Native bacterial communities and Listeria monocytogenes survival in soils collected from the Lower Mainland of British Columbia, Canada

2018 ◽  
Vol 64 (10) ◽  
pp. 695-705 ◽  
Author(s):  
Justin Falardeau ◽  
Khalil Walji ◽  
Maxime Haure ◽  
Karen Fong ◽  
Greg Taylor ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Bacterial Communities ◽  
Foodborne Pathogen ◽  
Amplicon Sequencing ◽  
Term Survival ◽  
Log Reduction ◽  
Neutral Ph ◽  
Significant Difference ◽  
Difference Test ◽  
Short Term Survival

Soil is an important reservoir for Listeria monocytogenes, a foodborne pathogen implicated in numerous produce-related outbreaks. Our objectives were to (i) compare the survival of L. monocytogenes among three soils, (ii) compare the native bacterial communities across these soils, and (iii) investigate relationships between L. monocytogenes survival, native bacterial communities, and soil properties. Listeria spp. populations were monitored on PALCAM agar in three soils inoculated with L. monocytogenes (∼5 × 106 CFU/g): conventionally farmed (CS), grassland transitioning to conventionally farmed (TS), and uncultivated grassland (GS). Bacterial diversity of the soils was analyzed using 16S rRNA targeted amplicon sequencing. A 2 log reduction of Listeria spp. was observed in all soils within 10 days, but at a significantly lower rate in GS (Fisher’s least significant difference test; p < 0.05). Survival correlated with increased moisture and a neutral pH. GS showed the highest microbial diversity. Acidobacteria was the dominant phylum differentiating CS and TS from GS, and was negatively correlated with pH, carbon, nitrogen, and moisture. High moisture content and neutral pH are likely to increase the ability of L. monocytogenes to persist in soil. This study confirmed that native bacterial communities and short-term survival of L. monocytogenes varies across soils.

scholarly journals Inactivation of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 on tomatoes using sodium dodecyl sulphate, levulinic acid and sodium hypochlorite solution

2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Oluwatosin Ademola Ijabadeniyi ◽  
Elizabeth Mnyandu
Keyword(s):  
Listeria Monocytogenes ◽  
Sodium Hypochlorite ◽  
Sodium Dodecyl Sulphate ◽  
Levulinic Acid ◽  
Sodium Dodecyl ◽  
Storage Period ◽  
Sodium Hypochlorite Solution ◽  
Hypochlorite Solution ◽  
Log Reduction ◽  
Significant Difference

The effectiveness of sodium dodecyl sulphate (SDS), sodium hypochlorite solution and levulinic acid in reducing the survival of heat adapted and chlorine adapted <em>Listeria monocytogenes</em> ATCC 7644 was evaluated. The results against heat adapted <em>L. monocytognes</em> revealed that sodium hypochlorite solution was the least effective, achieving log reduction of 2.75, 2.94 and 3.97 log CFU/mL for 1, 3 and 5 minutes, respectively. SDS was able to achieve 8 log reduction for both heat adapted and chlorine adapted bacteria. When used against chlorine adapted <em>L. monocytogenes</em> sodium hypochlorite solution achieved log reduction of 2.76, 2.93 and 3.65 log CFU/mL for 1, 3 and 5 minutes, respectively. Using levulinic acid on heat adapted bacteria achieved log reduction of 3.07, 2.78 and 4.97 log CFU/mL for 1, 3, 5 minutes, respectively. On chlorine adapted bacteria levulinic acid achieved log reduction of 2.77, 3.07 and 5.21 log CFU/mL for 1, 3 and 5 minutes, respectively. Using a mixture of 0.05% SDS and 0.5% levulinic acid on heat adapted bacteria achieved log reduction of 3.13, 3.32 and 4.79 log CFU/mL for 1, 3 and 5 minutes while on chlorine adapted bacteria it achieved 3.20, 3.33 and 5.66 log CFU/mL, respectively. Increasing contact time also increased log reduction for both test pathogens. A storage period of up to 72 hours resulted in progressive log reduction for both test pathogens. Results also revealed that there was a significant difference (P ≤ 0.05) between contact times, storage times and sanitizers. Findings from this study can be used to select suitable sanitizers and contact times for heat adapted and chlorine adapted <em>L. monocytogenes</em> in the fresh produce industry.

scholarly journals Persistent and sporadic Listeria monocytogenes strains do not differ when growing at 37 °C, in planktonic state, under different food associated stresses or energy sources

