bluuebunny/crossref_metadata_2025 huggingface dataset:
Paraburkholderia sp. GD17 improves rice seedling tolerance to salinity
Authors: Zhu Ruanming , Cao Yuting , Li Guangzhe , Guo Ying , Ma Lianju , Bu Ning , Hao Lin
Published: June 2021

​Background and aims The plant growth promoting rhizobacteria have been extensively implicated in plant responses to changing environments. However, the action mechanisms still need to be elucidated. This study addressed the effect of Paraburkholderia sp. GD17 on rice seedlings in responses to salt stress. Methods The experiment consisted of GD17-inoculated and non-inoculated plants, with or without NaCl treatment. Physiological and biochemical parameters, and gene expression were analyzed. Results GD17 efficiently colonized inside roots, and provided a protection against salt stress. Following exposure to 68 mM of NaCl for 48 h, although the accumulation of Na+ was not affected in GD17-inoculated (+GD17) roots relative to non-inoculated ones, its concentration was substantially reduced in +GD17 shoots. The contents of K and other mineral elements were higher in +GD17 plants. The expression of Na+ and K+ transporter-encoding genes generally presented a higher level in +GD17 plants. The antioxidative defense especially related to the removal of H2O2 was more strongly activated in +GD17 plants. Correspondingly, salt-induced oxidative damage was significantly ameliorated. A substantial increase in proline content and gene expression was observed in +GD17 plants. Additionally, the cell wall invertase-encoding gene displayed a dramatically higher expression level in +GD17 plants. Conclusions GD17 efficiently improved rice seedling tolerance to salt stress. The possible mechanisms might be associated with the absorption and redistribution of mineral elements, the vacuolar sequestration of Na+ as well as exclusion of Na+, antioxidative defense, the production of proline, and the sucrose catabolism in apoplast.
Fibroblast Growth Factor 21 Ameliorates Hyperuricemic Nephropathy By Improving Oxidative Stress Through Activating Akt/Nrf2 Signaling Pathway
Authors: Jiang Xinghao , Zou Yimeng , opoku Yeboah Kwaku , Liu Shijie , Wang Dan , Kang Kai , Li Deshan , Ren Guiping
Published: June 2021

Epidemiological investigations have shown an elevated expression of circulating fibroblast growth factor 21 (FGF21) of patients with hyperuricemia. However, the effect of FGF21 on hyperuricemic nephropathy (HN) is still unknown. The purpose of this study, therefore, was to explore the effect and mechanism of action of FGF21 on HN. The level of FGF21 in peripheral blood mononuclear cells (PBMCs) was determined in 10 patients with HN. In vivo models of HN were induced in C57BL/6 mice. Six mice in each group were treated with FGF21 at a dose of 1mg/kg and 5mg/kg for 30 days. For the in vitro studies, glomerular mesangial cells (GMCs) were exposed to lipopolysaccharide and monosodium uric acid to induce inflammation and oxidative stress. This was followed by treatment with 100nM, 1000nM of FGF21 for 72 h to observe the therapeutic effect. The levels of FGF21 in patients with HN were elevated. Also, we found that exogenous injection of FGF21 could significantly improve kidney injury in HN mice. This was characterized by a decrease in inflammatory factors and fibrosis and the improvement of oxidative stress. FGF21 recorded a significant therapeutic effect through the activation of Nrf2 in both in vivo and in vitro studies. However, the effect of enhancement of FGF21 on Nrf2 was reduced by the addition of Akt inhibitor GSK690693. In conclusion, our study found for the first time that FGF21 can significantly improve HN through the promotion of the Akt/Nrf2 signalling pathway leading to improvement in oxidative stress.
The Correlation between ATP Measurement and Microbial Contamination of Inanimate Surfaces
Authors: Arkel Andreas van , Willemsen Ina , Kluytmans Jan
Published: June 2021

Background:The objective of this study was to determine the correlation between adenosine triphosphate (ATP) measurements and microbial contamination using a standardized method. Secondarily, analyzing reproducibility of ATP measurements and aerobic colony counts (ACC’s) on the same surface. Methods: ATP measurements and ACC’s were conducted on 10 pre-defined fomites in a hospital and nursing home setting. Per fomite two ATP measurements and two agar plate measurements were conducted, each measurement was conducted on a 25 cm2 surface. Both measurements were compared and analyzed for correlation.Results: In total 200 paired measurements were conducted, 200 ATP measurements and 200 ACC’s. The mean of all ATP measurements tested on the same surface was calculated, as was for all 200 ACC’s. There was a strong correlation between the mean of two ATP measurements on two different sites on the same fomite (R=0.800, p<0.001) as well as between two ACC measurements on the same fomite (R=0.667, p<0.001). A much weaker correlation was found between RLU values and ACC’s (R=0.244, p<0.001). Conclusions: Reproducibility of ATP measurements and ACC’s on the same fomite was good. However, the correlation between RLU values and ACC’s on hospital surfaces was much lower. This may be explained by the wide variety of biological material that is measured with ATP, of which the bacterial load is only one of many components. ATP measurement can be used to give a quantifiable outcome for the rating of cleanliness in health care facilities, however the results cannot be translated into the level of microbial contamination.
Geotechnical aspects of Alluvial soils at different depths under sodium chloride action, Najran region, Saudi Arabia: Field supported by laboratory tests
Authors: Aal Ahmed Abd El , Abdullah Gamil
Published: June 2021

