bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients Admitted for Variant Alpha COVID-19 Have Poorer Outcomes than Those Infected with the Old Strain
Authors: Vassallo Matteo , Manni Sabrina , Klotz Camille , Fabre Roxane , Pini Paola , Blanchouin Elea , Sindt Audrey , Lotte Laurene , Dubertrand Jean Marc , Liguori Stephane , Berkane Nathalie , Duval Yannick , Rolland Fabien , Pradier Christian
Published: August 2021

Objectives: The variant alpha COVID-19 rapidly spread across Europe in early 2021. While this variant’s increased infectivity has been proven, little is known of its clinical presentation and outcomes compared to the old strain. Methods: We identified patients admitted to the Cannes General Hospital for variant alpha-related COVID-19 infection from January to April 2021. Their main demographic parameters, inflammatory markers and clinical characteristics were recorded. Patients admitted from October to December 2020 for 20E (EU1) COVID-19 were selected as controls. Differences between groups were analyzed. Results: We included 157 patients (mean age 73 years; 58% men; mean delay of symptoms 6.9 days). Comorbidities were present in 92% (mainly hypertension, diabetes and obesity or overweight). The prevalence of comorbidities did not differ between groups. In 28% of cases, patients either died or required transfer to the Intensive Care Unit (ICU). The cause of death or of transfer to the ICU was presumably associated with severe pneumonia. Variant alpha COVID-19 had 3.8-fold higher risk of death or transfer to the ICU compared to the old strain. Discussion: Patients infected with variant alpha COVID-19, despite similar background characteristics, had a higher risk of unfavorable outcomes than those infected with the old strain, suggesting increased virulence related to this variant.
Effect of COVID-19 Lockdown in Spain on Structural and Functional Outcomes of Neovascular AMD Patients
Authors: Valverde-Megías Alicia , Rego-Lorca Daniela , Fernández-Vigo José Ignacio , Murciano-Cespedosa Antonio , Megías-Fresno Alicia , García-Feijoo Julián
Published: August 2021

This is a retrospective single-center study of patients with neovascular age-related macular degeneration whose follow-up was delayed due to COVID-19 pandemic with at least three months between visits in Madrid, Spain. The purpose of the study was to evaluate best corrected visual acuity (BCVA) changes and try to identify features in optical coherence tomography (OCT) that could be related to more profound visual loss. It included 270 eyes. The two last visits before lockdown were used for comparison with the visit after lockdown. BCVA changed from 60.2 ± 18.2 to 55.9 ± 20.5 ETDRS letters. 29% of the eyes lost more than 5 letters. OCT was active in 67% of eyes before lockdown and in 80.4% after lockdown. Multiple lineal analysis showed that patients whose OCT before lockdown presented with a combination of intra and subretinal fluid were more likely to suffer a greater visual loss (p = 0.002). These patients should be encouraged to not miss any visits in case a new lockdown is imposed.
Effects of Global Warming on the Poleward Heat Transport by Non-Stationary Large-Scale Atmospheric Eddies, and Feedbacks Affecting the Formation of the Arctic Climate
Authors: Soldatenko Sergei
Published: August 2021

It is a well-known fact that the observed rise in the Arctic near-surface temperature is more than double the increase in global mean temperature. However, the entire scientific picture of the formation of the Arctic amplification has not yet taken final shape and the causes of this phenomenon are still being discussed within the scientific community. Some recent studies suggest that the atmospheric equator-to-pole transport of heat and moisture, and also radiative feedbacks, are among the possible reasons for the Arctic amplification. In this paper, we highlight and summarize some of our research related to assessing the response of climate in the Arctic to global warming and vice versa. Since extratropical transient eddies dominate the meridional transport of sensible and latent heat from low to high latitudes, we estimated the effect of climate change on meridional heat transport by means of the β-plane model of baroclinic instability. It has been shown that the heat transport from low and middle latitudes to the Arctic by large scale transient eddies increases by about 9% due to global warming, contributing to the polar amplification and thereby a decrease in the extent of the Arctic sea, which, in turn, is an important factor in the formation of the Arctic climate. The main radiative feedback mechanisms affecting the formation of the Arctic climate are also considered and discussed. It was emphasized that the influence of feedbacks depends on a season since the total feedback in the winter season is negative, while in the summer season, it is positive. Thus, further research is required to diminish the uncertainty regarding the character of various feedback mechanisms in the shaping of the Artic climate and, through that, in predicting the extent of Arctic sea ice.
A New Low-Cost Acoustic Beamforming Architecture for Real-Time Marine Sensing: Evaluation and Design
Authors: Nsalo Kong Darryl Franck , Shen Chong , Tian Chuan , Zhang Kun
Published: August 2021

