bluuebunny/crossref_metadata_2025 huggingface dataset:
The Incidence and Characteristics of Oral Candidiasis in Patients Hospitalized for SARS-CoV-2 Infection During the Circulation of Alpha, Beta, and Delta Variants
Authors: Kouris Elena Camelia , Mirea Sînziana Irina , Luminos Monica Luminița , Miron Victor Daniel
Published: October 2024

Background: Oral candidiasis has been documented in patients with SARS-CoV-2 infection, with varying prevalence rates across geographic regions and patient demographics. This study aimed to ascertain the incidence, characteristics, and risk factors associated with the development of oral candidiasis in patients hospitalized for SARS-CoV-2 infection in a tertiary infectious diseases hospital in Romania. Methods: A retrospective analysis was conducted on adult patients hospitalized between March 2020 and December 2022 with moderate or severe forms of SARS-CoV-2 infection, for whom a culture of lingual scrapings for Candida spp. was performed. Results: A total of 294 patients were deemed eligible for inclusion in the analysis, with an incidence rate of oral candidiasis of 17.0%. The incidence of oral candidiasis was 4.2 times higher in patients with severe forms of SARS-CoV-2 infection compared to those with moderate forms. Patients with a diagnosis of COVID-19 and oral candidiasis were more likely to receive antibiotics (98.0% vs. 86.1%, p = 0.017) and corticosteroids (100% vs. 83.6%, p = 0.003) than those without oral candidiasis. These findings were associated with a 19% higher relative risk of developing oral candidiasis for patients who received corticosteroid therapy compared to those who did not, and a 13% higher relative risk for those who were administered antibiotics compared to those who were not. The presence of respiratory insufficiency increased the odds of oral candidiasis association 4.7-fold (88.0% vs. 61.1%, p < 0.001). Conclusions: Although the data have been analyzed retrospectively, we have shown that individuals with severe forms of COVID-19 exhibited an elevated risk of developing oral candidiasis. The administration of antibiotics and corticosteroids was identified as a positive predictor for the development of oral candidiasis. The data presented here suggest that a key aspect of the therapeutic management of patients with SARS-CoV-2 infection should include the implementation of preventive measures to minimize the risk of secondary fungal infections.
FgUbiH Is Essential for Vegetative Development, Energy Metabolism, and Antioxidant Activity in Fusarium graminearum
Authors: Ge Jinwen , Zhai Huanchen , Tang Lei , Zhang Shuaibing , Lv Yangyong , Ma Pingan , Wei Shan , Zhou Yu , Wu Xiaofu , Lei Yang , Zhao Fengguang , Hu Yuansen
Published: October 2024

Fusarium head blight in wheat is mainly caused by Fusarium graminearum and results in significant economic losses. Coenzyme Q (CoQ) is ubiquitously produced across organisms and functions as a hydrogen carrier in energy metabolism. While UbiH in Escherichia coli serves as a hydroxylase in CoQ biosynthesis, its role in phytopathogenic fungi is not well understood. This study explored the role of the hydroxylase FgUbiH in F. graminearum. Using a FgUbiH deletion mutant, we observed reduced hyphal growth, conidial production, germination, toxin synthesis, and pathogenicity compared to the wild-type. A transcriptome analysis indicated FgUbiH’s involvement in regulating carbohydrate and amino acid metabolism. Deletion of FgUbiH impaired mitochondrial function, reducing adenosine triphosphate synthesis and increasing reactive oxygen species. Additionally, genes related to terpene skeleton synthesis and aldehyde dehydrogenase were downregulated. Our results underscore the importance of FgUbiH in F. graminearum’s growth, toxin production, and energy metabolism, aiding in the development of strategies for disease management.
Role of the SaeRS Two-Component Regulatory System in Group B Streptococcus Biofilm Formation on Human Fibrinogen
Authors: Coppolino Francesco , Berbiglia Alessia , Lentini Germana , Famà Agata , Pietrocola Giampiero , Teti Giuseppe , Beninati Concetta , De Gaetano Giuseppe Valerio
Published: October 2024

Streptococcus agalactiae, also known as Group B Streptococcus or GBS, is a commensal colonizer of human vaginal and gastrointestinal tracts that can also be a deadly pathogen for newborns, pregnant women, and the elderly. The SaeRS two-component regulatory system (TCS) positively regulates the expression of two GBS adhesins genes, but its role in the formation of biofilm, an important step in pathogenesis, has not been investigated. In the present study, we set up a novel model of GBS biofilm formation using surfaces coated with human fibrinogen (hFg). Biofilm mass and structure were analyzed by crystal violet staining and three-dimensional fluorescence microscopy, respectively. GBS growth on hFg resulted in the formation of a mature and abundant biofilm composed of bacterial cells and an extracellular matrix containing polysaccharides, proteins, and extracellular DNA (eDNA). Enzymatic and genetic analysis showed that GBS biofilm formation on hFg is dependent on proteins and eDNA in the extracellular matrix and on the presence of covalently linked cell wall proteins on the bacterial surface but not on the type-specific capsular polysaccharide. In the absence of the SaeR regulator of the SaeRS TCS, there was a significant reduction in biomass formation, with reduced numbers of bacterial cells, reduced eDNA content, and disruption of the biofilm architecture. Overall, our data suggest that GBS binding to hFg contributes to biofilm formation and that the SaeRS TCS plays an important role in this process.
Antibiotic Susceptibility-Guided Concomitant Therapy Regimen with Vonoprazan, High-Dose Amoxicillin, Clarithromycin, and Metronidazole for Helicobacter pylori Eradication as Fourth-Line Regimen: An Interventional Study
Authors: Sue Soichiro , Sato Takeshi , Matsubayashi Mao , Kaneko Hiroaki , Irie Kuniyasu , Maeda Shin
Published: October 2024