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Alexander J. Taylor ◽  
Matthew J. Stasiewicz
Keyword(s):  
Energy Source ◽  
Growth Rate ◽  
Listeria Monocytogenes ◽  
Foodborne Pathogen ◽  
Growth Curves ◽  
Stress Conditions ◽  
Energy Sources ◽  
Extrinsic Factors ◽  
Significant Difference ◽  
Original Goal

Abstract Background The foodborne pathogen Listeria monocytogenes causes the potentially lethal disease listeriosis. Within food-associated environments, L. monocytogenes can persist for long periods and increase the risk of contamination by continued presence in processing facilities or other food-associated environments. Most research on phenotyping of persistent L. monocytogenes’ has explored biofilm formation and sanitizer resistance, with less data examining persistent L. monocytogenes’ phenotypic responses to extrinsic factors, such as variations in osmotic pressure, pH, and energy source availability. It was hypothesized that isolates of persistent strains are able to grow, and grow faster, under a broader range of intrinsic and extrinsic factors compared to closely related isolates of sporadic strains. Results To test this hypothesis, 95 isolates (representing 74 isolates of 20 persistent strains and 21 isolates of sporadic strains) from a series of previous studies in retail delis, were grown at 37 °C, in (i) stress conditions: salt (0, 5, and 10% NaCl), pH (5.2, 7.2, and 9.2), and sanitizer (benzalkonium chloride, 0, 2, and 5 μg/mL) and (ii) energy sources: 25 mM glucose, cellobiose, glycogen, fructose, lactose, and sucrose; the original goal was to follow up with low temperature experiments for treatments where significant differences were observed. Growth rate and the ability to grow of 95 isolates were determined using high-throughput, OD600, growth curves. All stress conditions reduced growth rates in isolates compared to control (p < 0.05). In addition, growth varied by the tested energy sources. In chemically defined, minimal media there was a trend toward more isolates showing growth in all replicates using cellobiose (p = 0.052) compared to the control (glucose) and fewer isolates able to grow in glycogen (p = 0.02), lactose (p = 2.2 × 10− 16), and sucrose (p = 2.2 × 10− 16). Still, at least one isolate was able to consistently grow in every replicate for each energy source. Conclusions The central hypothesis was rejected, as there was not a significant difference in growth rate or ability to grow for retail deli isolates of persistent strains compared to sporadic strains for any treatments at 37 °C. Therefore, these data suggest that persistence is likely not determined by a phenotype unique to persistent strains grown at 37 °C and exposed to extrinsic stresses or variation in energy sources.

Short-term survival of ovarian cancer patients waiting more than six weeks after surgery before chemotherapy is given

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 5070-5070
Author(s):  
T. Paulsen ◽  
J. Kærn ◽  
K. Kjærheim ◽  
T. Haldorsen ◽  
C. Tropé
Keyword(s):  
Ovarian Cancer ◽  
Cancer Patients ◽  
Residual Disease ◽  
Short Term ◽  
Term Survival ◽  
Cox Regression Analysis ◽  
Significant Difference ◽  
Patient Groups ◽  
The Impact ◽  
Short Term Survival

5070 Background: To investigate the impact on short-term survival of time between surgery and start of first chemotherapy cycle in patients with advanced ovarian cancer. Methods: This prospective, population-based study comprised 371 patients with epithelial ovarian, tubal or peritoneal cancer diagnosed in 2002–2003. All patients underwent primary surgery, followed at different intervals by chemotherapy. The data were derived from notifications to the Norwegian Cancer Registry and included medical, surgical and histopathological records. Kaplan-Meier plots were used to show differences in survival, and Cox regression analysis was used to show the effect of prognostic factors on survival, expressed as hazard ratios (HRs). Results: No difference in survival between patient groups was seen when time between surgery and start of chemotherapy was divided into quartiles. The group of patients with interval between surgery and chemotherapy less than six weeks had inferior survival if they had residual disease after surgery. Adjusted HR = 2.36 (95% CI, 1.22–4.57). However, in the patient groups with interval more than six weeks, there was no significant difference in survival between patients without and with residual disease. Adjusted HR = 1.35 (0.51–3.56) versus HR = 1.64 (0.76–3.57). Conclusions: The interval between surgery and start of chemotherapy had no major impact on short-term survival after ovarian cancer. Patients might be included in chemotherapy trials when interval between surgery and start of chemotherapy is more than six weeks. [Table: see text] No significant financial relationships to disclose.

scholarly journals Effect of Chicken Manure-Based Fertiliser on Bacterial Communities and Diversity of Tomato Endosphere Microbiota

