bluuebunny/crossref_metadata_2025 huggingface dataset:
A Fluorescence-Based Method to Measure ADP/ATP Exchange of Recombinant Adenine Nucleotide Translocase in Liposomes
Authors: Kreiter Jürgen , Beitz Eric , Pohl Elena E.
Published: April 2020

Several mitochondrial proteins, such as adenine nucleotide translocase (ANT), aspartate/glutamate carrier, dicarboxylate carrier, and uncoupling proteins 2 and 3, are suggested to have dual transport functions. While the transport of charge (protons and anions) is characterized by an alteration in membrane conductance, investigating substrate transport is challenging. Currently, mainly radioactively labeled substrates are used, which are very expensive and require stringent precautions during their preparation and use. We present and evaluate a fluorescence-based method using Magnesium Green (MgGrTM), a Mg2+-sensitive dye suitable for measurement in liposomes. Given the different binding affinities of Mg2+ for ATP and ADP, changes in their concentrations can be detected. We obtained an ADP/ATP exchange rate of 3.49 ± 0.41 mmol/min/g of recombinant ANT1 reconstituted into unilamellar liposomes, which is comparable to values measured in mitochondria and proteoliposomes using a radioactivity assay. ADP/ATP exchange calculated from MgGrTM fluorescence solely depends on the ANT1 content in liposomes and is inhibited by the ANT-specific inhibitors, bongkrekic acid and carboxyatractyloside. The application of MgGrTM to investigate ADP/ATP exchange rates contributes to our understanding of ANT function in mitochondria and paves the way for the design of other substrate transport assays.
Functional Implications of Cathelicidin Antimicrobial Protein in Breast Cancer and Tumor-Associated Macrophage Microenvironment
Authors: Chen Jiawei , Shin Vivian Yvonne , Ho John Chi-Wang , Siu Man-Ting , Cheuk Isabella Wai-Yin , Kwong Ava
Published: April 2020

It is well-established that tumor-associated macrophages (TAMs) play an important role in breast cancer development. Accumulating evidence suggested that human cathelicidin antimicrobial protein (CAMP), which is mainly expressed in host defense cells such as macrophages, is crucial not only in combating microorganisms but also promoting tumor growth. Here we report the interaction of CAMP with TAMs in breast cancer. CAMP expression was upregulated in cancer tissues and in the circulation of breast cancer patients. Surgical removal of tumor decreased CAMP peptide serum level. Knockdown of CAMP decreased cell proliferation and migration/invasion ability in breast cancer cells. CAMP expression was altered during macrophage M1/M2 polarization and was expressed predominantly in M2 phenotype. In addition, breast cancer cells co-cultured with macrophages upregulated CAMP expression and also increased cancer cell viability. Xenograft tumors reduced significantly upon CAMP receptor antagonist treatment. Our data implicated that CAMP confers an oncogenic role in breast cancer and plays an important role in the tumor microenvironment between TAMs and breast cancer cells, and blocking the interaction between them would provide a novel therapeutic option for this malignant disease.
Daily Application of a Toothpaste with Biomimetic Hydroxyapatite and Its Subjective Impact on Dentin Hypersensitivity, Tooth Smoothness, Tooth Whitening, Gum Bleeding, and Feeling of Freshness
Authors: Steinert Sonja , Zwanzig Kai , Doenges Helga , Kuchenbecker Joern , Meyer Frederic , Enax Joachim
Published: April 2020

The aim of this observational study was to analyze the effect of a toothpaste with biomimetic zinc hydroxyapatite (HAP) on subjective parameters after a four-week home use. Patients with subjective dentin hypersensitivity were recruited at three dental practices in Germany and received a questionnaire with visual analogue scales and Likert scales both at baseline and follow-up. The questionnaire was specifically developed for this study and focused on questions about subjective parameters like dentin hypersensitivity, tooth surface texture, tooth color, and freshness after toothbrushing. Patients answered the questionnaire both at baseline and after a four-week home use (follow-up) of the HAP toothpaste. Data of 46 patients were analyzed by paired t-test and non-parametric Wilcoxon signed-rank test, respectively. Subjective parameters on dentin hypersensitivity were reduced after the four-week use of the HAP toothpaste (p < 0.001). Additionally, patients assessed their tooth surface as smoother (p < 0.001), tooth color as whiter (p = 0.003), and reported a stronger feeling of freshness after toothbrushing (p = 0.014) after four-week use of the HAP toothpaste compared to the previously used toothpaste. In conclusion, the tested toothpaste with biomimetic HAP is well-suited for individuals suffering from dentin hypersensitivity, because subjective symptoms on dentin hypersensitivity were reduced. Additionally, patients reported smoother and whiter teeth after using the HAP toothpaste.
Multiple Soliton Interactions on the Surface of Deep Water
Authors: Kachulin Dmitry , Dyachenko Alexander , Dremov Sergey
Published: April 2020

The paper presents the long-time dynamics with multiple collisions of breathers in the super compact Zakharov equation for unidirectional deep water waves. Solutions in the form of breathers were found numerically by the Petviashvili method. In the terms of envelope and the assumption of the narrow spectral width the super compact equation turns into the well known exact integrable model—nonlinear Schrödinger equation, and the breather solution in this case turns into envelope soliton. The results of numerical simulations show that two main scenarios of long-time dynamics occur during numerous collisions of breathers. In the first case, one of the breathers regularly takes a number of particles from the other one at each collision and in the second one a structure resembling the bi-soliton solution of nonlinear Schrödinger equation arises during the collision. Despite these scenarios, it is shown that after numerous collisions the only one breather having initially a larger number of particles remains.
Rotation Curve of the Milky Way and the Dark Matter Density
Authors: Sofue Yoshiaki
Published: April 2020