This paper mainly studies the performance of an acoustic beamforming technique applied to a low-cost hydrophone in a linear array of two to four elements for the detection and localization of underwater acoustic sound waves. It also evaluates the integration of the array in an energy-efficient real-time monitoring system architecture, allowing marine sensing to be conducted without human intervention. Such architecture would consist of vertical linear arrays of two or four RHSA-10 hydrophones models attached to a buoy or a vessel for sound detection; a frequency domain beamformer (FDB) technique implemented in a Xilinx Spartan-7 field programmable gate array (FPGA) for sound source localization; a LoRa wireless sensor network mote to provide convenient access from a base center. The architecture aims to alleviate sea traffic control for countries that lack the financial resources to properly address illegal fishing or piracy issues, mostly committed in small fast motorized boats. In our experiment, the sound waves emitted by a small motorized boat were successfully detected and tracked by three data acquisitions at a 1 km range. It is demonstrated that a system using a small number of hydrophones is capable of producing robust accuracy over a large band frequency in the presence of noise interference.
Automatic Meningioma Segmentation and Grading Prediction: A Hybrid Deep-Learning Method
Authors: Chen Chaoyue , Cheng Yisong , Xu Jianfeng , Zhang Ting , Shu Xin , Huang Wei , Hua Yu , Zhang Yang , Teng Yuen , Zhang Lei , Xu Jianguo
Published: August 2021

The purpose of this study was to determine whether a deep-learning-based assessment system could facilitate preoperative grading of meningioma. This was a retrospective study conducted at two institutions covering 643 patients. The system, designed with a cascade network structure, was developed using deep-learning technology for automatic tumor detection, visual assessment, and grading prediction. Specifically, a modified U-Net convolutional neural network was first established to segment tumor images. Subsequently, the segmentations were introduced into rendering algorithms for spatial reconstruction and another DenseNet convolutional neural network for grading prediction. The trained models were integrated as a system, and the robustness was tested based on its performance on an external dataset from the second institution involving different magnetic resonance imaging platforms. The results showed that the segment model represented a noteworthy performance with dice coefficients of 0.920 ± 0.009 in the validation group. With accurate segmented tumor images, the rendering model delicately reconstructed the tumor body and clearly displayed the important intracranial vessels. The DenseNet model also achieved high accuracy with an area under the curve of 0.918 ± 0.006 and accuracy of 0.901 ± 0.039 when classifying tumors into low-grade and high-grade meningiomas. Moreover, the system exhibited good performance on the external validation dataset.
Personalized and Self-Management: Systematic Search and Evaluation Quality Factors and User Preference of Drug Reference Apps in Taiwan
Authors: Chen Yu-Chun , Liao Wei-Wei , Su Mei-Chin , Lin Yen-Hsi
Published: August 2021

Background: Drug reference apps promote self-management and improve the efficiency and quality of work for physicians, nurses, pharmacists, and patients. This study aimed to describe a systematic and stepwise process to identify drug reference apps in Taiwan, assess the quality of these apps, and analyze the influential factors for user ratings. Methods: A two-step algorithm (KESS) consisting of keyword growing and systematic search was proposed. Seven independent reviewers were trained to evaluate these apps using Mobile App Rating Scale (MARS). A logistic regression model was fitted and average marginal effects (AME) were calculated to identify the effects of factors for higher user ratings. Results: A total of 23 drug reference apps in Taiwan were identified and analyzed. Generally, these drug reference apps were evaluated as acceptable quality with an average MARS score of 3.23. Higher user engagement, more functionality, better aesthetics, and more information associated with higher user ratings. Navigation is the most influential factor on higher user ratings (AME: 13.15%) followed by performance (AME: 11.03%), visual appeal (AME: 10.87%), credibility (AME: 10.67%), and quantity of information (AME: 10.42%). Conclusions: User experience and information clearly affect user ratings of drug reference apps. Five key factors should be considered when designing drug reference apps.
The Differentiation in Cultivated Land Quality between Modern Agricultural Areas and Traditional Agricultural Areas: Evidence from Northeast China
Authors: Li Quanfeng , Guo Wenhao , Sun Xiaobing , Yang Aizheng , Qu Shijin , Chi Wenfeng
Published: August 2021

Many studies of cultivated land use have focused on evaluating land quality. However, these studies rarely compare cultivated land quality (CLQ) between modern agricultural areas (MA) and traditional agricultural areas (TA). Thus, policymakers sometimes experience difficulties utilizing existing CLQ theories in CLQ improvement, especially in developing countries experiencing the transformation from traditional to modern agriculture. The objective of this study was to build a comprehensive hierarchical framework to compare the CLQ in MA and TA from the multidimensional perspectives of fertility, project, landscape, and ecology. An empirical analysis was conducted in Fujin City, Heilongjiang Province, Northeast China. The results showed that comprehensive CLQ in MA is better than that in TA, but individual cultivated land quality results are not the same as comprehensive quality. Specifically, project, landscape, and ecology quality in MA are better than in TA. However, fertility quality in MA is still worse. Moreover, the CLQ in MA tends to be more consistent in a small range, while the spatial pattern of CLQ in TA is disordered. We then argue that these results should be associated with different management modes and agrarian property systems between MA and TA. Based on our findings, four suggestions were generated to improve CLQ. Overall, this study provides a new comprehensive insight for understanding CLQ, and the framework, method, and findings of this study can help increase the effectiveness of CLQ improvements.
Sol–Gel Synthesis and Characterization of a Quaternary Bioglass for Bone Regeneration and Tissue Engineering
Authors: Bento Ricardo , Gaddam Anuraag , Ferreira José M. F.
Published: August 2021