This is the first registered intervention study for vonoprazan, high-dose amoxicillin, clarithromycin, and metronidazole 14-day concomitant therapy based on a susceptibility test of Helicobacter pylori. We conducted this study as a fourth-line rescue regimen in Japan. Methods: Twenty patients who underwent three rounds of eradication therapies (first- or second-line 7-day triple therapy consisting of amoxicillin and clarithromycin, or metronidazole- and sitafloxacin-based third-line therapy) and had failed eradication based on a urea breath test or fecal antigen test were recruited. All patients underwent endoscopic examination and culture tests before starting eradication therapy. The intervention was concomitant therapy consisting of vonoprazan 20 mg bid, amoxicillin 500 mg qid, clarithromycin 400 mg bid, and metronidazole 250 mg bid for 14 days, which were modified based on the susceptibility test, and the resistant drugs were removed from the regimen. Patients with negative culture results were treated with quadruple therapy. The primary outcome was the eradication rate (UMIN000025765, jRCTs 031180208). Results: The eradication rate of susceptibility-testing-based fourth-line eradication therapy was 63.2% (95%CI: 38.4–83.7%) in intent-to-treat analysis and 70.6% (95%CI: 44.0–89.7%) in per-protocol analysis. Thirteen patients received quadruple therapy, with eradication rates of 61.5% and 75.0%, respectively. No serious adverse events were reported. Conclusions: This vonoprazan-based concomitant therapy modified by the susceptibility test is a potential option as fourth-line eradication after first-line clarithromycin-based 7-day triple, second-line metronidazole-based 7-day triple, and third-line sitafloxacin-based 7-day triple therapy failure.
Baggio–Yoshinari Syndrome: A Report of Five Cases
Authors: Bonoldi Virginia Lucia Nazario , Yoshinari Natalino Hajime , Trevisan Giusto , Bonin Serena
Published: October 2024

Compared to classic Lyme disease (LD), Baggio–Yoshinari syndrome (BYS) has the following distinctive characteristics: it is transmitted in the Amazon area and Northeast, Central-West, Southeast, and South regions of Brazil by hard ticks, notably Amblyomma cajannense or Rhipicefalus sp. The absence of Ixodes sp. ticks in areas at risk of BYS in Brazil is probably the main reason for the disease’s differences from LD in the United States, Europe, and Asia. Biodiversity and climate probably favor the formation of atypical pleomorphic Borrelias, which have not yet been cultivated or isolated. Clinically, the first manifestation of BYS is the erythema migrans as in the classic forms of Lyme disease, but BYS is distinguished from LD by its prolonged clinical evolution, with a high frequency of relapses and the appearance of autoimmune manifestations. Prevalent symptoms are headache and erythema nodosum. Five clinical cases of BYS in patients who contracted the disease in the Brazilian Amazon rainforest are described here. This syndrome should be considered among differential diagnoses in patients bitten by ticks in Brazil who present with erythema migrans and/or headache. It is important to pursue an early diagnosis because symptoms respond well to antibiotics in the early stages; if treatment is started late, a chronic course with articular and neurological sequelae can be detected.
The Consumption of Lacticaseibacillus rhamnosus HDB1258 Changes Human Gut Microbiota and Induces Immune Enhancement Through NK Cell Activation
Authors: Lee Jin-Joo , Kim Kyung-Min , Kim Hyeon-Jeong , Sohn Johann , Song Ji-Won , Koo Hye-Yeon , Lee Seunghun
Published: October 2024

The gut microbiota can play an important role in enhancing the host’s complex immune system. In this regard, many studies indicate that probiotics consumption has a beneficial impact on alterations in the composition of the gut microbiota. Our previous study demonstrated that the oral administration of Lacticaseibacillus rhamnosus HDB1258 (HDB1258) enhances immune cell activity and alters the composition of gut microbiota in C57BL/6 mice, thereby showing its potential as a novel immunostimulatory ingredient. Therefore, this clinical trial assessed the effects of HDB1258 on human natural killer (NK) cell activity and changes in gut microbiota. It also investigated the correlation between gut microbiota and NK cell activity following HDB1258 supplementation. Participants (n = 71) were randomized into placebo and HDB1258 groups, and NK cell activity and gut microbiota were investigated at baseline (week 0) and endline (week 8). The present study showed that HDB1258 significantly increased NK cell activity and resulted in positive regulatory effects on the gut microbial balance in subjects compared to the placebo group. HDB1258 affected the gut microbial balance by inducing the growth of beneficial bacteria such as Lactococcus and Sutterella. Especially, the changes in Escherichia–Shigella composition were negatively correlated with the changes in NK cell activity after HDB1258 consumption. There was also a positive correlation between the NK cell activity in the HDB1258 group and the composition of Prevotella 9 and Adlercreutzia. These findings suggest that HDB1258 may improve the host’s intestinal environment by regulating gut bacteria related to immune response and promote NK cell activation. This study was registered at clinical research information service (CRIS: KCT0008204).
A New Real-Time PCR Test (Flora Select™) and Nugent Score for the Diagnosis of Bacterial Vaginosis During Pregnancy
Authors: Yamada Hideto , Shimada Shigeki , Ota Hajime , Kobayashi Yuta , Fukushi Yoshiyuki , Wada Shinichiro , Kataoka Soromon
Published: October 2024