We review the current status of the study of rotation curve (RC) of the Milky Way, and present a unified RC from the Galactic Center to the galacto-centric distance of about 100 kpc. The RC is used to directly calculate the distribution of the surface mass density (SMD). We then propose a method to derive the distribution of dark matter (DM) density in the in the Milky Way using the SMD distribution. The best-fit dark halo profile yielded a local DM density of ρ ⊙ = 0.36 ± 0.02 GeV cm − 3 . We also review the estimations of the local DM density in the last decade, and show that the value is converging to a value at ρ ⊙ = 0.39 ± 0.09 GeV cm − 3 .
Evaluation and Calibration of Alternative Methods for Estimating Reference Evapotranspiration in the Senegal River Basin
Authors: Ndiaye Papa Malick , Bodian Ansoumana , Diop Lamine , Deme Abdoulaye , Dezetter Alain , Djaman Koffi
Published: April 2020

Reference evapotranspiration (ET0) is a key element of the water cycle in tropical areas for the planning and management of water resources, hydrological modeling, and irrigation management. The objective of this research is to assess twenty methods in computing ET0 in the Senegal River Basin and to calibrate and validate the best methods that integrate fewer climate variables. The performance of alternative methods compared to the Penman Monteith (FAO56-PM) model is evaluated using the coefficient of determination (R2), normalized root mean square error (NRMSE), percentage of bias (PBIAS), and the Kling–Gupta Efficiency (KGE). The most robust methods integrating fewer climate variables were calibrated and validated and the results show that Trabert, Valiantzas 2, Valiantzas 3, and Hargreaves and Samani models are, respectively, the most robust for ET0 estimation. The calibration improves the estimates of reference evapotranspiration compared to original models. It improved the performance of these models with an increase in KGE values of 45%, 32%, 29%, and 19% for Trabert, Valiantzas 2, Valiantzas 3, and Hargreaves and Samani models, respectively. From a spatial point of view, the calibrated models of Trabert and Valiantzas 2 are robust in all the climatic zones of the Senegal River Basin, whereas, those of Valiantzas 3 and Hargreaves and Samani are more efficient in the Guinean zone. This study provides information on the choice of a model for estimating evapotranspiration in the Senegal River Basin.
Advances in Dam Engineering
Authors: Hariri-Ardebili Mohammad Amin , Salamon Jerzy , Mazza Guido , Tosun Hasan , Xu Bin
Published: April 2020

The expansion of water resources is the key factor in the socio-economic development of all countries [...]
Dynamic Rounding Stability in Through-Feed Centerless Grinding
Authors: Hashimoto Fukuo
Published: April 2020

The through-feed method in centerless grinding allows manufacturers to produce cylindrical parts at much higher levels of productivity than can be achieved with in-feed grinding, so it has been extensively employed in industry. However, its rounding mechanism is not yet well understood due to the complexity of the through-feed process. This paper presents the fundamental parameters, such as material removal rates, forces, and so on in the through-feed grinding, and analyses on the grinding system with feedback loops, including regenerative functions and the machine dynamic functions. Further, the characteristic roots of the system, representing the number of waves and the growth rates of the harmonics in roundness, are identified at each grinding position from entry to exit. To evaluate the grinding process stability, a rounding stability index (RSI) was proposed. It was demonstrated that the analytical tool modeled in this paper can identify the optimum operational conditions by the RSI for achieving desired grinding productivity and accuracy. Finally, the model is verified with grinding tests, and the nm-order roundness obtained by the tests is shown.
Correction: Etelcalcetide in Patients on Hemodialysis with Severe Secondary Hyperparathyroidism. Multicenter Study in “Real Life”. J. Clin. Med. 2019, 8, 1066
Authors: Russo Domenico , Tripepi Rocco , Malberti Fabio , Di Iorio Biagio , Scognamiglio Bernadette , Di Lullo Luca , Paduano Immacolata Gaia , Tripepi Giovanni Luigi , Panuccio Vincenzo Antonio
Published: April 2020

The authors wish to make the following corrections to the previous publication [...]
On Estimating the Hurst Parameter from Least-Squares Residuals. Case Study: Correlated Terrestrial Laser Scanner Range Noise
Authors: Kermarrec Gaël
Published: April 2020

Many signals appear fractal and have self-similarity over a large range of their power spectral densities. They can be described by so-called Hermite processes, among which the first order one is called fractional Brownian motion (fBm), and has a wide range of applications. The fractional Gaussian noise (fGn) series is the successive differences between elements of a fBm series; they are stationary and completely characterized by two parameters: the variance, and the Hurst coefficient (H). From physical considerations, the fGn could be used to model the noise of observations coming from sensors working with, e.g., phase differences: due to the high recording rate, temporal correlations are expected to have long range dependency (LRD), decaying hyperbolically rather than exponentially. For the rigorous testing of deformations detected with terrestrial laser scanners (TLS), the correct determination of the correlation structure of the observations is mandatory. In this study, we show that the residuals from surface approximations with regression B-splines from simulated TLS data allow the estimation of the Hurst parameter of a known correlated input noise. We derive a simple procedure to filter the residuals in the presence of additional white noise or low frequencies. Our methodology can be applied to any kind of residuals, where the presence of additional noise and/or biases due to short samples or inaccurate functional modeling make the estimation of the Hurst coefficient with usual methods, such as maximum likelihood estimators, imprecise. We demonstrate the feasibility of our proposal with real observations from a white plate scanned by a TLS.
The Cytotoxic and Apoptotic Effects of the Brown Algae Colpomenia sinuosa are Mediated by the Generation of Reactive Oxygen Species
Authors: Al Monla Reem , Dassouki Zeina , Kouzayha Achraf , Salma Yahya , Gali-Muhtasib Hala , Mawlawi Hiba
Published: April 2020

