bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on the Utilization Rate and Influencing Factors of Small Agricultural Machinery: Evidence from 10 Hilly and Mountainous Provinces in China
Authors: Li Hongbo , Chen Lewei , Zhang Zongyi
Published: December 2022

Hilly and mountainous areas are weak places for the development of agricultural mechanization in China. The way to improve the utilization rate of small agricultural machinery widely used in hilly and mountainous areas is of positive significance for optimizing resource allocation efficiency of agricultural production and ensuring food security supply. Taking microtillers as a representative tool, this study systematically analyzed the main factors affecting the utilization rate of small agricultural machines and its influencing mechanism. Then, based on the survey data of 4905 farmers in 100 counties in 10 hilly and mountainous provinces of China, empirical analysis was carried out by some econometric models, such as censored regression and the mediating effect model. Results show the following.: (1) Among farmers in hilly and mountainous areas, the average use time of each microtiller is 218.41 h per year. (2) Age, social identity, terrain conditions, crop types, land area, the number of microtillers, the number of large tractors, and the machinery purchase subsidy policy are the significant factors affecting the utilization rate of microtillers. (3) The increase of cultivated land area not only directly improves the utilization rate of microtillers, but also indirectly improves the utilization rate of microtillers due to the increase in quantity.
Polycyclic Aromatic Hydrocarbons (PAHs) Occurrence in Traditionally Smoked Chicken, Turkey and Duck Meat
Authors: Coroian Cristian Ovidiu , Coroian Aurelia , Becze Anca , Longodor Adina , Mastan Oana , Radu-Rusu Răzvan-Mihail
Published: December 2022

An increasingly high interest is given to the sensory, nutritional, and sanogenic qualities of meat. Considering that poultry meat is nowadays the main quantitatively demanded meat for human consumption, its quality is largely verified and monitored. Toxic compounds are trace markers to be monitored, as their health impacts often cause a high health risk for humans. We have evaluated how a traditional method of meat preservation—hot smoking with natural wood smoke—adds certain polycyclic aromatic hydrocarbons (PAHs) to chicken, duck, and turkey meat. One- vs two-day smoking period and three wood types for smoking (plum, cherry, and beech) have shown that the highest concentrations of PAHs were present in duck meat, irrespective of smoking time or wood type. A higher concentration overall of PAHs was quantified when beech wood was used, followed by cherry and plum woods. Fluorene associated with beech wood gave the highest values for day 1 and day 2, followed by duck and turkey meat, respectively. Very significant differences (p < 0.001) were usually observed for duck meat when compared with chicken and turkey meat, but it was also easy to notice absolute values for Anthracene, Phenanthrene, or Fluoranthene. As expected, two-day smoking contributed to higher concentrations of PAHs in meat.
Ukraine’s Market of Certified Seed: Current State and Prospects for the Future
Authors: Zakharchuk Oleksandr , Hutorov Andrii , Vyshnevetska Oksana , Nitsenko Vitalii , Balezentis Tomas , Streimikiene Dalia
Published: December 2022

The production of high-quality seeds and planting material is the basis for increasing the efficiency and sustainability of crop production. The main aim of this article is to develop proposals to ensure that supply meets the demand in the seed and planting material market Ukraine. The future prospects are also discussed. The paper uses statistical and comparative analysis. The patterns of foreign trade in seeds and planting material to and from Ukraine are analyzed. The high level of import dependence of Ukraine leads to excessive exposure to instability in the world seed market. The development of seed production in Ukraine is discussed and analyzed along with the ways for improving commercial circulation of seeds and planting materials. The export volumes of grains and oilseeds in 2020 were the highest of those over the last three decades and amounted to USD 18.7 million, which is almost twice more than in 2019. Corn seeds dominate in exports (72%). The volume of imports of seeds of grains and oilseeds exceeded exports by 22 times in value and, in 2020, amounted to USD 409.4 million. In the total volume of imports, imports of sunflower seeds accounted for 53%. The upward trend of seed imports has been maintained since 2010. It was the result of increased demand for imported seeds by large- and medium-sized agricultural producers. In 2020, COVID-19 gave impetus to the development of domestic seed production and foreign breeding companies within the country. Prospective ways to accelerate the development of the organization of the Ukrainian seed and planting material market are outlined. Ukraine has prospects for increasing the export of seeds of grains and oilseeds by expanding its production by foreign companies operating in Ukraine. Solving problems of competitiveness seed production in Ukraine will make it possible to strengthen the role of domestic breeding in the seed market, as well as to use the best foreign varieties through their commercial circulation.
Assessment of Soil Degradation and Hazards of Some Heavy Metals, Using Remote Sensing and GIS Techniques in the Northern Part of the Nile Delta, Egypt
Authors: Abowaly Mohamed E. , Ali Raafat A. , Moghanm Farahat S. , Gharib Mohamed S. , Moustapha Moustapha Eid , Elbagory Mohssen , Omara Alaa El-Dein , Elmahdy Shimaa M.
Published: December 2022