Sol–gel synthesis using inorganic and/or organic precursors that undergo hydrolysis and condensation at room temperature is a very attractive and less energetic method for preparing bioactive glass (BG) compositions, as an alternative to the melt-quenching process. When properly conducted, sol–gel synthesis might result in amorphous structures, with all of the components intimately mixed at the atomic scale. Moreover, developing new and better performing materials for bone tissue engineering is a growing concern, as the aging of the world’s population leads to lower bone density and osteoporosis. This work describes the sol–gel synthesis of a novel quaternary silicate-based BG with the composition 60 SiO2–34 CaO–4 MgO–2 P2O5 (mol%), which was prepared using acidified distilled water as a single solvent. By controlling the kinetics of the hydrolysis and condensation steps, an amorphous glass structure could be obtained. The XRD results of samples calcined within the temperature range of 600–900 °C demonstrated that the amorphous nature was maintained until 800 °C, followed by partial crystallization at 900 °C. The specific surface area—an important factor in osteoconduction—was also evaluated over different temperatures, ranging from 160.6 ± 0.8 m2/g at 600 °C to 2.2 ± 0.1 m2/g at 900 °C, accompanied by consistent changes in average pore size and pore size distribution. The immersion of the BG particles in simulated body fluid (SBF) led to the formation of an extensive apatite layer on its surface. These overall results indicate that the proposed material is very promising for biomedical applications in bone regeneration and tissue engineering.
Ionic Liquids and Deep Eutectic Solvents for CO2 Conversion Technologies—A Review
Authors: Maniam Kranthi Kumar , Paul Shiladitya
Published: August 2021

Ionic liquids (ILs) have a wide range of potential uses in renewable energy, including CO2 capture and electrochemical conversion. With the goal of providing a critical overview of the progression, new challenges, and prospects of ILs for evolving green renewable energy processes, this review emphasizes the significance of ILs as electrolytes and reaction media in two primary areas of interest: CO2 electroreduction and organic molecule electrosynthesis via CO2 transformation. Herein, we briefly summarize the most recent advances in the field, as well as approaches based on the electrochemical conversion of CO2 to industrially important compounds employing ILs as an electrolyte and/or reaction media. In addition, the review also discusses the advances made possible by deep eutectic solvents (DESs) in CO2 electroreduction to CO. Finally, the critical techno-commercial issues connected with employing ILs and DESs as an electrolyte or ILs as reaction media are reviewed, along with a future perspective on the path to rapid industrialization.
Catalytic Abatement of Volatile Organic Compounds and Soot over Manganese Oxide Catalysts
Authors: Figueredo Miguel Jose Marin , Cocuzza Clarissa , Bensaid Samir , Fino Debora , Piumetti Marco , Russo Nunzio
Published: August 2021

A set of manganese oxide catalysts was synthesized via two preparation techniques: solution combustion synthesis (Mn3O4/Mn2O3-SCS and Mn2O3-SCS) and sol-gel synthesis (Mn2O3-SG550 and Mn2O3-SG650). The physicochemical properties of the catalysts were studied by means of N2-physisorption at −196 °C, X-ray powder diffraction, H2 temperature-programmed reduction (H2-TPR), soot-TPR, X-ray photoelectron spectroscopy (XPS) and field-emission scanning electron microscopy (FESEM). The high catalytic performance of the catalysts was verified in the oxidation of Volatile Organic Compounds (VOC) probe molecules (ethene and propene) and carbon soot in a temperature-programmed oxidation setup. The best catalytic performances in soot abatement were observed for the Mn2O3-SG550 and the Mn3O4/Mn2O3-SCS catalysts. The catalytic activity in VOC total oxidation was effectively correlated to the enhanced low-temperature reducibility of the catalysts and the abundant surface Oα-species. Likewise, low-temperature oxidation of soot in tight contact occurred over the Mn2O3-SG550 catalyst and was attributed to high amounts of surface Oα-species and better surface reducibility. For the soot oxidation in loose contact, the improved catalytic performance of the Mn3O4/Mn2O3-SCS catalyst was attributed to the beneficial effects of both the morphological structure that—like a filter—enhanced the capture of soot particles and to a probable high amount of surface acid-sites, which is characteristic of Mn3O4 catalysts.
ToF-SIMS Analysis of Demineralized Dentin Biomodified with Calcium Phosphate and Collagen Crosslinking: Effect on Marginal Adaptation of Class V Adhesive Restorations
Authors: Betancourt Francisco , Kiss Andràs , Krejci Ivo , Bortolotto Tissiana
Published: August 2021

This study aimed to assess the effect of biomodification before adhesive procedures on the tooth-restoration interface of class V restorations located in caries-simulated vs. sound dentin, and the quality of dentin surface by time-of-flight secondary ion mass spectrometry (ToF-SIMS). Class V cavities located on cervical dentin were prepared on the buccal surfaces of extracted human molars under the simulation of intratubular fluid flow. Two dentin types, i.e., sound and demineralized by formic-acid, were biomodified with 1% riboflavin and calcium phosphate (CaP) prior to the application of a universal adhesive (Clearfil Universal Bond) in etch and rinse or self-etch mode, and a conventional micro hybrid composite (Clearfil APX). Restorations were subjected to thermo mechanical fatigue test and percentages of continuous margins (% CM) before/after fatigue were compared. Bio modification of dentin surfaces at the molecular level was analyzed by Time-of-Flight Secondary Mass Spectometry (ToF-SIMS). % CM were still significantly higher in tooth-restoration interfaces on sound dentin. Meanwhile, biomodification with riboflavin and CaP had no detrimental effect on adhesion and in carious dentin, it improved the % CM both before and after loading. Etching carious dentin with phosphoric acid provided with the lowest results, leading even to restoration loss. The presence of molecule fragments of riboflavin and CaP were detected by ToF-SIMS, evidencing dentin biomodification. The adhesive interface involving carious dentin could be improved by the use of a collagen crosslinker and CaP prior to adhesive procedures.
Steric Effects on Space Electroosmotic Thrusters in Soft Nanochannels
Authors: Zheng Jiaxuan , Jia Beinan , Jian Yongjun
Published: August 2021