Brown algae are a novel resource of biogenic molecules, however few studies have been conducted in the Mediterranean to assess the cytotoxic mechanisms of algal-derived compounds. This study focuses on the antineoplastic activity of extracts from non-investigated algae of the Lebanese coast, Colpomenia sinuosa. Extracts’ antineoplastic activities were evaluated by MTT and trypan blue on different tumorigenic cells. Results indicated that the most potent extract was obtained by soxhlet using dichloromethane:methanol solvent (DM soxhlet) against HCT-116. Wound healing assay confirmed that this extract decreased the migration potential of HCT-116 cells with minimal effects on non-tumorigenic cells. It also induced an increase in the subG1 population as determined by flow cytometry. Western blot analysis demonstrated that apoptosis in treated HCT-116 cells was induced via upregulation of p21 protein and downregulation of the anti-apoptotic Bcl 2, which led to caspases activation. The latter, catalyzes the degradation of PARP-1, and thus suppresses cancer proliferation. Morphological alterations, further confirmed apoptosis. A strong pro-oxidant activity evidenced by the enhanced generation of reactive oxygen species (ROS) was observed in HCT-116 treated cells. Interestingly, a strong antioxidant effectively blocked effect induced by the extract. These results indicate that C. sinuosa is a source of bioactive compounds possessing pro-apoptotic and anti-migratory efficacy.
Potential Antimicrobial and Anticancer Activities of an Ethanol Extract from Bouea macrophylla
Authors: Nguyen Ngoc Hong , Nguyen Thuy Trang , Ma Phu Cuong , Ta Qui Thanh Hoai , Duong Thuc-Huy , Vo Van Giau
Published: April 2020

Bouea macrophylla is a tree widely grown throughout South East Asia. It is used in folk medicine for the treatment of various illnesses. The present study aimed to identify the chemical constituents and to test the antimicrobial and anticancer activities of an ethanol extract from B. macrophylla leaves. The extract exhibited excellent antibacterial properties against 9 out of 10 target microorganisms. including four Gram-negative bacteria (Escherichia coli, Shigella flexneri, Vibrio cholera, and Pseudomonas aeruginosa) and four Gram-positive bacteria (Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis, and Bacillus cereus), as well as a fungus (Candida albicans). In addition, the extract was also tested on HeLa and human colorectal carcinoma (HCT116) cells to evaluate its cytostatic effects. The ethanol extract was able to inhibit the proliferation of HeLa and HCT116 cells, showing IC50 = 24 ± 0.8 and 28 ± 0.9 µg/mL, respectively, whereas the IC50 values of doxorubicin (standard) were 13.6 ± 1.3 and 15.8 ± 1.1 µg/mL respectively. Also, we identified various bioactive compounds in the extract such as polyphenols, flavonoids, caryophyllene, phytol, and trans-geranylgeraniol by GC-MS, which could contribute to the extract’s biological activities. Therefore, our findings strongly indicate that the constituents of the B. macrophylla ethanol extract could be active against the tested bacteria and fungi as well as cancer cells. Further investigation is needed to understand the mechanisms mediating the antimicrobial and anticancer effects and identify signaling pathways that could be targeted for therapeutic application.
Viral Hepatitis and Iron Dysregulation: Molecular Pathways and the Role of Lactoferrin
Authors: Mancinelli Romina , Rosa Luigi , Cutone Antimo , Lepanto Maria Stefania , Franchitto Antonio , Onori Paolo , Gaudio Eugenio , Valenti Piera
Published: April 2020

The liver is a frontline immune site specifically designed to check and detect potential pathogens from the bloodstream to maintain a general state of immune hyporesponsiveness. One of the main functions of the liver is the regulation of iron homeostasis. The liver detects changes in systemic iron requirements and can regulate its concentration. Pathological states lead to the dysregulation of iron homeostasis which, in turn, can promote infectious and inflammatory processes. In this context, hepatic viruses deviate hepatocytes’ iron metabolism in order to better replicate. Indeed, some viruses are able to alter the expression of iron-related proteins or exploit host receptors to enter inside host cells. Lactoferrin (Lf), a multifunctional iron-binding glycoprotein belonging to the innate immunity, is endowed with potent antiviral activity, mainly related to its ability to block viral entry into host cells by interacting with viral and/or cell surface receptors. Moreover, Lf can act as an iron scavenger by both direct iron-chelation or the modulation of the main iron-related proteins. In this review, the complex interplay between viral hepatitis, iron homeostasis, and inflammation as well as the role of Lf are outlined.
Antimicrobial Peptides as Probes in Biosensors Detecting Whole Bacteria: A Review
Authors: Pardoux Éric , Boturyn Didier , Roupioz Yoann
Published: April 2020