Soil degradation and pollution is one of the main problems threatening the sustainable development of agriculture. This study used remote sensing and geographic information system (GIS) techniques to assess the risks of soil degradation and the risks of heavy metals in some soils north of the Nile Delta. The study area suffers from salinity, alkalinity, and water logging, so a spatial degradation model was used. Relying on landsat ETM+ images and the digital elevation model (DEM), it was possible to produce a geomorphological map, and it showed that the studied area consists of two landscapes, i.e., flood plain and lacustrine plain. The results indicated that salinization, alkalization, compaction, and water logging were the main types of soil degradation in the studied area. The spatial land degradation model showed that 16.61% of soils were affected by low degrees of degradation, 74.03% were affected by moderate degrees, and 9.36% were affected by high degrees of degradation. The studied area was affected by chemical degradation risks between low and high at 90.62% and 9.37%, respectively, while the physical degradation risks varied between low, moderate, high, and very high with percentages of 9.37%, 41.53%, 40.14%, and 8.93%, respectively. The environmental risks of heavy metals were assessed in the studied area using pollution indices including, the enrichment factor (EF), the pollution load index (PLI), and the potential ecological risk index (PER).
Calibration of Soil Moisture Sensors (ECH2O-5TE) in Hot and Saline Soils with New Empirical Equation
Authors: Louki Ibrahim I. , Al-Omran Abdulrasoul M.
Published: December 2022

The use of soil moisture sensors is a practice applied to improve irrigation water management. ECH2O-5TE sensors are increasingly being used to estimate the volumetric water content (VWC). In view of the importance of the efficient use of these devices, six main factors affecting the accuracy of sensor measurements were studied: soil moisture levels, soil salinity, temperature, organic matter, soil texture, and bulk density. The study showed that the electrical conductivity of the soil and the temperature independently affect the measurements, while the influence of other factors interferes with that of salinity. This study found that the sensor measurements of the VWC were closest to the actual VWC at the soil ECe and temperatures of 2.42 dS m−1 and 25 °C, with root-mean-square errors (RMSE) of 0.003 and 0.004 m3 m−3. Otherwise, the measured VWC values of these sensor readouts significantly overestimated the actual VWC, with an increasing soil ECe and/or producing temperatures higher than the stated values, and vice versa. Given the importance of these sensors for obtaining accurate measurements for water management, a simplified empirical equation was derived using the data collected from a wide range of measurements to correct the influences of electrical conductivity and temperature on the measurement accuracy of the sensors, while considering the influence of the soil’s texture. Thus, the following equation was proposed: ϴva = θvsaECe2+bECe+c+dT2+eT+f−1. The results concerning the measurement of different VWC levels via these sensors and the proposed L&O correction equation were compared with the corresponding actual VWC values determined by gravimetric methods. It was found that this empirical equation reduced the differences in the RMSE between the sensor readings for the VWC and the actual VWC from 0.072 and 0.252 to 0.030 and 0.030 m3 m−3 for 1 and 5 dS m−1, respectively, with respect to the EC’s influence at 25 °C and reduced the RMSE from 0.053 and 0.098 to 0.007 and 0.011 at 3 and 50 °C, respectively, regarding the effect of the temperature at EC 2.42 dS m−1 at different levels of the actual VWC values.
Bean Common Mosaic Disease: Etiology, Resistance Resource, and Future Prospects
Authors: Tang Muning , Feng Xue
Published: December 2022

Bean common mosaic disease is one of the most destructive diseases of the common bean, which is one of the most important legumes worldwide. It is caused by two closely related potyviruses: bean common mosaic virus (BCMV) and bean common mosaic necrosis virus (BCMNV). Both viruses have spread to all the common bean-growing areas worldwide and have become a major challenge in bean production. In this review, we summarized the biology and diversity of BCMV and BCMNV, discussed the current knowledge on the resistance genes of BCMV, and finally pointed out the future prospects for the control of bean common mosaic disease.
Key Technologies for an Orchard Variable-Rate Sprayer: Current Status and Future Prospects
Authors: Wei Zhiming , Xue Xinyu , Salcedo Ramón , Zhang Zhihong , Gil Emilio , Sun Yitian , Li Qinglong , Shen Jingxin , He Qinghai , Dou Qingqing , Zhang Yungan
Published: December 2022

An orchard variable-rate sprayer applies the appropriate amount of plant protection products only where they are needed based on detection data from advanced sensors, a system that has attracted increasing attention. The latest developments in the detection unit, variable control unit, and signal-processing algorithm of the variable-rate sprayer are discussed. The detection of target position and volume is realized with an ultrasonic sensor, a laser scanning sensor, or other methods. The technology of real-time acquisition of foliage density, plant diseases and pests and their severity, as well as meteorological parameters needs further improvements. Among the three variable-flow-rate control units, pulse width modulation was the most widely used, followed by pressure-based, and variable concentration, which is preliminarily verified in the laboratory. The variable air supply control unit is tested both in the laboratory and in field experiments. The tree-row-volume model, the leaf-wall-area model, and the continuous application mode are widely used algorithms. Advanced research on a variable-rate sprayer is analyzed and future prospects are pointed out. A laser-based variable-rate intelligent sprayer equipped with pulse width modulation solenoid valves to tune spray outputs in real time based on target structures may have the potential to be successfully adopted by growers on a large scale in the foreseeable future. It will be a future research direction to develop an intelligent multi-sensor-fusion variable-rate sprayer based on target crop characteristics, plant diseases and pests and their severity, as well as meteorological conditions while achieving multi-variable control.
Proper Biochar Increases Maize Fine Roots and Yield via Altering Rhizosphere Bacterial Communities under Plastic Film Mulching
Authors: Sui Yanghui , Wang Yanbo , Xiao Wanxin , Chang Cheng , Zhang Shuping , Zhao Haiyan
Published: December 2022