This prospective cohort study aimed to evaluate the performance of Flora select™ (FS), a newly developed real-time PCR test, for the assessment of the vaginal microbiome during early pregnancy. Five hundred and fifty-six pregnant women underwent examinations of FS, Nugent score—a Gram-staining scoring system for the diagnosis of bacterial vaginosis (BV)—and conventional bacterial culture between 8 weeks and 12 gestational weeks. Nugent scores of 0–3, 4–6, and ≥7 were found in 469 (84.2%), 41 (7.4%), and 47 (8.5%) of the women, respectively. Relative dominance rates of Lactobacillus species of high (≥80% medium (50%≤, <80%), and low (0.1≤, <50%), and no detection (<0.1%) were 63.0%, 8.8%, 17.1%, and 11.2%, respectively. Gardnerella, Prevotella, Atopobium, Streptococcus, Ureaplasma, and Mycoplasma species were detected in 23.9%, 17.6%, 17.1%, 7.0%, 23.0%, and 4.9% of the women, respectively. Gardnerella species were detected in all women with Nugent scores ≥7 and Ureaplasma were detected in 40.4% of them. BV-associated bacterial species were also detected in 70.7% of women with Nugent scores of 4–6. Gardnerella, Prevotella, Atopobium, Streptococcus, Ureaplasma, and Mycoplasma species were highly prevalent in women with Nugent scores ≥4 or Lactobacillus species <50%. FS detected Gardnerella, Prevotella, and Atopobium species more effectively than conventional bacterial culture. FS could determine relative dominance rates of Lactobacillus species in the vaginal microbiome, and simultaneously detect four kinds of BV-associated bacteria, Ureaplasma and Mycoplasma species. Therefore, FS may be clinically useful for the screening of the vaginal microbiome during pregnancy to prevent preterm birth and for the assessment of the vaginal microbiome after BV treatments.
‘Rhythmite’, Ca29(SiO4)8Cl26, an Anthropogenic Phase from the Chelyabinsk Coal Basin (Ural, Russia) with a Complex Modular Structure Related to α-Ca3SiO4Cl2 (‘Albovite’): Crystal Structure, Raman Spectra, and Thermal Expansion
Authors: Avdontceva Margarita S. , Zolotarev Andrey A. , Brazhnikova Anastasia S. , Bocharov Vladimir N. , Vlasenko Natalia S. , Rassomakhin Mikhail A. , Krivovichev Sergey V.
Published: October 2024

‘Rhythmite’, Ca29(SiO4)8Cl26, an anthropogenic calcium chloride silicate from the Chelyabinsk coal basin (South Ural, Russia), was investigated using chemical microprobe analysis, in situ single-crystal X-ray diffraction analysis (27–727 °C), and Raman spectroscopy. ‘Rhythmite’ is orthorhombic, Pnma: a = 17.0749(6), b = 15.1029(5), c = 13.2907(4) Å, and V = 3427.42(18) Å3 (R1 = 0.045). The crystal structure of ‘rhythmite’ consists of a porous framework formed by Ca-O bonds and SiO4 tetrahedra with additional Ca2+ cations and Cl− anions in the structure interstices. The framework is built up from multinuclear [Ca15(SiO4)4]14+ fundamental building blocks (FBBs) cut from the crystal structure of α-Ca3SiO4Cl2 (‘albovite’). The FBBs are linked by sharing common Ca atoms to form a network with an overall pcu topology. The empirical chemical formula was calculated as Ca29.02(Si7.89Al0.05P0.05)Ʃ7.99O32Cl26 (on the basis of Cl + O = 58). ‘Rhythmite’ is stable up to 627 °C and expands slightly anisotropically (αmax/αmin = 1.40) in the ab and bc planes and almost isotropically in the ac plane (α33/α11 = 1.02) with the following thermal expansion coefficients (×106 °C−1): α11 = 14.6(1), α22 = 20.5(4), α33 = 15.0(3), and αV = 50.1(6) (room temperature). During expansion, the silicate tetrahedra remain relatively rigid with average bond length changes of less than 0.5%. A structural complexity analysis indicates that ‘rhythmite’ is complex, with IG,total = 920.313 (bits/u.c.), which significantly exceeds the average value of structural complexity for silicates and is caused by the modular framework construction and the presence of a large number of independent positions in the crystal structure.
Accumulated Copper Tailing Solid Wastes with Specific Compositions Encourage Advances in Microbial Leaching
Authors: Zhang Juan , Liu Xiaojun , Du Xinyue , Wang Xin , Zeng Yifan , Fan Shukai
Published: October 2024