The present work is to investigated the effect of sodium chloride (NaCl) on the behavior of semi-arid soils in the Najran region of Saudi Arabia. An experiment work was carried out to investigate how the addition of (NaCl) "salt" to semi-arid soils collected from Najran region affects the Atterberg limits, compaction characteristics, California Bearing Ratio (CBR) and shear strength. All tests were performed on soils samples collected from different areas in Najran region at various depths of 1.5, 3, and 4.5 m along soil profiles. Soils samples were tested alone and then compared with the same soils samples mixed with sodium chloride (salt) at different percentages of 5, 10, and 20% respectively. Using advanced techniques, such as the scanning electron microscope (SEM), energy dispersive x-ray analysis (EDX) and X-ray diffraction analysis (XRD), the process of stabilization was examined. The results showed that salt has a major impact on the geotechnical characteristics of semi-arid soils. With the addition of sodium chloride, the maximum dry density increased and the optimal water content decreased with the increase in the added salt percentage. The liquid and plastic limits and, in turn, plasticity index reduced as the added percentage of sodium chloride increased. Furthermore, significant increase in CBR and shear strength parameters was noticed. It is therefore concluded that, the sodium chloride could be a good stabilizing agent, particularly at 20% and could be used as a sub-base material in road construction. Technical and economic advantages arise from the implementation of NaCl.
WITHDRAWN: Atropine Reverts the Neurobehavioral Toxicity Elicited by Acute Exposure to Buprofezin in Sprague Dowley Rats
Authors: muhammad aslam
Published: June 2021

Buprofezin (BPFN) is a thiadiazine insecticide that inhibits chitin synthesis and the moulting in case of white flies, mealybugs and leaf hoppers. The exposed insects are unable to shed their cuticle and ultimately die as moulting ensue. Neurobehavioral toxic effects elicited by buprofezin remained unclear. Furthermore, the reversal of buprofezin induced neurobehavioral toxicity by atropine was not elaborated. Thus, we explored the neurobehavioral toxic consequences of acute buprofezin exposure in adult male rats and effective reversal of these changes by pretreatment with atropine as an antidote. Acute administration of commercial buprofezin (87.9mg/kg/day through oral gavage with corn oil as vehicle) induce a wide range of neurobehavioral toxicity including damage to pyramidal cells of hippocampal CA1, and CA3,region and behavioral impairments as demonstrated through, loss of motor coordination, locomotor activity, fear loss, hearing, sensorimotor, cognitive and spatial navigation impairment following the exposure .These neurobehavioral toxic effect of acute buprofezin exposure were significantly reversed by the 15 min pre-treatment of atropine antidote before the buprofezin administration. Pre-treated atropine (20mg/kg/day;i.p) attenuates the neurobehavioral toxicity induced by buprofezin in male rats. It was suggested that acute buprofezin exposure elevated the acetylcholine level, by inhibiting the synthesis and release of acetylcholine esterase (AChE) in synapse. But the complete mechanisms are remained to be elucidated
Effects of uric acid, creatinine clearance, and infusion duration on the population pharmacokinetics of meropenem in critically ill patients
Authors: Zhao Yi Chang , Zou Yang , Xiao Yi Wen , Wang Feng , Zhang Bi Kui , Xiang Da Xiong , Yu Feng , Luo Hong , Yan Miao
Published: June 2021

Background: Meropenem is a carbapenem antibiotic that has demonstrated excellent in vitro activity against gram-negative clinical isolates and is commonly used in critically ill patients. This study aimed to find the pharmacokinetic/ pharmacodynamic of meropenem in critically ill patients and whether prolonged injection duration is really beneficial to meropenem therapy. Method: We included 209 samples in 64 patients in this prospective study. PPK analysis and Monte Carlo dosing simulations were developed using Phoenix.Results: A two-compartment model described the data adequately. Clearance (CL), volume (V), clearance of peripheral compartment (CL2), volume of peripheral compartment (V2) were 6.15 L/h, 2.83 L/h, 17.40L, and 17.48L, respectively. Creatinine clearance and uric acid were significant covariates. Patients with creatinine clearance of 60 ml/min or less and uric acid greater than 400 μmol/l could achieve the target > 90% under the minimum inhibitory concentration (MIC) of 8 mg/L, even with the administration dose of 500 mg/8 h with a 2-h infusion. Prolonging the infusion time significantly improved the therapeutic effect when MIC＜4. However, for the pharmacodynamic (PD) effects of 100% fT > MIC and 100% fT > 4MIC, no significant statistical difference was observed in critically ill patients.Conclusions: Critically ill patients with lower creatinine clearance and higher uric acid levels were likely to need a lower dosage of meropenem. Prolonged infusion time were not always beneficial for those who need a higher therapeutic target (100% fT > MIC,100% fT > 4 MIC) or with MIC 4mg/L. Increasing dose or alternative therapeutic strategies may be required for critically ill patients with drug-resistant or severe infections. The study is of great significance to guide the rational use of meropenem in critically ill patients.Trial registration: The trial was registered in the China Clinical Trial (ChiCTR1900020672). Registered on 12 January 2019.
One-step Green Synthesis of Eco-friendly Novel N-P Synergistic Flame Retardant for Cotton Fabric
Authors: Zhang Fengxiu , Liao Ying , Chen Yu , Lu Yi , Wan Caiyan , Zhang Guangxian
Published: June 2021