Biochar amendment is considered a sustainable agricultural strategy to improve crop yields. However, information on grain yield, fine roots and in relation to rhizosphere microbial communities in maize under plastic film mulching is very limited. Herein, biochar applied every 2 years (8.4 t ha−1, B1) and biochar applied every 5 years (21 t ha−1, B2) combined with nitrogen (225 kg ha−1), or nitrogen alone, were tested in a field experiment. The results showed that a biochar–fertilizer application significantly decreased the root length at the V9 stage, but biochar applied every 5 years significantly maintained the root length at the R6 stage. Biochar–fertilizer application increased grain yield under the B1 treatment while slightly decreasing under the B2 treatment. The rhizosphere of maize was preferentially colonized by Proteobacteria, Firmicutes, Sphingomonas, and Bradyrhizobium. Dominant phyla including Proteobacteria were enriched in bulk soils, while Bacteroidetes and Firmicutes were depleted in rhizosphere and bulk soils under the biochar–fertilizer application. Changes in root morphology and soil properties were responsible for bacterial community structure in response to different biochar applications. Thus, we concluded that the differential responses of maize yield and root attributes might be related to the specific biochar dose-specific effects on soil microbiome diversity.
Physiological Influence of Water Stress Conditions on Novel HLB-Tolerant Citrus Rootstocks
Authors: Arjona-López Juan M. , Aparicio-Durán Lidia , Gmitter Frederick G. , Romero-Rodríguez Estefanía , Grosser Jude W. , Hervalejo Aurea , Arenas-Arenas Francisco J.
Published: December 2022

Citrus are one of the most relevant fruit crops in the Mediterranean basin, which is the second-highest citrus-growing region in the world. However, these crops are mainly grown under Mediterranean semi-arid conditions, characterized by long periods of drought and torrential rain. In this work, we have assessed the response of three promising HLB-tolerant citrus rootstocks (Orange-14, UFR-1, and B11R3T27) to the application of four water stress conditions (Control, Mild water stress, Drought, and Flooding), comparing them with Carrizo citrange. Aerial plant symptoms were recorded during the experimental period, whereas plant water parameters, including stomatal conductance, leaf water potential, and relative water content, were obtained at the end of the assay. For all assessed rootstocks and variables, drought treatment was the most limiting factor, with Carrizo citrange being the most suitable rootstock under this condition. Flooding was the second restrictive treatment, in which UFR-1 was the least affected rootstock. Mid-water stress with 50% water requirements did not differ from the Control treatment, which can help save water resources in semi-arid regions. This information can be helpful for the citrus industry to increase the efficiency of citrus crops subject to water stress in semi-arid regions.
Early and Late Season Nutrient Stress Conditions: Impact on Cotton Productivity and Quality
Authors: Amissah Solomon , Baidoo Michael , Agyei Benjamin K. , Ankomah Godfred , Black Roger A. , Perry Calvin D. , Hollifield Stephanie , Kusi Nana Yaw , Harris Glendon H. , Sintim Henry Y.
Published: December 2022

Modern cotton (Gossypium spp. L) cultivars are efficient in nutrient uptake and utilization, and thus, may potentially tolerate nutrient stress. Early- and late-season nutrient stress (E-stress and L-stress, respectively) effects on cotton productivity and quality were assessed under different production conditions in Camilla and Midville, GA, USA. The E-stress received no nutrient application in the early season, but the full rates were split-applied equally at the initiation of squares and the second week of bloom stages. The L-stress received 30–40% of the full nutrient rates only at the initial stage of planting. The effects of nutrient stress on cotton productivity and fiber quality were not consistent across the different production conditions. Compared to the full nutrient rate, the E-stress did not adversely impact cotton yield, but rather it improved the lint and cottonseed yields under one production condition by 17.5% and 19.3%, respectively. Averaged across all production conditions, the L-stress decreased the lint and cottonseed yields by 34.4% and 36.2%, respectively. The minimal effects of E-stress on cotton suggest nutrient rates at the early season could be reduced and more tailored rates, informed by soil and plant tissue analyses, applied shortly before the reproductive phase.
Response of Water Radiation Utilization of Summer Maize to Planting Density and Genotypes in the North China Plain
Authors: Liu Zhendong , Wei Shiyu , Li Ming , Zhang Qingfen , Zong Rui , Li Quanqi
Published: December 2022

Increasing the planting density of summer maize to improve the utilization efficiency of limited soil and water resources is an effective approach; however, how the leaf water-use efficiency (WUEL), yield, and RUE respond to planting density and genotypes remains unclear. A 2-year field experiment was performed in the North China Plain (NCP) to investigate the effects of planting density (high, 100,000 plants ha−1; medium, 78,000 plants ha−1; and low, 56,000 plants ha−1) and genotypes (Zhengdan 958 and Denghai 605) on the leaf area index (LAI), photosynthetic characteristics, dry-matter accumulation, WUEL, and RUE of maize. The objective was to explore the effect of density and genotype on the WUEL and RUE of maize. Increasing planting density boosted LAI, light interception, dry-matter accumulation, and spike number but reduced the chlorophyll content, net photosynthetic rate, transpiration rate, and 1000-kernel weight. Both high and low planting densities were averse to RUE and yield. Zhengdan 958 increased the WUEL by 19.45% compared with Denghai 605, but the RUE of Denghai 605 was 18.19% higher than Zhengdan 958, suggesting that Denghai 605 had a greater production potential as the planting density increased. Our findings recommend using 78,000 plants ha−1 as the planting density with Denghai 605 to maintain summer maize yields in the NCP.
Seed Priming of Rice Varieties with Decoyinine Improve Their Resistance against the Brown Planthopper Nilaparvata lugens
Authors: Xu Gang , She Shengyao , Gui Wei , Ma Chao , Zhang Yuanyuan , Qian Mingshi , Yang Guoqing
Published: December 2022

The brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae) is one of the most destructive rice pests in Asia. The microbial metabolite decoyinine (DCY) has been extracted from Streptomyces hygroscopicus. Recent studies have suggested that treating rice seeds with DCY could improve the growth and yield of rice. To further assess the effects of priming the seeds of different rice varieties with DCY on rice seedling resistance against BPH, an age-stage, two-sex life table and choice test were applied to investigate the individual fitness, population parameters, and preference behavior of BPHs in this study. The results indicated that feeding on rice seedlings grown from seeds primed with DCY significantly affected BPHs’ adult longevity, oviposition period, fecundity, as well as the net reproductive rate (R0), intrinsic rate of increase (rm), finite rate of increase (λ), doubling time (DT), and population size in terms of BPH. The honeydew excretions and the weights of BPHs fed on DCY-pretreated rice plants were remarkably lowered. The two-way ANOVA results also showed that there were significant differences in the biological parameters, honeydew excretions, and of BPH weights owing to DCY treatment, rice variety, and the interactions between DCY treatment and rice variety. Additionally, the feeding and oviposition preferences of BPHs for the pretreated rice plants were reduced. Our results imply that the priming of seeds with DCY can improve rice resistance against BPH, which could facilitate the utilization of seed priming as a new avenue for effective crop protection.
Effects of Microplastics Addition on Soil Available Nitrogen in Farmland Soil
Authors: Liu Weili , Cao Zhi , Ren Haiyan , Xi Dan
Published: December 2022

As microplastics (MPs) are an emerging pollution to farmland ecosystems, the research into the ecological and environmental effects of MPs need to be clarified urgently. Available nitrogen is the determining factor for productivity in most terrestrial ecosystems, especially for the farmland ecosystems with a high productivity. To explore the effects of MPs on soil available nitrogen in farmland soil, an incubation experiment was conducted by adding polyethylene MPs with different concentrations to farmland soil, which was collected from farmland in Fuqing, Fujian Province. The contents of three different nitrogen forms (nitrate, ammonium, and dissolved organic nitrogen) and soil dissolved organic carbon were measured, and the soil mineralization rate was calculated. Bacteria was quantified and bacterial community diversity indexes were measured. The results showed that the MPs addition (T1 and T2) had no significant effect on soil ammonium, nitrate and soil nitrogen mineralization rate compared to the control (p > 0.05). However, a significant increase was observed in soil dissolved organic carbon and dissolved organic nitrogen content (p < 0.05). It can be seen that the influence of PE MPs on the soil dissolved organic nitrogen is greater than that of inorganic nitrogen. The results of this study showed no major detrimental effects of MPs on the abundance of some bacterial families, whereas a significant change in soil bacterial evenness index was observed in T2 treatment compared to the treatment without MPs addition. In the background of current MPs pollution, the research results can provide a scientific basis for reducing nitrogen loss in soil and protecting farmland soil safety.
QTL Mapping of Mineral Element Contents in Rice Using Introgression Lines Derived from an Interspecific Cross
Authors: Adeva Cheryl , Yun Yeo-Tae , Shim Kyu-Chan , Luong Ngoc Ha , Lee Hyun-Sook , Kang Ju-Won , Kim Hyun-Jung , Ahn Sang-Nag
Published: December 2022

Developing rice varieties with increased mineral element content is the most cost-effective and efficient approach for alleviating human malnutrition and nutrient deficiencies. In this study, quantitative trait loci (QTLs) were mapped for mineral element content in 96 introgression lines derived from a cross between the elite Korean Oryza sativa japonica cultivar “Hwaseong” and the wild rice Oryza rufipogon (IRGC105491). The population was grown in two locations, and Fe, Zn, Mn, and Ca contents of the brown rice were measured. Six QTLs were identified on chromosomes 6, 8, and 10, and all O. rufipogon alleles increased trait values. The positions of qFe10 and qZn10 were further defined; higher Fe and Zn contents are related to the 375-kb O. rufipogon segment between the markers RM1873 and RM25612. The combined analysis of the whole-genome sequencing data, spatiotemporal expression profile, and gene expression suggested that a transcription factor gene, namely the rice homeobox gene 9 (LOC_Os10g33960) marks as the high potential candidate associated with Fe and/or Zn regulation. This study provides valuable information on candidate genes qFe10 and qZn10 from O. rufipogon, which may be vital in developing rice varieties with increased Fe and/or Zn content without any penalty in traits of agronomic importance.
Antimicrobial Potential of Metabolites in Fungal Strains Isolated from a Polluted Stream: Annulohypoxylon stygium WL1B5 Produces Metabolites against Extended-Spectrum Beta-Lactamase-Positive Escherichia coli
Authors: Segundo Walter Oliva Pinto Filho , de Oliveira Roberta Silva , Lima Rildo Mendes , Santiago Paulo Alexandre Lima , de Oliveira Luciana Aires , Cortez Ana Cláudia Alves , Lima Emerson Silva , de Souza Érica Simplício , Frickmann Hagen , de Souza João Vicente Braga
Published: December 2022