The influence of steric effects on the performances of space electroosmotic thrusters (EOTs) was numerically delineated in soft nanochannels for which its walls are covered with polyelectrolyte materials. The size effect of the ionic species, namely the steric effect, is neglected in many previous research studies, but it has vital influences on electrostatic potential and electroosmotic velocity, which is further introduced into the present study in order to understand and improve the exploration of nano electroosmotic thrusters with soft channels. The thruster’s thrust, specific impulse, total input power, thruster efficiency and thrust-to-power ratio are computed based on finite difference methods. It is found that the thruster’s thrust and specific impulse increase with the steric parameter while the efficiency and thrust-to-power ratio possess opposite trends due to the enhancement of Joule heating dissipation. For real situations with the consideration of ion size, although the thruster’s thrust could be promoted, the efficiency is only 30–70%, and the peak values of thrust-to-power ratio fade away.
A Two Phase Integrated Fuzzy Decision-Making Framework for Green Supplier Selection in the Coffee Bean Supply Chain
Authors: Nguyen Ngoc Bao Tu , Lin Gu-Hong , Dang Thanh-Tuan
Published: August 2021

In Vietnam, as more and more organizations are moving toward globalization, green supplier selection (GSS) has emerged as a strategic approach in supply chain management that requires supplier practices in lessening the environmental risks to society. Based on both conventional and environmental criteria, this paper aims to evaluate a set of suppliers by establishing a multi-criteria decision-making (MCDM)-based framework using an integrated fuzzy analytical hierarchy process (FAHP) with the VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method. Initially, five GSS criteria of the environmental aspect (wastewater treatment, solid waste generation, energy consumption, air pollution, corporate social responsibility) and conventional criteria (quality, cost, delivery, and technology) are identified from the literature and consulting field experts to employ the MCDM approach. The trustworthiness of the proposed integrated framework is presented by discussing a case study in the coffee bean supply chain in Vietnam. The FAHP is used to generate criteria weights in which fuzzy set theory is applied to translate the linguistic evaluation statements of experts, and VIKOR is used to rank the alternatives against the selected criteria. From FAHP findings, the most important criteria are quantity discount, solid waste generation, order fulfillment rate, logistics cost, and purchasing cost. A consistency test is performed to ensure the uniformity of the expert’s input. The best suppliers are determined through the final ranking of the VIKOR model for the case study. The work presented provides insight to decision-makers of supplier selection that helps determine significant GSS criteria and aids in the minimization of environmental risks to society arising from the supply chain on corporate sustainability standards.
Liver Transplantation Is Highly Effective in Children with Irresectable Hepatoblastoma
Authors: Moosburner Simon , Schmelzle Moritz , Schöning Wenzel , Kästner Anika , Seika Philippa , Globke Brigitta , Dziodzio Tomasz , Pratschke Johann , Öllinger Robert , Gül-Klein Safak
Published: August 2021

Background and Objectives: In children, hepatoblastoma preferentially is managed by liver resection (LR). However, in irresectable cases, liver transplantation (LT) is required. The aim of our study was to compare short- and long-term results after LR and LT for the curative treatment of hepatoblastoma. Materials and Methods: Retrospective analysis of all patients treated surgically for hepatoblastoma from January 2000 until December 2019 was performed. Demographic and clinical data were collected before and after surgery. The primary endpoints were disease free survival and patient survival. Results: In total, 38 patients were included into our analysis (n = 28 for LR, n = 10 for LT) with a median follow-up of 5 years. 36 patients received chemotherapy prior to surgery. Total hospital stay and intensive care unit (ICU) stay were significantly longer within the LT vs. the LR group (ICU 23 vs. 4 days, hospital stay 34 vs. 16 days, respectively; p < 0.001). Surgical complications (≤Clavien–Dindo 3a) were equally distributed in both groups (60% vs. 57%; p = 1.00). Severe complications (≥Clavien–Dindo 3a) were more frequent after LT (50% vs. 21.4%; p = 0.11). Recurrence rates were 10.7% for LR and 0% for LT at 5 years after resection or transplantation (p = 0.94). Overall, 5-year survival was 90% for LT and 96% for LR (p = 0.44). Conclusions: In irresectable cases, liver transplantation reveals excellent outcomes in children with hepatoblastoma with an acceptable number of perioperative complications.
Towards User-Oriented Recommendations for Local Therapy of Leg and Foot Ulcers—An Update of a S3-German Guideline
Authors: Burckhardt Marion , Nink-Grebe Brigitte , Maier-Hasselmann Andreas
Published: August 2021

