WorldWideScience

Sample records for human food-borne pathogen

  1. Emerging Food-borne Pathogens

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The epidemiology of foodborne diseases is changing. While in manydeveloping nations the efficient treatment of diarrhoeal diseases through oral rehydration has probably led to the prevention of many food related deaths, the underlying problems have not been solved. In these countries, the disease incidence of food-and waterborne disease is still increasing, and now data from other parts of the world indicate that new foodborne pathogens have emerged as important public health problems. Over the last two decades, bacterial infections caused by Campylobacter and enterohaemorrhagic Escherichia coli have emerged, well-recognized pathogens, such as Salmonella enteritidis, have increased dramatically in disease incidence and important foodborne pathogens have become increasingly resistant to antimicrobial agents. The future strategy for prevention of foodborne disease should be founded in scientifically based evaluations of the whole food production chain ‘from farm to table’, including a description of the most important (risk) factors. Epidemiological studies of outbreaks as well as sporadic cases should be aimed at a better understanding of these factors. In terms of public health importance of the problem, the focus should be on the size of the problem, and the potential for improvement. The indications are that both in developed and developing countries there is significant potential for an improvement of the situation. With this aim in mind, international effort should focus on scientific assessments of the potential for risk reduction under different regional conditions.

  2. Methicillin-resistant Staphylococcus aureus: a food-borne pathogen?

    Science.gov (United States)

    Wendlandt, Sarah; Schwarz, Stefan; Silley, Peter

    2013-01-01

    Prior to the 1990s, most methicillin-resistant Staphylococcus aureus (MRSA) was hospital-associated (HA-MRSA); community-associated MRSA (CA-MRSA) then began to cause infections outside the health-care environment. The third significant emergence of MRSA has been in livestock animals [livestock-associated MRSA (LA-MRSA)]. The widespread and rapid growth in CA-MRSA and LA-MRSA has raised the question as to whether MRSA is indeed a food-borne pathogen. The observations on animal-to-animal and animal-to-human transfer of LA-MRSA have prompted research examining the origin of LA-MRSA and its capacity to cause zoonotic disease in humans. This review summarizes the current knowledge about MRSA from food-producing animals and foods with respect to the role of these organisms to act as food-borne pathogens and considers the available tools to track the spread of these organisms. It is clear that LA-MRSA and CA-MRSA and even HA-MRSA can be present in/on food intended for human consumption, but we conclude on the basis of the published literature that this does not equate to MRSA being considered a food-borne pathogen.

  3. Human sparganosis, a neglected food borne zoonosis.

    Science.gov (United States)

    Liu, Quan; Li, Ming-Wei; Wang, Ze-Dong; Zhao, Guang-Hui; Zhu, Xing-Quan

    2015-10-01

    Human sparganosis is a food borne zoonosis caused by the plerocercoid larvae (spargana) of various diphyllobothroid tapeworms of the genus Spirometra. Human infections are acquired by ingesting the raw or undercooked meat of snakes or frogs, drinking untreated water, or using raw flesh in traditional poultices. More than 1600 cases of sparganosis have been documented worldwide, mostly in east and southeast Asia. Sporadic cases have been reported in South America, Europe, and Africa, and several cases have been described in travellers returning from endemic regions. Epidemiological data suggest that the increased effect of sparganosis on human health is because of greater consumption of raw meat of freshwater frogs and snakes. This Review provides information about the Spirometra parasites and their lifecycles, summarises clinical features, diagnosis, and treatment of human sparganosis, and describes geographical distribution and infection characteristics of Spirometra parasites in host animals.

  4. DNA microarray technique for detecting food-borne pathogens

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    Xing GAO

    2012-08-01

    Full Text Available Objective To study the application of DNA microarray technique for screening and identifying multiple food-borne pathogens. Methods The oligonucleotide probes were designed by Clustal X and Oligo 6.0 at the conserved regions of specific genes of multiple food-borne pathogens, and then were validated by bioinformatic analyses. The 5' end of each probe was modified by amino-group and 10 Poly-T, and the optimized probes were synthesized and spotted on aldehyde-coated slides. The bacteria DNA template incubated with Klenow enzyme was amplified by arbitrarily primed PCR, and PCR products incorporated into Aminoallyl-dUTP were coupled with fluorescent dye. After hybridization of the purified PCR products with DNA microarray, the hybridization image and fluorescence intensity analysis was acquired by ScanArray and GenePix Pro 5.1 software. A series of detection conditions such as arbitrarily primed PCR and microarray hybridization were optimized. The specificity of this approach was evaluated by 16 different bacteria DNA, and the sensitivity and reproducibility were verified by 4 food-borne pathogens DNA. The samples of multiple bacteria DNA and simulated water samples of Shigella dysenteriae were detected. Results Nine different food-borne bacteria were successfully discriminated under the same condition. The sensitivity of genomic DNA was 102 -103pg/ μl, and the coefficient of variation (CV of the reproducibility of assay was less than 15%. The corresponding specific hybridization maps of the multiple bacteria DNA samples were obtained, and the detection limit of simulated water sample of Shigella dysenteriae was 3.54×105cfu/ml. Conclusions The DNA microarray detection system based on arbitrarily primed PCR can be employed for effective detection of multiple food-borne pathogens, and this assay may offer a new method for high-throughput platform for detecting bacteria.

  5. Antimicrobial Impacts of Essential Oils on Food Borne-Pathogens.

    Science.gov (United States)

    Ozogul, Yesim; Kuley, Esmeray; Ucar, Yilmaz; Ozogul, Fatih

    2015-01-01

    The antimicrobial activity of twelve essential oil (pine oil, eucalyptus, thyme, sage tea, lavender, orange, laurel, lemon, myrtle, lemon, rosemary and juniper) was tested by a disc diffusion method against food borne pathogens (Escherichia coli, Salmonella paratyphi A, Klebsiella pneumoniae, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Campylobacter jejuni, Enterococcus faecalis, Staphylococcus aureus). The major components in essential oils were monoterpenes hydrocarbons, α-pinene, limonene; monoterpene phenol, carvacrol and oxygenated monoterpenes, camphor, 1,8-cineole, eucalyptol, linalool and linalyl acetate. Although the antimicrobial effect of essential oils varied depending on the chemical composition of the essential oils and specific microorganism tested, majority of the oils exhibited antibacterial activity against one or more strains. The essential oil with the lowest inhibition zones was juniper with the values varied from 1.5 to 6 mm. However, the components of essential oil of thyme and pine oil are highly active against food borne pathogen, generating the largest inhibition zones for both gram negative and positive bacteria (5.25-28.25 mm vs. 12.5-30 mm inhibition zones). These results indicate the possible use of the essential oils on food system as antimicrobial agents against food-borne pathogen. The article also offers some promising patents on applications of essential oils on food industry as antimicrobial agent.

  6. Enteroaggregative Escherichia coli: An Emerging Enteric Food Borne Pathogen

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    P. Kaur

    2010-01-01

    Full Text Available Enteroaggregative Escherichia coli (EAEC are quite heterogeneous category of an emerging enteric pathogen associated with cases of acute or persistent diarrhea worldwide in children and adults, and over the past decade has received increasing attention as a cause of watery diarrhea, which is often persistent. EAEC infection is an important cause of diarrhea in outbreak and non-outbreak settings in developing and developed countries. Recently, EAEC has been implicated in the development of irritable bowel syndrome, but this remains to be confirmed. EAEC is defined as a diarrheal pathogen based on its characteristic aggregative adherence (AA to HEp-2 cells in culture and its biofilm formation on the intestinal mucosa with a “stacked-brick” adherence phenotype, which is related to the presence of a 60 MDa plasmid (pAA. At the molecular level, strains demonstrating the aggregative phenotype are quite heterogeneous; several virulence factors are detected by polymerase chain reaction; however, none exhibited 100% specificity. Although several studies have identified specific virulence factor(s unique to EAEC, the mechanism by which EAEC exerts its pathogenesis is, thus, far unknown. The present review updates the current knowledge on the epidemiology, chronic complications, detection, virulence factors, and treatment of EAEC, an emerging enteric food borne pathogen.