Against the backdrop of the increasing copper demand in a low-carbon economy, this work statistically forecasted the distribution of China’s copper tailings for the first time, and then characterized them as finely crushed and low-grade mining solid wastes containing copper mainly in the form of chalcopyrite, bornite, covelline, enargite and chalcocite based on available research data. China is the globally leading refined copper producer and consumer, where the typical commercial-scale bioleaching of copper tailings is conducted in the Dexing, Zijinshan and Jinchuan mining regions. And these leaching processes were compared in this study. Widely used chemolithoautotrophic and mesophilic bacteria are Acidithiobacillus, Leptospirillum, Acidiphilium, Alicyclobacillus and Thiobacillus with varied metal resistance. They can be used to treat copper sulfide tailings such as pyrite, chalcopyrite, enargite, chalcocite, bornite and covellite under sufficient dissolved oxygen from 1.5 to 4.1 mg/L and pH values ranging from 0.5 to 7.2. Moderate thermophiles (Acidithiobacillus caldus, Acidimicrobium, Acidiplasma, Ferroplasma and Sulfobacillus) and extreme thermophilic archaea (Acidianus, Metallosphaera, Sulfurococcus and Sulfolobus) are dominant in leaching systems with operating temperatures higher than 40 °C. However, these species are vulnerable to high pulp density and heavy metals. Heterotrophic Acidiphilium multivorum, Ferrimicrobium, Thermoplasma and fungi use organic carbon as energy to treat copper oxides (malachite, chrysocolla and azurite) and weathered sulfides (bornite, chalcocite, digenite and covellite) under a wide pH range and high pulp density. We also compared autotrophs in a planktonic state or biofilm to treat different metal sulfides using various sulfur-cycling enzymes involved in the polysulfide or thiosulfate pathways against fungi that produce various organic acids to chelate copper from oxides. Finally, we recommended a bioinformatic analysis of functional genes involved in Fe/S oxidization and C/N metabolism, as well as advanced representation that can create new possibilities for the development of high-efficiency leaching microorganisms and insight into the mechanisms of bioleaching desired metals from complex and low-grade copper tailings.
The Crystal Chemistry of Boussingaultite, (NH4)2Mg(SO4)2·6H2O, and Its Derivatives in a Wide Temperature Range
Authors: Zhitova Elena S. , Sheveleva Rezeda M. , Zolotarev Andrey A. , Shendrik Roman Yu. , Pankrushina Elizaveta A. , Turovsky Konstantin A. , Avdontceva Margarita S. , Krzhizhanovskaya Maria G. , Vlasenko Natalia S. , Zolotarev Anatoly A. , Rassomakhin Mikhail A. , Krivovichev Sergey V.
Published: October 2024

The crystal structure, thermal behavior, and vibrational spectra of the anthropogenic analogue of boussingaultite, (NH4)2Mg(SO4)2·6H2O, and its dehydrated counterpart efremovite, (NH4)2Mg2(SO4)3, were studied in detail. The sample from the Chelyabinsk burning coal dumps has the composition of (NH4)1.92(Mg1.02Mn0.01Fe0.01)∑1.04(SO4)2·6H2O and crystallizes in the space group P21/a, with a = 9.3183(4), b = 12.6070(4), c = 6.2054(3) Å, β = 107.115(5)°, V = 696.70(5) Å3 (at 20 °C), Z = 2. The thermal evolution steps are as follows: boussingaultite (NH4)2Mg(SO4)2·6H2O (25–90 °C) → X-ray amorphous phase (100–150 °C) → efremovite (NH4)2Mg2(SO4)3 (160–340 °C) → MgSO4 Cmcm + Pbnm (340–580 °C) → MgSO4 Pbnm (580–700 °C). Thermal expansion is anisotropic, with the coefficients (×106 °C−1) α11 = 52(2), α22 = 68(2), α33 = –89(3), and αv = 31(3) at T = –123 °C; and α11 = 53(2), α22 = 67(2), α33 = 15(1), and αv = 136(3) at T = 60 °C. The maximal thermal expansion is along the b-axis and is due to straightening of corrugated pseudolayers (within the ab plane) of Mg(H2O)6 octahedra and SO4 tetrahedra with NH4 groups in the interlayer space. Vibrational spectroscopy outlines the general trend of dehydration and deammonization as the difference in the temperature intervals of these transformation steps allows separation of O–H and N–H vibrations in the process of dehydration by infrared and Raman spectroscopy. The intermediate partially dehydrated modification of boussingaultite was detected by in situ Raman spectroscopy at 110 °C that may correspond to ammonium leonite.
Modeling and Hybrid Inversion of Mineral Deposits Using the Dipping Dike Model with Finite Depth Extent
Authors: Oliveira Saulo Pomponet , Azevedo Juarez dos Santos , Batista Joelson da Conceição , Novais Diego Menezes
Published: October 2024

The dipping dike model has shown to be a useful approximation for mineral deposits. To make this model more realistic, we include the thickness, which yields the depth to the bottom, as an additional parameter. The magnetic anomaly is obtained by combining the anomalies of two infinite dikes, so that the resulting expression is simpler than the classical prismatic models with polygonal cross section. We employ a Metropolis-Hasting (MH) algorithm coupled with the Levenberg-Marquardt (LM) method to invert magnetic profiles assuming a model of multiple dike-like sources. We use a few iterations of the LM method to improve the candidate solutions at the end of each random walk generated by MH. The following parameters are obtained: depth to the top, thickness, half-width, horizontal location of the top center, geological dip, in addition to two effective parameters that depend on the intensity of magnetization and the directions of the induced and remanent fields. For synthetic anomalies, both noise-free and noisy magnetic data are considered, with examples presented for each scenario. These examples highlight the discrepancy between models with finite and infinite sources. They also illustrate the higher accuracy of the hybrid MH-LM method over the pure MH approach. Moreover, two field examples related to mineral exploration have been considered: the Pima copper mine, United States, where the relative differences between the parameters obtained by our algorithm and those known from drilling are not higher than 10%, and a magnetic profile over iron ore deposits located in Laje, northeast Brazil, where the inverted parameters were useful for detailing previous studies.
Age, Mineral Chemistry, and Geochemistry of Metamorphic Basement Rocks from the Southern Yap Arc, Western Pacific
Authors: Yan Shishuai , Yan Quanshu , Yuan Long , Ye Xiantao
Published: October 2024

