Laboratory studies on the effect of gamma radiation on Erwinia amylovora survival on apple fruit

1986 ◽  
Vol 32 (10) ◽  
pp. 787-790 ◽  
Author(s):  
W. J. Janisiewicz ◽  
T. van der Zwet ◽  
P. B. Jahrling

Susceptibility of Erwinia amylovora to gamma irradiation was determined in vitro on test tube cultures and in vivo on apples and pears. Bacterial strains differed in susceptibility to irradiation. Higher doses of irradiation (ca. 80 krad (1 krad = 10 Gy)) were needed to kill the bacterium on fruit compared with test tube cultures (from 20 to more than 50 krad). Fruit with natural populations of E. amylovora collected from a severely blighted orchard, exposed to doses of 140 krad, still contained viable bacteria. Surviving E. amylovora were pathogenic to green 'Bartlett' pears. Five radiation-sensitizing chemicals (used previously against different pathogens on other commodities) were tested against E. amylovora. N-Ethylmaleimide sensitized the bacteium to gamma irradiation. Treatment of natural populations of the bacterium on apples with N-ethylmaleimide eliminated E. amylovora from the apple surface with a gamma irradiation dose one-third lower than the maximum rate tolerable by fruit.

2020 ◽  
Vol 18 (1) ◽  
pp. 764-777
Author(s):  
Sumaira Naz ◽  
Muhammad Zahoor ◽  
Muhammad Naveed Umar ◽  
Saad Alghamdi ◽  
Muhammad Umar Khayam Sahibzada ◽  
...  

AbstractThioureas and their derivatives are organosulfur compounds having applications in numerous fields such as organic synthesis and pharmaceutical industries. Symmetric thiourea derivatives were synthesized by the reaction of various anilines with CS2. The synthesized compounds were characterized using the UV-visible and nuclear magnetic resonance (NMR) spectroscopic techniques. The compounds were screened for in vitro inhibition of α-amylase, α-glucosidase, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes and for their antibacterial and antioxidant potentials. These compounds were fed to Swiss male albino mice to evaluate their toxicological effects and potential to inhibit glucose-6-phosphatase (G6Pase) inhibition. The antibacterial studies revealed that compound 4 was more active against the selected bacterial strains. Compound 1 was more active against 2,2-diphenyl-1-picrylhydrazyl and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals, AChE, BuChE, and α-glucosidase. Compound 2 was more potent against α-amylase and G6Pase. Toxicity studies showed that compound 4 is safe as it exerted no toxic effect on any of the hematological and biochemical parameters or on liver histology of the experimental animals at any studied dose rate. The synthesized compounds showed promising antibacterial and antioxidant potential and were very active (both in vitro and in vivo) against G6Pase and moderately active against the other selected enzymes used in this study.


2021 ◽  
Author(s):  
Yuchen Sun ◽  
Jizhao Wang ◽  
Xuanzi Sun ◽  
Jing Li ◽  
Xu Zhao ◽  
...  

Abstract Background Radioresistance, a poorly understood phenomenon, results in the failure of radiotherapy and consequent local recurrence, threatening a large proportion of ESCC patients. To date, lncRNAs have been found to be involved in diverse biological processes, including radioresistance.Methods ELISA was used to evaluated the H3 modifications in radio-resistant ESCC cells. FISH and qRT-PCR were adopted to examine the expression and localization of lncRNA-NORAD, pri-miR-199a and miR-199a. Electron microscopy and Nanoparticle tracking analysis (NTA) was conducted to observe and identify exosomes. High-throughput RNA sequencing and TMT mass spectrometry were performed to identify the functional lncRNAs and proteins involved in ESCC radioresistance. A series of in vitro and in vivo experiments were performed to investigate the biological effect of NORAD. CHIP, qPCR-RIP, co-IP and dual-luciferase reporter assays were used to explore the interaction of related RNAs and proteins. Results We show here that a DNA damage activated non-coding RNA-NORAD, which is critical for ESCC radio-resistance. NORAD was highly expressed in radio-resistant ESCC cells and tissues. Irradiation treatment promotes NORAD expression via enhancing H3K4me2 enrichment on its region. NORAD knockdown cells exhibit significantly hypersensitivity to irradiation in vivo and in vitro. NORAD is required for initiating repair and restart of stalled forks, G2 cycle arrest and homologous recombination repair upon irradiation treatment. Mechanistically, NORAD inhibits miR-199a expression by competitively binding PUM1 from pri-miR-199a, inhibiting the process of pri-miR-199a. Mature miR-199a in NORAD-knockdown cells can be packaged into exosomes; miR-199a restores the radiosensitivity of radioresistant cells by targeting EEPD1, then inhibiting ATR/Chk1 signaling pathway. Simultaneously, NORAD knockdown blocks the ubiquitination of PD-L1, leads to the better response for radiation and anti-PD-1 treatment in mouse model.Conclusion This study raises the possibility that LncRNA-NORAD could be a potential treatment target for improving the efficiency of immunotherapy in combination with radiation in ESCC.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Cheng-Chih Tsai ◽  
Sew-Fen Leu ◽  
Quan-Rong Huang ◽  
Lan-Chun Chou ◽  
Chun-Chih Huang