  7. Biofilm-associated persistence of food-borne pathogens.

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    Bridier, A; Sanchez-Vizuete, P; Guilbaud, M; Piard, J-C; Naïtali, M; Briandet, R

    2015-02-01

    Microbial life abounds on surfaces in both natural and industrial environments, one of which is the food industry. A solid substrate, water and some nutrients are sufficient to allow the construction of a microbial fortress, a so-called biofilm. Survival strategies developed by these surface-associated ecosystems are beginning to be deciphered in the context of rudimentary laboratory biofilms. Gelatinous organic matrices consisting of complex mixtures of self-produced biopolymers ensure the cohesion of these biological structures and contribute to their resistance and persistence. Moreover, far from being just simple three-dimensional assemblies of identical cells, biofilms are composed of heterogeneous sub-populations with distinctive behaviours that contribute to their global ecological success. In the clinical field, biofilm-associated infections (BAI) are known to trigger chronic infections that require dedicated therapies. A similar belief emerging in the food industry, where biofilm tolerance to environmental stresses, including cleaning and disinfection/sanitation, can result in the persistence of bacterial pathogens and the recurrent cross-contamination of food products. The present review focuses on the principal mechanisms involved in the formation of biofilms of food-borne pathogens, where biofilm behaviour is driven by its three-dimensional heterogeneity and by species interactions within these biostructures, and we look at some emergent control strategies.

  8. [Development of single base extension-tags microarray for the detection of food-borne pathogens].

    Science.gov (United States)

    Lu, Changyong; Shi, Chunlei; Zhang, Chunxiu; Chen, Jing; Shi, Xianming

    2009-04-01

    We developed single base extension-tags (SBE-tags) microarray to detect eight common food-borne pathogens, including Staphylococcus aureus, Vibrio parahaemolyticus, Listeria monocytogenes, Salmonella, Enterobacter sakazaki, Shigella, Escherichia coli O157:H7 and Campylobacter jejuni. With specific PCR primers identified and integrated for eight food-borne pathogens, target sequences were amplified and purified as template DNA of single base extension-tags reaction. The products were hybridized to microarrays and scanned for fluorescence intensity. The experiment showed a specific and simultaneous detection of eight food-borne pathogens. The system limits is 0.1 pg for a genomic DNA and 5x10(2) CFU/mL for Salmonella typhimurium cultures. The single base extension-tags assay can be used to detect food-borne pathogens rapidly and accurately with a high sensitivity, and provide an efficient way for diagnosis and control of disease caused by food-borne pathogens.

  9. Ecophysiology of food-borne pathogens: Essential knowledge to improve food safety.

    Science.gov (United States)

    McMeekin, T A; Hill, C; Wagner, M; Dahl, A; Ross, T

    2010-05-30

    The term ecophysiology suggests that a natural connection exists between microbial ecology and microbial physiology, the former being concerned with the responses of microbial populations to environmental influences, and the latter with activities within individual cells. In this contribution we choose to integrate these as far as possible and also indicate how understanding of both is benefiting from advances in molecular biology and informatics. We consider how microbial dispersal relates to microbial survival, recovery and proliferation, including the significance of random factors (stochasticity) in continuation of bacterial lineages, observing that minor environmental changes, can greatly influence the potential for food-borne disease. Homeostasis and membrane transport are identified as potential targets to control food-borne pathogens and the role of compatible solutes in stress protection is presented. Phenotypic variation in genetically homogeneous populations is highlighted as a major component of the overall microbial survival strategy. The marked influence and potential of predictive microbiology as an aid to food safety management is discussed, as is the need for greater knowledge of the ecophysiology of microbes in the growth/no growth region. The application of fundamental scientific principles, including thermodynamics, chemistry and microbial physiology is advocated as the basis for development of theory underpinning microbial ecophysiology. Advancing microbial food safety continues to require development of rapid, quantitative methods as an early warning system and mechanism to curtail microbial food-borne disease outbreaks. However, advances made by technologists and molecular biologists must be combined with knowledge of ecophysiology: e.g. biological rates will continue to constrain resolution of the recalcitrant problem of reducing the time required for enrichment processes. The discussion presented leads to the conclusion that microbial and

  10. Transfer of genetic material between pathogenic and food-borne yeasts

    DEFF Research Database (Denmark)

    Mentel, M.; Spirek, M.; Jorck-Ramberg, D.

    2006-01-01

    Many pathogenic yeast species are asexual and therefore not involved in intra- or interspecies mating. However, high-frequency transfer of plasmid DNA was observed when pathogenic and food-borne yeasts were grown together. This property could play a crucial role in the spread of virulence and drug...

  11. Transfer of genetic material between pathogenic and food-borne yeasts

    DEFF Research Database (Denmark)

    Mentel, M.; Spirek, M.; Jorck-Ramberg, D.

    2006-01-01

    Many pathogenic yeast species are asexual and therefore not involved in intra- or interspecies mating. However, high-frequency transfer of plasmid DNA was observed when pathogenic and food-borne yeasts were grown together. This property could play a crucial role in the spread of virulence and drug...... resistance factors among yeasts....

  12. Pathogenic potential and genotypic diversity of Campylobacter jejuni: a neglected food-borne pathogen in Brazil.

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    Frazão, Miliane Rodrigues; Medeiros, Marta Inês Cazentini; Duque, Sheila da Silva; Falcão, Juliana Pfrimer

    2017-03-01

    Purpose and methodology.Campylobacter jejuni is a major zoonotic pathogen that causes food-borne gastroenteritis worldwide. However, there are only a few studies available that have molecularly characterized C. jejuni strains isolated in Brazil. The aim of this study was to genotype 111 C. jejuni strains isolated from sick humans (43), monkey faeces (19), chicken faeces (14), chicken meat (33) and sewage (2) between 1996 and 2016 in Brazil using flaA-SVR (short variable region) sequencing and PFGE. Furthermore, the presence of 16 virulence genes was analysed by PCR. Using PFGE and flaA-SVR sequencing, the 111 C. jejuni strains studied were grouped into three and two clusters, respectively, and some strains of different origin presented a similarity of ≥80 %. In total, 35 flaA-SVR alleles were detected. Alleles gt45, gt49 and gt57 were the most prevalent, in contrast with those frequently described in the PubMLST database. All 111 C. jejuni strains contained the genes flaA, flhA, cadF, docA, cdtA, cdtB, cdtC, iamA, ciaB, sodB, dnaJ, pldA, racR and csrA. The wlaN gene was detected in 11 strains (9.9 %), and the virB11 in just one strain (0.9 %). In conclusion, the pathogenic potential of the C. jejuni strains studied was highlighted by the high frequency of the majority of the virulence genes searched. The flaA-SVR sequencing and PFGE results showed that some of the strains studied presented a high genotypic similarity, suggesting potential for transmission between animal sources and humans in this country. Altogether, the results characterize further C. jejuni isolates from Brazil, an important producer and exporter of chicken meat.

