Gamma Radiation Sensitivity of Listeria monocytogenes

Seven strains of Listeria monocytogenes were irradiated in culture media or in mechanically deboned chicken meat. The survivor plots were quadratic curves when cultures were in the log phase of growth or when they were irradiated in chicken meat; cultures in the senescent phase of growth showed linear responses to irradiation. Cultures from cells surviving an irradiation dose of 1.5 kGy were no more radiation resistant that those which had had no previous exposure to irradiation. Cultures centrifuged and resuspended in water were more sensitive to radiation than those resuspended in solutions containing organic materials. These studies indicated that a dose of 2 kGy was sufficient to destroy 1 × 104 cells of L. monocytogenes.

Download Full-text

GAMMA RADIATION SENSITIVITY OF THE SPIDER BEETLE, GIBBIUM PSYLLOIDES (COLEOPTERA: PTINIDAE)

The Canadian Entomologist ◽

10.4039/ent1041551-10 ◽

1972 ◽

Vol 104 (10) ◽

pp. 1551-1556 ◽

Cited By ~ 1

Author(s):

John H. Brower ◽

Hilda C. Scott

Keyword(s):

Gamma Radiation ◽

Radiation Sensitivity ◽

Radiation Resistant ◽

Eggs And Larvae ◽

All Treatment

AbstractThe effects of seven gamma radiation dosages from 5 to 100 krad on all metamorphic stages of the spider beetle, Gibbium psylloides (Czenpinski), were studied. Five kilorads prevented development of adults from treated eggs and larvae. Some adults emerged from the pupal cocoon at all treatment levels except 50 and 100 krad, but their longevity was greatly reduced. Adults were fairly resistant to sterilizing effects of the radiation. Twenty kilokrads was not completely sterilizing to either males or females, but fecundity was greatly reduced. The longevity of treated adults was significantly reduced, but some survived for 20 weeks after a 20-krad exposure. Adults and pupae of this species were more radiation resistant than were most other stored-product Coleoptera.

Download Full-text

Prevalence and Antibiotic Resistance of Listeria Monocytogenes in Chicken Meat Retailers in Yazd, Iran

Journal of Environmental Health and Sustainable Development ◽

10.18502/jehsd.v4i4.2022 ◽

2019 ◽

Author(s):

Meysam Soleimani ◽

Elham Khalili Sadrabad ◽

Negar Hamidian ◽

Ali Heydari ◽

Fateme Akrami Mohajeri

Keyword(s):

Antibiotic Resistance ◽

Listeria Monocytogenes ◽

Culture Media ◽

The Elderly ◽

Chicken Meat ◽

Biochemical Tests ◽

Cross Sectional ◽

Principles And Standards ◽

Yazd City ◽

Retail Chicken Meat

Introduction: Listeria monocytogenes is a pathogen bacteria transmitted by food stuffs. Due to the lack of information about contamination of retail chicken meat to Listeria monocytogenes in Iran, this study aimed to determine the prevalence and antibiotic resistance of this bacterium in retail chicken meat in Yazd, Iran. Materials and Methods: This cross-sectional descriptive study was conducted from January 2018 to June 2018 on 811 randomly selected samples from four districts located in Yazd city, Iran. Isolation of Listeria monocytogenes was performed using enrichment and selective culture media as well as biochemical tests. The positive samples were confirmed by PCR assay. Results: In total, 247 samples (30.5%) were infected with one of the Listeria strains. Among the 247 samples, the isolates were 68 (27%) L. monocytogenes, 155 (63%) L. innocua, 5 (2%) L. seeligeri, 19 (8%) L. ivanovii. In the current study, the antibiotic resistance of positive samples was also evaluated that Listeria spp., especially Listeria monocytogenes were resistant to tetracycline and penicillin. Conclusions: The presence of this pathogenic microorganism in chicken meat can be a health risk, especially for pregnant women, the elderly, and those with immune deficiency. Considering the amount of contamination with L.monocytogenes in chicken and the high mortality rate caused by it, observance of the health principles and standards during the production, transportation, maintenance, and supply phases as well as training of employees in this industry are necessary.

Download Full-text

Radiation sensitivity of Acinetobacter spp. and their radicidation for preservation of meat at low temperature

Bangladesh Medical Research Council Bulletin ◽

10.3329/bmrcb.v35i2.2490 ◽

2009 ◽

Vol 35 (2) ◽

pp. 33-40 ◽

Cited By ~ 4

Author(s):

Sahadev Chandra Saha ◽

Balu Anand Chopade

Keyword(s):