2021 ◽  
Vol 67 (3) ◽  
pp. 144-154
Author(s):  
Hafeez Ul Haq ◽  
Ye Li ◽  
Lingyue Jin ◽  
Ting Zhang ◽  
Linjie Cheng ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Amplicon Sequencing ◽  
Shannon Index ◽  
Chicken Manure ◽  
Rrna Gene ◽  
Beneficial Bacteria ◽  
Bacterial Phyla ◽  
Frequent Use ◽  
Significant Difference ◽  
Harmful Effects

Abstract The frequent use of chemical fertiliser produces harmful effects on the soil ecosystem. Therefore, biocompatible methods are used to improve plant health and production through natural fertiliser or plant beneficial microorganisms. This study aims to investigate the effect of amended chicken manure-based natural fertiliser on bacterial communities and plant beneficial bacteria of tomato endosphere microbiome using the high throughput 16S rRNA gene amplicon sequencing. The results showed Proteobacteria (89.4 ± 4.7% to 86.7 ± 3.9%), Actinobacteria (6.03 ± 2.9% to 3.56 ± 2.1%), and Firmicutes (3.34 ± 1.3% to 0.59 ± 0.3%) as the dominant bacterial phyla of tomato endophytic microbiome. Pseudomonas and Bacillus were the most abundant identifiable genera in the chicken manure root (CMR) (amended manure treatments) sample. There was no significant difference in alpha bacterial diversity (Shannon index: p = 0.48) and species richness (Chao 1: p = 0.43) between control original root (OR) and CMR. However, the distribution of the dominant phyla was mainly affected by manure fertilisation. The non-metric multidimensional scaling (NMDS) and PCoA of beta diversity analysis suggested a significant separation in bacterial communities of tomato endophytes between CMR and OR. The most differently abundant bacterial taxa belong to Bacteroidetes in the OR group, whereas the beneficial bacterial communities of Actinobacteria and Firmicutes were more abundant in the CMR group. Therefore, the chicken manure application can significantly affect bacterial communities of tomatoes´ root endophytic microbiome and effectively improve the abundance of the beneficial microbes as biofertilisers.

scholarly journals Efficacy of household washing pre-treatments and cooking methods for reduction of Listeria monocytogenes in artificially contaminated chicken offal

Food Research ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 166-174
Author(s):  
Chee Hao Kuan ◽  
Son Radu ◽  
Nor Ainy Mahyudin ◽  
John Yew Huat Tang ◽  
Siok Koon Yeo ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Water Flow ◽  
Foodborne Pathogens ◽  
Tap Water ◽  
Water Flow Rate ◽  
Foodborne Pathogen ◽  
Cooking Methods ◽  
Deep Frying ◽  
Log Reduction ◽  
Handling Practices

Consumption of chicken offal is common and famous among Malaysians as it is often served as one of the side dishes with rice. Chicken offal can be a potential source of Listeria monocytogenes because slaughtered animals are recognized as a reservoir for foodborne pathogens. L. monocytogenes is a dangerous foodborne pathogen which can cause severe foodborne listeriosis with high fatality rate. This study aimed to determine the efficacy of different washing pre-treatment and cooking methods to reduce L. monocytogenes in artificially contaminated chicken offal. All the washing pre-treatments (dip treatment in different water sources and wash treatment with different water flow rates) showed significant reduction of the pathogen (p<0.05) when the inoculated samples were treated from 2 mins onwards. Washing the inoculated samples under the water flow rate of 2 L/min was the most effective way to reduce the number of L. monocytogenes (approximately 1.97 log reduction after washing for 10 mins). For heat treatment study, deep-frying was the most effective cooking method followed by boiling and pan-frying to reduce L. monocytogenes where all L. monocytogenes cells (7.91 log10 CFU/g) were killed within 45 s under deep-frying treatment. Overall, the study indicated that washing under running tap water (2 L/min) and deep-frying was effective in reducing and controlling the microbial populations during food preparation. The findings from this study can serve as a safe preparation step and cooking guideline. It is necessary to implement safe steps in food handling practices among food handlers to minimize the risk of foodborne infection.

scholarly journals Survival of Listeria monocytogenes in turmeric-salt marinated short mackerel (Rastrelliger brachysoma) under isothermal storage temperature

Food Research ◽  
2020 ◽  
Vol 4 (S2) ◽  
pp. 48-56
Author(s):  
Ummul-Izzatul Y. ◽  
Nor-Khaizura M.A.R. ◽  
F.M. Ghazali ◽  
Son R. ◽  
Shafiqa-Atikah M.K. ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Protein Content ◽  
Storage Temperature ◽  
High Protein ◽  
Microbial Count ◽  
High Protein Content ◽  
Log Reduction ◽  
Significant Difference