  13. Biocontrol and Rapid Detection of Food-Borne Pathogens Using Bacteriophages and Endolysins.

    Science.gov (United States)

    Bai, Jaewoo; Kim, You-Tae; Ryu, Sangryeol; Lee, Ju-Hoon

    2016-01-01

    Bacteriophages have been suggested as natural food preservatives as well as rapid detection materials for food-borne pathogens in various foods. Since Listeria monocytogenes-targeting phage cocktail (ListShield) was approved for applications in foods, numerous phages have been screened and experimentally characterized for phage applications in foods. A single phage and phage cocktail treatments to various foods contaminated with food-borne pathogens including E. coli O157:H7, Salmonella enterica, Campylobacter jejuni, Listeria monocytogenes, Staphylococcus aureus, Cronobacter sakazakii, and Vibrio spp. revealed that they have great potential to control various food-borne pathogens and may be alternative for conventional food preservatives. In addition, phage-derived endolysins with high host specificity and host lysis activities may be preferred to food applications rather than phages. For rapid detection of food-borne pathogens, cell-wall binding domains (CBDs) from endolysins have been suggested due to their high host-specific binding. Fluorescence-tagged CBDs have been successfully evaluated and suggested to be alternative materials of expensive antibodies for various detection applications. Most recently, reporter phage systems have been developed and tested to confirm their usability and accuracy for specific detection. These systems revealed some advantages like rapid detection of only viable pathogenic cells without interference by food components in a very short reaction time, suggesting that these systems may be suitable for monitoring of pathogens in foods. Consequently, phage is the next-generation biocontrol agent as well as rapid detection tool to confirm and even identify the food-borne pathogens present in various foods.

  14. Biocontrol and Rapid Detection of Food-borne Pathogens Using Bacteriophages and Endolysins

    Directory of Open Access Journals (Sweden)

    Jaewoo eBai

    2016-04-01

    Full Text Available Bacteriophages have been suggested as natural food preservatives as well as rapid detection materials for food-borne pathogens in various foods. Since Listeria monocytogenes-targeting phage cocktail (ListShield was approved for applications in foods, numerous phages have been screened and experimentally characterized for phage applications in foods. A single phage and phage cocktail treatments to various foods contaminated with food-borne pathogens including E. coli O157:H7, Salmonella enterica, Campylobacter jejuni, Listeria monocytogenes, Staphylococcus aureus, Cronobacter sakazakii, and Vibrio spp. revealed that they have great potential to control various food-borne pathogens and may be alternative for conventional food preservatives. In addition, phage-derived endolysins with high host specificity and host lysis activities may be preferred to food applications rather than phages. For rapid detection of food-borne pathogens, cell-wall binding domains (CBDs from endolysins have been suggested due to their high host-specific binding. Fluorescence-tagged CBDs have been successfully evaluated and suggested to be alternative materials of expensive antibodies for various detection applications. Most recently, reporter phage systems have been developed and tested to confirm their usability and accuracy for specific detection. These systems revealed some advantages like rapid detection of only viable pathogenic cells without interference by food components in a very short reaction time, suggesting that these systems may be suitable for monitoring of pathogens in foods. Consequently, phage is the next-generation biocontrol agent as well as rapid detection tool to confirm and even identify the food-borne pathogens present in various foods.

  15. Rapid detection, characterization, and enrumeration of food-borne pathogens

    Science.gov (United States)

    In recent years, there has been much research activity on the development of methodologies that are rapid, accurate, and ultrasensitive for detecting pathogenic microorganisms in food. Rapid methods include immunological systems such as the lateral flow assays and enzyme-linked immunosorbent assays...

  16. Knowledge of Brucella as a food-borne pathogen

    Science.gov (United States)

    Although Brucella spp. are known for causing reproductive losses in domestic livestock, they are also capable of infecting humans and causing clinical disease. Human infection with Brucella is almost exclusively a result of direct contact with infected animals or consumption of products made from un...

  17. Investigation of Anti-bacterial Activity against Food-borne Pathogens among Korean Domestic Algae

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    Ki-hyo Jang

    2015-03-01

    Full Text Available The aim of this study is to explore algal species with anti-bacterial activity against six food-borne pathogens. Among 51 marine algae, Laurencia okamurae Yamada and Dictyopteris undulata Holmes was elucidated to have a potent anti-bacterial activity against food-borne pathogens. Laurencia okamurae Yamada showed the clear zone around agar well on B. cereus, S. aureusand L. monocytogenes-spreading agar plate. Dictyopteris undulata Holmes had the anti-bacterial activity against S. chorelaesuis, B. cereus, S. aureus and L. monocytogenes on bacterial spreading agar plates. Antibacterial activity of L. okamurae Yamada and D. undulata Holmes had specifically susceptibility for B. cereus, S. aureus and L. monocytogenes and were superior to streptomycin, the authentic antibiotics. It is anticipated that new food preservatives can be explored and developed on the basis of this study.

  18. Sugar fatty acid esters inhibit biofilm formation by food-borne pathogenic bacteria

    OpenAIRE

    Furukawa, Soichi; Akiyoshi, Yuko; O’Toole, George A; Ogihara, Hirokazu; Morinaga, Yasushi

    2010-01-01

    Effects of food additives on biofilm formation by food-borne pathogenic bacteria were investigated. Thirty-three potential food additives and 3 related compounds were added to the culture medium at concentrations from 0.001 to 0.1% (w/w), followed by inoculation and cultivation of five biofilm-forming bacterial strains for the evaluation of biofilm formation. Among the tested food additives, 21 showed inhibitory effects of biofilm formation by Staphylococcus aureus and Escherichia coli, and i...

  19. [Studies on rapid detection of food-borne pathogenic bacteria by nucleic acid testing and related technology].

    Science.gov (United States)

    Cao, Wei; Wang, Mingzhong; Wang, Xiaoying; Liu, Xiumei

    2008-03-01

    The traditional methods of bacteria isolation, cultivation and identification are time-consuming, which can't meet the needs of the control and prevention of food-borne diseases. Recently, various kinds of rapid methods for food-borne pathogenic bacteria detection have emerged with the prompt development of nucleic acid testing technology. The application studies on polymerase chain reaction and the techniques derived from it, nucleic acid isothermal amplification, oligonucleotide microarray, immunomagnetic separation and DNA biosensing on food-borne pathogenic bacteria including Salmonella, Staphylococcus aureus and Enterohemorrhagic Escherchia coli, etc. were reviewed.

  20. Food-borne pathogens of animal origin-diagnosis, prevention, control and their zoonotic significance: a review.

    Science.gov (United States)

    Dhama, K; Rajagunalan, S; Chakraborty, S; Verma, A K; Kumar, A; Tiwari, R; Kapoor, S

    2013-10-15

    The term food borne diseases or food-borne illnesses or more commonly food poisoning are used to denote gastrointestinal complications that occur following recent consumption of a particular food or drink. Millions of people suffer worldwide every year and the situation is quiet grave in developing nations creating social and economic strain. The food borne pathogens include various bacteria viz., Salmonella, Campylobacter, Escherichia coli, Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus, Arcobacter, Clostridium perfringens, Cl. botulinum and Bacillus cereus and helminths viz., Taenia. They also include protozoa viz., Trichinella, Sarcocystis, Toxoplasma gondii and Cryptosporidium parvum. The zoonotic potential and the ability to elaborate toxins by many of the microbes causing fatal intoxication are sufficient to understand the seriousness of the situation. The viral agents being host specific their transmission to humans through food of animal origin is not yet confirmed although these animal viruses are similar to that of viruses infecting human. Food-borne bacteria; protozoa and helminthes have complex distribution pattern in the environment and inside the host system. This along with complexity of the maintenance chain and life cycle (of parasites) has made it difficult for epidemiologist and diagnostician to undertake any immediate safety measures against them. Serological and molecular diagnostic tests viz. ELISA, Latex agglutination test, Lateral flow assays, Immunomagnetic separation assays, molecular assays viz. Polymerase Chain Reaction (PCR), multiplex PCR, immuno-PCR, Realtime PCR, Random Amplified Polymorphic DNA (RAPD)-PCR, DNA microarrays and probes are widely used. Along with these LAMP assays, Capillary Electrophoresis-Single Strand Confirmation polymorphism (CE-SSCP); Flow cytometry, FISH, Biosensors, Direct epifluorescent filter technique, nanotechnology based methods and sophisticated tools (ultrasonography, magnetic resonance

