission targets, it is relevant to examine options for decarbonising the haulage systems in large surface mines. In-Pit Crushing and Conveying (IPCC) systems offer a smaller environmental footprint regarding emissions, but they are associated with a number of limitations related to high initial capital expenditure, capacity limits, mine planning and inflexibility during mine operation. Among the emerging technological options, innovative Trolley Assist (TA) technology promises to reduce energy consumption for lower carbon footprint mining systems. TA systems have demonstrated outstanding potential for emission reduction from their application cases. Battery and energy recovery technology advancements are shaping the evolution of TAs from diesel-electric truck-based patterns toward purely electrified BT ones. Battery Trolley (BT) systems combined with autonomous battery-electric trucks and Energy Recovery Systems (ERSs) are novel and capable of achieving further significant emission cuts for surface mining operations associated with safety, energy saving and operational improvements. This article reviews and compares electrification alternatives for large surface mines, including IPCC, TA and BT systems. These emerging technologies provide opportunities for mining companies and associated industries to adopt zero-emission solutions and help transition to an intelligent electric mining future.
Current Practices for Preventive Maintenance and Expectations for Predictive Maintenance in East-Canadian Mines
Authors: Robatto Simard Simon , Gamache Michel , Doyon-Poulin Philippe
Published: January 2023

Preventive maintenance practices have been proven to reduce maintenance costs in many industries. In the mining industry, preventive maintenance is the main form of maintenance, especially for mobile equipment. With the increase of sensor data and the installation of wireless infrastructure within underground mines, predictive maintenance practices are beginning to be applied to the mining equipment maintenance process. However, for the transition from preventive to predictive maintenance to succeed, researchers must first understand the maintenance process implemented in mines. In this paper, we conducted interviews with 15 maintenance experts from 7 mining sites (6 gold, 1 diamond) across East-Canada to investigate the maintenance planning process currently implemented in Canadian mines. We documented experts’ feedback on the process, their expectations regarding the introduction of predictive maintenance in mining, and the usability of existing computerized maintenance management software (CMMS). From our results, we compiled a summary of actual maintenance practices and showed how they differ from theoretical practices. Finally, we list the Key Performance Indicators (KPIs) relevant for maintenance planning and user requirements to improve the usability of CMMS.
Highly Efficient and Mild Gold (I) Catalyzed Synthesis of 3,8-Diarylidene-2,7-dioxaspiro[4.4]nonane-1,6-diones
Authors: Iazzetti Antonia , Allevi Dario , Calcaterra Andrea , Fabrizi Giancarlo , Goggiamani Antonella , Mazzoccanti Giulia , Sferrazza Alessio , Verdiglione Rosanna , Vergine Valeria
Published: January 2023

The gold-catalyzed cyclization of 2,2-bis(3-arylprop-2-yn1-yl)malonic acid has been proposed as an efficient approach to substituted 3,8-dibenzyl-2,7-dioxaspiro[4.4]nonane-1,6-diones. The reaction proceeds smoothly in mild reaction conditions to give the desired products in quantitative yields in the presence of variously substituted starting materials. In addition, the synthesis of γ-arylidene spirobislactone bearing different substituents on the two aromatic rings has been achieved. This kind of compound could be of great interest in pharmaceutical science given the widespread presence of this scaffold in bioactive natural and synthetic products.
Triterpenic Acid Amides as Potential Inhibitors of the SARS-CoV-2 Main Protease
Authors: Baev Dmitry S. , Blokhin Mikhail E. , Chirkova Varvara Yu. , Belenkaya Svetlana V. , Luzina Olga A. , Yarovaya Olga I. , Salakhutdinov Nariman F. , Shcherbakov Dmitry N.
Published: January 2023

Although the incidence and mortality of SARS-CoV-2 infection has been declining during the pandemic, the problem related to designing novel antiviral drugs that could effectively resist viruses in the future remains relevant. As part of our continued search for chemical compounds that are capable of exerting an antiviral effect against the SARS-CoV-2 virus, we studied the ability of triterpenic acid amides to inhibit the SARS-CoV-2 main protease. Molecular modeling suggested that the compounds are able to bind to the active site of the main protease via non-covalent interactions. The FRET-based enzyme assay was used to reveal that compounds 1e and 1b can inhibit the SARS-CoV-2 main protease at micromolar concentrations.
The Fabrication of High-Hardness and Transparent PMMA-Based Composites by an Interface Engineering Strategy
Authors: Cao Bo , Wu Peng , Zhang Wenxiang , Liu Shumei , Zhao Jianqing
Published: January 2023