Studying the basement characteristics and tectonic evolution of the proto-Yap Izu–Bonin–Mariana arc system can provide essential clues for understanding the subduction process in the Western Pacific Ocean. The Yap arc is a part of the Izu–Bonin–Mariana (IBM) arc, but the origin and formation time of the metamorphic basement rocks of the Yap arc still need to be determined. In this paper, we present the first systematic and detailed chronological, mineralogical, whole-rock major element and trace element research on metamorphic basement rocks from four stations in the Southern Yap arc and discuss the origin of the metamorphic basement rocks in the Southern Yap arc. The results show that the single mineral U-Pb ages of titanites and 40Ar/39Ar ages of amphiboles in the Southern Yap arc are 19.3 and 19.4 Ma, respectively, which are consistent within the error ranges, and these ages represent the metamorphic age of the basement rocks. The amphibolite is mainly produced via the metamorphism of back-arc basin basalt (BABB) and forearc basalt (FAB). The temperature and pressure conditions of this metamorphism are 446.5–641.6 °C and 0.24–0.73 GPa, the facies series of which is the medium P/T series. This study provides important data for understanding the Yap subduction system and the early evolution of the proto-IBM Arc.
High-Efficiency and Fast Hydrogen Production from Sodium Borohydride: The Role of Adipic Acid in Hydrolysis, Methanolysis and Ethanolysis Reactions
Authors: Gurdal Savas
Published: October 2024

In this study, hydrogen production through the hydrolysis, ethanolysis, and methanolysis reactions of NaBH4 using adipic acid as a catalyst was investigated for the first time. Adipic acid solutions were prepared with methanol and ethanol at concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 M. In these reactions, NaBH4-MR (methanolysis) and NaBH4-ER (ethanolysis) reactions were carried out at 30, 40, and 50 °C with NaBH4 concentrations of 1.25%, 2.5%, and 5%. Hydrolysis reactions (NaBH4-HR) were conducted at 0.1 M under the same conditions. In the ethanolysis and methanolysis reactions at 30 °C, total hydrogen conversion was achieved at 0.3 M, 0.4 M, and 0.5 M. However, in the hydrolysis reactions, total hydrogen production was only obtained at 50 °C. It was observed that in the NaBH4-MR and NaBH4-ER reactions, total hydrogen conversion could be achieved within 4–5 s. The utilization of adipic acid as a catalyst for hydrogen production from NaBH4 through ethanolysis and methanolysis reactions is proposed as a highly efficient and fast method, characterized by impressive conversion rates.
Exploration of the Solubility Hyperspace of Selected Active Pharmaceutical Ingredients in Choline- and Betaine-Based Deep Eutectic Solvents: Machine Learning Modeling and Experimental Validation
Authors: Cysewski Piotr , Jeliński Tomasz , Przybyłek Maciej
Published: October 2024

Deep eutectic solvents (DESs) are popular green media used for various industrial, pharmaceutical, and biomedical applications. However, the possible compositions of eutectic systems are so numerous that it is impossible to study all of them experimentally. To remedy this limitation, the solubility landscape of selected active pharmaceutical ingredients (APIs) in choline chloride- and betaine-based deep eutectic solvents was explored using theoretical models based on machine learning. The available solubility data for the selected APIs, comprising a total of 8014 data points, were collected for the available neat solvents, binary solvent mixtures, and DESs. This set was augmented with new measurements for the popular sulfa drugs in dry DESs. The descriptors used in the machine learning protocol were obtained from the σ-profiles of the considered molecules computed within the COSMO-RS framework. A combination of six sets of descriptors and 36 regressors were tested. Taking into account both accuracy and generalization, it was concluded that the best regressor is nuSVR regressor-based predictive models trained using the relative intermolecular interactions and a twelve-step averaged simplification of the relative σ-profiles.
Kinetic and Mechanistic Analysis of Phenol Adsorption on Activated Carbons from Kenaf
Authors: Omenat-Morán Delia , Durán-Valle Carlos J. , Martínez-Cañas Manuel A.
Published: October 2024

Activated carbons were prepared from kenaf (Hibiscus cannabinus L.). Carbonization was carried out at 600 °C for 2 h, and activation was performed using air at 600 °C and using CO2 at 750 °C. The activated carbons obtained were treated with HNO3 and H2SO4. The samples were characterized by their chemical and physical structure. The activated carbons obtained were mainly macroporous, and their structure underwent major changes with the activation method and acid treatment. Activated carbons were alkaline and acid-treated carbons were neutral. They were used for phenol adsorption and a kinetic and mechanistic study of adsorption was carried out. The fit to the pseudo-second order and Elovich models was predominant. The rate-limiting step of the process was determined to be diffusion within the pores, as the experimental data fit the Bangham model. DFT simulation showed that the preferred adsorption position involves π-π stacking and that oxidation enhances this interaction. Furthermore, the simulation showed that the interaction of phenol with oxygenated functional groups depends on the type of functional group.
Utilization of Tea Polyphenols as Color Developers in Reversible Thermochromic Dyes for Thermosensitive Color Change and Enhanced Functionality of Polyester Fabrics
Authors: Zhou Weimian , Yang Qun , Tao Sixuan , Cui Jin , Zhu Jie , Zhou Siyu , Li Ruimiao , Su Juan , Zhang Ning , Xu Lihui , Pan Hong , Wang Jiping
Published: October 2024