  1. Co-infection dynamics of a major food-borne zoonotic pathogen in chicken

    DEFF Research Database (Denmark)

    Skanseng, Beate; Trosvik, Pal; Zimonja, Monika;

    2007-01-01

    with Broilact, which is a product consisting of bacteria from the intestinal flora of healthy hens) and spontaneous. The two treatments resulted in completely different background floras, yet similar Campylobacter colonisation patterns were detected in both groups. This suggests that it is the chicken host......A major bottleneck in understanding zoonotic pathogens has been the analysis of pathogen co-infection dynamics. We have addressed this challenge using a novel direct sequencing approach for pathogen quantification in mixed infections. The major zoonotic food-borne pathogen Campylobacter jejuni....... We analysed time-series data, following the Campylobacter colonisation, as well as the dominant background flora of chickens. Data were collected from the infection at day 16 until the last sampling point at day 36. Chickens with two different background floras were studied, mature ( treated...

  2. Comparison of Three Different DNA Extraction Methods for Linguatula serrata as a Food Born Pathogen.

    Science.gov (United States)

    Eslami, Gilda; Khalatbari-Limaki, Sepideh; Ehrampoush, Mohammad Hasan; Gholamrezaei, Mostafa; Hajimohammadi, Bahador; Oryan, Ahmad

    2017-01-01

    One of the most important items in molecular characterization of food-borne pathogens is high quality genomic DNA. In this study, we investigated three protocols and compared their simplicity, duration and costs for extracting genomic DNA from Linguatula serrata. The larvae were collected from the sheep's visceral organs from the Yazd Slaughterhouse during May 2013. DNA extraction was done in three different methods, including commercial DNA extraction kit, Phenol Chloroform Isoamylalcohol (PCI), and salting out. Extracted DNA in each method was assessed for quantity and quality using spectrophotometery and agarose gel electrophoresis, respectively. The less duration was regarding to commercial DNA extraction kit and then salting out protocol. The cost benefit one was salting out and then PCI method. The best quantity was regarding to PCI with 72.20±29.20 ng/μl, and purity of OD260/OD280 in 1.76±0.947. Agarose gel electrophoresis for assessing the quality found all the same. Salting out is introduced as the best method for DNA extraction from L. seratta as a food-borne pathogen with the least costand appropriate purity. Although, the best purity was regarding to PCI but PCI is not safe as salting out. In addition, the duration of salting out was less than PCI. The least duration was seen in commercial DNA extraction kit, but it is expensive and therefore is not recommended for developing countries where consumption of offal is common.

  3. Acanthamoeba polyphaga, a potential environmental vector for the transmission of food-borne and opportunistic pathogens.

    Science.gov (United States)

    Anacarso, Immacolata; de Niederhäusern, Simona; Messi, Patrizia; Guerrieri, Elisa; Iseppi, Ramona; Sabia, Carla; Bondi, Moreno

    2012-06-01

    The endosymbiotic relationship could represent for many bacteria an important condition favouring their spread in the environment and in foods. For this purpose we studied the behaviour of some food-borne and opportunistic pathogens (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Salmonella enterica serovar Enteritidis, Aeromonas hydrophila, Yersinia enterocolitica) when internalized in Acanthamoeba polyphaga. Our results confirm the capability of the bacteria tested to grow within amoebal hosts. We can observe two types of interactions of the bacteria internalized in A. polyphaga. The first type, showed by Y. enterocolitica and A. hydrophila, was characterized by an early replication, probably followed by the killing and digestion of the bacteria. The second type, showed by E. faecalis and S. aureus was characterized by the persistence and grow inside the host without lysis. Lastly, when amoebae were co-cultured with L. monocytogenes and S. Enteritidis, an eclipse phase followed by an active intracellular growth was observed, suggesting a third type of predator-prey trend. The extracellular count in presence of A. polyphaga, as a result of an intracellular multiplication and subsequent release, was characterized by an increase of E. faecalis, S. aureus, L. monocytogenes and S. Enteritidis, and by a low or absent cell count for Y. enterocolitica and A. hydrophila. Our study suggests that the investigated food-borne and opportunistic pathogens are, in most cases, able to interact with A. polyphaga, to intracellularly replicate and, lastly, to be potentially spread in the environment, underlining the possible role of this protozoan in food contamination.

  4. A quantum-dot-based fluoroassay for detection of food-borne pathogens.

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    Mohamadi, Elaheh; Moghaddasi, Mohammadali; Farahbakhsh, Afshin; Kazemi, Abbass

    2017-09-01

    Evaluation of the distribution capability of food-borne pathogens existing in food products by taking the advantage of quantum dots (QDs) for their photoluminescence properties was carried out. Bacteria namely Escherichia coli (E. coli) labelled with CdSe-QDs were examined both on an Agar nutrient and ground fish substrates in order to observe their growth rate in different environments in the Lab. A sample with an appropriate concentration ratio 10(7)CFU/mL of bacteria/CdSe-QDs was empirically selected from the samples which were grown on the Agar containing plates. The selected sample was also tested on a ground fish substrate as a real food sample. The bacterial growth was observed under the irradiation of UV light and the growth patterns were investigated for 3 successive days. The growth patterns indicated that E. coli can stay alive and can be distributed on food products so that the growth can be easily monitored. This approach makes bacterial growth on food products detectable so that it can be used as a bacteria-QD assay for an easy detection of food borne pathogens grown on a food sample. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. An alternative chemical redox method for the production of bispecific antibodies: implication in rapid detection of food borne pathogens.

    Directory of Open Access Journals (Sweden)

    Mohammad Owais

    Full Text Available Bi-functional antibodies with the ability to bind two unrelated epitopes have remarkable potential in diagnostic and bio-sensing applications. In the present study, bispecific antibodies that recognize human red blood cell (RBC and the food borne pathogen Listeria monocytogenes (L. monocytogenes were engineered. The procedure involves initial reduction of a mixture of anti-RBC and anti-Listeria antibodies followed by gradual re-oxidation of the reduced disulphides. This facilitates association of the separated antibody chains and formation of hybrid immunoglobulins with affinity for the L. monocytogenes and human RBC. The bispecific antibodies caused the agglutination of the RBCs only in the presence of L. monocytogenes cells. The agglutination process necessitated the specific presence of L. monocytogenes and the red colored clumps formed were readily visible with naked eyes. The RBC agglutination assay described here provides a remarkably simple approach for the rapid and highly specific screening of various pathogens in their biological niches.

  6. ANTIBACTERIAL ACTIVITY OF SIMAROUBA GLAUCA LEAF EXTRACTS AGAINST FOOD BORNE SPOILAGE AND PATHOGENIC MICROORGANISMS

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    B. L. Jangale et al.