Bacterial resistance is becoming a global issue due to its rapid growth. Potential new drugs as antimicrobial peptides (AMPs) are considered for several decades as promising candidates to circumvent this threat. Nonetheless, AMPs have also been used more recently in other settings such as molecular probes grafted on biosensors able to detect whole bacteria. Rapid, reliable and cost-efficient diagnostic tools for bacterial infection could prevent the spread of the pathogen from the earliest stages. Biosensors based on AMPs would enable easy monitoring of potentially infected samples, thanks to their powerful versatility and integrability in pre-existent settings. AMPs, which show a broad spectrum of interactions with bacterial membranes, can be tailored in order to design ubiquitous biosensors easily adaptable to clinical settings. This review aims to focus on the state of the art of AMPs used as the recognition elements of whole bacteria in label-free biosensors with a particular focus on the characteristics obtained in terms of threshold, volume of sample analysable and medium, in order to assess their workability in real-world applications.
Effect of Saturated Steam Heat Treatment on Physical and Chemical Properties of Bamboo
Authors: Wang Qiuyi , Wu Xinwu , Yuan Chenglong , Lou Zhichao , Li Yanjun
Published: April 2020

The aim of this study was to investigate the effects of the heat treatment time and initial moisture content of bamboo on the corresponding chemical composition, crystallinity, and mechanical properties after saturated steam heat treatment at 180 °C. The mechanism of saturated steam heat treatment of bamboo was revealed on the micro-level, providing a theoretical basis for the regulation of bamboo properties and the optimization of heat treatment process parameters. XRD patterns of the treated bamboo slices were basically the same. With the increase in the initial moisture content of bamboo, the crystallinity of bamboo increased first and then decreased after treatment. Due to the saturated steam heat treatment, the content of cellulose and lignin in bamboo slices increased while the content of hemicellulose decreased, but the content of cellulose in bamboo with a 40% initial moisture content increased first and then decreased. The shear strength of treated bamboo changed little within 10 min after saturated steam heat treatment, and then decreased rapidly. During the first 20 min with saturated steam heat treatment, the compressive strength, flexural strength, and flexural modulus of elasticity of the treated bamboo increased, and then decreased.
Metallurgical Preparation of Nb–Al and W–Al Intermetallic Compounds and Characterization of Their Microstructure and Phase Transformations by DTA Technique
Authors: Cegan Tomas , Petlak Daniel , Skotnicova Katerina , Jurica Jan , Smetana Bedrich , Zla Simona
Published: April 2020

The possibilities of metallurgical preparation of 40Nb-60Al and 15W-85Al intermetallic compounds (in at.%) by plasma arc melting (PAM) and vacuum induction melting (VIM) were studied. Both methods allow easy preparation of Nb–Al alloys; however, significant evaporation of Al was observed during the melting, which affected the resulting chemical composition. The preparation of W–Al alloys was more problematic because there was no complete re-melting of W during PAM and VIM. However, the combination of PAM and VIM allowed the preparation of W–Al alloy without any non-melted parts. The microstructure of Nb–Al alloys consisted of Nb2Al and NbAl3 intermetallic phases, and W–Al alloys consisted mainly of needle-like WAl4 intermetallic phase and Al matrix. The effects of melting conditions on chemical composition, homogeneity, and microstructure were determined. Differential thermal analysis was used to determine melting and phase transformation temperatures of the prepared alloys.
High-Throughput Computational Search for Half-Metallic Oxides
Authors: Liyanage Laalitha S. I. , Sławińska Jagoda , Gopal Priya , Curtarolo Stefano , Fornari Marco , Buongiorno Nardelli Marco
Published: April 2020

Half metals are a peculiar class of ferromagnets that have a metallic density of states at the Fermi level in one spin channel and simultaneous semiconducting or insulating properties in the opposite one. Even though they are very desirable for spintronics applications, identification of robust half-metallic materials is by no means an easy task. Because their unusual electronic structures emerge from subtleties in the hybridization of the orbitals, there is no simple rule which permits to select a priori suitable candidate materials. Here, we have conducted a high-throughput computational search for half-metallic compounds. The analysis of calculated electronic properties of thousands of materials from the inorganic crystal structure database allowed us to identify potential half metals. Remarkably, we have found over two-hundred strong half-metallic oxides; several of them have never been reported before. Considering the fact that oxides represent an important class of prospective spintronics materials, we have discussed them in further detail. In particular, they have been classified in different families based on the number of elements, structural formula, and distribution of density of states in the spin channels. We are convinced that such a framework can help to design rules for the exploration of a vaster chemical space and enable the discovery of novel half-metallic oxides with properties on demand.
Phytochemical Profile and Biological Activity of Endemic Sideritis sipylea Boiss. in North Aegean Greek Islands
Authors: Axiotis Evangelos , Petrakis Eleftherios A. , Halabalaki Maria , Mitakou Sofia
Published: April 2020

Sideritis sipylea Boiss. is an endemic plant of the Mediterranean basin that is distributed in the Greek islands of the North Aegean Sea, i.e., Lesvos, Chios, Samos, and Ikaria, and in the West and Middle peninsula of Turkey. It is considered an endangered species because of its uncontrolled collection from its original habitat. Although the antioxidant, anti-inflammatory and antimicrobial properties have been previously reported, the total chemical profile has not yet been explored. In this context, the chemical profiles of the water/methanol (HA), methanol (ME), and ethyl acetate (EtOAc) extracts were analyzed using ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS). In parallel, analysis by gas chromatography-mass spectrometry (GC-MS) was employed for the dichloromethane extract (DCM) as well as for the essential oil (EO) and the extract obtained by supercritical fluid extraction (SFE). Furthermore, the total phenolic content (TPC) along with the in vitro tyrosinase and elastase enzyme inhibitory activity of different extracts was evaluated, towards the discovery of new active agents for cosmetic formulations. These activities are in accordance with its well-known antioxidant and anti-inflammatory properties, confirming the importance of ethnopharmacological references for S. sipylea in Greece and Turkey.
Anti-Acne Action of Peptides Isolated from Burdock Root—Preliminary Studies and Pilot Testing
Authors: Miazga-Karska Malgorzata , Michalak Katarzyna , Ginalska Grazyna
Published: April 2020