The emergence of multidrug resistance in bacterial pathogens is a growing public health concern requiring solutions including the discovery of new antimicrobial drugs. Fungi have been used for decades as a source of antimicrobials. Ongoing screenings for newly characterized fungal strains producing antimicrobials include environments that are difficult to access like the deep sea, glaciers, wastewaters and environments polluted due to human activity. In the present study, fungal microorganisms were isolated from water samples taken from a polluted stream in the city of Manaus, AM, Brazil, and screened for antimicrobial effects against Escherichia coli. Using extracts from five isolates (Annulohypoxylon stygium WL1B5, Colletotrichum fructicola WL3B9, Clonostachys rosea WL5B18, Clonostachys rosea WL8B28 and Trichoderma harzianum WL9B49), antimicrobial activity against the reference strains Escherichia coli ATCC 25922 as well as E. coli NCTC 13353, an extended-spectrum beta-lactamase-positive strain, was observed. Inhibition zones ranged from 1 to 35.9 mm and a minimum inhibitory concentration of 400 µg/mL could be demonstrated. Assessments of the metabolites of Annulohypoxylon stygium WL1B5 allowed us to identify nodulisporone and daidzein, which have already been associated with antimicrobial activity. The findings confirm the feasibility of isolating fungal strains from polluted sites producing metabolites that can serve as potential future alternatives for the treatment of multidrug-resistant bacteria.
Rapid Detection of Carbapenemase and Extended-Spectrum β-Lactamase Producing Gram-Negative Bacteria Directly from Positive Blood Cultures Using a Novel Protocol
Authors: Josa Diego , Bustos Ingrid , Yusef Soad , Crevoisier Stephanie , Silva Edwin , López Natalia , Leal Rafael , Molina Isabel , Osorio Juan , Arias Gerson , Cortés-Muñoz Fabián , Sánchez Carolina , Reyes Luis
Published: December 2022

Background: Early and adequate antibiotic treatment is the cornerstone of improving clinical outcomes in patients with bloodstream infections (BSI). Delays in appropriate antimicrobial therapy have catastrophic consequences for patients with BSI. Microbiological characterization of multi-drug resistant pathogens (MDRP) allows clinicians to provide appropriate treatments. Current microbiologic techniques may take up to 96 h to identify causative pathogens and their resistant patterns. Therefore, there is an important need to develop rapid diagnostic strategies for MDRP. We tested a modified protocol to detect carbapenemase and extended-spectrum β-lactamase (ESBL) producing Gram-negative bacteria (GNB) from positive blood cultures. Methods: This is a prospective cohort study of consecutive patients with bacteremia. We developed a modified protocol using the HB&L® system to detect MDRP. The operational characteristics were analyzed for each test (HB&L-ESBL/AmpC® and HB&L-Carbapenemase® kits). The kappa coefficient, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios (LR) with 95% confidence intervals (CI), and reduction in identification time of this novel method were calculated. Results: Ninety-six patients with BSI were included in the study. A total of 161 positive blood cultures were analyzed. Escherichia coli (50%, 81/161) was the most frequently identified pathogen, followed by Klebsiella pneumoniae (15%, 24/161) and Pseudomonas aeruginosa (8%, 13/161). Thirty-three percent of isolations had usual resistance patterns. However, 34/161 (21%) of identified pathogens were producers of carbapenemases and 21/161 (13%) of extended-spectrum β-lactamases. Concordance between our HB&L® modified protocol and the traditional method was 99% (159/161). Finally, identification times were significantly shorter using our HB&L®-modified protocol than traditional methods: median (IQR) 19 h (18, 22) vs. 61 h (60, 64), p < 0.001. Conclusions: Here, we provide novel evidence that using our HB&L®-modified protocol is an effective strategy to reduce the time to detect MDRP producers of carbapenemases or extended-spectrum β-lactamases, with an excellent concordance rate when compared to the gold standard. Further studies are needed to confirm these findings and to determine whether this method may improve clinical outcomes.
Newly Discovered Mechanisms of Antibiotic Self-Resistance with Multiple Enzymes Acting at Different Locations and Stages
Authors: Chen Xiaorong , Pan Hai-Xue , Tang Gong-Li
Published: December 2022

Self-resistance determinants are essential for the biosynthesis of bioactive natural products and are closely related to drug resistance in clinical settings. The study of self-resistance mechanisms has long moved forward on the discovery of new resistance genes and the characterization of enzymatic reactions catalyzed by these proteins. However, as more examples of self-resistance have been reported, it has been revealed that the enzymatic reactions contribute to self-protection are not confined to the cellular location where the final toxic compounds are present. In this review, we summarize representative examples of self-resistance mechanisms for bioactive natural products functional at different cell locations to explore the models of resistance strategies involved. Moreover, we also highlight those resistance determinants that are widespread in nature and describe the applications of self-resistance genes in natural product mining to interrogate the landscape of self-resistance genes in drug resistance-related new drug discovery.
Staphylococcal Scalded Skin Syndrome in Neonates: Case Series and Overview of Outbreaks
Authors: Nusman Charlotte M. , Blokhuis Charlotte , Pajkrt Dasja , Visser Douwe H.
Published: December 2022