Short mackerel (Rastrelliger brachysoma) is a common fish consumed in Malaysia. The high protein content of fish makes it prone to contamination with bacteria, including Listeria monocytogenes. Therefore, the objective of this study is to control the growth of L. monocytogenes by marinating short mackerel with turmeric-salt and storing at various temperatures. The short mackerel was treated with 70% of ethanol before marinating with turmeric-salt in a ratio (1:1). The short mackerel were inoculated with a concentration of 108 CFU/mL of L. monocytogenes and was stored at 0, 5, 10, 15, 20, and 25˚C for 21 days. The total microbial count and L. monocytogenes count were determined for every three days from 0 days to 21 days. The growth of L. monocytogenes in marinated mackerel was from 4.30 log CFU/g (0 days at 0 ˚C) to 5.22 log CFU/g (0 days at 25 ˚C). While the total of L. monocytogenes counts in non-marinated (control), short mackerel increased significantly based on temperature and time from 4.98 log CFU/g (0 days at 0 ˚C) to 6.22 log CFU/g (0 days at 25 ˚C). These results indicated that the growth of L. monocytogenes in the presence of turmeric-salt slowed compared with the non-marinated product, although the growth of L. monocytogenes was gradually increased throughout 21 days of storage. There was a significant difference (p<0.05) in the growth of L. monocytogenes with the storage temperature. In conclusion, the turmeric-salt marination has the potential to slow the growth of L. monocytogenes in short mackerel by approximately 0.07 log CFU/g - 2.81 log CFU/g of log reduction.

Long-term survival of the nasal NK/T cell lymphoma

2008 ◽  
Vol 149 (17) ◽  
pp. 801-805
Author(s):  
Péter Rajnics ◽  
László Krenács ◽  
András Kenéz ◽  
Zoltán Járay ◽  
Enikő Bagdi ◽  
...  
Keyword(s):  
T Cell ◽  
Treatment Guidelines ◽  
Cell Lymphoma ◽  
Treatment Options ◽  
Diagnostic Procedures ◽  
T Cell Lymphoma ◽  
Term Survival ◽  
Barr Virus ◽  
Significant Difference ◽  
Nk T Cell

The nasal NK/T cell lymphoma is a rare, extranodal non-Hodgkin lymphoma in western civilizations, which has poor prognosis. The Epstein–Barr virus can be detected in tumor cells in nearly all cases. There are no definite treatment guidelines in our days. There is no significant difference in survival between radiotherapy and chemotherapy according to Asian studies. In this case study we show our diagnostic procedures, our treatment options and we present the summary of this illness based on the data found in the literature.

Influence of age and shock severity on short-term survival in patients with cardiogenic shock

2021 ◽  
Author(s):  
Jacob C Jentzer ◽  
Benedikt Schrage ◽  
David R Holmes ◽  
Salim Dabboura ◽  
Nandan S Anavekar ◽  
...  
Keyword(s):  
Cardiogenic Shock ◽  
Mayo Clinic ◽  
Older Patients ◽  
Cox Proportional Hazards ◽  
Circulatory Support ◽  
Short Term ◽  
Term Survival ◽  
Risk Of Death ◽  
Coronary Syndrome ◽  
Short Term Survival

Abstract Aims Cardiogenic shock (CS) is associated with poor outcomes in older patients, but it remains unclear if this is due to higher shock severity. We sought to determine the associations between age and shock severity on mortality among patients with CS. Methods and results Patients with a diagnosis of CS from Mayo Clinic (2007–15) and University Clinic Hamburg (2009–17) were subdivided by age. Shock severity was graded using the Society for Cardiovascular Angiography and Intervention (SCAI) shock stages. Predictors of 30-day survival were determined using Cox proportional-hazards analysis. We included 1749 patients (934 from Mayo Clinic and 815 from University Clinic Hamburg), with a mean age of 67.6 ± 14.6 years, including 33.6% females. Acute coronary syndrome was the cause of CS in 54.0%. The distribution of SCAI shock stages was 24.1%; C, 28.0%; D, 33.2%; and E, 14.8%. Older patients had similar overall shock severity, more co-morbidities, worse kidney function, and decreased use of mechanical circulatory support compared to younger patients. Overall 30-day survival was 53.3% and progressively decreased as age or SCAI shock stage increased, with a clear gradient towards lower 30-day survival as a function of increasing age and SCAI shock stage. Progressively older age groups had incrementally lower adjusted 30-day survival than patients aged &lt;50 years. Conclusion Older patients with CS have lower short-term survival, despite similar shock severity, with a high risk of death in older patients with more severe shock. Further research is needed to determine the optimal treatment strategies for older CS patients.

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