This work aimed to study the anti-bacterial, anti-biofilm and anti-oxidant potential effects of low molecular weight (LMW) peptides (Br-p) isolated from burdock (Arctium lappa L.) roots. We conducted a preliminary study to exclude or confirm the antibiotic activity of the LMW peptides fraction of this plant. Br-p were isolated using gel filtration and a 10 kDa cut-off membrane. The obtained peptides were identified by MALDI TOF/TOF. Antibacterial activity was tested against acne strains using diffusion tests, MIC and MBC. The fibroblast cytotoxicity of Br-p was tested, and the selectivity index (SI) value was determined. The fraction of 46 Br-p peptides isolated from burdock root with a molecular weight below 5000 Da and theoretic pI (isoelectric point) of 3.67–11.83 showed a narrow spectrum of activity against Gram-positive acne bacterial strains. One of the Br-p peptides assessed on MALDI RapidDeNovo was LRCDYGRFFASKSLYDPLKKRR cationic peptide. It was analogous to that contained in A. lappa protein, and theoretically it was matched as a peptide with antibiotic nature. Br-p did not show toxicity to fibroblasts in the tested concentration up to 10 mg/mL, obtaining CC50 10 mg/mL. The SI value for the tested Propionibacterium strains ranged from 160 to 320. Finally, an active dressing based on chitosan/alginate/genipin was prepared using freeze-drying. The formed dressing was evaluated for its anti-acne activity. To sum up: preliminary biological studies confirmed the anti-acne properties of the isolated peptide fraction from burdock root and pointed to the possibility of using it to create an active dressing on the skin.
Effect of Angelica gigas Nakai Ethanol Extract and Decursin on Human Pancreatic Cancer Cells
Authors: Kweon Bitna , Han Yo-Han , Kee Ji-Ye , Mun Jeong-Geon , Jeon Hee Dong , Yoon Dae Hwan , Choi Byung-Min , Hong Seung-Heon
Published: April 2020

Pancreatic cancer (PC) is one of the most severe cancers, and its incidence and mortality rates have steadily increased in the past decade. In this study, we demonstrate the effect of Angelica gigas Nakai extract on pancreatic ductal adenocarcinoma cells. We prepared A. gigas Nakai ethanol extract (AGE) using roots of A. gigas Nakai and detected its active compound decursin from AGE by ultra-performance liquid chromatography analysis. AGE and decursin significantly decreased viability and colony formation of PANC-1 and MIA PaCa-2 cells. AGE and decursin induced G0/G1 phase arrest through downregulation of cyclin D1 and cyclin-dependent kinase 4 (CDK4). Caspase-3-dependent apoptosis of PANC-1 cells was promoted by AGE and decursin. Additionally, nontoxic concentrations of AGE and decursin treatment could suppress matrix metalloproteinase (MMP)-2 and MMP-9 expression and activity by inhibiting p38 phosphorylation. Taken together, this study demonstrates that AGE and decursin have potential properties to be considered in PC treatment.
Special Issue: Biogenic Nanomaterials: Versatility and Applications
Authors: Jeffryes Clayton , Dahoumane Si Amar
Published: April 2020

Greener processes have emerged as serious and competitive routes to produce various nanomaterials [...]
Syntheses, Reactivities, Characterization, and Crystal Structures of Dipalladium Complexes Containing the 1,3-pyrimidinyl Ligand: Structures of [Pd(PPh3)(Br)]2(μ,η2-C4H3N2)2, [Pd(Br)]2(μ,η2-Hdppa)2, and [{Pd(PPh3)(CH3CN)}2(μ,η2-C4H3N2)2][BF4]2
Authors: Wang Hsiao-Fen , Yih Kuang-Hway , Lee Gene-Hsiang
Published: April 2020

In a refluxing chloroform solution, the η1-pyrimidinyl {pyrimidinyl = C4H3N2} palladium complex [Pd(PPh3)2(η1-C4H3N2)(Br)], 1 exhibited intermolecular displacement of two triphenylphosphine ligands to form the doubly bridged η2-pyrimidinyl Dipalladium complex [Pd(PPh3)(Br)]2(μ,η2-C4H3N2)2, 3. The treatment of 1 with Hdppa {Hdppa = N,N-bisdiphenyl phosphinoamine} in refluxing dichloromethane yielded the doubly bridged Hdppa dipalladium complex [Pd(Br)]2(μ,η2-Hdppa)2, 4. Complex 1 reacted with the bidentate ligand, NH4S2CNC4H8 and, NaS2COEt, and the tridentate ligand, KTp {Tp = tris(pyrazoyl-1-yl)borate}, to form the η2-dithio η1-pyrimidinyl complex [Pd(PPh3)(η1-C4H3N2)(η2-SS)], (5: SS = S2CNC4H8; 6: SS = S2COEt) and η2-Tp η1-pyrimidinyl complex [Pd(PPh3)(η1-C4H3N2)(η2-Tp)], 7, respectively. Treatment of 1 with AgBF4 in acetonitrile at room temperature resulted in the formation of the doubly bridged η2-pyrimidinyl dipalladium complex [{Pd(PPh3)(CH3CN)}2(μ,η2-C4H3N2)2][BF4]2, 8. All of the complexes were identified using spectroscopic methods, and complexes 3, 4, and 8 were determined using single-crystal X-ray diffraction analyses.
Iron Absorption in Celiac Disease and Nutraceutical Effect of 7-Hydroxymatairesinol. Mini-Review
Authors: Zanella Isabella , Paiardi Giulia , Di Lorenzo Diego , Biasiotto Giorgio
Published: April 2020