A novel N-P ammonium salt 1,3-propylene glycol diphosphate ester (APGDPE) flame retardant was tersely synthesized under solvent-free condition to lower cotton fabric fire hazard. The APGDPE structure was characterized by 1H NMR,13C NMR,31P NMR and IR spectroscopy. The reactive P=O(NH4+)2 and PO(OH)2 groups of APGDPE were successfully grafted into cotton fabric to form P-O-C covalent bond. The limiting oxygen indexes (LOI) of 20%, 30% and 40% APGDPE treated cotton reach 40-44.5%. After 50 laundering cycles (LCs), the LOI value of 40% treated cotton still maintains 27.3%. These results verified that the treated cotton has obtained outstanding flame retardancy and prominent durability. TG test indicates that the thermal stability and thermal oxidative stability of treated cotton are much higher than those of control cotton. TG-IR test displayed that treated cotton released less flammable volatile gases than those of control cotton. Cone calorimetry revealed that the PHRR and THR values of treated cotton decreased by 5.57 % and 26.8%,respectively. XRD results suggest that the crystallization zone of cotton fabric before and after treatment hardly change. TG-IR and cone calorimetry tests verified the APGDPE condensation phase mechanism for treated cotton.
Effects of Family-Based Dignity Intervention And Expressive Writing On Anticipatory Grief of Family Caregivers of Patient With Cancer: A Study Protocol For A Mixed Methods Study
Authors: Seyedfatemi Naima , Ghezeljeh Tahereh Najafi , Bolhari Jafar , Rezaei Masoud
Published: June 2021

Background: Family caregivers of dying cancer patients are affected by grief experiences and bereavement complications. Several approaches such as psycho-emotional care and an increase in spirituality have been suggested to diminish these complications. However, no study has examined the effects of family-based dignity intervention and expressive writing on anticipatory grief in family caregivers of dying cancer patients. This study was done to describe the protocol of a mixed-methods study on the effects of family-based dignity intervention and expressive writing on anticipatory grief in family caregivers of dying cancer patients.Methods: This mixed-methods study will be done in an embedded explanatory design with two quantitative and qualitative phases. In the first phase (quantitative), a randomized clinical trial will be done, in which 200 family caregivers of dying cancer patients will be randomly assigned to one of the four groups: family-based dignity intervention (group 1), expressive writing intervention (group 2), combined family-based dignity intervention and expressive writing (group 3), and controls (group 4). At baseline, one week and two weeks after the interventions, anticipatory grief will be assessed by a 13-item anticipatory grief scale. After the quantitative phase, the qualitative phase will be conducted through the conventional content analysis approach of Granheim and Lundman, in which an individual semi-structured interview will be taken from participants in the first phase to collect data on their experiences on interventions. Finally, data from quantitative and qualitative phases will be analyzed and discussed.Discussion: Family caregivers of dying cancer patients usually experience depression, anxiety, and psychological distress due to isolation and inadequate social support. Psychological interventions such as dignity and expressive writing interventions may help caregivers to obtain a better understanding of themselves and to increase their abilities to cope with caregiving difficulties. Therefore, there is a need for a comprehensive study confirming the effects of mentioned interventions on family caregivers of dying cancer patients. Trial registration: Iranian Registry of Clinical Trials (www.irct.ir) IRCT20210111050010N1. Retrospectively registered 6 February 2021.
Increased risk of chronic fatigue and hair loss following COVID-19 in individuals with hypohidrotic ectodermal dysplasia
Authors: Hennig Verena , Schuh Wolfgang , Neubert Antje , Mielenz Dirk , Jäck Hans-Martin , Schneider Holm
Published: June 2021

Background

Hypohidrotic ectodermal dysplasia (HED) is a group of genodermatoses in which deficient ectodysplasin A signalling leads to maldevelopment of skin appendages, various eccrine glands, and teeth. Individuals with HED often have disrupted epithelial barriers and, therefore, were suspected to be more susceptible to coronavirus infection.
Methods

56 households with at least one member who had coronavirus disease of 2019 (COVID-19) were enrolled in a longitudinal study to compare the course of illness, immune responses, and long-term consequences of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection in HED patients (n = 15, age 9–52 years) and control subjects of the same age group (n = 149).
Results

In 14 HED patients, mild or moderate typical COVID-19 symptoms were observed that lasted for 4–45 days. Fever during the first days sometimes required external cooling measures. The course of COVID-19 was similar to that in control subjects if patients developed antibodies blocking the SARS-CoV-2 spike protein. Five out of six HED patients with completely abrogated ectodysplasin A signalling (83%) suffered from chronic, in two cases very severe fatigue following COVID-19, while only 25% of HED patients with residual activity of this pathway and 21% of control subjects recovering from COVID-19 experienced postinfectious fatigue. Hair loss after COVID-19 was also more frequent among HED patients (64%) than in the control group (13%).
Conclusions

HED appears to be associated with an increased risk of long-term consequences of a SARS-CoV-2 infection. Preventive vaccination against COVID-19 should be recommended for individuals affected by this rare genetic disorder.
Biocatalytic synthesis of non-standard amino acids by a decarboxylative aldol reaction
Authors: Buller Andrew , Ellis Jonathan , Campbell Meghan , Kumar Prasanth , Geunes Eric , Bingman Craig
Published: June 2021