Background: The German S3- guideline on local therapy of leg ulcers and diabetic foot ulcers is in the process of being updated. Major goals are to improve the guidelines’ applicability and to take steps towards a living guideline according to current methodological standards. The aim of this article is to describe the main measures to achieve these goals. Methods: The context of the guideline in the field of local wound care and the stakeholder requirements are briefly described. Based on a derived framework, the project team adjusted the methods for the guideline. Results: Main adjustments are more specific inclusion criteria, online consensus meetings and the use of an authoring and publication platform to provide information in a multi-layered format. A new set of practice-oriented key questions were defined by the guideline panel to foster the formulation of action-oriented recommendations. Conclusions: The set of new key questions addressing practical problems and patients’ preferences as well as the adjustments made to improve not only the guidelines’ applicability, but also the feasibility of the further dynamic updating processes in the sense of a living guideline, should be steps in the right direction.
Viral Enteritis in Cattle: To Well Known Viruses and Beyond
Authors: Castells Matías , Colina Rodney
Published: August 2021

Livestock products supply about 13 percent of energy and 28 percent of protein in diets consumed worldwide. Diarrhea is a leading cause of sickness and death of beef and dairy calves in their first month of life and also affecting adult cattle, resulting in large economic losses and a negative impact on animal welfare. Despite the usual multifactorial origin, viruses are generally involved, being among the most important causes of diarrhea. There are several viruses that have been confirmed as etiological agents (i.e., rotavirus and coronavirus), and some viruses that are not yet confirmed as etiological agents. This review summarizes the viruses that have been detected in the enteric tract of cattle and tries to deepen and gather knowledge about them.
Characterizing the Shearing Stresses within the CDC Biofilm Reactor Using Computational Fluid Dynamics
Authors: Johnson Erick , Petersen Theodore , Goeres Darla M.
Published: August 2021

Shearing stresses are known to be a critical factor impacting the growth and physiology of biofilms, but the underlying fluid dynamics within biofilm reactors are rarely well characterized and not always considered when a researcher decides which biofilm reactor to use. The CDC biofilm reactor is referenced in validated Standard Test Methods and US EPA guidance documents. The driving fluid dynamics within the CDC biofilm reactor were investigated using computational fluid dynamics. An unsteady, three-dimensional model of the CDC reactor was simulated at a rotation rate of 125 RPM. The reactor showed turbulent structures, with shear stresses averaging near 0.365 ± 0.074 Pa across all 24 coupons. The pressure variation on the coupon surfaces was found to be larger, with a continuous 2–3 Pa amplitude, coinciding with the baffle passage. Computational fluid dynamics was shown to be a powerful tool for defining key fluid dynamic parameters at a high fidelity within the CDC biofilm reactor. The consistency of the shear stresses and pressures and the unsteadiness of the flow within the CDC reactor may help explain its reproducibility in laboratory studies. The computational model will enable researchers to make an informed decision whether the fluid dynamics present in the CDC biofilm reactor are appropriate for their research.
Microbial Shift in the Enteric Bacteriome of Coral Reef Fish Following Climate-Driven Regime Shifts
Authors: Cheutin Marie-Charlotte , Villéger Sébastien , Hicks Christina C. , Robinson James P. W. , Graham Nicholas A. J. , Marconnet Clémence , Restrepo Claudia Ximena Ortiz , Bettarel Yvan , Bouvier Thierry , Auguet Jean-Christophe
Published: August 2021

Replacement of coral by macroalgae in post-disturbance reefs, also called a “coral-macroalgal regime shift”, is increasing in response to climate-driven ocean warming. Such ecosystem change is known to impact planktonic and benthic reef microbial communities but few studies have examined the effect on animal microbiota. In order to understand the consequence of coral-macroalgal shifts on the coral reef fish enteric bacteriome, we used a metabarcoding approach to examine the gut bacteriomes of 99 individual fish representing 36 species collected on reefs of the Inner Seychelles islands that, following bleaching, had either recovered to coral domination, or shifted to macroalgae. While the coral-macroalgal shift did not influence the diversity, richness or variability of fish gut bacteriomes, we observed a significant effect on the composition (R2 = 0.02; p = 0.001), especially in herbivorous fishes (R2 = 0.07; p = 0.001). This change is accompanied by a significant increase in the proportion of fermentative bacteria (Rikenella, Akkermensia, Desulfovibrio, Brachyspira) and associated metabolisms (carbohydrates metabolism, DNA replication, and nitrogen metabolism) in relation to the strong turnover of Scarinae and Siganidae fishes. Predominance of fermentative metabolisms in fish found on macroalgal dominated reefs indicates that regime shifts not only affect the taxonomic composition of fish bacteriomes, but also have the potential to affect ecosystem functioning through microbial functions.
Seroprevalence of Cysticercosis among Epileptic Patients Attending Neurological Units in the Urban Area of Abidjan
Authors: Soumahoro Man-Koumba , Melki Jihen , Assi Berthe , Kangah Yves Landry , Camara Mamadou , Tazemda-Kuitsouc Gildas Boris , Nowakowski Mireille , Yapo-Ehounoud Constance , Sonan Thérèse , Bellalou Jacques , Jambou Ronan
Published: August 2021