Anemia is the main extra-gastrointestinal symptom in inflammatory bowel diseases (IBDs). Interleukin-6 (IL-6) and other cytokines are secreted and act in the microenvironment of the small intestine mucous membrane of IBD patients. Iron is essential for multiple cell functions and its homeostasis is regulated by the hepcidin–ferroportin axis. Hepcidin (HEPC) is mainly produced by the liver in response to iron needs but is also an acute phase protein. During inflammation, hepcidin is upregulated by IL-6 and is responsible for iron compartmentalization within cells, in turn causing anemia of inflammation. Tissues other than liver can produce hepcidin in response to inflammatory stimuli, in order to decrease iron efflux at a local level, then acting in an autocrine–paracrine manner. In IBDs and, in particular, in celiac disease (CeD), IL-6 might trigger the expression, upregulation and secretion of hepcidin in the small intestine, reducing iron efflux and exacerbating defective iron absorption. 7-Hydroxymatairesinol (7-HMR) belongs to the family of lignans, polyphenolic compounds produced by plants, and has nutraceutical antioxidant, anti-inflammatory and estrogenic properties. In this mini-review we revise the role of inflammation in IBDs and in particular in CeD, focusing our attention on the close link among inflammation, anemia and iron metabolism. We also briefly describe the anti-inflammatory and estrogenic activity of 7-HMR contained in foods that are often consumed by CeD patients. Finally, considering that HEPC expression is regulated by iron needs, inflammation and estrogens, we explored the hypothesis that 7-HMR consumption could ameliorate anemia in CeD using Caco-2 cells as bowel model. Further studies are needed to verify the regulation pathway through which 7-HMR may interfere with the local production of HEPC in bowel.
Physicochemical Properties and Bioactivity of a New Guar Gum-Based Film Incorporated with Citral to Brown Planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)
Authors: Gao Xiubing , Guo Can , Li Ming , Li Rongyu , Wu Xiaomao , Hu Anlong , Hu Xianfeng , Mo Feixu , Wu Shuai
Published: April 2020

The brown planthopper (BPH), Nilaparvata lugens (Stål), is the most notorious rice insect pest. In order to repel BPH effectively while being environmentally friendly, a new film based on guar gum incorporated with citral (GC film) was formulated. A toxicity bioassay of citral and guar gum at different proportions (ratios of 3:1, 2:1, 1:1, 1:2, and 1:3 in w/w) of GC film-forming emulsion to BPH was performed with the rice stem dipping method. Results showed that the most effective ratio of citral to guar gum was 1:1 with the median lethal concentration (LC50) of 4.30 mg/mL, far below the LC50 of guar gum (GG)/citral individual (141.51 and 44.38 mg/mL, respectively). The mortality of BPH adults and nymphs in the third instar treated with different dilution multiples of GC film-forming emulsion ranged from 46.67% to 82.22% and from 37.78% to 71.11%, respectively. These indicated that GC film-forming emulsion had a direct toxicity on BPH, and the mixture of citral and GG had synergistic interactions. Subsequently, Fourier-transform infrared spectroscopy showed that the incorporation of guar gum with citral was successful and did not result in the formation of new chemical bonds. The GC film exhibited a darker color and rougher surface topography with larger apertures and deeper gullies (Ra = 1.42 nm, Rq = 2.05 nm, and Rmax = 25.40 nm) compared to the guar gum film (GG film) (Ra = 1.00 nm, Rq = 1.33 nm, and Rmax = 16.40 nm), as determined by transmission electron microscopy and atomic force microscopy. The GC film exhibited a 50.4% lower solubility in water (30.30% vs. 15.00%) and 71.3% oxygen permeability (8.26 × 10−9 vs. 2.37 × 10−9 cm3/m2·d·Pa) (p < 0.05) but did not demonstrate any significant difference in mechanical properties, such as thickness (39.10 vs. 41.70 mm), tensile strength (41.89 vs. 38.30 N/mm2), and elongation at break (1.82% vs. 2.03%) (p < 0.05) compared to the GG film. Our findings established a link between physicochemical properties and bioactivity, which can provide useful information on developing and improving GC films and may offer an alternative approach for the control of BPH in the near future.
Comparison of Substituting Ability of Nitronate versus Enolate for Direct Substitution of a Nitro Group
Authors: Mukaijo Yusuke , Yokoyama Soichi , Nishiwaki Nagatoshi
Published: April 2020

α-Nitrocinnamate underwent the conjugate addition of an active methylene compound such as nitroacetate, 1,3-dicarbonyl compound, or α-nitroketone, and the following ring closure afforded functionalized heterocyclic frameworks. The reaction of cinnamate with nitroacetate occurs via nucleophilic substitution of a nitro group by the O-attack of the nitronate, which results in isoxazoline N-oxide. This protocol was applicable to 1,3-dicarbonyl compounds to afford dihydrofuran derivatives, including those derived from direct substitution of a nitro group caused by O-attack of enolate. It was found the reactivity was lowered by an electron-withdrawing group on the carbonyl moiety. When α-nitroketone was employed as a substrate, three kinds of products were possibly formed; of these, only isoxazoline N-oxide was identified. This result indicates that the substituting ability of nitronate is higher than that of enolate for the direct SN2 substitution of a nitro group.
An Efficient Synthetic Approach Towards Benzo[b]pyrano[2,3-e][1,4]diazepines, and Their Cytotoxic Activity
Authors: El Azab Islam H. , Elkanzi Nadia A.A.
Published: April 2020