Thermochromic textiles possess the capability to indicate ambient temperature through color changes, enabling real-time temperature monitoring and providing temperature warnings for body heat management. In this study, three thermochromic dyes—blue, red, and yellow—were synthesized using crystalline violet lactone (CVL), 6′-(diethylamino)-1′,3′-dimethyl-fluoran (DDF), and 3′,6′-dimethoxyfluoran (DOF) as leuco dyes, respectively, with biomass tea polyphenol serving as the color developer and tetradecanol as the phase change material. The chemical structures of these dyes were characterized using UV spectroscopy, infrared spectroscopy, Raman spectroscopy and 1H NMR. The thermochromic mechanisms were investigated, revealing that the binding bonds between the leuco dyes and the color developer broke and reorganized with temperature changes, imparting reversible thermochromic property. Polyester fabrics were dyed using an impregnation method to produce three reversible thermochromic fabrics in blue, red, and yellow. The structure and properties of these fabrics were analyzed, showing a significant increase in the UPF value from 26.3 to approximately 100, indicating enhanced UV resistance. Water contact angle measurements revealed that the contact angle of undyed polyester fabrics was 139°, while that of dyed polyester fabrics decreased by about 40°, indicating improved hydrophilicity. Additionally, the fabric inductive static tester showed that the static voltage half-life of dyed polyester fabric was less than 1 s, demonstrating a significant antistatic effect. Infrared thermal imaging results indicated that during the warming and cooling process, the thermochromic polyester fabric exhibited specific energy storage and insulation effects at 38 °C, close to the human body temperature. This study presented a novel approach to developing smart color-changing textiles using biomass-derived thermochromic dyes, offering diverse materials for personal thermal management, and intelligent insulation applications.
Recovery of Low-Concentration Tungsten from Acidic Solution Using D318 Macroporous Resin
Authors: Zeng Xiangrong , Zeng Bin , Liang Binjun , Zhang Kuifang , Huang Lijinhong , Liu Xinzhe , Huang Wanfu
Published: October 2024

Tungsten is a crucial strategic metal that plays a significant role in various fields, such as the defense industry, fine chemicals, and the preparation of new materials. During the practice of numerous tungsten smelting processes, a large amount of acidic wastewater containing low concentrations of WO3 is generated. The adsorption method, known for its simplicity, effectiveness, and ease of operation, represents the most promising approach for tungsten recovery and is vital for the sustainable development of the tungsten industry. In this study, D318 macroporous resin was used as an adsorbent to investigate its effectiveness in adsorbing WO3 from acidic solutions. Static adsorption experiments revealed that the adsorption capacity of D318 resin for WO3 was 683 mg·g−1. Kinetic analysis indicated that the controlling step for the adsorption of WO3 from acidic solutions by D318 resin was intraparticle diffusion. Thermodynamic analysis demonstrated that the adsorption process was endothermic and could occur spontaneously. By fitting the isothermal adsorption equation, it was found that the Langmuir model was more suitable for describing the adsorption process of WO3 on D318 resin in acidic solutions. The results of dynamic adsorption experiments showed that under optimized conditions, the dynamic adsorption capacity for WO3 was 529 mg·g−1; when using NaOH as the desorbent for cyclic desorption, the desorption rate for WO3 was 98.21%. XPS and SEM-EDS testing and analysis confirmed that D318 macroporous resin exhibited excellent adsorption performance for tungsten in acidic solutions.
High Fluorescence of Phytochromes Does Not Require Chromophore Protonation
Authors: Katz Sagie , Phan Hoang Trong , Rieder Fabian , Seifert Franziska , Pietzsch Markus , Laufer Jan , Schmitt Franz-Josef , Hildebrandt Peter
Published: October 2024

Fluorescing proteins emitting in the near-infrared region are of high importance in various fields of biomedicine and applied life sciences. Promising candidates are phytochromes that can be engineered to a small size and genetically attached to a target system for in vivo monitoring. Here, we have investigated two of these minimal single-domain phytochromes, miRFP670nano3 and miRFP718nano, aiming at a better understanding of the structural parameters that control the fluorescence properties of the covalently bound biliverdin (BV) chromophore. On the basis of resonance Raman and time-resolved fluorescence spectroscopy, it is shown that in both proteins, BV is deprotonated at one of the inner pyrrole rings (B or C). This protonation pattern, which is unusual for tetrapyrroles in proteins, implies an equilibrium between a B- and C-protonated tautomer. The dynamics of the equilibrium are slow compared to the fluorescence lifetime in miRFP670nano3 but much faster in miRFP718nano, both in the ground and excited states. The different rates of proton exchange are most likely due to the different structural dynamics of the more rigid and more flexible chromophore in miRFP670nano3 and miRFP718nano, respectively. We suggest that these structural properties account for the quite different fluorescent quantum yields of both proteins.
Tuning Barrier Properties of Low-Density Polyethylene:  Impact of Amorphous Region Nanostructure on Gas Transmission Rate
Authors: Safandowska Marta , Makarewicz Cezary , Rozanski Artur
Published: October 2024

This work focused on determining the factors that are of key importance in the oxygen barrier properties of low-density polyethylene (LDPE). It has been shown that, depending on the type and amount of the low-molecular-weight compound (tetracosane, paraffin wax, paraffin oil) introduced into the LDPE matrix, it can contribute to the improvement or deterioration of barrier properties. Tetracosane and paraffin wax incorporated into the LDPE matrix caused a reduction in oxygen permeability parameters compared to neat polyethylene. As their content increased, the barrier properties of the samples towards oxygen also increased. A completely opposite effect was achieved with paraffin oil. The results of comprehensive studies provide evidence that in the case of LDPE blends, two mechanisms are responsible for changing/controlling their transport properties. The first mechanism is associated with changes in the molecular packing in the interlamellar amorphous regions, while the second is related to the crystallinity of the samples. In cases where there are no changes in crystallinity, the density of the amorphous phase becomes the decisive factor in barrier properties, as clearly shown by results assessing chain dynamics.
The Role of Peptides in Combatting HIV Infection: Applications and Insights
Authors: Helmy Naiera M. , Parang Keykavous
Published: October 2024