Enzymes are renowned for their catalytic efficiency and selectivity, but relatively few carbon-carbon bond forming enzymes have found their way into the biocatalysis toolbox. While engineering can overcome the challenges associated with C-C bond formation for some enzyme systems, the broader synthetic potential of biocatalysis is hindered by the lack of high-quality C-C bond forming transformations. Here we show that the enzyme UstD performs a highly selective decarboxylative aldol addition with diverse aldehyde substrates to make non-standard, γ-hydroxy amino acids. We increased the activity of UstD through three rounds of classic directed evolution and an additional round of computationally-guided engineering. The enzyme that emerged, UstD2.0, is efficient in a whole-cell biocatalysis format, which circumvents the need for enzyme purification, thereby facilitating its use in traditional organic settings. This new, highly stereoselective enzyme represents a unique expansion of the biosynthetic toolbox. The products are highly desirable, functionally rich bioactive γ-hydroxy amino acids that we demonstrate can be prepared stereoselectively on gram-scale. The X-ray crystal structure of UstD2.0 at 2.25 Å reveals the active site and the molecular basis for the remarkably promiscuity of this catalyst. Taking inspiration from the versatile reactivity of enamines in organic synthesis, we hypothesize that the enamine intermediate of UstD can be engineered to react with electrophiles other than aldehydes. The advent of structural information enabled by engineering of UstD2.0 provides a foundation for probing the unique mechanism of UstD and will guide efforts to expand the reactivity of this unique enzyme.
Sagittal imbalance of the spine is associated with poor sitting posture among primary and secondary school students in China: A cross-sectional study
Authors: Chaoqun Li , Yuqi Zhao , Zhenghui Yu , Xu Han , Li Wen , Xiang Lin
Published: June 2021

Background

There's no definite answer as to how writing posture affects students' spine. This study attempted to compare the sagittal curvature of the spine between sitting and standing postures in adolescents. To reveal the variation rule of spinal sagittal curvature of students with learning posture, and to discover the key factors that may affect students' spinal health.
Methods

1138 participants (male, 604; female, 534; age range, 6–18 y) from three schools in Tianjin, China, including 570 primary school students and 568 secondary school students. This study used SpineScan and PA200 Station Posture Assessment System to assess the sagittal curvature of the spine for three postures: sitting on a chair in an upright position, seated at a desk while reading/writing, and standing in a natural relaxed position. Analyze the difference of the spine angle of the three postures and the correlation between the sagittal plane angle of the spine and body posture.
Results

When some teenagers sat reading/writing, the sagittal angle of the spine markedly changed, with the lumbar lordosis angle significantly decreased (p < 0.05) and the thoracic kyphosis angle significantly increased (p < 0.05). These angles interact with each other and were positively correlated with the height of the teenager (R2 = 0.179; p < 0.05). By contrast, teenagers with lumbar lordosis and thoracic kyphosis angles within standard references ranges in a seated reading/writing posture also had good spine shape while standing.
Conclusions

Compared with standing posture, the angle of thoracic kyphosis gradually increases from upright sitting to reading/writing., Lumbar lordosis significantly decreasing or even disappearing, and the flexion of whole spine will increase the risk of spinal injury. Height is an important factor affecting the shape of students' sitting spine.
Subsidence Characteristics Study on the Highway and Substrata Overlying Acute Inclined Shallow Mined-out Area Under Different Mining Heights and Mining Angles
Authors: Bao Weixing , Wang Haibo , Lai Hongpeng , Zhao Zifeng , Liang Bangwei , Huang Yong , Ma Zhiwei
Published: June 2021

Based on an actual highway project traversing an acute inclined shallow mined-out area in Urumqi, China, a scale physical model experiment and numerical simulation method were adopted to study the stability and settlement mechanism of the highway subgrade and substrata overlying an acute inclined mined-out area under different mining heights and mining angles. Plastic pneumatic capsules with different shapes were embedded in similar strata made from clay, fine sand, and Vaseline to simulate the mined-out cavity. The capsule was removed to simulate the process of mining, and five cases with different mining heights and angles were studied. According to similarity theory, a physical model was established with a geometric similarity coefficient of 50 of the actual prototype, whereas the numerical model adopted the full-scale value. The physical model experiments and numerical simulations show that the settlement of the subgrade and substrata overlying the mined-out area is directly proportional to the mining height but inversely proportional to the mining angle. According to the settlement contour obtained by numerical simulations, which were in accordance with the physical model experiment results, two parameters, the free slip volume and the free surface, were defined to assess the stability of the subgrade and substrata overlying the mined-out area. The free slip volume and free surface calculation results demonstrate a strong relationship between the settlement and free slip volume and free surface. Therefore, the values of free slip volume and free surface could be reliable reference parameters to evaluate the stability of the subgrade and substrata overlying mined-out areas.
Expression of Efflux Pumps, Porins and Genotypic Insight Into the Carbapenem Resistance in Acinetobacter Baumannii
Authors: Hasani Alka , vahhabi Abolfazl , Rezaee Mohammad Ahangarzadeh , Baradaran Behzad , Hasani Akbar , Kafil Hossein Samadi , Abbaszadeh Faeze
Published: June 2021

Background.