Skin and soft tissue infections caused by Staphylococcus aureus (S. aureus) cover a wide spectrum of diseases in neonates, including staphylococcal scalded skin syndrome (SSSS). We describe a representative case of SSSS in neonatal twins, which despite recurrence showed a mild clinical disease course. This case was part of a small outbreak on a neonatal intensive care unit and therefore exemplifies the existence of neonatal outbreaks with skin and soft tissue infections by S. aureus. Diagnosis is generally based on the clinical picture and response to antibiotics, but can be aided by histology and cultures. Sequence-based molecular techniques are available to evaluate typing and virulence of S. aureus in outbreak or surveillance settings. The pillars of treatment are antibiotics and supportive care. Methicillin resistance remains a topic of concern, especially in outbreak settings. Our overview of numerous outbreaks of neonatal S. aureus skin infections underlines the importance of outbreak management strategies, including screening to identify the source of the outbreak, and limiting exposure through hygienic measures and establishment of physical boundaries.
Novel, Innovative Models to Study Ischemia/Reperfusion-Related Redox Damage in Organ Transplantation
Authors: Hofmann Julia , Pühringer Marlene , Steinkellner Sabrina , Holl Aline-Sophie , Meszaros Andras T. , Schneeberger Stefan , Troppmair Jakob , Hautz Theresa
Published: December 2022

The implementation of ex vivo organ machine perfusion (MP) into clinical routine undoubtedly helped to increase the donor pool. It enables not just organ assessment, but potentially regeneration and treatment of marginal organs in the future. During organ procurement, redox-stress triggered ischemia-reperfusion injury (IRI) is inevitable, which in addition to pre-existing damage negatively affects such organs. Ex vivo MP enables to study IRI-associated tissue damage and its underlying mechanisms in a near to physiological setting. However, research using whole organs is limited and associated with high costs. Here, in vitro models well suited for early stage research or for studying particular disease mechanisms come into play. While cell lines convince with simplicity, they do not exert all organ-specific functions. Tissue slice cultures retain the three-dimensional anatomical architecture and cells remain within their naïve tissue-matrix configuration. Organoids may provide an even closer modelling of physiologic organ function and spatial orientation. In this review, we discuss the role of oxidative stress during ex vivo MP and the suitability of currently available in vitro models to further study the underlying mechanisms and to pretest potential treatment strategies.
Protective Effects of Therapeutic Neutrophil Depletion and Myeloperoxidase Inhibition on Left Ventricular Function and Remodeling in Myocardial Infarction
Authors: Guthoff Henning , Hof Alexander , Klinke Anna , Maaß Martina , Konradi Jürgen , Mehrkens Dennis , Geißen Simon , Nettersheim Felix S. , Braumann Simon , Michaelsson Erik , Nies Richard J. , Lee Samuel , Redzinski Marie-Christin , Peters Vera B. M. , Nemade Harshal N. , von Stein Philipp , Winkels Holger , Rudolph Volker , Baldus Stephan , Adam Matti , Mollenhauer Martin
Published: December 2022

Myocardial infarction (MI) is a leading cause of morbidity and mortality worldwide. Improved survival has led to an increasing incidence of ischemic cardiomyopathy, making it a major reason for hospitalization in the western world. The inflammatory response in the ischemic myocardium determines the extent of structural remodeling and functional deterioration, with neutrophils (PMN) being a key modulator of the propagation and resolution of inflammation. The heme enzyme myeloperoxidase (MPO) is abundantly expressed in PMN and is an important mediator of their inflammatory capacities. Here, we examine the effects of PMN reduction, MPO deficiency and MPO inhibition in two murine models of MI. Reduction in PMN count resulted in less scar formation and improved cardiac function. Similar results were obtained in genetically MPO deficient mice, suggesting that MPO is a critical factor in PMN-mediated cardiac remodeling. To test our findings in a therapeutic approach, we orally administered the MPO inhibitor AZM198 in the context of MI and could demonstrate improved cardiac function and reduced structural remodeling. Therefore, MPO appears to be a favorable pharmacological target for the prevention of long-term morbidity after MI.
Synthesis and Antioxidant Properties of Novel 1,2,3-Triazole-Containing Nitrones
Authors: Hadjipavlou-Litina Dimitra , Głowacka Iwona E. , Marco-Contelles José , Piotrowska Dorota G.
Published: December 2022