    2012-02-01

    Full Text Available Crude ethanol and methanol extracts from dried and fresh leaves of Simarouba glauca were tested for their inhibitory activity against two food borne pathogenic microorganisms (Staphylococcus aeureus and Escherichia coli and two food spoilage microorganism (Bacillus subtilis and Pseudomonas aeurogenosa. Screening for antimicrobial activity using well diffusion assay showed the inhibition against entire tested microorganisms. On the other hand the maximum zone of inhibition was recorded of fresh leaves methanol extract (FLM about 11 mm against Escherichia coli and the lowest zone of inhibition was recorded of fresh leaves methanol extract (FLM about 2 mm against Bacillus subtilis. Minimum inhibitory concentrations (MIC’s of extracts were determined using agar dilution method on the same test microorganisms. Fresh leaves methanol (FLM extract gave MIC value ranging from 160 to 10,240 parts per million (ppm. Result showed that the Bacillus subtilis was the most sensitive microorganism.

  7. Recent advances in bacteriophage based biosensors for food-borne pathogen detection.

    Science.gov (United States)

    Singh, Amit; Poshtiban, Somayyeh; Evoy, Stephane

    2013-01-30

    Foodborne diseases are a major health concern that can have severe impact on society and can add tremendous financial burden to our health care systems. Rapid early detection of food contamination is therefore relevant for the containment of food-borne pathogens. Conventional pathogen detection methods, such as microbiological and biochemical identification are time-consuming and laborious, while immunological or nucleic acid-based techniques require extensive sample preparation and are not amenable to miniaturization for on-site detection. Biosensors have shown tremendous promise to overcome these limitations and are being aggressively studied to provide rapid, reliable and sensitive detection platforms for such applications. Novel biological recognition elements are studied to improve the selectivity and facilitate integration on the transduction platform for sensitive detection. Bacteriophages are one such unique biological entity that show excellent host selectivity and have been actively used as recognition probes for pathogen detection. This review summarizes the extensive literature search on the application of bacteriophages (and recently their receptor binding proteins) as probes for sensitive and selective detection of foodborne pathogens, and critically outlines their advantages and disadvantages over other recognition elements.

  8. Recent Advances in Bacteriophage Based Biosensors for Food-Borne Pathogen Detection

    Directory of Open Access Journals (Sweden)

    Somayyeh Poshtiban

    2013-01-01

    Full Text Available Foodborne diseases are a major health concern that can have severe impact on society and can add tremendous financial burden to our health care systems. Rapid early detection of food contamination is therefore relevant for the containment of food-borne pathogens. Conventional pathogen detection methods, such as microbiological and biochemical identification are time-consuming and laborious, while immunological or nucleic acid-based techniques require extensive sample preparation and are not amenable to miniaturization for on-site detection. Biosensors have shown tremendous promise to overcome these limitations and are being aggressively studied to provide rapid, reliable and sensitive detection platforms for such applications. Novel biological recognition elements are studied to improve the selectivity and facilitate integration on the transduction platform for sensitive detection. Bacteriophages are one such unique biological entity that show excellent host selectivity and have been actively used as recognition probes for pathogen detection. This review summarizes the extensive literature search on the application of bacteriophages (and recently their receptor binding proteins as probes for sensitive and selective detection of foodborne pathogens, and critically outlines their advantages and disadvantages over other recognition elements.

  9. Extending the Bacillus cereus group genomics to putative food-borne pathogens of different toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Goltsman, Eugene [U.S. Department of Energy, Joint Genome Institute; Auger, Sandrine [Genetique Microbienne; Galleron, Nathalie [Genetique Microbienne; Segurens, Beatrice [Center National Sequencage, F-91057 Evry, France; Simon, Jorg [Johann Wolfgang Goethe University, Frankfurt am Main, Germany; Dossat, Carole [Genoscope/Centre National de la Recherche Scientifique-Unite Mixte de Recherche; Land, Miriam L [ORNL; Broussolle, Veronique [Securite et Qualite des Produits d' Origine Vegetale; Brillard, Julien [Securite et Qualite des Produits d' Origine Vegetale; Guinebretiere, Marie-Helene [Securite et Qualite des Produits d' Origine Vegetale; Sanchis, Vincent [Genetique Microbienne; Nguen-the, Christophe [Securite et Qualite des Produits d' Origine Vegetale; Lereclus, Didier [Genetique Microbienne; Richardson, P M [U.S. Department of Energy, Joint Genome Institute; Wincker, Patrick [Genoscope/Centre National de la Recherche Scientifique-Unite Mixte de Recherche; Weissenbach, Jean [Genoscope/Centre National de la Recherche Scientifique-Unite Mixte de Recherche; Ehrlich, Dusko [Genetique Microbienne; Sorokin, Alexei [Genetique Microbienne

    2008-01-01

    The Bacillus cereus group represents sporulating soil bacteria containing pathogenic strains which may cause diarrheic or emetic food poisoning outbreaks. Multiple locus sequence typing revealed a presence in natural samples of these bacteria of about 30 clonal complexes. Application of genomic methods to this group was however biased due to the major interest for representatives closely related to Bacillus anthracis. Albeit the most important food-borne pathogens were not yet defined, existing data indicate that they are scattered all over the phylogenetic tree. The preliminary analysis of the sequences of three genomes discussed in this paper narrows down the gaps in our knowledge of the B. cereus group. The strain NVH391-98 is a rare but particularly severe food-borne pathogen. Sequencing revealed that the strain should be a representative of a novel bacterial species, for which the name Bacillus cytotoxis or Bacillus cytotoxicus is proposed. This strain has a reduced genome size compared to other B. cereus group strains. Genome analysis revealed absence of sigma B factor and the presence of genes encoding diarrheic Nhe toxin, not detected earlier. The strain B. cereus F837/76 represents a clonal complex close to that of B. anthracis. Including F837/76, three such B. cereus strains had been sequenced. Alignment of genomes suggests that B. anthracis is their common ancestor. Since such strains often emerge from clinical cases, they merit a special attention. The third strain, KBAB4, is a typical facultative psychrophile generally found in soil. Phylogenic studies show that in nature it is the most active group in terms of gene exchange. Genomic sequence revealed high presence of extra-chromosomal genetic material (about 530 kb) that may account for this phenomenon. Genes coding Nhe-like toxin were found on a big plasmid in this strain. This may indicate a potential mechanism of toxicity spread from the psychrophile strain community. The results of this genomic

  10. Extreme Heat Resistance of Food Borne Pathogens Campylobacter jejuni, Escherichia coli, and Salmonella typhimurium on Chicken Breast Fillet during Cooking

    DEFF Research Database (Denmark)

    de Jong, Aarieke E I; van Asselt, Esther D; Zwietering, Marcel H;

    2012-01-01

    cooking enlarged the heat resistance of the food borne pathogens. Additionally, a high challenge temperature or fast heating rate contributed to the level of heat resistance. The data were used to assess the probability of illness (campylobacteriosis) due to consumption of chicken fillet as a function...

  11. Complete Genome Sequence of Cronobacter turicensis LMG 23827, a Food-Borne Pathogen Causing Deaths in Neonates ▿

    OpenAIRE

    2010-01-01

    Here, we report the complete and annotated genome sequence of Cronobacter turicensis, an opportunistic food-borne pathogen, which is known as a rare but important cause of life-threatening neonatal infections. Among all proteins of C. turicensis, 223 have been annotated as virulence- and disease-related proteins.