The emergence of multidrug and extensive drug resistant strains of Acinetobacter baumannii‎ is a multifactorial consequence. Carbapenems, once considered the traditional standard of care for Acinetobacter infections however, are gradually being curtailed from the therapeutic regime due to the emergence of Carbapenem resistant Acinetobacter baumannii‎ (CRAB). Several carbapenem resistant mechanisms have been postulated for the rise of CRAB. This study investigated clinical A.baumannii isolates for the presence and level of expression of enzymatic and non-enzymatic genes, putatively associated with carbapenem resistance and their association with sequence typing.
Methods.

Uniplex, and Multiplex PCR were performed to identify the presence of oxacillinase (OXA) and metallo β-lactamase (MBLs) genes respectively. The level of expression of efflux pumps (adeB and adeJ) and porins (carO, omp33-36 and oprD) was investigated by Real-time PCR.
Results.

Of the 112 isolates obtained during this study, 100% were multidrug-resistant and 48.2% were extensive drug-resistant A.baumannii. All CRAB isolates harbored blaOXA−51−like, while, 82.1% and 63.4% of these isolates carried blaOXA−23−like and blaOXA−24/40−like genes, respectively. In contrast, the frequency of metallo β-lactamase genes was comparatively less than the oxacillinase genes. Over-expression of adeB and adeJ was observed in 66% and 42.8% A.baumannii strains respectively, while, decreased expression of carO, omp33-36 and oprD was observed in 75%, 66% and 72.3% strains respectively.
Conclusion.

Consistent with that reported by others, our study highlights the significant dissemination of the oxacillinase, blaOXA−23−like in CRAB isolates, particularly the simultaneous occurrence of blaOXA−23−like with blaOXA−40. Interestingly, while changes in the expression of efflux pumps and porins were observed nevertheless, more in depth investigation is required to decipher their contribution to carbapenem resistance in these strains.
Optimizing a Bayesian Hierarchical Adaptive Platform Trial Design for Stroke Patients
Authors: Gao Guangyi , Gajewski Byron J , Wick Jo , Beall Jonathan , Saver Jeffrey L , Meinzer Caitlyn
Published: June 2021

Background: Platform trials are well-known for their ability to investigate multiple arms on heterogeneous patient populations and their flexibility to add/drop treatment arms due to efficacy/lack of efficacy. Because of their complexity, it is important to develop highly optimized, transparent, and rigorous designs that are cost-efficient, offer high statistical power, maximize patient benefit and are robust to changes over time. Methods: To address these needs, we present a Bayesian platform trial design based on a Beta-Binomial model for binary outcomes that uses three key strategies: 1) Hierarchical modelling of subgroups within treatment arms that allows for borrowing of information across subgroups, 2) utilization of response-adaptive randomization (RAR) schemes that seek a tradeoff between statistical power and patient benefit, and 3) adjustment for potential drift over time. Motivated by a proposed clinical trial that aims to find the appropriate treatment for different subgroup populations of ischemic stroke patients, extensive simulation studies were performed to validate the approach, compare different allocation rules and study the model operating characteristics.Results & Conclusions: Our proposed approach achieved high statistical power, good patient benefit and was also robust against population drift over time. Our design provided a nice balance between the strengths of both the traditional RAR scheme and fixed 1:1 allocation and may be a promising choice for dichotomous outcomes trials investigating multiple subgroups.
Seasonal Geochemical Trends and Pollution Assessment of Bottom Sediments in the São Francisco Hydrographic Basin, Brazil: The Três Marias Reservoir
Authors: Lima Gustavo Filemon Costa , Bento Ciro Couto , Horn Adolf Heinrich , Marques Eduardo Duarte , Filho Hernando Baggio
Published: June 2021

The Três Marias Reservoir is the ninth-largest reservoir in Brazil, becoming crucial for national strategic development. However, many anthropic activities may affect the sediment quality, promoting the need for a proper environmental assessment. This research appraised the seasonal influences on the Três Marias Reservoir's sediments geochemistry, elucidating possible anthropogenic impacts. The concentrations of Mg, Al, Ca, Cr, Fe, Co, Cu, Cd, Ti, Mn, Ni, Zn, Ba, Pb, and Organic matter were measured in 78 samples of bottom sediments regarding the two seasons of the area, a dry winter and rainy summer. The Median ± 2 MAD (Median Absolute Deviation) settled the geochemical background for the two seasons. The sediment quality guidelines CONAMA 344/12 highlight the possible adverse ecological effects of pollutants. Hierarchical Clustering Analysis, Geoaccumulation index, and the Pollution Load Index delineated the polluted zones. The Pollution Load Index ranges from 0.25 to 2.28 in the dry season and 0.56 to 2.11 in the rainy season, defining three affected zones in the reservoir. Forestry and agriculture are the probable pollution sources, reaching warning levels that should be considered in further environmental strategies.
Effects of Interlayer Spacing and Oxidation Degree of Graphene Oxide Nanosheets on Water Permeation: A Molecular Dynamics Study
Authors: tan qiong , Fan Yan , Song Zailing , Chen Junlang , Chen Liang
Published: June 2021