Herein, we report the synthesis and antioxidant capacity of twelve novel 1,2,3-triazole-containing nitrones such as N-(2-(4-aryl-1H-1,2,3-triazol-1-yl)ethylidene)methanamine oxides 8a–f and N-(2-(4-aryl)-1H-1,2,3-triazol-1-yl)ethylidene)-2-methylpropan-2-amine oxides 9a–f, bearing an N-methyl, and an N-t-butyl substituent, respectively, at the nitrogen of the nitrone motif. Nitrones 8 and 9 were studied with regard to their antioxidant ability, as well as their ability to inhibit soybean lypoxygenase (LOX), and their in vitro antioxidant activity. For this, we used three different antioxidant assays, such as that featuring the interaction with the water-soluble azo compound AAPH for the inhibition of lipid peroxidation (LP), the competition with the DMSO for scavenging hydroxyl radicals, and the ABTS•+–decolorization assay. t-Butyl nitrone 9e, bearing the 2,4-difluorophenyl motif, showed a strong LP inhibitory effect (100%), close to the reference compound Trolox (93%), being the most potent LP inhibitor (LPi) of the whole series of tested nitrones. Nitrones 9d, 9e and 9f, bearing the 4-fluorophenyl, 2,4-difluorophenyl, and 4-fluoro-3-methylphenyl motif, respectively, were almost equipotent, and the most potent hydroxyl radical scavengers (~100%), more potent than Trolox (88%), were used as a reference compound. Regarding the LOX inhibition, the most potent inhibitor was the t-butyl substituted nitrone 9f (27 μM), bearing the 4-fluoro-3-methylphenyl motif, being 60-fold less potent than NDGA (0.45 μM), which was used as the standard in this test. The results from the antioxidant determination in the ABTS radical cation (ABTS•+) decolorization assay were not significant. N-Methyl nitrone 8f, bearing the 4-fluoro-3-methylphenyl motif, was the only promising representative, with a value of 34.3%, followed by nitrone 9f (16%). From the antioxidant analyses, we have identified N-(2-(4-(4-fluoro-3-methylphenyl)-1H-1,2,3-triazol-1-yl)ethylidene)-2-methylpropan-2-amine oxide (9f), bearing t-butyl and 4-fluoro-3-methylphenyl motifs in its structure, as the most balanced and potent antioxidant agent among the tested nitrones, as it was the most potent LOX inhibitor (27 μM), an extremely efficient and potent hydroxyl radical scavenger (99.9%), as well as one of the most potent LPi (87%) and ABTS•+ scavengers (16%).
Time-Dependent Oxidative Alterations in Plasma and Lung Tissue after Meconium Aspiration in a Rabbit Model
Authors: Kosutova Petra , Nemcova Nikolett , Kolomaznik Maros , Mokra Daniela , Calkovska Andrea , Mikolka Pavol
Published: December 2022

Aspirated meconium into a newborn’s airways induces the transcription of pro-oxidative mediators that cooperate in the pathogenesis of inflammatory changes and may negatively affect the commonly used exogenous surfactant therapy. However, inflammation is not treated at present, nor is the time dependence of oxidative damage known. The aim of our study was to describe the time course of oxidative stress marker production during meconium aspiration syndrome (MAS) and its relationship to leukocyte infiltration. New Zealand rabbits were instilled with saline or meconium suspension and ventilated for 5.5 h. Respiratory parameters were recorded and blood samples were taken before meconium application and in time intervals of 15 and 30 min, 1.0, 1.5, 3.5 and 5.5 h after application to evaluate oxidative markers and differential leukocytes count. Meconium aspiration led to a worsening of respiratory parameters and a decrease in leukocytes in the first 15 min. Changes in leukocytes were correlated both with nitrotyrosine (3NT) levels and thiobarbituric acid reactive substance (TBARS) levels, with the latter also related to changes in neutrophil count. The production of 3NT and TBARS increased in 1.5 and 3.5 h, respectively, in different ways, suggesting more than one source of oxidative agents and a potential risk of exogenous surfactant inactivation in a short time. We observed that MAS triggered neutrophil migration to the alveolar space and activation, as shown by the increased expression of pro-inflammatory cytokines and generation of indicators of oxidative damage to proteins and lipids during the time period when iNOS and NO metabolites were released.
Exercise Training and Skeletal Muscle Antioxidant Enzymes: An Update
Authors: Powers Scott K. , Goldstein Erica , Schrager Matthew , Ji Li Li
Published: December 2022

The pivotal observation that muscular exercise is associated with oxidative stress in humans was first reported over 45 years ago. Soon after this landmark finding, it was discovered that contracting skeletal muscles produce oxygen radicals and other reactive species capable of oxidizing cellular biomolecules. Importantly, the failure to eliminate these oxidant molecules during exercise results in oxidation of cellular proteins and lipids. Fortuitously, muscle fibers and other cells contain endogenous antioxidant enzymes capable of eliminating oxidants. Moreover, it is now established that several modes of exercise training (e.g., resistance exercise and endurance exercise) increase the expression of numerous antioxidant enzymes that protect myocytes against exercise-induced oxidative damage. This review concisely summarizes the impact of endurance, high-intensity interval, and resistance exercise training on the activities of enzymatic antioxidants within skeletal muscles in humans and other mammals. We also discuss the evidence that exercise-induced up-regulation of cellular antioxidants reduces contraction-induced oxidative damage in skeletal muscles and has the potential to delay muscle fatigue and improve exercise performance. Finally, in hopes of stimulating further research, we also discuss gaps in our knowledge of exercise-induced changes in muscle antioxidant capacity.
Fundamental Role of Pentose Phosphate Pathway within the Endoplasmic Reticulum in Glutamine Addiction of Triple-Negative Breast Cancer Cells
Authors: Marini Cecilia , Cossu Vanessa , Carta Sonia , Greotti Elisa , Gaglio Daniela , Bertola Nadia , Chiesa Sabrina , Bruno Silvia , Vitale Francesca , Bonanomi Marcella , Porro Danilo , Riondato Mattia , Orengo Anna Maria , Bauckneht Matteo , Morbelli Silvia , Ravera Silvia , Sambuceti Gianmario
Published: December 2022