  12. Complete genome sequence of Cronobacter turicensis LMG 23827, a food-borne pathogen causing deaths in neonates.

    Science.gov (United States)

    Stephan, Roger; Lehner, Angelika; Tischler, Patrick; Rattei, Thomas

    2011-01-01

    Here, we report the complete and annotated genome sequence of Cronobacter turicensis, an opportunistic food-borne pathogen, which is known as a rare but important cause of life-threatening neonatal infections. Among all proteins of C. turicensis, 223 have been annotated as virulence- and disease-related proteins.

  13. Top-down proteomic identification of protein biomarkers of food-borne pathogens using MALDI-TOF-TOF-MS/MS

    Science.gov (United States)

    This chapter describes a step-by-step protocol and discussion of top-down proteomic identification of protein biomarkers of food-borne pathogens using matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-TOF-MS/MS) and web-based software developed in the Pro...

  14. Co-infection dynamics of a major food-borne zoonotic pathogen in chicken.

    Directory of Open Access Journals (Sweden)

    Beate Skånseng

    2007-11-01

    Full Text Available A major bottleneck in understanding zoonotic pathogens has been the analysis of pathogen co-infection dynamics. We have addressed this challenge using a novel direct sequencing approach for pathogen quantification in mixed infections. The major zoonotic food-borne pathogen Campylobacter jejuni, with an important reservoir in the gastrointestinal (GI tract of chickens, was used as a model. We investigated the co-colonisation dynamics of seven C. jejuni strains in a chicken GI infection trial. The seven strains were isolated from an epidemiological study showing multiple strain infections at the farm level. We analysed time-series data, following the Campylobacter colonisation, as well as the dominant background flora of chickens. Data were collected from the infection at day 16 until the last sampling point at day 36. Chickens with two different background floras were studied, mature (treated with Broilact, which is a product consisting of bacteria from the intestinal flora of healthy hens and spontaneous. The two treatments resulted in completely different background floras, yet similar Campylobacter colonisation patterns were detected in both groups. This suggests that it is the chicken host and not the background flora that is important in determining the Campylobacter colonisation pattern. Our results showed that mainly two of the seven C. jejuni strains dominated the Campylobacter flora in the chickens, with a shift of the dominating strain during the infection period. We propose a model in which multiple C. jejuni strains can colonise a single host, with the dominant strains being replaced as a consequence of strain-specific immune responses. This model represents a new understanding of C. jejuni epidemiology, with future implications for the development of novel intervention strategies.

  15. Sugar fatty acid esters inhibit biofilm formation by food-borne pathogenic bacteria

    Science.gov (United States)

    Furukawa, Soichi; Akiyoshi, Yuko; O’Toole, George A.; Ogihara, Hirokazu; Morinaga, Yasushi

    2010-01-01

    Effects of food additives on biofilm formation by food-borne pathogenic bacteria were investigated. Thirty-three potential food additives and 3 related compounds were added to the culture medium at concentrations from 0.001 to 0.1% (w/w), followed by inoculation and cultivation of five biofilm-forming bacterial strains for the evaluation of biofilm formation. Among the tested food additives, 21 showed inhibitory effects of biofilm formation by Staphylococcus aureus and Escherichia coli, and in particular, sugar fatty acid esters showed significant anti-biofilm activity. Sugar fatty acid esters with long chain fatty acid residues (C14-16) exerted their inhibitory effect at the concentration of 0.001%(w/w), but bacterial growth was not affected at this low concentration. Activities of the sugar fatty acid esters positively correlated with the increase of the chain length of the fatty acid residues. Sugar fatty acid esters inhibited the initial attachment of the Staphylococcus aureus cells to the abiotic surface. Sugar fatty acid esters with long chain fatty acid residues (C14-16) also inhibited biofilm formation by Streptococcus mutans and Listeria monocytogenes at 0.01%(w/w), while the inhibition of biofilm formation by Pseudomonas aeruginosa required the addition of a far higher concentration (0.1%(w/w)) of the sugar fatty acid esters. PMID:20089325

  16. Sugar fatty acid esters inhibit biofilm formation by food-borne pathogenic bacteria.

    Science.gov (United States)

    Furukawa, Soichi; Akiyoshi, Yuko; O'Toole, George A; Ogihara, Hirokazu; Morinaga, Yasushi

    2010-03-31

    Effects of food additives on biofilm formation by food-borne pathogenic bacteria were investigated. Thirty-three potential food additives and 3 related compounds were added to the culture medium at concentrations from 0.001 to 0.1% (w/w), followed by inoculation and cultivation of five biofilm-forming bacterial strains for the evaluation of biofilm formation. Among the tested food additives, 21 showed inhibitory effects of biofilm formation by Staphylococcus aureus and Escherichia coli, and in particular, sugar fatty acid esters showed significant anti-biofilm activity. Sugar fatty acid esters with long chain fatty acid residues (C14-16) exerted their inhibitory effect at the concentration of 0.001% (w/w), but bacterial growth was not affected at this low concentration. Activities of the sugar fatty acid esters positively correlated with the increase of the chain length of the fatty acid residues. Sugar fatty acid esters inhibited the initial attachment of the S. aureus cells to the abiotic surface. Sugar fatty acid esters with long chain fatty acid residues (C14-16) also inhibited biofilm formation by Streptococcus mutans and Listeria monocytogenes at 0.01% (w/w), while the inhibition of biofilm formation by Pseudomonas aeruginosa required the addition of a far higher concentration (0.1% (w/w)) of the sugar fatty acid esters.

  17. Lactobacillus plantarum strains as a bio-control strategy against food-borne pathogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Mattia Pia Arena

    2016-04-01

    their antimicrobial effect. This study emphasizes the tempting use of the tested L. plantarum strains and/or their CFS as antimicrobial agents against food-borne pathogens.

  18. Genomic paradigms for food-borne enteric pathogen analysis at the USFDA: case studies highlighting method utility, integration and resolution.

    Science.gov (United States)

    Elkins, C A; Kotewicz, M L; Jackson, S A; Lacher, D W; Abu-Ali, G S; Patel, I R

    2013-01-01

    Modern risk control and food safety practices involving food-borne bacterial pathogens are benefiting from new genomic technologies for rapid, yet highly specific, strain characterisations. Within the United States Food and Drug Administration (USFDA) Center for Food Safety and Applied Nutrition (CFSAN), optical genome mapping and DNA microarray genotyping have been used for several years to quickly assess genomic architecture and gene content, respectively, for outbreak strain subtyping and to enhance retrospective trace-back analyses. The application and relative utility of each method varies with outbreak scenario and the suspect pathogen, with comparative analytical power enhanced by database scale and depth. Integration of these two technologies allows high-resolution scrutiny of the genomic landscapes of enteric food-borne pathogens with notable examples including Shiga toxin-producing Escherichia coli (STEC) and Salmonella enterica serovars from a variety of food commodities. Moreover, the recent application of whole genome sequencing technologies to food-borne pathogen outbreaks and surveillance has enhanced resolution to the single nucleotide scale. This new wealth of sequence data will support more refined next-generation custom microarray designs, targeted re-sequencing and "genomic signature recognition" approaches involving a combination of genes and single nucleotide polymorphism detection to distil strain-specific fingerprinting to a minimised scale. This paper examines the utility of microarrays and optical mapping in analysing outbreaks, reviews best practices and the limits of these technologies for pathogen differentiation, and it considers future integration with whole genome sequencing efforts.