In search of unprecedented tri and/or tetrapod pharmacophoric conjugates, a series of 32 new 4-ethyl-1H-benzo[b][1,4]diazepin-2(3H)-ones were synthesized and properly elucidated using MS, IR, NMR, and elemental analysis. In vitro investigation of 11 compounds of this series, using a panel of two human tumor cell lines namely; human breast adenocarcinoma (MCF-7), and human colorectal carcinoma (HCT-116), revealed promising cytotoxic activities. Among all synthesized compounds, analogue 9 displayed maximum cytotoxicity with IC50 values of 16.19 ± 1.35 and 17.16 ± 1.54 μM against HCT-116 and MCF-7, respectively, compared to standard drug doxorubicin.
Cooperative Analysis of Structural Dynamics in RNA-Protein Complexes by Single-Molecule Förster Resonance Energy Transfer Spectroscopy
Authors: Meiser Nathalie , Fuks Christin , Hengesbach Martin
Published: April 2020

RNA-protein complexes (RNPs) are essential components in a variety of cellular processes, and oftentimes exhibit complex structures and show mechanisms that are highly dynamic in conformation and structure. However, biochemical and structural biology approaches are mostly not able to fully elucidate the structurally and especially conformationally dynamic and heterogeneous nature of these RNPs, to which end single molecule Förster resonance energy transfer (smFRET) spectroscopy can be harnessed to fill this gap. Here we summarize the advantages of strategic smFRET studies to investigate RNP dynamics, complemented by structural and biochemical data. Focusing on recent smFRET studies of three essential biological systems, we demonstrate that investigation of RNPs on a single molecule level can answer important functional questions that remained elusive with structural or biochemical approaches alone: The complex structural rearrangements throughout the splicing cycle, unwinding dynamics of the G-quadruplex (G4) helicase RHAU, and aspects in telomere maintenance regulation and synthesis.
Flavonoids Distinctly Stabilize Lymph Endothelial- or Blood Endothelial Disintegration Induced by Colon Cancer Spheroids SW620
Authors: Berenda Julia , Smöch Claudia , Stadlbauer Christa , Mittermair Eva , Taxauer Karin , Huttary Nicole , Krupitza Georg , Krenn Liselotte
Published: April 2020

The health effects of plant phenolics in vegetables and other food and the increasing evidence of the preventive potential of flavonoids in “Western Diseases” such as cancer, neurodegenerative diseases and others, have gained enormous interest. This prompted us to investigate the effects of 20 different flavonoids of the groups of flavones, flavonols and flavanones in 3D in vitro systems to determine their ability to inhibit the formation of circular chemorepellent induced defects (CCIDs) in monolayers of lymph- or blood-endothelial cells (LECs, BECs; respectively) by 12(S)-HETE, which is secreted by SW620 colon cancer spheroids. Several compounds reduced the spheroid-induced defects of the endothelial barriers. In the SW620/LEC model, apigenin and luteolin were most active and acacetin, nepetin, wogonin, pinocembrin, chrysin and hispidulin showed weak effects. In the SW620/BEC model acacetin, apigenin, luteolin, wogonin, hispidulin and chrysin exhibited weak activity.
Structure-Activity-Relationship and Mechanistic Insights for Anti-HIV Natural Products
Authors: Kaur Ramandeep , Sharma Pooja , Gupta Girish K. , Ntie-Kang Fidele , Kumar Dinesh
Published: April 2020

Acquired Immunodeficiency Syndrome (AIDS), which chiefly originatesfroma retrovirus named Human Immunodeficiency Virus (HIV), has impacted about 70 million people worldwide. Even though several advances have been made in the field of antiretroviral combination therapy, HIV is still responsible for a considerable number of deaths in Africa. The current antiretroviral therapies have achieved success in providing instant HIV suppression but with countless undesirable adverse effects. Presently, the biodiversity of the plant kingdom is being explored by several researchers for the discovery of potent anti-HIV drugs with different mechanisms of action. The primary challenge is to afford a treatment that is free from any sort of risk of drug resistance and serious side effects. Hence, there is a strong demand to evaluate drugs derived from plants as well as their derivatives. Several plants, such as Andrographis paniculata, Dioscorea bulbifera, Aegle marmelos, Wistaria floribunda, Lindera chunii, Xanthoceras sorbifolia and others have displayed significant anti-HIV activity. Here, weattempt to summarize the main results, which focus on the structures of most potent plant-based natural products having anti-HIV activity along with their mechanisms of action and IC50 values, structure-activity-relationships and important key findings.
Computational NMR Spectroscopy of Ionic Liquids: [C4C1im]Cl/Water Mixtures
Authors: Saielli Giacomo
Published: April 2020