Low Temperature ◽

Gamma Radiation ◽

Dose Level ◽

Radiation Sensitivity ◽

Acinetobacter Radioresistens ◽

Radiation Resistant ◽

Acinetobacter Spp ◽

Natural Contamination ◽

Gamma Radiations

Acinetobacter spp. isolated from meat to gamma radiations. Seven species of Acinetobacter viz. A. lwoffii M1; A. baumannii M8; A. calcoaceticus M19; A. junii M20; A. johnsonnii M23; A. haemolyticus M27 and A. radioresistens M25 isolated from meat were exposed to gamma radiation at the dose level of 0.1 to 10 KGy. The D10 value of Acinetobacter was found highest 1.25 KGy in A. radioresistens M25, which was 4 to 8 times higher than other genospecies of Acinetobacter. Acinetobacter radioresistens M25 contains one plasmid of 45 Kb. The radicidation dose of 4 KGy gamma radiations was found to be sufficient to eliminate the natural contamination of meat and contamination by Acinetobacter. To eliminate radiation resistant Acinetobacter contamination a dose of 4 to 5 KGy was required. Development of the radicidation process for preservation of meat to eliminate Acinetobacter as contaminants at low temperature is one of the new and interesting phenomena. Attempts of finding the appropriate radicidation dose for preservation of meat at low temperature will open up new avenues for commercial preservation of meat.DOI: http://dx.doi.org/10.3329/bmrcb.v35i2.2490Online: 11 August 2009Bangladesh Med Res Counc Bull 2009; 35: 33-40

Download Full-text

Relationship between the culturability of stressed Listeria monocytogenes cells in non-selective and selective culture media and the cellular esterase activity measured by solid phase cytometry

Journal of Microbiological Methods ◽

10.1016/j.mimet.2011.08.018 ◽

2011 ◽

Vol 87 (3) ◽

pp. 295-301 ◽

Cited By ~ 3

Author(s):

Claire Dupont ◽

Jean-Christophe Augustin

Keyword(s):

Listeria Monocytogenes ◽

Esterase Activity ◽

Solid Phase ◽

Culture Media

Download Full-text

Effect of Gamma Radiation on the Reduction of Salmonella strains, Listeria monocytogenes, and Shiga Toxin–Producing Escherichia coli and Sensory Evaluation of Minimally Processed Spinach (Tetragonia expansa)

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-108 ◽

2014 ◽

Vol 77 (10) ◽

pp. 1768-1772 ◽

Cited By ~ 10

Author(s):

ANA CAROLINA B. REZENDE ◽

MARIA CRYSTINA IGARASHI ◽

MARIA TERESA DESTRO ◽

BERNADETTE D. G. M. FRANCO ◽

MARIZA LANDGRAF

Keyword(s):

Escherichia Coli ◽

Listeria Monocytogenes ◽

Gamma Radiation ◽

Shiga Toxin ◽

Radiation Doses ◽

Minimally Processed ◽

Tetragonia Expansa ◽

Effects Of Irradiation On ◽

Spinach Leaves

This study evaluated the effects of irradiation on the reduction of Shiga toxin–producing Escherichia coli (STEC), Salmonella strains, and Listeria monocytogenes, as well as on the sensory characteristics of minimally processed spinach. Spinach samples were inoculated with a cocktail of three strains each of STEC, Salmonella strains, and L. monocytogenes, separately, and were exposed to gamma radiation doses of 0, 0.2, 0.4, 0.6, 0.8, and 1.0 kGy. Samples that were exposed to 0.0, 1.0, and 1.5 kGy and kept under refrigeration (4°C) for 12 days were submitted to sensory analysis. D10-values ranged from 0.19 to 0.20 kGy for Salmonella and from 0.20 to 0.21 for L. monocytogenes; for STEC, the value was 0.17 kGy. Spinach showed good acceptability, even after exposure to 1.5 kGy. Because gamma radiation reduced the selected pathogens without causing significant changes in the quality of spinach leaves, it may be a useful method to improve safety in the fresh produce industry.

Download Full-text

Neutron Radiation Effects on Lubricants and O-Rings for Target and Accelerator Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1024.127 ◽

2021 ◽

Vol 1024 ◽

pp. 127-133

Author(s):

Matteo Ferrari ◽

Aldo Zenoni ◽

Yong Joong Lee ◽

Alberto Andrighetto

Keyword(s):

Gamma Radiation ◽

Radiation Damage ◽

Radiation Effects ◽

Nuclear Reactor ◽

Neutron Radiation ◽

Radioactive Isotopes ◽

Structural Level ◽

Radiation Resistant ◽

Under Construction ◽

Neutron Radiation Effects

Lubricants and O-rings are necessarily used for the construction of many accelerator-driven facilities as spallation sources or facilities for the production of radioactive isotopes. During operation, such component will absorb high doses of mixed neutron and gamma radiation, that can degrade their mechanical and structural properties. Experimental radiation damage tests of these components are mandatory for the construction of the facility. Methodologies for irradiation in nuclear reactor mixed fields and post-irradiation examination of lubricating oils, greases and O-rings were developed and are here presented. Samples were characterized with standard mechanical and physical-chemical tests. Parametric studies on the dose rate effects have been performed on O-rings. A case studies for a specific O-ring application in a gate valve has been developed. Some of the tested samples showed a dramatic change of their properties with dose, while others remain stable. Results were collected on nine commercial greases, on one oil and on four commercial elastomeric O-rings. The most radiation resistant among the selected products are now considered for application in facilities under construction. The main mechanisms of neutron and gamma radiation damage on these polymers were investigated at the mechanical and structural level.

