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2021 ◽  
Author(s):  
Juan Ricardo Rocha ◽  
Renato Mello Prado ◽  
Marisa Cássia Piccolo

Abstract Climate change increases the occurrence of droughts, decreasing the production of tropical forages through the induction of physiological stress. Si is expected to broaden the limit from physiological stress of forages grown under water restriction, which may come from an improvement in the stoichiometric homeostasis of Si with N and C, favoring physiological aspects. This study assessed whether Si supply via fertigation improves physiological aspects and the water content in the plant by means of an antioxidant defense system and changes in the C:N:Si stoichiometry during the regrowth of two cultivars of Panicum maximum grown under two soil water regimes (70 and 40% of the soil’s water retention capacity). The forages studied are sensitive to water deficit without silicon supply. The application of Si via fertigation attenuated the water deficit, favoring plant growth by stabilizing the stoichiometric homeostasis C:N and C:Si, which are responsible for increasing the plant capacity of converting accumulated C in dry mass, favoring the water content of the plant tissue and the photosynthetic efficiency. This study highlights the importance of the physiological function of Si, and effects on the stoichiometry of C and N, which are neglected in most research on forages grown under water restriction.


2021 ◽  
Author(s):  
Neda Gholami ◽  
Abasalt Hosseinzadeh Colagar ◽  
Mohammad Hossein Sinkakarimi ◽  
Farshad Sohbatzadeh

Abstract The cold atmospheric pressure plasma jet (APPJ) is one of the effective tools with medical applications that its positive effects have been reported by various researchers, including sterilization of liquid and solid surfaces, treatment of chronic wounds, treatment of cancer tumors, and blood clots. This study investigated the effects of APPJ discharge on the two species of Earthworms (Aporrectodea trapezoides and Eisenia fetida). The APPJ discharge for different time durations, zero as a blank, 5, 10, 20, and 30 seconds, on these two species. Then some of these effects on the worms, including regeneration ability to miss segments, Malondialdehyde (MDA), catalase activity (CAT), total antioxidant capacity (TAC), cell death, total proteins, and protein profile in the coelomic fluid were investigated. Results showed levels of TAC and CAT increased after plasma treatment. In addition, a significant change was not observed in MDA levels and cell death. In summary, it can be concluded that APPJ exposure up to 40 seconds didn’t inhibit effects on the TAC levels of the earthworms and the defense system was able to fight oxidative stress and by increasing the expression of some proteins APPJ lead to better regeneration.


Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1864
Author(s):  
Isabel Pagani ◽  
Guido Poli ◽  
Elisa Vicenzi

Viral invasion of target cells triggers an immediate intracellular host defense system aimed at preventing further propagation of the virus. Viral genomes or early products of viral replication are sensed by a number of pattern recognition receptors, leading to the synthesis and production of type I interferons (IFNs) that, in turn, activate a cascade of IFN-stimulated genes (ISGs) with antiviral functions. Among these, several members of the tripartite motif (TRIM) family are antiviral executors. This article will focus, in particular, on TRIM22 as an example of a multitarget antiviral member of the TRIM family. The antiviral activities of TRIM22 against different DNA and RNA viruses, particularly human immunodeficiency virus type 1 (HIV-1) and influenza A virus (IAV), will be discussed. TRIM22 restriction of virus replication can involve either direct interaction of TRIM22 E3 ubiquitin ligase activity with viral proteins, or indirect protein–protein interactions resulting in control of viral gene transcription, but also epigenetic effects exerted at the chromatin level.


Antibiotics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 891
Author(s):  
Victoria Grimus ◽  
Débora C. Coraça-Huber ◽  
Stephan J. M. Steixner ◽  
Markus Nagl

Background: N-chlorotaurine (NCT), an antiseptic that originates from the human defense system, has broad-spectrum microbicidal activity and is well tolerated by human tissue and applicable to sensitive body regions. Bacteria in short-term biofilms, too, have been shown to be killed by NCT. It was the aim of the present study to demonstrate the activity of NCT against bacteria and yeasts in longer-lasting biofilms, including their co-culture. Materials and methods: Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella variicola biofilms were grown for 14 weeks in MBECTM inoculator with 96 well base. Some pegs were pinched off weekly and incubated in 1% NCT in PBS (PBS only for controls) at pH 7.1 and 37 °C, for 30 and 60 min. Subsequently, bacteria were resuspended by ultrasonication and subjected to quantitative cultures. Similar tests were conducted with C. albicans biofilms grown on metal (A2-steel) discs for 4 weeks. Mixed co-cultures of C. albicans plus each of the three bacterial strains on metal discs were grown for 5–7 weeks and weekly evaluated, as mentioned above. Results: Single biofilms of S. aureus, P. aeruginosa, and K. variicola grew to approximately 1 × 106 colony forming units (CFU)/mL and C. albicans to 1 × 105 CFU/mL. In combined biofilms, the CFU count was about 1 log10 lower. Viable counts of biofilms of single bacteria were reduced by 2.8 to 5.6 log10 in 1% NCT after 60 min (0.9 to 4.7 log10 after 30 min) with Gram-negative bacteria being more susceptible than S. aureus. Significant reduction of C. albicans by 2.0 to 2.9 log10 occurred after 4 h incubation. In combined biofilms, viable counts of C. albicans were reduced by 1.1 to 2.4 log10 after 4 h, while they reached the detection limit after 1 to 2 h with bacteria (2.0 to > 3.5 log10 reduction). Remarkably, older biofilms demonstrated no increase in resistance but constant susceptibility to NCT. This was valid for all tested pathogens. In electron microscopy, morphological differences between NCT-treated and non-treated biofilms could be found. Conclusions: NCT is active against long-term biofilms of up to several months irrespective of their age. Combined biofilm cultures of yeasts and bacteria show a similar susceptibility pattern to NCT as single ones. These results contribute to the explanation of the clinical efficacy of NCT, for instance, in infected chronic wounds and purulently coated crural ulcerations.