The high-hardness and transparent PMMA-based composites play a significant role in modern optical devices. However, a well-known paradox is that conventional PMMA-based composites with high loadings of nanoparticles usually possess high surface hardness at the cost of poor transparency and toughness due to the aggregation of nanoparticles. In this work, ideal optical materials (SiO2/PMMA composites) with high transparency and high surface hardness are successfully fabricated through the introduction of the flow modifier Si-DPF by conventional melt blending. Si-DPF with low surface energy and high transparency, which is located at the SiO2/PMMA interface, and nano-SiO2 particles are homogeneously dispersed in the PMMA matrix. As an example, the sample SiO2/PMMA/Si-DPF (30/65/5) shows outstanding transparency (>87.2% transmittance), high surface hardness (462.2 MPa), and notched impact strength (1.18 kJ/m2). Moreover, SiO2/PMMA/Si-DPF (30/65/5) also presents a low torque value of composite melt (21.7 N⋅m). This work paves a new possibility for the industrial preparation of polymer-based composites with excellent transparency, surface hardness, processability, and toughness.
UPLC-MS-ESI-QTOF Analysis and Antifungal Activity of Aqueous Extracts of Spondias tuberosa
Authors: Santos Antonia Thassya Lucas dos , Carneiro Joara Nályda Pereira , da Cruz Rafael Pereira , Sales Débora Lima , Andrade-Pinheiro Jacqueline Cosmo , de Freitas Maria Audilene , Kerntopf Marta Regina , Delmondes Gyllyandeson de Araújo , Ribeiro Paulo Riceli Vasconcelos , de Brito Edy Sousa , Batista Francisco Lucas Alves , Magalhães Francisco Ernani Alves , Pita Neto Ivo C. , Morais-Braga Maria Flaviana Bezerra , Kowalski Radosław , Kowalska Grazyna , Szopa Aleksandra , Baj Tomasz , Coutinho Henrique Douglas Melo
Published: January 2023

This study aimed to identify the chemical composition of the Spondias tuberosa aqueous leaf and root extracts (EALST and EARST) and to evaluate their effect, comparatively, against opportunistic pathogenic fungi. Ultra-Performance Liquid Chromatography Coupled to a Quadrupole/Time of Flight System (UPLC-MS-ESI-QTOF) was employed for chemical analysis. Candida albicans and C. tropicalis standard strains and clinical isolates were used (CA INCQS 40006, CT INCQS 40042, CA URM 5974, and CT URM 4262). The 50% Inhibitory Concentration for the fungal population (IC50) was determined for both the intrinsic action of the extracts and the extract/fluconazole (FCZ) associations. The determination of the Minimum Fungicidal Concentration (MFC) and the verification of effects over fungal morphological transitions were performed by subculture in Petri dishes and humid chambers, respectively, both based on micro-dilution. UPLC-MS-ESI-QTOF analysis revealed the presence of phenolic and flavonoid compounds. The association of the extracts with fluconazole, resulted in IC50 values from 2.62 µg/mL to 308.96 µg/mL. The MFC of the extracts was ≥16,384 µg/mL for all tested strains, while fluconazole obtained an MFC of 8192 µg/mL against C. albicans strains. A reduction in MFC against CA URM 5974 (EALST: 2048 µg/mL and EARST: 1024 µg/mL) occurred in the extract/fluconazole association.
Effect of Acidic Electrolysed Water and Pulsed Light Technology on the Sensory, Morphology and Bioactive Compounds of Pennywort (Centella asiatica L.) Leaves
Authors: Rosli Siti-Zaharah , Mohd Adzahan Noranizan , Karim Roselina , Mahmud Ab Rashid Nor-Khaizura
Published: January 2023

