Antibiotic susceptibility and genotyping by RAPD of Campylobacter jejuni isolated from retailed ready-to-eat sushi

A study to determine the antibiotic sensitivity pattern and genotyping using RAPD-PCR was performed on 50 C. jejuni isolated from sushi retailed in different supermarkets. With less than half of the isolates susceptible to the antibiotics tested, resistant to two or more antibiotics were observed in most of the isolates. The banding patterns obtained from RAPD-PCR revealed that no predominant clone exists and the bacterial population is rather diverse. Hence, the resistance of the C. jejuni to different classes of antibiotic as well as their diverse genotypes suggests that these C. jejuni isolates were generated from different sources in the contaminated supermarkets where sushi were retailed. Our data showed that C. jejuni can be an important reservoir for resistance genes and that study with comprehensive collections of samples are urgently required to establish better measures to reduce or eliminate the risk from antibiotic resistant and pathogenic bacteria originating from minimally processed ready-to-eat food

Performance characteristics and estimation of measurement uncertainty of two plating procedures for Listeria monocytogenes enumeration in chicken meat

The objectives highlighted in the present study were to determine the estimates of measurement uncertainty associated with PALCAM and CHROMagar TM Listeria media, to compare the efficacy between both media in relation to their measurement uncertainties. In addition, this study was carried out to assess the performance characteristics of spread and spiral plating procedures based on the comparison of Listeria monocytogenes enumeration between PALCAM and CHROMagar TM Listeria media. This work involved pure culture experiment, artificially contaminated samples experiment and naturally contaminated samples experiment. In pure culture experiment, PALCAM performance was relatively inferior to CHROMagar TM Listeria medium for both plating procedures. From the artificially contaminated samples, the results revealed that the values of repeatability, reproducibility, and measurement uncertainty at 95% confidence interval were comparable between both media under evaluation. However, at the level of naturally contaminated samples, the performance of CHROMagar TM Listeria medium was refutable as the presence of high number of competitive microorganisms reduced the clarity of the medium. The current emphasis in ensuring microbiological safety which requires use of accredited laboratories has led to measurable need for measurement uncertainty to ensure reliability of test results for global acceptance

Consumption of raw oysters: a risk factor for Vibrio parahaemolyticus infection

Vibrio parahaemolyticus is recognized as a frequent causal agent of human gastroenteritis due to the consumption of raw, undercooked or mishandled seafood in many Asian countries. The number of V. parahaemolyticus cases reported is on the rise, and this becomes a concern to the Asian countries as seafood is favoured by Asians. This study aimed to detect and quantify V. parahaemolyticus in raw oysters and to determine the risk associated with the consumption of raw oysters. A total of 30 oyster samples were collected and analysed in this study. MPN-PCR and MPN-Plating methods were employed and carried out concurrently to determine the prevalence of V. parahaemolyticus in raw oysters. The results showed that the prevalence of total V. parahaemolyticus in oysters was 50.00% (15/30) where the MPN/g range was 11000 MPN/g for MPN-PCR method, and 40.00% (12/30) where the MPN/g range was < 3 - 4300 MPN/g for MPN-Plating method. MPN-PCR method was able to estimate the level of virulence (tdh+ and trh+) V. parahaemolyticus in the raw oysters where 10.00% (3/30) of samples were identified to be in a range of 3 - 30 MPN/g. A microbial risk assessment was conducted based on the enumeration data obtained from MPN-PCR method using @risk. The probability of illness annually was 1.76 × 10-6 with a prediction of 31 cases to occur with respect to the exposed Malaysian population, while the rate per 100,000 people was estimated to be at 0.104. In addition, the antibiogram of V. parahaemolyticus was determined using Kirby Bauer Disk Diffusion Test and the results indicated that the isolates were highly resistant towards Bacitracin (100.00%), Vancomycin (100.00%) and were least resistant to Chloramphenicol (8.70%). The MAR index of the isolates ranged from 0.17 to 0.50. In accordance with the results from this study, the consumption of raw oysters is a risk factor for V. parahaemolyticus infection and proactive actions should be taken to reduce the risk of the pathogen in order to improve public health

Prevalence of Campylobacter spp. in retailed ready-to-eat sushi

The prevalence of Campylobacter spp. in retailed sushi were examined using the techniques of polymerase chain reaction (PCR) in combination with most probable number (MPN) to quantify the bacteria in 150 samples obtained from three supermarkets. The average prevalence of Campylobacter spp. in retailed sushi was 26.6% with 32%, 16% and 32% from supermarket I, II and III, respectively. Campylobacter jejuni was found to be the predominant species in retailed sushi with 82.49% of all Campylobacter spp. positive samples. Campylobacter coli was not detected in all samples. The maximum MPN number of Campylobacter spp. in retailed sushi purchased from supermarket I, II and III ranged from 3.6-11.0 MPN/g, 9.4->1100 MPN/g and 27-1100 MPN/g, respectively. The isolation of C. jejuni from a variety of ready-to-eat retail sushi may indicate that these products can act as possible vehicles for the dissemination of food-borne campylobacteriosis