Three lactic acid bacterial strains,Lactobacillus plantarum, HK006, and HK109, andPediococcus pentosaceusPP31 exhibit probiotic potential as antiallergy agents, both in vitro and in vivo. However, the safety of these new strains requires evaluation when isolated from infant faeces or pickled cabbage. Multiple strains (HK006, HK109, and PP31) were subject to a bacterial reverse mutation assay and a short-term oral toxicity study. The powder product exhibited mutagenic potential inSalmonellaTyphimurium strains TA98 and TA1535 (with or without metabolic activation). In the short-term oral toxicity study, rats received a normal dosage of 390 mg/kg/d (approximately9×109 CFU/kg/d) or a high dosage of 1950 mg/kg/d (approximately4.5×1010 CFU/kg/d) for 28 d. No adverse effects were observed regarding the general condition, behaviour, growth, feed and water consumption, haematology, clinical chemistry indices, organ weights, or histopathologic analysis of the rats. These studies have demonstrated that the consumption of multiple bacterial strains is not associated with any signs of mutagenicity ofS.Typhimurium or toxicity in Wistar rats, even after consuming large quantities of bacteria.


2016 ◽  
pp. 85-92 ◽  
Author(s):  
R. Haidar ◽  
C. Calvo-Garrido ◽  
J. Roudet ◽  
T. Gautier ◽  
A. Deschamps ◽  
...  

Author(s):  
Prasanna Habbu ◽  
Vijayanand Warad ◽  
Rajesh Shastri ◽  
Chetan Savant ◽  
Smita Madagundi ◽  
...  

Author(s):  
KAMNI RAJPUT ◽  
RAMESH CHANDRA DUBEY

Objective: In vitro antioxidant activity, in vivo antidiabetic property and intestinal attachment by two potential probiotic bacterial strains, namely, Enterococcus faecium and Enterococcus hirae were studied using albino rats. Methods: Antioxidant the activity was assessed using 2,2-Diphenyl-1-picrylhydrazyl radicals scavenging assay. Alloxan was administered intraperitoneally to induce diabetic conditions in experimental rats. Animals were treated with oral administration of Enterococcus spp., such as E. faecium, and E. hirae isolated from goat and sheep milk. The control animal group received normal saline for the same days. Glibenclamide drug was used as a positive control against probiotic bacterial cells. Results: However, administration of probiotic bacterial strains E. faecium and E. hirae, in albino rats significantly (p<0.05) at varying doses lowered blood glucose levels in diabetic rats as compared to the diabetic control group. Both the species of Enterococcus increased the bodyweight of experimental rats. However, E. faecium was the best antidiabetic strain having the antioxidant activities also in comparison to E. hirae. The attachment of probiotic bacterial cells E. faecium on the rat’s intestine wall against pathogens was examined. Furthermore, E. faecium showed its aggregation with pathogens by attachment of the intestines of albino rats. This showed that both the bacterial strains exhibited in vivo antidiabetic effect. Conclusion: The results of this study showed that probiotic bacteria possess antioxidant, antidiabetic activities, and attachment of intestine.


2021 ◽  
Author(s):  
Reinier Gesto-Borroto ◽  
Gabriela Meneses ◽  
Alejandro Espinosa-Cerón ◽  
Guillermo Granados ◽  
Jacquelynne Cervantes-Torres ◽  
...  