2021 ◽  
Vol 12 ◽  
Author(s):  
Saima Aslam ◽  
Nadia Gul ◽  
Mudasir A. Mir ◽  
Mohd. Asgher ◽  
Nadiah Al-Sulami ◽  
...  

Plant growth regulators have an important role in various developmental processes during the life cycle of plants. They are involved in abiotic stress responses and tolerance. They have very well-developed capabilities to sense the changes in their external milieu and initiate an appropriate signaling cascade that leads to the activation of plant defense mechanisms. The plant defense system activation causes build-up of plant defense hormones like jasmonic acid (JA) and antioxidant systems like glutathione (GSH). Moreover, calcium (Ca2+) transients are also seen during abiotic stress conditions depicting the role of Ca2+ in alleviating abiotic stress as well. Therefore, these growth regulators tend to control plant growth under varying abiotic stresses by regulating its oxidative defense and detoxification system. This review highlights the role of Jasmonates, Calcium, and glutathione in abiotic stress tolerance and activation of possible novel interlinked signaling cascade between them. Further, phyto-hormone crosstalk with jasmonates, calcium and glutathione under abiotic stress conditions followed by brief insights on omics approaches is also elucidated.


Author(s):  
Ian Lunsford ◽  
Thomas H Bradley

Aircraft survivability is a classical consideration of combat aircraft design and tactical development, but the fundamental model of aircraft survivability must be updated to be able to consider modern tactical scenarios that are applicable to unmanned aircraft. This paper seeks therefore to define the set of design tradeoffs and an evaluation of the tactical effectiveness for unmanned aircraft survivability. Traditional and modern survivability evaluation methods are presented and integrated into a computational simulation to create a probabilistic evaluation of unmanned aircraft survivability. The results demonstrate the development of design tradeoffs for a hypothetical unmanned C-130J Hercules against a single man-portable air defense system. The discussion focuses on the demonstration of the utility of this survivability evaluation framework for consideration of survivability in unmanned aerial vehicle (UAV) design, the utility of considering survivability in the design of multi-UAV configurations (including the loyal wingman and swarms), and the value of the probabilistic survivability model for multi-aircraft simulations.


2021 ◽  
Author(s):  
Muhammad Kaleem ◽  
Iqbal Hussain ◽  
Mansoor Hameed ◽  
Muhammad Sajid Aqeel Ahmad ◽  
Anam Mehmood ◽  
...  

Abstract Calcium (Ca) is a macronutrient and work as a modulator to mitigate oxidative stress induced by heavy metals. Present work was conducted to elucidate the role of Ca in modulating growth, physio-biochemical traits, and cellular antioxidant defense system in Zea mays L. seedlings under Cd stress. The experiment was designed in a complete randomized design with two levels of Cd (0 and 150 µM) and six levels of Ca (0, 0.5, 1, 2.5, 5 and 10 mM). Maize seedlings exposed to Cd at150 µM concentration showed a notable decrease in growth, biomass, anthocyanins, chlorophylls, and antioxidant enzymes activities. Higher level of Cd (150 µm) also caused an upsurge in oxidative damage observed as higher electrolyte leakage (increased membrane permeability), H2O2 production and MDA accumulation. Supplementation of Ca notably improved growth traits, photosynthetic pigments, cellular antioxidants (APX, POD and ascorbic acid), anthocyanins and level of osmolytes. The significant improvement in the osmolytes (proteins and amino acids), and enzymatic antioxidative defense system enhanced the membrane stability and mitigated the damaging effects of Cd. The present results concluded that exogenously applied Ca can potentially improve growth by regulating antioxidants and enable maize plants to withstand the Cd toxicity.


Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 682
Author(s):  
Yasmina K. Mahmoud ◽  
Ahmed A. Ali ◽  
Heba M. A. Abdelrazek ◽  
Tahany Saleh Aldayel ◽  
Mohamed M. Abdel-Daim ◽  
...  

The ameliorative effect of L-arginine (LA) and L-carnitine (LC) against fipronil (FPN)-induced neurotoxicity was explored. In this case, 36 adult male rats were randomly divided into six groups: group I received distilled water, group II received 500 mg/kg LA, group III received 100 mg/kg LC, group IV received 4.85 mg/kg FPN, group V received 4.85 mg/kg FPN and 500 mg/kg LA and group VI received 4.85 mg/kg FPN and 100 mg/kg LC for 6 weeks. Cognitive performance was assessed using Barnes maze (BM). Serum corticosterone, brain total antioxidant capacity (TAC), malondialdehyde (MDA) and dopamine were measured. Histopathology and immunohistochemistry of ionized calcium-binding adaptor (Iba-1), doublecortin (DCX) and serotonin (S-2A) receptors were performed. Fipronil induced noticeable deterioration in spatial learning and memory performance. In addition, FPN significantly (p < 0.05) diminished brain antioxidant defense system and dopamine coincide with elevated serum corticosterone level. Histopathological examination revealed degenerative and necrotic changes. Furthermore, Iba-1 and DCX were significantly expressed in cortex and hippocampus whereas S-2A receptors were significantly lowered in FPN group. However, administration of LA or LC alleviated FPN-induced deteriorations. In conclusion, LA and LC could be prospective candidates for mitigation of FPN-induced neurotoxicity via their antioxidant, anti-inflammatory and neuropotentiating effects.


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