Peptide-based inhibitors represent a promising approach for the treatment of HIV-1, offering a range of potential advantages, including specificity, low toxicity, and the ability to target various stages of the viral lifecycle. This review outlines the current state of research on peptide-based anti-HIV therapies, highlighting key advancements and identifying future research directions. Over the past few years, there has been significant progress in developing synthetic peptide-based drugs that target various stages of the viral life cycle, including entry and replication. These approaches aim to create effective anti-HIV therapies. Additionally, peptides have proven valuable in the development of anti-HIV vaccines. In the quest for effective HIV vaccines, discovering potent antigens and designing suitable vaccine strategies are crucial for overcoming challenges such as low immunogenicity, safety concerns, and increased viral load. Innovative strategies for vaccine development through peptide research are, therefore, a key focus area for achieving effective HIV prevention. This review aims to explore the strategies for designing peptides with anti-HIV activity and to highlight their role in advancing both therapeutic and preventive measures against HIV.
Heat Transfer in Carbon-Nanotube Dispersions: A Simulation Study of the Role of Nanotube Morphology and Connectivity
Authors: Polydoropoulou Panagiota V. , Burganos Vasilis N.
Published: October 2024

Simulation of the behavior of carbon nanotubes (CNTs) can become a very challenging task considering their complicated shape and large aspect ratio. This study aims to elucidate the role of CNT shape, length, and connectivity during heat transfer in CNT dispersions through a three-dimensional (3D) simulator. Three characteristic shapes for the CNTs are considered, namely, straight, moderately curved, and strongly curved. The results reveal that the commonly used assumption of viewing CNTs as straight cylinders leads to significant overestimation of the overall medium conductivity. The CNT length has an important effect on the nanofluid conductivity for all types of CNT shapes considered here. In addition, use of CNTs with higher conductivity than a certain value appears to have no further beneficial effect, thus relaxing the need for extremely pure or single-wall CNTs. On the contrary, the conductivity remains a strong function of the CNT concentration and may be even increased upon organization of CNTs into loose clusters. The overall approach and concept can be extended to CNT composites in a straightforward manner.
Thiazolidinedione-Conjugated Lupeol Derivatives as Potent Anticancer Agents Through a Mitochondria-Mediated Apoptotic Pathway
Authors: Deng Siqi , Zhao Yinxu , Guo Xiaoshan , Hong Xian , Li Gang , Wang Yuchun , Li Qingyi , Bu Ming , Wang Ming
Published: October 2024

To improve the potential of lupeol against cancer cells, a privileged structure, thiazolidinedione, was introduced into its C-3 hydroxy group with ester, piperazine-carbamate, or ethylenediamine as a linker, and three series of thiazolidinedione-conjugated compounds (6a–i, 9a–i, and 12a–i) were prepared. The target compounds were evaluated for their cytotoxic activities against human lung cancer A549, human breast cancer MCF-7, human hepatocarcinoma HepG2, and human hepatic LO2 cell lines, and the results revealed that most of the compounds displayed improved potency over lupeol. Compound 12i exhibited significant activity against the HepG2 cell line, with an IC50 value of 4.40 μM, which is 9.9-fold more potent than lupeol (IC50 = 43.62 μM). Mechanistic studies suggested that 12i could induce HepG2 cell apoptosis, as evidenced by AO/EB staining and annexin V-FITC/propidium iodide dual staining assays. Western blot analysis suggested that compound 12i can upregulate Bax expression, downregulate Bcl-2 expression, and activate the mitochondria-mediated apoptotic pathway. Collectively, compound 12i is worthy of further investigation to support the discovery of effective agents against cancer.
Virucidal Coatings Active Against SARS-CoV-2
Authors: Barabanova Anna I. , Karamov Eduard V. , Larichev Viktor F. , Kornilaeva Galina V. , Fedyakina Irina T. , Turgiev Ali S. , Naumkin Alexander V. , Lokshin Boris V. , Shibaev Andrey V. , Potemkin Igor I. , Philippova Olga E.
Published: October 2024

Three types of coatings (contact-based, release-based, and combined coatings with both contact-based and release-based actions) were prepared and tested for the ability to inactivate SARS-CoV-2. In these coatings, quaternary ammonium surfactants were used as active agents since quaternary ammonium compounds are some of the most commonly used disinfectants. To provide contact-based action, the glass and silicon surfaces with covalently attached quaternary ammonium cationic surfactant were prepared using a dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride modifier. Surface modification was confirmed by attenuated total reflection infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and contact angle measurements. The grafting density of the modifier was estimated by XPS and elemental analysis. To provide release-based action, the widely used quaternary ammonium cationic disinfectant, benzalkonium chloride (BAC), and a newly synthesized cationic gemini surfactant, C18-4-C18, were bound non-covalently to the surface either through hydrophobic or electrostatic interactions. Virus titration revealed that the surfaces with combined contact-based and release-based action and the surfaces with only release-based action completely inactivate SARS-CoV-2. Coatings containing only covalently bound disinfectant are much less effective; they only provide up to 1.25 log10 reduction in the virus titer, probably because of the low disinfectant content in the surface monolayer. No pronounced differences in the activity between the flat and structured surfaces were observed for any of the coatings under study. Comparative studies of free and electrostatically bound disinfectants show that binding to the surface of nanoparticles diminishes the activity. These data indicate that SARS-CoV-2 is more sensitive to the free disinfectants.
A Comparative Study of the Chemical Composition and Skincare Activities of Red and Yellow Ginseng Berries
Authors: Wang Yu-Dan , Han Lu-Sheng , Li Gen-Yue , Yang Kai-Li , Shen Yan-Long , Zhang Hao , Hou Jian-Feng , Wang En-Peng
Published: October 2024