In this work, I have analyzed the structure of binary mixtures of 1-butyl-3-methylimidazolium chloride ionic liquid, [C4C1im]Cl, and water, using computational NMR spectroscopy. The structure of the complex fluid phase, where the ionic and hydrophobic nature of ionic liquids is further complicated by the addition of water, is first generated by classical Molecular Dynamics (MD) and then validated by calculating the NMR properties with DFT at the ONIOM(B3LYP/cc-pVTZ//B3LYP/3-21G) on clusters extracted during the MD trajectories. Three ionic liquid/water mixtures have been considered with the [C4C1im]Cl mole fraction of 1.00, 0.50, and 0.01, that is the pure ionic liquid [C4C1im]Cl, the equimolar [C4C1im]Cl/water mixture, and a diluted solution of [C4C1im]Cl in water. A good agreement is obtained with published experimental data that, at the same time, validates the structural features obtained from the MD and the force field used, and provides an example of the power of NMR spectroscopy applied to complex fluid phases.
Generation of Head Movements of a Robot Using Multimodal Features of Peer Participants in Group Discussion Conversation
Authors: Huang Hung-Hsuan , Kimura Seiya , Kuwabara Kazuhiro , Nishida Toyoaki
Published: April 2020

In recent years, companies have been seeking communication skills from their employees. Increasingly more companies have adopted group discussions during their recruitment process to evaluate the applicants’ communication skills. However, the opportunity to improve communication skills in group discussions is limited because of the lack of partners. To solve this issue as a long-term goal, the aim of this study is to build an autonomous robot that can participate in group discussions, so that its users can repeatedly practice with it. This robot, therefore, has to perform humanlike behaviors with which the users can interact. In this study, the focus was on the generation of two of these behaviors regarding the head of the robot. One is directing its attention to either of the following targets: the other participants or the materials placed on the table. The second is to determine the timings of the robot’s nods. These generation models are considered in three situations: when the robot is speaking, when the robot is listening, and when no participant including the robot is speaking. The research question is: whether these behaviors can be generated end-to-end from and only from the features of peer participants. This work is based on a data corpus containing 2.5 h of the discussion sessions of 10 four-person groups. Multimodal features, including the attention of other participants, voice prosody, head movements, and speech turns extracted from the corpus, were used to train support vector machine models for the generation of the two behaviors. The performances of the generation models of attentional focus were in an F-measure range between 0.4 and 0.6. The nodding model had an accuracy of approximately 0.65. Both experiments were conducted in the setting of leave-one-subject-out cross validation. To measure the perceived naturalness of the generated behaviors, a subject experiment was conducted. In the experiment, the proposed models were compared. They were based on a data-driven method with two baselines: (1) a simple statistical model based on behavior frequency and (2) raw experimental data. The evaluation was based on the observation of video clips, in which one of the subjects was replaced by a robot performing head movements in the above-mentioned three conditions. The experimental results showed that there was no significant difference from original human behaviors in the data corpus and proved the effectiveness of the proposed models.
Correction: Sartorius et al. “Postprandial Effects of a Proprietary Milk Protein Hydrolysate Containing Bioactive Peptides in Prediabetic Subjects” Nutrients 2019, 11, 1700
Authors: Sartorius Tina , Weidner Andrea , Dharsono Tanita , Boulier Audrey , Wilhelm Manfred , Schön Christiane
Published: April 2020

Milk proteins have been hypothesized to protect against type 2 diabetes (T2DM) by beneficially modulating glycemic response, predominantly in the postprandial status. This potential is, amongst others, attributed to the high content of whey proteins, which are commonly a product of cheese production. However, native whey has received substantial attention due to its higher leucine content, and its postprandial glycemic effect has not been assessed thus far in prediabetes. In the present study, the impact of a milk protein hydrolysate of native whey origin with alpha-glucosidase inhibiting properties was determined in prediabetics in a randomized, cross-over trial. Subjects received a single dose of placebo or low- or high-dosed milk protein hydrolysate prior to a challenge meal high in carbohydrates. Concentration–time curves of glucose and insulin were assessed. Incremental areas under the curve (iAUC) of glucose as the primary outcome were significantly reduced by low-dosed milk peptides compared to placebo (p = 0.0472), and a minor insulinotropic effect was seen. A longer intervention period with the low-dosed product did not strengthen glucose response but significantly reduced HbA1c values (p = 0.0244). In conclusion, the current milk protein hydrolysate of native whey origin has the potential to modulate postprandial hyperglycemia and hence may contribute in reducing the future risk of developing T2DM.
Non-Destructive Measurement of Three-Dimensional Plants Based on Point Cloud
Authors: Wang Yawei , Chen Yifei
Published: April 2020

In agriculture, information about the spatial distribution of plant growth is valuable for applications. Quantitative study of the characteristics of plants plays an important role in the plants’ growth and development research, and non-destructive measurement of the height of plants based on machine vision technology is one of the difficulties. We propose a methodology for three-dimensional reconstruction under growing plants by Kinect v2.0 and explored the measure growth parameters based on three-dimensional (3D) point cloud in this paper. The strategy includes three steps—firstly, preprocessing 3D point cloud data, completing the 3D plant registration through point cloud outlier filtering and surface smooth method; secondly, using the locally convex connected patches method to segment the leaves and stem from the plant model; extracting the feature boundary points from the leaf point cloud, and using the contour extraction algorithm to get the feature boundary lines; finally, calculating the length, width of the leaf by Euclidean distance, and the area of the leaf by surface integral method, measuring the height of plant using the vertical distance technology. The results show that the automatic extraction scheme of plant information is effective and the measurement accuracy meets the need of measurement standard. The established 3D plant model is the key to study the whole plant information, which reduces the inaccuracy of occlusion to the description of leaf shape and conducive to the study of the real plant growth status.