Graphene oxide (GO) membranes have shown great potential in the applications of water filtration and desalination. The flow behavior and structural properties of water molecules through GO nanochannels are still under debate. In this work, molecular dynamics simulations were performed to explore the effects of interlayer spacing and oxidation degree of GO nanochannels on water transport. The results show that GO nanosheets has strong adsorption capacity. The adsorbed layer of water molecules on GO surface is thermodynamically stable and not easy to flow. When the interlayer spacing falls into the range of 0.6~1.0 nm, water molecules form into single or double adsorbed layers between two GO nanosheets. When the interlayer spacing is bigger than 1.2 nm, the other water layers in the middle of nanochannel become disordered. Taking the separation performance based on size exclusion into consideration, the most suitable interlayer spacing for water nanofiltration is 1.2 nm, which has one flowing layer of water molecules. Oxygen-containing groups are unfavorable for water permeation, as more and more hydrogen bonds prevent water flowing on GO surface with the increasing oxidation degree. Our simulation results may help to improve the design of GO nanofiltration membranes for water treatment.
Genome-wide association analysis reveal the genetic reasons affect melanin spot accumulation in beak skin of ducks
Authors: Liu Hehe , Wang Jianmei , Hu Jian , Wang Lei , Guo Zhanbao , Fan Wenlei , Xu Yaxi , Liu Dapeng , Zhang Yunsheng , Xie Ming , Tang Jing , Huang Wei , Zhang Qi , Zhou Zhengkui , Hou Shuisheng
Published: June 2021

Background
Skin pigmentation is a broadly appearing phenomenon of most animals and humans in nature. Here we used a bird model to investigate why melanin spot deposits on the skin.
Results
We result shown that melanin deposition in bird skin was induced by growth age and ultraviolet UV radiation and determined by genetic factors. GWAS helped us to identify two major loci affecting melanin deposition, located on chromosomes 13 and 25, respectively. Fine mapping works narrowed the candidate regions to 0.98 Mb and 1.0 Mb on chromosome 13 and 25, respectively. The MITF and POU2F3 may be the causative genes and synergistically affect melanin deposition during duck skin. Furthermore, our data strongly demonstrated that the pathway of melanin metabolism contributes to melanin deposition on the skin.
Conclusions
We demonstrated that age and UV radiation induce melanin deposition in bird skin, while heredity is the fundamental factor. The MITF and POU2F3 likely played a synergistic effect on the regulation of melanin synthesis, and their mutations contribute to phenotypic differences in beak melanin deposition among individuals. It is pointed out that melanin deposition in the skin is related to the pathway of melanin metabolism, which provided insights into the molecular regulatory mechanisms and the genetic improvement of the melanin deposition in duck beak.
Using Unique ORFan Genes as Strain-specific Identifiers for Escherichia Coli
Authors: Ferrandis-Vila Marta , Tiwari Sumeet K. , Mamerow Svenja , Semmler Torsten , Menge Christian , Berens Christian
Published: June 2021

BackgroundBacterial identification at the strain level is a much-needed, but arduous and challenging task. This study aimed to develop a method for identifying and differentiating individual strains among multiple strains of the same bacterial species. The set used for testing the method consisted of 17 Escherichia coli strains picked from a collection of strains isolated in Germany, Spain, the United Kingdom and Vietnam from humans, cattle, swine, wild boars, and chickens. We targeted unique or rare ORFan genes to address the problem of selective and specific strain identification. These ORFan genes, exclusive to each strain, served as templates for developing strain-specific primers.ResultsMost of the strains to be deployed experimentally (14 out of 17) possessed unique ORFan genes that were used to develop strain-specific primers. The remaining three strains were identified by combining a PCR for a rare gene with a selection step for isolating the experimental strains. Multiplex PCR allowed the successful identification of the strains both in vitro in spiked faecal material in addition to in vivo after experimental infections of pigs and recovery of bacteria from faecal material. In addition, primers for qPCR were also developed and quantitative readout from faecal samples after experimental infection was also possible.ConclusionsThe method described in this manuscript using strain-specific unique genes to identify single strains in a mixture of strains proved itself efficient and reliable in detecting and following individual strains both in vitro and in vivo, representing a fast and inexpensive alternative to more costly methods.
Biosynthesis and Characterization of Silver Nanoparticles produced by Phormidium ambiguum and Desertifilum tharense
Authors: Hanna Amira Lotfy , Hamouda Hayam , Goda Hanan , Elsayed Tarek , Sadik Mahmoud
Published: June 2021

The world faces a challenge with pervasion of multidrug resistant bacteria which encouraged the scientists to develop and discover alternative ecofriendly and easy to produce new antibacterial agents. Two Egyptian cyanobacteria were isolated and identified according to 16S rRNA gene sequencing as Phormidium ambiguum and Desertifilum tharense . The sequences were deposited in the GenBank with accession numbers of MW762709 and MW762710 for Desertifilum tharense and Phormidium ambiguum, respectively. These isolates have the ability to produce silver nanoparticles (Ag-NPs) extra- and intracellularly under light and dark conditions. The results of UV-Vis analysis showed promising extracellular Ag-NPs synthesis by Desertifilum tharense and Phormidium ambiguum under light conditions. Therefore, these Ag-NPs were characterized and evaluated for antibacterial and antioxidant activity. TEM, SEM and XRD analyses revealed the spherical crystals with face-centered cubic structures and size range of 6.24–11.4 nm and 6.46–12.2 nm for Ag-NPs of Desertifilum tharense and Phormidium ambiguum , respectively. XRD and EDX results clearly confirmed the successful synthesis of Ag-NPs in its oxide form or chloride form. The FTIR spectrum data confirmed the presence of hydroxyl and amide groups. Desertifilum tharense Ag-NPs displayed the largest inhibition zone ranged from 9 mm against Micrococcus luteus ATCC 10240 to 25 mm against methicillin resistant S. aureus (MRSA) ATCC 43300. For Phormidium ambiguum Ag-NPs, the inhibition zone diameter was in a range of 9–18 mm. The Ag-NPs of Phormidium ambiguum exhibited the highest scavenging activity of 48.7% comparing with that of Desertifilum tharense which displayed 43.753%.
Axillary Ultrasound and Fine-Needle Aspiration Cytology to Predict Clinically Relevant Nodal Burden in Breast Cancer Patients .
Authors: Carlotti Isabela , Reis Francisco José Candido dos , de Andrade Jurandyr Moreira , Rodrigues Tamara , Borba Jessica , Netto Amanda Homse , Polydoro Marina , Tiezzi Daniel Guimarães
Published: June 2021