This study was conducted to investigate the differences in chemical composition between red (RGBs) and yellow ginseng berries (YGBs) and their whitening and anti-aging skincare effects. The differences in the chemical composition between RGB and YGB were analyzed by ultra-high-performance liquid chromatography tandem quadrupole electrostatic field orbit trap mass spectrometry (UHPLC-Q-Exactive-MS/MS) combined with multivariate statistics. An aging model was established using UVB radiation induction, and the whitening and anti-aging effects of the two ginseng berries were verified in vitro and in vivo using cell biology (HaCaT and B16-F10 cells) and zebrafish model organisms. A total of 31 differential compounds, including saponins, flavonoids, phenolic acids, and other chemical constituents, were identified between the two groups. Superoxide dismutase (SOD) activity was more significantly increased (p < 0.05) and malondialdehyde (MDA) content was more significantly decreased (p < 0.01) in RGB more than YGB induced by UVB ultraviolet radiation. In terms of whitening effects, YGB was more effective in inhibiting the melanin content of B16-F10 cells (p < 0.01). The results of zebrafish experiments were consistent with those of in vitro experiments and cell biology experiments. The DCFH fluorescence staining results revealed that both ginseng berries were able to significantly reduce the level of reactive oxygen species (ROS) in zebrafish (p < 0.01). Comparison of chemical composition and skin care activities based on RGB and YGB can provide a theoretical basis for the deep development and utilization of ginseng berry resources.
Protein A-like Peptide Design Based on Diffusion and ESM2 Models
Authors: Zhao Long , He Qiang , Song Huijia , Zhou Tianqian , Luo An , Wen Zhenguo , Wang Teng , Lin Xiaozhu
Published: October 2024

Proteins are the foundation of life, and designing functional proteins remains a key challenge in biotechnology. Before the development of AlphaFold2, the focus of design was primarily on structure-centric approaches such as using the well-known open-source software Rosetta3. Following the development of AlphaFold2, deep-learning techniques for protein design gained prominence. This study proposes a new method to generate functional proteins using the diffusion model and ESM2 protein language model. Diffusion models, which are widely used in image and natural language generation, are used here for protein design, facilitating the controlled generation of new sequences. The ESM2 model, trained on the basis of large-scale protein sequence data, provides a deep understanding of the context of the sequence, thus improving the model’s ability to generate biologically relevant proteins. In this study, we used the Protein A-like peptide as a model study object, combined the diffusion model and the ESM2 model to generate new peptide sequences from minimal input data, and verified their biological activities through experiments such as the BLI affinity test. In conclusion, we developed a new method for protein design that provides a novel strategy to meet the challenges of generic protein generation.
A Spin-Labeled Derivative of Gossypol
Authors: Stepanov Andrey V. , Yarovenko Vladimir N. , Nasyrova Darina I. , Dezhenkova Lyubov G. , Akchurin Igor O. , Krayushkin Mickhail M. , Ilyushenkova Valentina V. , Shchekotikhin Andrey E. , Tretyakov Evgeny V.
Published: October 2024

Gossypol and its derivatives arouse interest due to their broad spectrum of biological activities. Despite its wide potential application, there is no reported example of gossypol derivatives bearing stable radical functional groups. The first gossypol nitroxide hybrid compound was prepared here via formation of a Schiff base. By this approach, synthesis of a gossypol nitroxide conjugate was performed by condensation of gossypol with a 4-amino-TEMPO (4-amino-2,2,6,6-tetramethylpiperidin-1-oxyl) free radical, which afforded the target product in high yield. Its structure was proven by a combination of NMR and EPR spectroscopy, infrared spectroscopy, mass spectrometry, and high-resolution mass spectrometry. In addition, the structure of the gossypol nitroxide was determined by single-crystal X-ray diffraction measurements. In crystals, the paramagnetic Schiff base exists in an enamine–enamine tautomeric form. The tautomer is strongly stabilized by the intra- and intermolecular hydrogen bonds promoted by the resonance of π-electrons in the aromatic system. NMR analyses of the gossypol derivative proved that in solutions, the enamine–enamine tautomeric form prevailed. The gossypol nitroxide at micromolar concentrations suppressed the growth of tumor cells; however, compared to gossypol, the cytotoxicity of the obtained conjugate was substantially lower.
Integrating Epoxidation, High-Resolution Mass Spectrometry and Ultraviolet Spectroscopy to Unravel the Complex Profile of Boswellic Acids and Related Compounds in the Boswellia serrata Gum Resin Extract
Authors: Castellaneta Andrea , Losito Ilario , Cometa Stefania , Busto Francesco , De Giglio Elvira , Cataldi Tommaso R. I.
Published: October 2024

The chemical characterization of natural products is often a complex task that demands powerful analytical techniques. Liquid chromatography with high-resolution tandem mass spectrometry (HRMS/MS) is often employed, yet it can face hard challenges when isomeric species are present, and reference standards are lacking. In such cases, the confidence level in compound identification can be significantly improved by the collection of orthogonal information on target analytes. In this work, 23 key compounds in Boswellia serrata extract (BSE), 12 of which correspond to boswellic acids (BAs) and 11 to triterpenoidic acid isomers, were identified by combining RPLC followed by serial UV and ESI(-)-FTMS and FTMS/MS detections with the evaluation of the reactivity towards C=C bond epoxidation with meta-chloroperoxybenzoic acid (m-CPBA), proposed as a fast chemical tool to gather information about C=C bond steric hindrance, a key structural feature of BAs and related compounds. The interpretation of UV spectra acquired after chromatographic separation corroborated the identification of the substitution patterns of enonic and dienic residues in ketoboswellic and dehydroboswellic acids. Moreover, MS/MS based on higher-energy collision-induced dissociation (HCD) unveiled new fragmentation pathways, providing important structural details on target analytes. The integrated approach developed during this study might pave the way for a deeper understanding of the BSE bioactive properties. Moreover, it can be considered an example of a more general strategy for the analysis of complex mixtures of natural compounds including also isomeric species.