Cysticercosis is one of the main causes of secondary epilepsy in sub-Saharan Africa. To estimate the seroprevalence of cysticercosis among epileptic patients, we conducted a cross-sectional study of patients attending neurology consultation in Abidjan, Côte d’Ivoire. Methods: Patients’ socio-demographic and lifestyle data were collected as well as blood samples for serological testing using ELISA and Western blot based on IgG antibodies detection. For qualitative variables comparison, Chi2 or Fisher tests were used; a Student’s t-test was used to compare quantitative variables. A multivariate logistic regression model was fit to identify risks factors. Results: Among 403 epileptic patients included in the study, 55.3% were male; the median age was 16.9 years; 77% lived in Abidjan; 26.5% were workers. Most patients included in the study had tonic-clonic seizures (80%), and 11.2% had focal deficit signs. The seroprevalence of cysticercosis was 6.0%. The risk was higher in patients over 30 years old (aOR = 5.1 (1.3–20.0)) than in patients under 16. The risk was also considerably high in patients who reported epileptics in the family (aOR = 5 (1.7–14.6)). The risk was three-fold less in females than in males. Conclusions: This study highlighted the exposure of epileptic patients to Taenia solium larvae in an urban area. The risk of positive serology was increased with age, male gender, and family history of epilepsy.
Potential Anti-Alzheimer Agents from Guanidinyl Tryptophan Derivatives with Activities of Membrane Adhesion and Conformational Transition Inhibitions
Authors: Wongrattanakamon Pathomwat , Jiaranaikulwanitch Jutamas , Vajragupta Opa , Jiranusornkul Supat , Saenjum Chalermpong , Yooin Wipawadee
Published: August 2021

Guanidinyl tryptophan derivatives TGN1, TGN2, TGN3, and TGN4 were synthesized, and these compounds were shown to possess in vitro inhibitory activity for amyloid aggregation in a previous study. Nevertheless, the influence of the TGN series of compounds on the binding and permeation behaviors of an Aβ monomer to the cell membranes was not elucidated. In this study, we investigated the effect of compounds in the TGN series on the behavior of an Aβ monomer regarding its toxicity toward the bilayer lipid membrane using molecular dynamics (MD) simulation. MD simulations suggest that TGN4 is a potential agent that can interfere with the movement of the Aβ monomer into the membrane. The MM-GBSA result demonstrated that TGN4 exhibits the highest affinity to the Aβ1–42 monomer but has the lowest affinity to the bilayer. Moreover, TGN4 also contributes to a decrease in the binding affinity between the Aβ1–42 monomer and the POPC membrane. Regarding the results of the binding mode and conformational analyses, a high number of amino-acid residues were shown to provide the binding interactions between TGN4 and the Aβ1–42 monomer. TGN4 also reduces the conformational transition of the Aβ1–42 monomer by means of interacting with the monomer. The present study presents molecular-level insights into how the TGN series of compounds affect the membrane adsorption and the conformational transition of the Aβ1–42 monomer, which could be valuable for the further development of new anti-Alzheimer agents.
A Concise Review of Current In Vitro Chemical and Cell-Based Antioxidant Assay Methods
Authors: Nwachukwu Ifeanyi D. , Sarteshnizi Roghayeh Amini , Udenigwe Chibuike C. , Aluko Rotimi E.
Published: August 2021

Antioxidants remain interesting molecules of choice for suppression of the toxic effects of free radicals in foods and human systems. The current practice involves the use of mainly synthetic molecules as potent antioxidant agents. However, due to the potential negative impact on human health, there is an intensive effort within the research community to develop natural alternatives with similar antioxidant efficacy but without the negative side effects of synthetic molecules. Still, the successful development of new molecules depends on the use of reliable chemical or cell culture assays to screen antioxidant properties. Chemical antioxidant assays include the determination of scavenging ability against free radicals such as DPPH, superoxide anion radicals, hydroxyl radicals, hydrogen peroxide, and nitric oxide. Other antioxidant tests include the ability of compounds to bind and sequester prooxidant metal cations, reduce ferric iron, and attenuate the rate of lipid oxidation. Ex vivo tests utilize cell cultures to confirm entry of the molecules into cells and the ability to quench synthetic intracellular free radicals or to stimulate the increased biosynthesis of endogenous antioxidants. In order to assist researchers in their choice of antioxidant evaluation methods, this review presents background scientific information on some of the most commonly used antioxidant assays with a comparative discussion of the relevance of published literature data to food science and human nutrition applications.
Beneficial Effect of Quercetin on Erythrocyte Properties in Type 2 Diabetic Rats
Authors: Jasenovec Tomas , Radosinska Dominika , Kollarova Marta , Balis Peter , Ferenczyova Kristina , Kalocayova Barbora , Bartekova Monika , Tothova Lubomira , Radosinska Jana
Published: August 2021