  19. Effect of small chain N acyl homoserine lactone quorum sensing signals on biofilms of food-borne pathogens.

    Science.gov (United States)

    A, Jamuna Bai; V, Ravishankar Rai

    2016-09-01

    Quorum sensing or cell to cell communication which includes inter- and intra-cellular communication has been implicated in the production of virulence factor and formation of biofilm in food-borne pathogens. In the present study, the effect of quorum sensing signals on the biofilms of food-borne pathogens has been elucidated. N-butryl homoserine lactone and N-hexanoyl homoserine lactone belonging to acyl homoserine lactone (AHL) family of signaling molecules were investigated for their effect on the biofilm formation (attachment and exopolymeric substance production) in the food-borne pathogens Escherichia coli, Salmonella enterica serovar Typhimurium and Vibrio parahemolyticus. The signaling molecules at a concentration of 1 µM were capable of increasing biofilm formation in all the tested pathogens. There was an increase in the attachment of the bacterial cells and biomass as observed by microtiter plate assay and exopolymeric substances production in the biofilms in presence of the AHLs. Further, it needs to be elucidated if the effect of AHLS on the biofilms of E. coli and S. enterica serovar Typhimurium is SdiA dependent.

  20. Antibacterial potential of Jatropha curcas synthesized silver nanoparticles against food borne pathogens

    Directory of Open Access Journals (Sweden)

    Nitin Chauhan

    2016-11-01

    Full Text Available The aqueous leaf extract of Jatropha curcas was used for the synthesis of silver nanoparticles (Jc-AgNps which were further evaluated for its antibacterial potential against food borne pathogens. J. curcas leaf extract could synthesize stable silver nanoparticles (Zeta potential: -23.4 mV with absorption band at 430 nm. Fourier transform infrared spectroscopy (FTIR indicated various biological compounds responsible for capping and stabilizing Jc-AgNps in suspension, while the presence of silver was authenticated by scanning electron microscopy (SEM equipped with energy-dispersive X-ray (EDX. Jc-AgNps were confirmed to be uniform in shape, size and behaviour through dynamic light scattering (DLS, transmission electron microscopy (TEM, X-ray diffraction (XRD, SEM, and atomic force microscopy (AFM analysis. To investigate the antibacterial activity, disc diffusion and microplate dilution assays were performed and zone of inhibition (ZOI as well as minimum inhibitory/bactericidal concentrations (MIC/MBCs were evaluated against selected bacterial strains. Overall results showed that Escherichia coli (ZOI: 23 mm, MBC: 0.010 mg/ml was the most sensitive organism, whereas Staphylococcus aureus (ZOI: 14.66 mm, MBC: 0.041 mg/ml and Salmonella enterica (ZOI: 16.66 mm, MBC: 0.041 mg/ml were the least sensitive against Jc-AgNps. The detailed microscopic investigations using SEM, TEM and AFM were performed to understand the antibacterial impacts of Jc-AgNps against Listeria monocytogenes. SEM and TEM analysis showed the clear deformation and disintegration of treated L. monocytogenes cells, whereas AFM established a decrease in the height and cell surface roughness (RMS value in the treated L. monocytogenes.

  1. Antibacterial Effects of (Mentha X Piperita L. Hydroalcoholic Extract on the Six Food-Borne Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    H Zandi

    2016-11-01

    Full Text Available Abstract Introduction: Iran is the richest country in terms of distribution of medicinal plants. The antimicrobial effect of plant extracts and essential oils is well known and they are used as a good substitute in food industry to control food-borne pathogens. Due to the antibacterial activity of plant extracts and their efficacy against microorganisms, the aim of this study was to investigate the antibacterial activity of peppermint extract in order to control pathogenic bacteria. Methods: Piperita L., which is one of the species of mint; was used in this invitro-experimental study. The extraction was performed by percolation method. Well - agar method was used for antibacterial effects of extracts. The minimum inhibitory concentration (MIC and minimal bactericidal concentration (MBC were done for six standard bacteria using microdilution method. The test was performed 3 times for each bacterium. Data were analyzed by using SPSS version 16 and t-test. Results: The lowest MIC of peppermint extract on examined microorganisms were observed for Staphylococcus aureus and Enterococcus faecalis (3.25 mg/ ml. Also the maximum diameter of inhibition zone, was related to Staphylococcus aureus (32 mm. Conclusion: Results of this study indicated that peppermint extract has a favorable control effect on the growth of food borne pathogens, which can be used as a perfect preservative for keeping food.

  2. Interaction between Food-borne Pathogens (Campylobacter jejuni, Salmonella Typhimurium and Listeria monocytogenes) and a Common Soil Flagellate (Cercomonas sp.)

    DEFF Research Database (Denmark)

    Bui, Thanh Xuan; Wolff, Anders; Madsen, Mogens

    2012-01-01

    Free-living protozoa may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. The flagellates are very important predators on bacteria in soil, but their role in the survival of food-borne pathogens associated with fruits and vegetables is not well...... understood. In this study, we investigated the interactions between a common soil flagellate, Cercomonas sp., and three different bacterial pathogens (Campylobacter jejuni, Salmonella Typhimurium, and Listeria monocytogenes). Rapid growth of flagellates was observed in co-culture with C. jejuni and S....... Typhimurium over the time course of 15 days. In contrast, the number of Cercomonas sp. cells decreased when grown with or without L. monocytogenes for 9 days of co-culture. Interestingly, we observed that C. jejuni and S. Typhimurium survived better when co-cultured with flagellates than when cultured alone...

  3. [Investigation of pathogenic phenotypes and virulence determinants of food-borne Salmonella enterica strains in Caenorhabditis elegans animal model].

    Science.gov (United States)

    Aksoy, Deniz; Şen, Ece

    2015-10-01

    Salmonellosis, caused by non-typhoidal Salmonella enterica serovars with the consumption of contaminated food, is one of the leading food-borne disease that makes microbial food safety an important public health issue. This study was performed in order to determine the antibiotic resistance, serotyping, plasmid profiles and pathogenicity potentials of food-borne Salmonella isolates in Caenorhabditis elegans animal model system in Edirne province, located at Thrace region of Turkey. In this study, 32 Salmonella isolates, of which 26 belonged to Infantis, four to Enteritidis, one to Telaviv and one to Kentucky serovars, isolated from chicken carcasses were used. Antibiotic resistance profiles were determined by disc diffusion and broth microdilution methods. A new C.elegans nematode animal model system was used to determine the pathogenicity potential of the isolates. The antibiotic resistance profiles revealed that one (3.1%) isolate was resistant to gentamicin, two (6.2%) to ciprofloxacin, three (9.4%) to ampicillin, 18 (56.3%) to kanamycin, 19 (60.8%) to neomycin, 25 (78.1%) to tetracycline, 25 (78.1%) to trimethoprim, 26 (81.25%) to nalidixic acid, 27 (84.4%) to streptomycin and 32 (100%) to sulfonamide. All of the 32 strains were susceptible to chloramphenicol and ampicillin/sulbactam. High levels of resistance to streptomycin, nalidixic acid, tetracycline, trimethoprim, sulfonamide, kanamycin and neomycin was determined. According to the plasmid analysis, six isolates (18.75%) harboured 1-3 plasmids with sizes between 1.2 and 42.4 kb. In C.elegans nematode animal model system, the time (in days) required to kill 50% (TD50) of nematodes was calculated for each experimental group. TD50 values of the nematode group fed with S.Typhimurium ATCC 14028 that was used as the positive control and another group fed with E.coli OP50 as the negative control were 4.2 ± 0.5 days and 8.0 ± 0.02 days, respectively. TD50 of the groups fed with Salmonella isolates ranged

  4. Simultaneous, specific and real-time detection of biothreat and frequently encountered food-borne pathogens

    Science.gov (United States)