Cancer utilization of large glutamine equivalents contributes to diverging glucose-6-P flux toward the pentose phosphate shunt (PPP) to feed the building blocks and the antioxidant responses of rapidly proliferating cells. In addition to the well-acknowledged cytosolic pathway, cancer cells also run a largely independent PPP, triggered by hexose-6P-dehydrogenase within the endoplasmic reticulum (ER), whose activity is mandatory for the integrity of ER–mitochondria networking. To verify whether this reticular metabolism is dependent on glutamine levels, we complemented the metabolomic characterization of intermediates of the glucose metabolism and tricarboxylic acid cycle with the estimation of proliferating activity, energy metabolism, redox damage, and mitochondrial function in two breast cancer cell lines. ER-PPP activity and its determinants were estimated by the ER accumulation of glucose analogs. Glutamine shortage decreased the proliferation rate despite increased ATP and NADH levels. It depleted NADPH reductive power and increased malondialdehyde content despite a marked increase in glucose-6P-dehydrogenase. This paradox was explained by the deceleration of ER-PPP favored by the decrease in hexose-6P-dehydrogenase expression coupled with the opposite response of its competitor enzyme glucose-6P-phosphatase. The decreased ER-PPP activity eventually hampered mitochondrial function and calcium exchanges. These data configure the ER-PPP as a powerful, unrecognized regulator of cancer cell metabolism and proliferation.
Skin Improvement with Antioxidant Effect of Yuja (Citrus junos) Peel Fractions: Wrinkles, Moisturizing, and Whitening
Authors: Jung Young Yun , Ha In Jin , Lee Mina , Ahn Kwang Seok
Published: December 2022

Yuja (Citrus junos) has been cultivated and used for food and medicinal purposes in China and Korea. Its antioxidant, anti-wrinkle, moisturizing, and whitening effects were evaluated in HaCaT, HDF, and B16F10 cells. UVB has been known to cause cellular stress and the production of reactive oxygen species (ROS). Ambivalence of oxidative stress has been reported; however, excessive levels of ROS contribute to skin aging through the loss of elasticity and collagen fibers of connective tissue in the dermis. Skin aging is one of the biological processes that is affected by various factors, including UVB. Pro-Collagen I and hyaluronic acid contents were measured in UVB-irradiated HaCaT and HDF cells to evaluate the anti-wrinkle and moisturizing effects of Yuja-peel (YJP) fractions in -EA (ethyl acetate), -Hex (hexane), and -BuOH (butanol). The expression of matrix metalloproteinases (MMPs) involved in collagen degradation was confirmed to be inhibited by YJP fractions at both the protein and mRNA levels. Filaggrin and serine palmitoyltransferase (SPT), which are moisturizing factors, were induced by YJP fractions. B16F10 cells were treated with α-MSH to induce hyperpigmentation, and then the whitening efficacy of YJP fractions was verified by observing a decrease in melanin content. Overall, our results contribute to the development of various novel skin-improving cosmetics and pharmaceuticals with YJP fractions as active ingredients.
Reviewing Automated Analysis of Feature Model Solutions for the Product Configuration
Authors: Vidal-Silva Cristian , Duarte Vannessa , Cardenas-Cobo Jesennia , Serrano-Malebran Jorge , Veas Iván , Rubio-León José
Published: December 2022

Feature models (FMs) appeared more than 30 years ago, and they are valuable tools for modeling the functional variability of systems. The automated analysis of feature models (AAFM) is currently a thriving, motivating, and active research area. The product configuration of FMs is a relevant and helpful operation, a crucial activity overall with large-scale feature models. The minimal conflict detection, the diagnosis of in-conflict configuration, and the product completion of consistent partial configuration are significant operations for obtaining consistent and well-defined products. Overall, configuring products for large-scale variability intensive systems (VIS) asks for efficient automated solutions for minimal conflict, diagnosis, and product configuration. Given the relevance of minimal conflict, diagnosis, and product configuration, and the current application of large-scale configuration and FMs for representing those systems and products, the main goals of this research paper are to establish the fundaments of the product configuration of feature models and systematically review existing solutions for the conflict detection, diagnosis, and product completion in FMs from 2010 to 2019. We can perceive that even though modern computing approaches exist for AAFM operations, no solutions exist for assisting the product configurations before 2020. This article reports that in 2020, new solutions appear regarding applying parallel computing for those goals. This research highlights research opportunities for developing new and more efficient solutions for conflict detection, diagnosis, and product completion of large-scale configurations.
Effects of Life-Long Supplementation of Potassium Nitrate on Male Mice Longevity and Organs Pathology
Authors: Liubertas Tomas , Poderys Liudas Jonas , Zigmantaite Vilma , Capkauskiene Sandrija , Trakimas Giedrius , Pukenas Kazimieras , Viskelis Pranas
Published: December 2022

Many short-term studies with dietary nitrate supplementation in humans and animal models reported positive effects on the cardiovascular system, exercise efficiency, and immune function. However, there has been long-standing concern related to cancer and adverse hormonal effects. We studied the long-term effects of different potassium nitrate (KNO3) concentrations on laboratory mice longevity and structural changes in their organs. Four groups of male mice were treated with 0 mg (0%), 45 mg (1%), 90 mg (2%), and 140 mg (3%) KNO3 in the drinking water. The groups were monitored for agility and health status daily. The lifespan of mice and organ pathological changes were analyzed. We found no detrimental effects of life-long supplementation of KNO3 on the survival of mice in treatment groups. Nitrate supplementation was associated with a lower level of pathological changes (p = 0.002). We conclude that KNO3 supplementation had no carcinogenic effect on mice and possibly prevented the organs from aging.