BackgroundAxillary lymph node involvement is one important prognostic factor in breast cancer, but the way to access this information has modified over the years.This study evaluated if axillary ultrasound (US) coupled with fine needle aspiration cytology (FNAC) can better predict clinically relevant node metastasis than physical exam, in patients with breast cancer.MethodsThis is a cross-sectional study with retrospective data collection of 241 women with operable breast cancer who were submitted to preoperative axillary assessment by physical exam, US and FNAC if suspicious nodes by imaging. We calculated sensitivity, specificity, and accuracy of the methods. We compared the patient's characteristics using chi-square test, parametrics and non parametrics statistics according to the variable.ResultsThe most sensible method was US (0.59; 95% CI, 0.50-0.69) and the most specific was US coupled with FNAC (0.97; 95% CI, 0.92-0.99 ). Only 2,7% of the patients with normal axillary US had more than 2 metastatic nodes in the axillary lymph node dissection, against 50% of the patients with suspicious lymph nodes in the US and positive FNAC. ConclusionsWe found that axillary US and FNAC are more accurate than physical examination in detecting node metastasis in breast cancer patients. Moreover, axillary US coupled with FNAC can sort patients that have a few metastatic nodes at most from those with heavy axillary burden and could be one more tool to initially evaluate patients and define treatment´s strategies.
Dimethyl Fumarate Ameliorates Lipopolysaccharide-induced Acute Lung Injury by Inhibiting NLRP3 Inflammasome-mediated Pyroptosis
Authors: Li Huayu , Li Mengyan , Dong Chao , Liu Bing
Published: June 2021

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are clinically severe respiratory disorders, and there are currently no Food and Drug Administration-approved drug therapies. It is established that Dimethyl fumarate (DMF) exhibits anti inflammatory effects, however, the specific effect of DMF on ALI remains largely unknown. The aim of the present study was to investigate whether, and by which mechanism, DMF alleviated lipopolysaccharide (LPS)-induced ALI. We found that intraperitoneal injection of DMF markedly reduced the pulmonary injury, decreased pulmonary edema and pulmonary permeability. Emerging studies suggested that the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome-mediated pyroptosis played a critical role during ALI. NLRP3 inflammasome-mediated pyroptosis is significantly activated with the cleavage of caspase-1 and GSDMD occurring in the lung of LPS-induced ALI. DMF inhibited the activation of the NLRP3 inflammasome and pyroptosis in both lung of ALI mice and LPS-induced BEAS-2B cells. Mechanistically, DMF enhanced expressions of Nuclear factor erythroid-2-related factor 2 (Nrf2), leading to inactivation of NLRP3 inflammasome and reduction of pyroptosis in both ALI mice and LPS-induced BEAS-2B cells. Conversely, Nrf2 inhibitor reduced the inhibitory effects of DMF on NLRP3 inflammasome and pyroptosis, and consequently blocked the improvement roles of DMF on ALI in mice. This study for the first time demonstrated that DMF could improve LPS-induced ALI via inhibiting NLRP3 inflammasome and pyroptosis, and that these effects were mediated by triggering Nrf2 expression, suggesting a therapeutic potential of DMF as an anti-inflammatory agent for ALI/ARDS treatment.
Acute Periprosthetic Infection After Total Knee Arthroplasty in Patients With Rheumatoid Arthritis Versus Osteoarthritis: a Population-based Study
Authors: Chung Ho-Ken , Wen Shu-Hui , Chang Wei-Chuan , Liu Kuan-Lin
Published: June 2021

Osteoarthritis is the main cause for total knee arthroplasty, followed by rheumatoid arthritis. Previous studies have reported conflicting results concerning the risk of periprosthetic infection after total knee arthroplasty for rheumatoid arthritis and osteoarthritis patients. Thus, this study aimed to examine whether rheumatoid arthritis patients had a higher risk of acute periprosthetic infection after total knee arthroplasty compared to osteoarthritis patients. We conducted a retrospective cohort study using Taiwan’s National Health Insurance Research Database of the whole population from 2012 to 2015, and collected the medical records of osteoarthritis patients or rheumatoid arthritis patients who underwent total knee arthroplasty. To evaluate the risk of acute periprosthetic infection in rheumatoid arthritis patients, propensity score matching was implemented for osteoarthritis patients. Acute periprosthetic infection was observed in 2.58% of total knee arthroplasty cases in rheumatoid arthritis patients and 2.66% of total knee arthroplasty cases in osteoarthritis patients. Rheumatoid arthritis and osteoarthritis patients had comparable risk for 90-day and one-year periprosthetic infection. In conclusion, patients with rheumatoid arthritis were not at higher risk of acute periprosthetic infection after total knee arthroplasty compared to osteoarthritis patients. The current treatment strategy for patients with rheumatoid arthritis undergoing total knee arthroplasty is safe and appropriate.
Circular Economy Strategy and Waste Management: A Bibliometric Analysis in Its Contribution To Sustainable Development, Towards A Post COVID-19 Era
Authors: Negrete-Cardoso Mariana , Rosano-Ortega Genoveva , Álvarez-Aros Erick Leobardo , Tavera-Cortés María Elena , Vega-Lebrún Carlos Arturo , Sánchez-Ruíz Francisco Javier
Published: June 2021