Biofilm assessment of vibrio parahaemolyticus from seafood using random amplified polymorphism DNA-PCR

Pathogenic Vibrio parahaemolyticus is one of the leading causes of bacterial gastroenteritis in many countries. Among the strains examined, 36 RAPD-types were found when amplified with primers OPA8 and OPA10. The analysis shows the majority of V. parahaemolyticus isolates originated from seafood were branched into four major clusters at 18.2%, 20.7% 34% and 3.4% similarity levels. This suggests that there is potential for a single strain to be distributed widely within a population and there also potential for multiple contaminating strains of different clonal lineages to be present within the same population. Optimum temperature (37°C) was the highest and stable formation of biofilm. The total percentage of biofilm formation at 37°C was 33.33% for each of weak, moderate and strong biofilm producers. Room temperature produces 61.1% of weak biofilm producer, while 13. 89% for moderate biofilm producers and produce 25% of strong biofilm. While a total of 91.67% weak biofilm producers at 4°C and 8:33% for room temperature and no growth of strong biofilm. Upon analysis, strong biofilm was tracked from the largest group at 37°C and room temperature which produce 27.27% of strong biofilm producer respectively. Interestingly, they are derived from cockles

Monitoring and analysis of low-voltage network with smart grid architecture model by developing use cases

The objective of this paper is to show the characteristics of smart meters enabling to monitor and analyze the low-voltage (LV) network. This is achieved by developing use cases, where power quality and outage data are transferred from smart meters through distribution network to the control center. To visualize the monitoring process of LV network, the use cases are mapped into smart grid architecture model. The paper proposes a solution to analyze the LV network interruption and power quality problems (over-voltage, under-voltage, voltage sags, and swells). Thus, this paper provides a smart platform for monitoring LV network.© 2021 Authors. This work is licensed under the Creative Commons Attribution-Non-Commercial-NoDerivs 4.0 License https://creativecommons.org/licenses/by-nc-nd/4.0/.fi=vertaisarvioitu|en=peerReviewed

Rapid detection and enumeration of pathogenic Vibrio parahaemolyticus in raw vegetables from retail outlets

This study aims to determine the frequency and density of potentially pathogenic Vibrio parahaemolyticus, defned as those possessing thermostable-direct hemolysin (tdh) and/or tdh-related hemolysin (trh) genes, in raw salad vegetables at retail level in Selangor, Malaysia. A combination of Most Probable Number - Polymerase Chain Reaction (MPN-PCR) method was applied to detect the presence of tdh and/or trh gene-possessing V. parahaemolyticus and to enumerate their density in the samples. A total of 276 samples of vegetables commonly eaten raw in Malaysia (Cabbage = 30; Carrot = 31; Cucumber = 28; Four winged bean = 26; Indian pennywort = 17; Japanese parsley = 21; Lettuce = 16; Long bean = 32; Sweet potato = 29; Tomato = 38; Wild cosmos = 8) were analyzed. The samples were purchased from two supermarkets (A and B) and two wet markets (C and D). With the MPN-PCR technique, about 12.0% of the samples were positive for the presence of V. parahaemolyticus tdh-positive, with maximum densities of up to 39 MPN/g. The total frequency of V. parahaemolyticus trh-positive in the samples was 10.1%, with maximum concentration 15 MPN/g. V. parahaemolyticus tdh-positive was most prevalent in samples from Wet Market C (20.78%) and also in vegetable type Oenanthe stolonifera (Japanese parsley) with 19.0%, while V. parahaemolyticus trh-positive was predominant in samples from Wet Market D (16.7%) and was most frequent in both Oenanthe stolonifera (Japanese parsley) and Cucumis sativus (Cucumber) with 14.3% prevalence for each type. The results highlighted the fact that raw vegetables could be contaminated with virulent V. parahaemolyticus and could act as a transmission route, thus poses risk to consumers from the consumption of raw vegetables. To the author’s knowledge, this is the first assessment of V. parahaemolyticus carrying tdh and trh genes in raw vegetables from retail outlets in Malaysia

Static and dynamic postural stability in subjects with and without chronic low back pain

Background: The present study were undertaken to compare the static and dynamic postural stability among chronic low back pain and normal subjects. Most of the studies have been conducted on sports professionals. The present study focuses on recreationally active population, for which the activity levels are comparatively lesser.Methods: Thirty subjects (15 Chronic Low back Pain and 15 Normal subjects) were recruited randomly who’s demographic are not varied. The static and dynamic postural stability test namely postural sway meter and Star excursion balance test were analyzed. Data were analyzed using test of homogeneity and Independent sample t test.Results: Descriptive statistics reflected homogeneity of the study population. Independent sample t-test was used to compare values for static and dynamic stability between chronic low back pain and Normal subjects. It showed a statistically significant (P<0.05) difference in posterior and left lateral direction with t-value of -2.720 and -1.601 respectively for static stability. On the other hand, dynamic postural stability (SEBT) showed significant difference in all direction except on right leg; anteromedial, anterolateral and right and left posterior direction.Conclusions: Chronic low back pain group showed reduction in static and dynamic postural stability as compared to normals’.