Pennywort (Centella asiatica) is a herbaceous vegetable that is usually served in the form of fresh-cut vegetables and consumed raw. Fresh-cut vegetables are in high demand as they offer convenience, have fresh-like quality and are potentially great for therapeutic applications. However, it could be the cause of foodborne outbreaks. Pulsed light is known as a decontamination method for minimally processed products. The aim of this study was to determine the influence of pulsed light in combination with acidic electrolysed water on the sensory, morphological changes and bioactive components in the leaves of pennywort during storage. A combination of soaking with acidic electrolysed water (AEW) at pH 2.5 and pulsed light (PL) treatment (1.5 J/cm2) was tested on the leaves of pennywort. After treatment, these leaves were refrigerated (4 ± 1 °C) for two weeks and evaluated on the basis of sensory acceptance, the visual appearance of the epidermal cell and bioactive compounds. In terms of sensorial properties, samples treated with the combined treatment were preferred over untreated samples. The combination of AEW and PL 1.5 J/cm2 was the most preferred in terms of purchasing and consumption criteria. Observations of the epidermal cells illustrated that PL treatment kept the cell structure intact. The bioactive phytocompounds found in the leaves of pennywort are mainly from the triterpene glycosides (asiaticoside, madecassoside, asiatic acid and madecassic acid) and are efficiently preserved by the combined treatment applied. In conclusion, the combination of acidic electrolysed water and pulsed light treatment is beneficial in retaining the sensory quality and bioactive compounds in the leaves of Pennywort during storage at 4 ± 1 °C.
Synthesis of Some Mono- and Disaccharide-Grafting Phthalazine Derivatives and Some New Se-Nucleoside Analogues: Antibacterial Properties, Quantum Chemical Calculations, and Cytotoxicity
Authors: El-Shamy I. E. , Hleli E. , Alsheikh A. A. , Yawer M. A. , El-Hashash M. A. , Dybal J. , Abdel-Mohsen A. M.
Published: January 2023

A highly efficient and versatile synthetic approach for the synthesis of 4-(pyren-1-ylmethyl)-1-(d-glycosyloxy) phthalazine nucleosides 11a,b, 13, β-S-nucleosides 16, 18, 20, and acyclo C-nucleosides 23a,b, 24, 25 and 27a–f was described and fully characterized. Furthermore, a series of desired new nucleoside analogues containing Se of 4-(pyren-1-ylmethyl) phthalazine-1(2H)-selenone 28–33 were synthesized. The structures of all reported compounds were confirmed by IR, 1H-NMR, 13C-NMR, MS and elemental analysis. All compounds have been screened for their antibacterial and antifungal activities. Maximum activity was shown by 20 and 33a comparable to the standard drugs with lower toxicity. The cytotoxicity of the selected compound was measured and evaluated. The energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital was calculated using theoretical computations to reflect the chemical reactivity and kinetic stability of the synthesized compounds. Using density functional theory (DFT), electronic parameters such as the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) and the molecular electrostatic potential (MEPS) were calculated. On the basis of different studied structures, these properties were computed in order to elucidate the chemical reactivity and the kinetic stability. Obviously, the band gap energy (Eg) of structures studied reveals that the lowest band gap obtained for the structure 16-a indicates that it has the highest chemical reactivity and lowest kinetic stability.
3D Conformational Generative Models for Biological Structures Using Graph Information-Embedded Relative Coordinates
Authors: Xu Mingyuan , Huang Weifeng , Xu Min , Lei Jinping , Chen Hongming
Published: January 2023

Developing molecular generative models for directly generating 3D conformation has recently become a hot research area. Here, an autoencoder based generative model was proposed for molecular conformation generation. A unique feature of our method is that the graph information embedded relative coordinate (GIE-RC), satisfying translation and rotation invariance, was proposed as a novel way for encoding molecular three-dimensional structure. Compared with commonly used Cartesian coordinate and internal coordinate, GIE-RC is less sensitive on errors when decoding latent variables to 3D coordinates. By using this method, a complex 3D generation task can be turned into a graph node feature generation problem. Examples were shown that the GIE-RC based autoencoder model can be used for both ligand and peptide conformation generation. Additionally, this model was used as an efficient conformation sampling method to augment conformation data needed in the construction of neural network-based force field.
Prediction and Construction of Energetic Materials Based on Machine Learning Methods
Authors: Zang Xiaowei , Zhou Xiang , Bian Haitao , Jin Weiping , Pan Xuhai , Jiang Juncheng , Koroleva M. Yu. , Shen Ruiqi
Published: January 2023

Energetic materials (EMs) are the core materials of weapons and equipment. Achieving precise molecular design and efficient green synthesis of EMs has long been one of the primary concerns of researchers around the world. Traditionally, advanced materials were discovered through a trial-and-error processes, which required long research and development (R&D) cycles and high costs. In recent years, the machine learning (ML) method has matured into a tool that compliments and aids experimental studies for predicting and designing advanced EMs. This paper reviews the critical process of ML methods to discover and predict EMs, including data preparation, feature extraction, model construction, and model performance evaluation. The main ideas and basic steps of applying ML methods are analyzed and outlined. The state-of-the-art research about ML applications in property prediction and inverse material design of EMs is further summarized. Finally, the existing challenges and the strategies for coping with challenges in the further applications of the ML methods are proposed.
Experiences and Perspectives of GC-MS Application for the Search of Low Molecular Weight Discriminants of Schizophrenia
Authors: Porozova Natalia , Danilova Elena , Senshinov Igor , Tsakalof Andreas , Nosyrev Alexander
Published: January 2023