A descriptive analysis of 416 documents was performed using bibliometric techniques, in order to gather existing knowledge in circular economy (CE) focusing on waste management (2007–2020). The results of this study indicate that annual scientific production increased 94% in the last five years; highlighting the countries of Italy, Spain, United Kingdom, China, Brazil and India. The conceptual analysis indicates strong linkage between CE and sustainable production, waste management and recycling. Emerging research trends evolved from processes and industry oriented approach (2017), towards waste management, recycling and circular economy (2019) and sustainable development and urban solid waste (2020). Through intellectual analysis, schools of thought were identified, where the most influential authors such as Wang, Ghisellini, Zhang and the European Commission with the greatest connection with other authors stand out. Results found denote the challenge represented by the implementation of comprehensive policies in CE, in addition to measure its contribution to sustainable development. The above, being a key alternative for green recovery in response to current COVID-19 pandemic.
Significant Improvement of Straw Lignocellulose Degradation Rate by Subordination Consortium Composed of Cellulomonas ZJW-6 and Acinetobacter DA-25
Authors: Guan Yunpeng , Zhu Hongyu , Zhu Yuan , Shu Longhua , Zhao Hemei , Song Jian , Yang Xue , Wu Zhihai , Wu Lei , Yang Meiying
Published: June 2021

BackgroundThe effective utilization of lignocellulose is essential for achieving circular economy and sustainable agricultural development. The screening of lignocellulose-degrading strains from the environment and artificial establishment of microbial consortia can achieve better degradation effects. In this paper, microbial consortium 625 was established and screened based on high lignocellulose degradation ability but low β-glucosidase activity of Cellulomonas ZJW-6 to complement enzyme activity and enhance lignocellulose degradation by exerting the subordination effect. This research provides an effective strategy for artificially establishing microbial consortia, improving lignocellulose degradation efficiency, and enhancing bioenergy production.ResultsIn order to establish high-efficiency microbial consortia, Cellulomonas ZJW-6 with low β-glucosidase activity was combined in pairs with 14 strains with high β-glucosidase activity according to the enzyme activity complementation principle, from which microbial consortium 625 composed of strains ZJW-6 and DA-25 was screened, which had significantly enhanced lignocellulose degradation rate compared with purely cultured ZJW-6 strain and other 13 combinations. The single factor test showed that consortium 625 had better pH and temperature tolerance. The lignocellulose degradation rate of this consortium was 57.62% after verification test under optimized conditions using response surface method. The induction test showed that the growth of strain DA-25 was inhibited by strain ZJW-6 and its filtrate, while strain DA-25 and its filtrate promoted the growth of strain ZJW-6 and significantly enhanced the activities of key enzymes in the consortium 625 lignocellulose degrading system, among which the β-Glucosidase activity was significantly higher than that in purely cultured ZJW-6 strain. ConclusionMicrobial consortium 625, composed of Cellulomonas ZJW-6 (dominant strain) and Acinetobacter DA-25, with high lignocellulose degradation efficiency, was screened according to the enzyme activity complementation principle. Interestingly, microbial consortium 625 exhibited complementation in enzyme activities of its two strains, improvement in its tolerance to temperature and pH, and the same effect of DA-25 filtrate as strain DA-25. Based on the previous studies on Acinetobacter, we speculate that a certain compound adverse to the growth of strain DA-25 may be produced during lignocellulose degradation by strain ZJW-6, while secretions of strain DA-25 inhibit this compound leading to an increase in the growth and enzyme activity of strain ZJW-6.
Thermodynamic Simulation Modeling Analysis and Experimental Research of Vertical Ultrasonic Vibration Assisted EDM
Authors: Dong Yinghuai , Liu Jiajun , Li Guangyan , Wang Yan
Published: June 2021

Compared with traditional EDM, ultrasonic vibration assisted EDM ((UEDM)) shows better performance in machining efficiency and surface quality. But the material removal process of UEDM is complex, and there are many influencing factors, so it is difficult to describe the material removal process accurately. In this study, based on the voltage variation during UEDM processing and combined with the heat transfer theory, the material removal model of TC4 titanium alloy under the condition of single pulse vertical ultrasonic vibration UEDM was established, and the material removal process of UEDM under different amplitudes was analyzed. The machining efficiency and surface quality of UEDM with different ultrasonic energy under the condition of vertical ultrasonic vibration are obtained verified by UEDM experiments. The best ultrasonic energy under different current can be obtained by adjusting the current and ultrasonic vibration energy, which can improve the efficiency of UEDM.