Diabetes mellitus is characterized by tissue oxidative damage and impaired microcirculation, as well as worsened erythrocyte properties. Measurements of erythrocyte deformability together with determination of nitric oxide (NO) production and osmotic resistance were used for the characterization of erythrocyte functionality in lean (control) and obese Zucker diabetic fatty (ZDF) rats of two age categories. Obese ZDF rats correspond to prediabetic (younger) and diabetic (older) animals. As antioxidants were suggested to protect erythrocytes, we also investigated the potential effect of quercetin (20 mg/kg/day for 6 weeks). Erythrocyte deformability was determined by the filtration method and NO production using DAF-2DA fluorescence. For erythrocyte osmotic resistance, we used hemolytic assay. Erythrocyte deformability and NO production deteriorated during aging—both were lower in older ZDF rats than in younger ones. Three-way ANOVA indicates improved erythrocyte deformability after quercetin treatment in older obese ZDF rats only, as it was not modified or deteriorated in both (lean and obese) younger and older lean animals. NO production by erythrocytes increased post treatment in all experimental groups. Our study indicates the potential benefit of quercetin treatment on erythrocyte properties in condition of diabetes mellitus. In addition, our results suggest potential age-dependency of quercetin effects in diabetes that deserve additional research.
Solvatomorphism of Moxidectin
Authors: Grell Toni , Barbero Mauro , Pattarino Franco , Giovenzana Giovanni Battista , Colombo Valentina
Published: August 2021

The solvatomorphism of the anthelmintic drug moxidectin is investigated, and a new solvatomorph with nitromethane is reported. Moreover, the hitherto unknown crystal structures of the solvatomorphs with ethanol and 2-propanol are reported and discussed. The thermal characterization of these solvatomorphs through variable-temperature powder X-ray diffraction analysis (VT-PXRD) is also described, providing new insights into the crystallochemistry of this active pharmaceutical ingredient.
Abietane Diterpenoids Isolated from Clerodendrum bracteatum and Their Antioxidant and Cytotoxic Activities
Authors: Li Pingting , Li Lingling , Zhu Qin , Xu Mingfeng
Published: August 2021

Two new abietane diterpenoids (1,2), along with five known diterpenoids (3–7), were first isolated and purified from the stems of Clerodendrum bracteatum. The structures of the new compounds were established by extensive analysis of mass spectrometric and 1-D, 2-D NMR spectroscopic data. Their antioxidant activities were determined on DPPH radical scavenging and ABTS. The in vitro cytotoxic activities of the compounds were evaluated against the HL-60 and A549 cell lines by the MTT method.
Rhodococcus as Biofactories for Microbial Oil Production
Authors: Alvarez Héctor M. , Hernández Martín A. , Lanfranconi Mariana P. , Silva Roxana A. , Villalba María S.
Published: August 2021

Bacteria belonging to the Rhodococcus genus are frequent components of microbial communities in diverse natural environments. Some rhodococcal species exhibit the outstanding ability to produce significant amounts of triacylglycerols (TAG) (>20% of cellular dry weight) in the presence of an excess of the carbon source and limitation of the nitrogen source. For this reason, they can be considered as oleaginous microorganisms. As occurs as well in eukaryotic single-cell oil (SCO) producers, these bacteria possess specific physiological properties and molecular mechanisms that differentiate them from other microorganisms unable to synthesize TAG. In this review, we summarized several of the well-characterized molecular mechanisms that enable oleaginous rhodococci to produce significant amounts of SCO. Furthermore, we highlighted the ability of these microorganisms to degrade a wide range of carbon sources coupled to lipogenesis. The qualitative and quantitative oil production by rhodococci from diverse industrial wastes has also been included. Finally, we summarized the genetic and metabolic approaches applied to oleaginous rhodococci to improve SCO production. This review provides a comprehensive and integrating vision on the potential of oleaginous rhodococci to be considered as microbial biofactories for microbial oil production.
Pyridine Scaffolds, Phenols and Derivatives of Azo Moiety: Current Therapeutic Perspectives
Authors: Tahir Tehreem , Ashfaq Muhammad , Saleem Muhammad , Rafiq Muhammad , Shahzad Mirza Imran , Kotwica-Mojzych Katarzyna , Mojzych Mariusz
Published: August 2021

Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure–activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.
1,2,5-Thiadiazole 1,1-dioxides and Their Radical Anions: Structure, Properties, Reactivity, and Potential Use in the Construction of Functional Molecular Materials
Authors: Pakulski Paweł , Pinkowicz Dawid
Published: August 2021

This work provides a summary of the preparation, structure, reactivity, physicochemical properties, and main uses of 1,2,5-thiadiazole 1,1-dioxides in chemistry and material sciences. An overview of all currently known structures containing the 1,2,5-thiadiazole 1,1-dioxide motif (including the anions radical species) is provided according to the Cambridge Structural Database search. The analysis of the bond lengths typical for neutral and anion radical species is performed, providing a useful tool for unambiguous assessment of the valence state of the dioxothiadiazole-based compounds based solely on the structural data. Theoretical methodologies used in the literature to describe the dioxothiadiazoles are also shortly discussed, together with the typical ‘fingerprint’ of the dioxothiadiazole ring reported by means of various spectroscopic techniques (NMR, IR, UV-Vis). The second part describes the synthetic strategies leading to 1,2,5-thiadiazole 1,1-dioxides followed by the discussion of their electrochemistry and reactivity including mainly the chemical methods for the successful reduction of dioxothiadiazoles to their anion radical forms and the ability to form coordination compounds. Finally, the magnetic properties of dioxothiadiazole radical anions and the metal complexes involving dioxothiadiazoles as ligands are discussed, including simple alkali metal salts and d-block coordination compounds. The last section is a prospect of other uses of dioxothiadiazole-containing molecules reported in the literature followed by the perspectives and possible future research directions involving these compounds.
The Role of Allium subhirsutum L. in the Attenuation of Dermal Wounds by Modulating Oxidative Stress and Inflammation in Wistar Albino Rats
Authors: Saoudi Mongi , Badraoui Riadh , Chira Ahlem , Saeed Mohd , Bouali Nouha , Elkahoui Salem , Alam Jahoor M. , Kallel Choumous , El Feki Abdelfattah
Published: August 2021