Schizophrenia is one of the most severe chronic mental disorders that is currently diagnosed and categorized through subjective clinical assessment of complex symptoms. At present, there is a recognized need for an objective, unbiased clinical test for schizophrenia diagnosis at an early stage and categorization of the disease. This can be achieved by assaying low-molecular-weight biomarkers of the disease. Here we give an overview of previously conducted research on the discovery of biomarkers of schizophrenia and focus on the studies implemented with the use of GC-MS and the least invasiveness of biological samples acquisition. The presented data demonstrate that GC-MS is a powerful instrumental platform for investigating dysregulated biochemical pathways implicated in schizophrenia pathogenesis. With this platform, different research groups suggested a number of low molecular weight biomarkers of schizophrenia. However, we recognize an inconsistency between the biomarkers or biomarkers patterns revealed by different groups even in the same matrix. Moreover, despite the importance of the problem, the number of relevant studies is limited. The intensification of the research, as well as the harmonization of the analytical procedures to overcome the observed inconsistencies, can be indicated as future directions in the schizophrenia bio-markers quest.
The First Snake Venom KTS/Disintegrins-Integrin Interactions Using Bioinformatics Approaches
Authors: Khamessi Oussema , Ben Mabrouk Hazem , Kamoun Selim , Hkimi Chaima , Ghedira Kais , Kharrat Riadh
Published: January 2023

Snake venom contains a number of active molecules that have been shown to possess high anti-tumor activities; disintegrins are an excellent example among these. Their ability to interact and bind with integrins suggests that they could be very valuable molecules for the development of new cancer therapeutic approaches. However, in the absence of a clear Lysine-Threonine-Serine (KTS) Disintegrins Integrin interaction model, the exact compound features behind it are still unknown. In this study, we investigated the structural characteristics of three KTS-disintegrins and the interaction mechanisms with the α1β1 integrin receptor using in silico bioinformatics approaches. Normal mode analysis showed that the flexibility of the KTSR motif and the C-terminal region play a key role and influence the KTS-Disintegrin-integrin interaction. Protein-protein docking also suggested that the interaction involving the KTSR motif is highly dependent on the residue following K21, S23 and R24. These findings contribute to a better understanding of the KTS-Disintegrin-Integrin structural differences and their interactions with α1β1 receptors, which could improve the selection process of the best active molecules for antitumor therapies.
A Natural CHI3L1—Targeting Compound, Ebractenoid F, Inhibits Lung Cancer Cell Growth and Migration and Induces Apoptosis by Blocking CHI3L1/AKT Signals
Authors: Hong Da Eun , Yu Ji Eun , Lee Jin Woo , Son Dong Ju , Lee Hee Pom , Kim Yuri , Chang Ju Young , Lee Dong Won , Lee Won Kyu , Yun Jaesuk , Han Sang Bae , Hwang Bang Yeon , Hong Jin Tae
Published: January 2023

Our previous big data analyses reported a strong association between CHI3L1 expression and lung tumor development. In this present study, we investigated whether a CHI3L1-inhibiting natural compound, ebractenoid F, inhibits lung cancer cell growth and migration and induces apoptosis. Ebractenoid F concentration-dependently (0, 17, 35, 70 µM) and significantly inhibited the proliferation and migration of A549 and H460 lung cancer cells and induced apoptosis. In the mechanism study, we found that ebractenoid F bound to CHI3L1 and suppressed CHI3L1-associated AKT signaling. Combined treatment with an AKT inhibitor, LY294002, and ebractenoid F synergistically decreased the expression of CHI3L1. Moreover, the combination treatment further inhibited the growth and migration of lung cancer cells and further induced apoptosis, as well as the expression levels of apoptosis-related proteins. Thus, our data demonstrate that ebractenoid F may serve as a potential anti-lung cancer compound targeting CHI3L1-associated AKT signaling.
Recent Progress in Type I Aggregation-Induced Emission Photosensitizers for Photodynamic Therapy
Authors: Yu Yuewen , Jia Hanyu , Liu Yubo , Zhang Le , Feng Guangxue , Tang Ben Zhong
Published: January 2023