Download Full-text

Downregulation of MicroRNA-330 Correlates with the Radiation Sensitivity and Prognosis of Patients with Brain Metastasis from Lung Cancer

Cellular Physiology and Biochemistry ◽

10.1159/000479996 ◽

2017 ◽

Vol 42 (6) ◽

pp. 2220-2229 ◽

Cited By ~ 4

Author(s):

Li-Peng Jiang ◽

Zhi-Tu Zhu ◽

Yue Zhang ◽

Chun-Yan He

Keyword(s):

Lung Cancer ◽

Logistic Regression ◽

Radiation Therapy ◽

Survival Rate ◽

Brain Metastasis ◽

Cox Regression ◽

Radiation Sensitivity ◽

Extracranial Metastasis ◽

Radiation Resistant ◽

N Stage

Background: The present study sought to explore the role of microRNA-330 (miR-330) in predicting the radiation response and prognosis of patients with brain metastasis (BM) from lung cancer (LC). Methods: Patients with BM from LC were identified and classified into radiation-sensitive and radiation-resistant groups according to the overall survival rate, local and distant recurrence rate after conventional whole-brain radiation therapy. Quantitative realtime polymerase chain reaction (qRT-PCR) was used to detect miR-330 expression in serum. Receiver operating characteristic (ROC) curves were used to evaluate the prognostic value of miR-330 for the radiation sensitivity of brain metastasis from LC. Related clinical factors for radiation sensitivity were assessed by logistic regression analysis, and a survival analysis was conducted using COX regression and the Kaplan-Meier method. Results: MiR-330 exhibited lower expression in the radiation-sensitive group than in the radiation-resistant group. The area under the ROC curve of miR-330 for predicting radiation sensitivity was 0.898 (optimal cut-off value, 0.815), with a sensitivity of 71.7% and a specificity of 90.1%. After radiation therapy, patients with low miR-330 expression, compared to patients with high miR-330 expression, displayed a lower survival rate and a median survival time. MiR-330 expression was correlated with extracranial metastasis, maximum BM diameter, tumor-node-metastasis (TNM) stage and node (N) stage. Logistic regression and COX regression analyses revealed that extracranial metastasis, TNM stage, N stage and miR-330 expression were factors that influenced both radiation sensitivity and individual prognostic factors in patients with BM from LC. Conclusions: These findings indicate that the downregulation of miR-330 correlates with radiation sensitivity and poor prognosis in patients with BM from LC.

Download Full-text

Impact of Culture Media Composition, Nutrients Stress and Gamma Radiation on Biomass and Lipid of the Green Microalga, Dictyochloropsis splendida as a Potential Feedstock for Biodiesel Production

Baghdad Science Journal ◽

10.21123/bsj.2022.19.1.0043 ◽

2021 ◽

Vol 19 (1) ◽

Keyword(s):

Gamma Radiation ◽

Culture Media ◽

Biodiesel Production ◽

Media Composition ◽

Green Microalga

Download Full-text

Irradiation Temperature Influences Product Quality Factors of Frozen Vegetables and Radiation Sensitivity of Inoculated Listeria monocytogenes†

Journal of Food Protection ◽

10.4315/0362-028x-65.9.1406 ◽

2002 ◽

Vol 65 (9) ◽

pp. 1406-1410 ◽

Cited By ~ 18

Author(s):

BRENDAN A. NIEMIRA ◽

XUETONG FAN ◽

CHRISTOPHER H. SOMMERS

Keyword(s):

Listeria Monocytogenes ◽

Bacterial Population ◽

Response Pattern ◽

Radiation Sensitivity ◽

Irradiation Temperature ◽

Quality Factors ◽

Outbreak Strain ◽

Lima Beans ◽

Gamma Irradiated ◽

Different Response

Four frozen vegetables (broccoli, corn, lima beans, and peas) were gamma irradiated at subfreezing temperatures ranging from −5 to −20°C to determine (i) the radiation sensitivity of an inoculated outbreak strain of Listeria monocytogenes (ATCC 49594), (ii) the effect of changing irradiation conditions (i.e., temperature) on that sensitivity, and (iii) the effect of the recommended radiation dose on the texture and color of irradiated frozen vegetables. The amounts of radiation necessary to reduce the bacterial population by 90% (D10-values) for L. monocytogenes differed significantly among vegetables at each irradiation temperature. D10 increased significantly with decreasing temperature for all vegetables, with each vegetable showing a different response pattern. At an irradiation temperature of −5°C, D10 ranged from 0.505 kGy for broccoli to 0.613 kGy for corn. At −20°C, D10 ranged from 0.767 kGy for lima beans to 0.916 kGy for peas. At −20°C, radiation doses sufficient to achieve a 5-log10 kill (3.9 to 4.6 kGy) caused significant softening of peas and broccoli stems but not of corn or lima beans. Lower doses of comparable antimicrobial efficacy delivered at −5°C (2.5 to 3.1 kGy) did not cause significant changes in texture in any vegetable. Color varied significantly among the dose-temperature combinations only for broccoli florets; this variation did not demonstrate a clear pattern of quality changes in response to irradiation.

Download Full-text