In our study, Allium subhirsutum L. (AS) was investigated to assess its phenolic profile and bioactive molecules including flavonoids and organosulfur compounds. The antioxidant potential of AS and wound healing activity were addressed using skin wound healing and oxidative stress and inflammation marker estimation in rat models. Phytochemical and antiradical activities of AS extract (ASE) and oil (ASO) were studied. The rats were randomly assigned to four groups: group I served as a control and was treated with simple ointment base, group II was treated with ASE ointment, group III was treated with ASO ointment and group IV (reference group; Ref) was treated with a reference drug “Cytolcentella® cream”. Phytochemical screening showed that total phenols (215 ± 3.5 mg GAE/g) and flavonoids (172.4 ± 3.1 mg QE/g) were higher in the ASO than the ASE group. The results of the antioxidant properties showed that ASO exhibited the highest DPPH free radical scavenging potential (IC50 = 0.136 ± 0.07 mg/mL), FRAP test (IC50 = 0.013 ± 0.006 mg/mL), ABTS test (IC50 = 0.52 ± 0.03 mg/mL) and total antioxidant capacity (IC50 = 0.34 ± 0.06 mg/mL). In the wound healing study, topical application of ASO performed the fastest wound-repairing process estimated by a chromatic study, percentage wound closure, fibrinogen level and oxidative damage status, as compared to ASE, the Cytolcentella reference drug and the untreated rats. The use of AS extract and oil were also associated with the attenuation of oxidative stress damage in the wound-healing treated rats. Overall, the results provided that AS, particularly ASO, has a potential medicinal value to act as effective skin wound healing agent.
Experimental Investigation of the Rheological Behavior of an Oil-Based Drilling Fluid with Rheology Modifier and Oil Wetter Additives
Authors: Murtaza Mobeen , Alarifi Sulaiman A. , Kamal Muhammad Shahzad , Onaizi Sagheer A. , Al-Ajmi Mohammed , Mahmoud Mohamed
Published: August 2021

Drilling issues such as shale hydration, high-temperature tolerance, torque and drag are often resolved by applying an appropriate drilling fluid formulation. Oil-based drilling fluid (OBDF) formulations are usually composed of emulsifiers, lime, brine, viscosifier, fluid loss controller and weighting agent. These additives sometimes outperform in extended exposure to high pressure high temperature (HPHT) conditions encountered in deep wells, resulting in weighting material segregation, high fluid loss, poor rheology and poor emulsion stability. In this study, two additives, oil wetter and rheology modifier were incorporated into the OBDF and their performance was investigated by conducting rheology, fluid loss, zeta potential and emulsion stability tests before and after hot rolling at 16 h and 32 h. Extending the hot rolling period beyond what is commonly used in this type of experiment is necessary to ensure the fluid’s stability. It was found that HPHT hot rolling affected the properties of drilling fluids by decreasing the rheology parameters and emulsion stability with the increase in the hot rolling time to 32 h. Also, the fluid loss additive’s performance degraded as rolling temperature and time increased. Adding oil wetter and rheology modifier additives resulted in a slight loss of rheological profile after 32 h and maintained flat rheology profile. The emulsion stability was slightly decreased and stayed close to the recommended value (400 V). The fluid loss was controlled by optimizing the concentration of fluid loss additive and oil wetter. The presence of oil wetter improved the carrying capacity of drilling fluids and prevented the barite sag problem. The zeta potential test confirmed that the oil wetter converted the surface of barite from water to oil and improved its dispersion in the oil.
An Analytical Method for the Biomonitoring of Mercury in Bees and Beehive Products by Cold Vapor Atomic Fluorescence Spectrometry
Authors: Astolfi Maria Luisa , Conti Marcelo Enrique , Ristorini Martina , Frezzini Maria Agostina , Papi Marco , Massimi Lorenzo , Canepari Silvia
Published: August 2021

Bees and their products are useful bioindicators of anthropogenic activities and could overcome the deficiencies of air quality networks. Among the environmental contaminants, mercury (Hg) is a toxic metal that can accumulate in living organisms. The first aim of this study was to develop a simple analytical method to determine Hg in small mass samples of bees and beehive products by cold vapor atomic fluorescence spectrometry. The proposed method was optimized for about 0.02 g bee, pollen, propolis, and royal jelly, 0.05 g beeswax and honey, or 0.1 g honeydew with 0.5 mL HCl, 0.2 mL HNO3, and 0.1 mL H2O2 in a water bath (95 °C, 30 min); samples were made up to a final volume of 5 mL deionized water. The method limits sample manipulation and the reagent mixture volume used. Detection limits were lower than 3 µg kg−1 for a sample mass of 0.02 g, and recoveries and precision were within 20% of the expected value and less than 10%, respectively, for many matrices. The second aim of the present study was to evaluate the proposed method’s performances on real samples collected in six areas of the Lazio region in Italy.