In modern medicine, precision diagnosis and treatment using optical materials, such as fluorescence/photoacoustic imaging-guided photodynamic therapy (PDT), are becoming increasingly popular. Photosensitizers (PSs) are the most important component of PDT. Different from conventional PSs with planar molecular structures, which are susceptible to quenching effects caused by aggregation, the distinct advantages of AIE fluorogens open up new avenues for the development of image-guided PDT with improved treatment accuracy and efficacy in practical applications. It is critical that as much of the energy absorbed by optical materials is dissipated into the pathways required to maximize biomedical applications as possible. Intersystem crossing (ISC) represents a key step during the energy conversion process that determines many fundamental optical properties, such as increasing the efficiency of reactive oxygen species (ROS) production from PSs, thus enhancing PDT efficacy. Although some review articles have summarized the accomplishments of various optical materials in imaging and therapeutics, few of them have focused on how to improve the phototherapeutic applications, especially PDT, by adjusting the ISC process of organic optics materials. In this review, we emphasize the latest advances in the reasonable design of AIE-active PSs with type I photochemical mechanism for anticancer or antibacterial applications based on ISC modulation, as well as discuss the future prospects and challenges of them. In order to maximize the anticancer or antibacterial effects of type I AIE PSs, it is the aim of this review to offer advice for their design with the best energy conversion.
Comparative Study of the Efficiency of Additives in the Extraction of Phycocyanin-C from Arthrospira maxima Using Ultrasonication
Authors: Martínez-Vega Jorge Eugenio , Villafaña-Estarrón Erika , Escalante Froylán M. E.
Published: January 2023

Several phycocyanin extraction methods have been proposed, however, most of them present economical or productive barriers. One of the most promising methods that has been suggested is ultrasonication. We have analyzed here the effect of operational conditions and additives on the extraction and purity of phycocyanin from Arthrospira maxima. We followed three experimental designs to determine the best combination of buffered pH solutions, additives, fresh and lyophilized biomass. We have found that additives such as citric acid and/or disaccharides could be beneficial to the extraction process. We concluded that the biomass–solvent ratio is a determining factor to obtain high extraction and purity ratios with short ultrasonication times.
Inhibition of Cancer Cell Proliferation and Bacterial Growth by Silver(I) Complexes Bearing a CH3-Substituted Thiadiazole-Based Thioamide
Authors: Varna Despoina , Geromichalou Elena , Karlioti Georgia , Papi Rigini , Dalezis Panagiotis , Hatzidimitriou Antonios G. , Psomas George , Choli-Papadopoulou Theodora , Trafalis Dimitrios T. , Angaridis Panagiotis A.
Published: January 2023

Ag(I) coordination compounds have recently attracted much attention as antiproliferative and antibacterial agents against a wide range of cancer cell lines and pathogens. The bioactivity potential of these complexes depends on their structural characteristics and the nature of their ligands. Herein, we present a series of four Ag(I) coordination compounds bearing as ligands the CH3-substituted thiadiazole-based thioamide 5-methyl-1,3,4-thiadiazole-2-thiol (mtdztH) and phosphines, i.e., [AgCl(mtdztH)(PPh3)2] (1), [Ag(mtdzt)(PPh3)3] (2), [AgCl(mtdztH)(xantphos)] (3), and [AgmtdztH)(dppe)(NO3)]n (4), where xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene and dppe = 1,2-bis(diphenylphosphino)ethane, and the assessment of their in vitro antibacterial and anti-cancer efficiency. Among them, diphosphine-containing compounds 3 and 4 were found to exhibit broad-spectrum antibacterial activity characteristics against both Gram-(+) and Gram-(–) bacterial strains, showing high in vitro bioactivity with IC50 values as low as 4.6 μΜ. In vitro cytotoxicity studies against human ovarian, pancreatic, lung, and prostate cancer cell lines revealed the strong cytotoxic potential of 2 and 4, with IC50 values in the range of 3.1–24.0 μΜ, while 3 and 4 maintained the normal fibroblast cells’ viability at relatively higher levels. Assessment of these results, in combination with those obtained for analogous Ag(I) complexes bearing similar heterocyclic thioamides, suggest the pivotal role of the substituent groups of the thioamide heterocyclic ring in the antibacterial and anti-cancer efficacy of the respective Ag(I) complexes. Compounds 1–4 exhibited moderate in vitro antioxidant capacity for free radicals scavenging, as well as reasonably strong ability to interact with calf-thymus DNA, suggesting the likely implication of these properties in their bioactivity mechanisms. Complementary insights into the possible mechanism of their anti-cancer activity were provided by molecular docking calculations, exploring their ability to bind to the overexpressed fibroblast growth factor receptor 1 (FGFR1), affecting cancer cells’ functionalities.