Abstract The genus Galphimia is widely distributed in Mexico, and is represented by 22 species, including medicinal species. The sedative and anti-inflammatory effects of galphimines produced by the species Galphimia glauca have been documented. Formerly, molecular studies using DNA barcodes demonstrated that nine populations botanically classified as Galphimia glauca belong to four different species of the genus Galphimia, and that only one exhibited the sedative properties; however, all the collected species showed anti-inflammatory activity. Other bioactive compounds like quercetin, galphins, galphimidins and glaucacetalins have been identified from methanolic extracts of plants botanically classified as Galphimia glauca. The aim of this work was to determine the anti-inflammatory activity of methanolic extracts of nine collected Galphimia spp. populations grown in Mexico. The possible modes of action were analyzed by evaluating the inhibition of LPS-induced inflammation processes both in vitro and in vivo. The nine populations were evaluated by an in vitro model using RAW 264.7 murine macrophage cells, and two populations (a galphimine-producing and a non-galphimine-producing population) were selected for the in vivo experiments of systemic inflammation and neuroinflammation in mice. Results suggest that an anti-inflammatory in vitro effect was present in all the studied populations, evidenced by the inhibition of nitrite production. An inhibitory systemic inflammation in mice was exerted by the two analyzed populations. In the neuroinflammation model, the anti-inflammatory effect was demonstrated in methanolic extract of the non-galphimine-producing population. For the populations of Galphimia spp. studied herein, the anti-inflammatory effect could not be correlated to the presence of galphimines.


1991 ◽  
Vol 69 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Lawrence L. Spriet

Anaerobic energy production is essential for the production of muscular tension when the demand for energy is greater than can be provided aerobically and when oxygen is in short supply. The largest source of anaerobic energy is from the glycolytic pathway. With sustained tetanic contractions, muscle glycolytic activity is high and hydrogen ions (H+) accumulate while tension production decreases. The increasing [H+] and decreasing tension led to the suggestion that H+ inhibits the activity of the regulatory glycolytic enzyme phosphofructokinase (PFK). Early in vitro work confirmed the H+ sensitivity of PFK in the test tube, indicating that little PFK activity should persist at a pH of 6.9–7.0. However, in situ and in vivo experiments suggested that significant PFK activity was maintained during intense contractions when muscle pH decreased to 6.4–6.6. There are several concerns associated with the application of in vitro findings to in vivo exercise situations: (i) there is little in vitro work in mammalian skeletal muscle with substrate and modulator concentrations representative of exercise, (ii) most in vitro analyses of PFK activity are performed following the dilution of the enzyme in mediums with low protein concentration, and (iii) do the modulators identified in vitro exist in high enough in vivo concentrations at rest and during exercise to contribute to the regulation of PFK? More recent in vitro and in situ PFK experiments have overcome some of these concerns. They confirm that during intense, short-term tetanic contractions, PFK activity is well matched to the ATP demand despite decreases in pH to ~6.4–6.5. A combination of decreased inhibitor (ATP) and increased substrate (fructose 6-phosphate) contents coupled with increases in the contents of several positive modulators may be responsible for the maintained PFK activity. This combination reduces the pH-dependent ATP inhibition of PFK and extends the physiological pH range of the enzyme to the range normally measured during this type of muscular activity.Key words: glycolysis, phosphofructokinase, anaerobic metabolism, acidosis.


Author(s):  
O. O. Timina ◽  
L. G. Ionova ◽  
O. Y. Timin

The ontogenetic states of T. biebersteiniana in the broad interpretation which grows in Transdnistria was refined. In the tract of Kalagur-Stroentsy four age states were defined, on limestone faults along the valley of the Dniester - five. A comparative study of the main demographic indicators of mesophilic and xerophilous ecological groups of T. biebersteiniana has been conducted. The morphometric indicators of the populations of both ecogroups have been identified and analyzed: total population density, ontogenetic spectrum, projective cover, and age and efficathy indices. The method of propagation of mesophilic and xerophilous ecogroups representatives has been clarified. Mesophilic plants propagated vegetatively, the forming bulbs have a sporophyte origin, and the mature mesophilic populations are renewed homophasically. Xerophilous plants reproduce mainly sexually; the reproduction of developing populations is mainly heterophasic. Both ecogroups were rejuvenated, so their resistance as the survival in phytocenosis was unified by the comparable reproduction and replacement indices. The surveyed mesophilic and xerophilous populations were classified as young, left-handed, normal, and incomplete. Populations of both ecogroups, being young, with high reproduction and replacement indices, were not affected by the tulip breaking virus, and were relatively resistant and adapted to their biotope. Prospects for their continued existence now are quite favorable in the absence of sudden and sharp effects on them of possible biotic and abiotic stressors. There is a low net reproduction in the plants of the mesophilic group in natural populations. The inducing of additional micro bulbs in the culture of in vitro based on indirect somatic embryogenesis is promising to increase T. biebersteiniana propagation rate.


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