    Woubit, Abdela Salah; Yehualaeshet, Teshome; Habtemariam, Tsegaye; Samuel, Temesgen

    2012-01-01

    The bacterial genera Escherichia, Salmonella, Shigella, Vibrio, Yersinia and Francisella include important food safety and biothreat agents causing food-related and other human illnesses worldwide. We aimed to develop rapid methods with the capability to simultaneously and differentially detect all six pathogens in one run. Our initial experiments to use previously reported sets of primers revealed non-specificity of some of the sequences when tested against a broader array of pathogens, or proved not optimal for simultaneous detection parameters. By extensive mining of the whole genome and protein databases of diverse closely and distantly related bacterial species and strains, we have identified unique genome regions, which we utilized to develop a detection platform. Twelve of the specific genomic targets we have identified to design the primers in F. tularensis ssp. tularensis, F. tularensis ssp. novicida, S. dysentriae, S. typhimurium, V. cholera, Y. pestis, and Y. pseudotuberculosis contained either hypothetical or putative proteins, the functions of which have not been clearly defined. Corresponding primer sets were designed from the target regions for use in real-time PCR assays to detect specific biothreat pathogens at species or strain levels. The primer sets were first tested by in-silico PCR against whole genome sequences of different species, sub-species, or strains and then by in vitro PCR against genomic DNA preparations from 23 strains representing six biothreat agents (E.coli O157:H7 strain EDL 933, Shigella dysentriae, Salmonella typhi, Francisella tularensis ssp. tularensis, Vibrio cholera, and Yersinia pestis) and six foodborne pathogens (Salmonella typhimurium, Salmonella saintpaul, Shigella sonnei, Francisella novicida, Vibrio parahemolytica and Yersinia pseudotuberculosis). Each pathogen was specifically identifiable at the genus and species levels. Sensitivity assays performed using purified DNA showed the lowest detection limit of 640 fg

  5. Inhibition Effect of Lactic Acid Bacteria against Food Born Pathogen, Listeria monocytogenes

    Directory of Open Access Journals (Sweden)

    Rouha Kasra-Kermanshahi

    2015-09-01

    Full Text Available Disease caused by consuming microbial contaminated food has increased significantly in recent years due to changes in the livelihoods and eating habits of the human populations. Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica are three of the most important foodborne bacterial pathogens and can lead to foodborne diseases. Increased use of antibiotics, has led to development of bacterial resistance to antibiotics. Therefore, there is growing interest in the development of new types of effective and nontoxic antimicrobial compounds. Nowadays, the most extensive research and commercial practices are based on probiotic bacteria. Probiotics, specifically lactic acid bacteria are widely used in the food industry for fermentation but have gained attention from health professionals because of their potential beneficial effects. Now probiotic therapy is thought to be an effective way to improve the gut health and an alternative to antibiotic treatments. They contribute to food safety by their ability to inhibit the growth of several other bacteria. LAB can be used as protective cultures to compete with potential pathogens and other undesired organisms, thereby increasing the safety of the food product.

  6. Antimicrobial Activity of the Essential Oil from the Leaves and Seeds of Coriandrum sativum toward Food-borne Pathogens.

    Science.gov (United States)

    Rezaei, M; Karimi, F; Shariatifar, N; Mohammadpourfard, I; Malekabad, E S

    2015-06-03

    The increasing incidence of drug-resistant pathogens and toxicity of existing antibacterial compounds has drawn attention toward the antimicrobial activity of natural products. The purpose of this study is to evaluate the antimicrobial activity of the essential oil of the leaves and seeds of Coriandrum sativum. The five strains of bacteria comprising Escherichia coli, Staphylococcus aureus, Yersinia enterocolitica, Salmonella enterica and Vibrio cholera were used for the antibacterial tests. In this study, antimicrobial effects of the essential oil from the leaves and seeds of Coriandrum sativum were evaluated by determining the minimum inhibitory concentration (MIC), the inhibition zone and minimum bacteria concentration (MBC). The essential oil from Coriandrum sativum was extracted by steam distillation. The results indicate that the antimicrobial activities against the five pathogens were in the range of 2.5-320 µg/mL. Therefore, an increase in essential oil concentration caused significant increase in inhibitory feature. The essential oil from the leaves and seeds of Coriandrum sativum showed antimicrobial activity against the food-borne pathogenic bacteria. Thus, its oil can be used as an alternative to synthetic food preservative without toxic effects. Also, the oil can be used in biotechnological fields as ingredients in antibiotics and the pharmaceutical industry. These results suggest that the essential oil of C sativum leaves and seeds may have potential use in pharmaceutical and food industries for preservatives or antimicrobial agents.

  7. ANTIBACTERIAL ACTIVITY OF GUAVA (PSIDIUM GUAJAVA L.) AND NEEM (AZADIRACHTA INDICA A. JUSS.)EXTRACTS AGAINST FOOD BORNE PATHOGENS AND SPOILAGE BACTERIA

    Science.gov (United States)

    The objective of this study was to investigate the antibacterial properties of guava (Psidium guajava) and neem (Azadirachta indica) extracts against a number of common food borne pathogens and spoilage bacteria. Screening for antibacterial activity was determined by disc diffusion assay against 21...

  8. Detection of food-borne pathogens by nanoparticle technology coupled to a low-cost cell reader

    Science.gov (United States)

    Noiseux, Isabelle; Bouchard, Jean-Pierre; Gallant, Pascal; Bourqui, Pascal; Cao, Honghe; Vernon, Marci; Johnson, Roger; Chen, Shu; Mermut, Ozzy

    2010-02-01

    The detection, identification and quantification of pathogenic microorganisms at low cost are of great interest to the agro-food industry. We have developed a simple, rapid, sensitive, and specific method for detection of food-borne pathogens based on use of nanoparticles alongside a low cost fluorescence cell reader for the bioassay. The nanoparticles are coupled with antibodies that allow specific recognition of the targeted Listeria in either a liquid or food matrix. The bioconjugated nanoparticles (FNP) contain thousands of dye molecules enabling significant amplification of the fluorescent signal emitted from each bacterium. The developed fluorescence Cell Reader is an LED-based reader coupled with suitable optics and a camera that acquires high resolution images. The dedicated algorithm allowed the counting of each individual nanoparticles-fluorescent bacterial cells thus enabling highly sensitive reading. The system allows, within 1 hour, the recovery and counting of 104 to 108 cfu/mL of Listeria in pure culture. However, neither the Cell Reader nor the algorithm can differentiate between the FNPs specifically-bound to the target and the residual unbound FNPs limiting sensitivity of the system. Since FNPs are too small to be washed in the bioassay, a dual tagging approach was implemented to allow online optical separation of the fluorescent background caused by free FNPs.

  9. The adaptive response of bacterial food-borne pathogens in the environment, host and food: Implications for food safety.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Broussolle, Véronique; Colin, Pierre; Nguyen-The, Christophe; Prieto, Miguel

    2015-11-20

    Bacteria are constantly faced to stress situations in their ecological niches, the food and the host gastrointestinal tract. The capacity to detect and respond to surrounding changes is crucial for bacterial pathogens to survive or grow in changing environments. To this purpose, cells have evolved various sophisticated networks designed to protect against stressors or repair damage caused by them. Challenges can occur during production of foods when subjected to processing, and after food ingestion when confronted with host defensive barriers. Some pathogenic bacteria have shown the capacity to develop stable resistance against extreme conditions within a defined genomic context and a limited number of generations. On the other hand, bacteria can also respond to adverse conditions in a transient manner, through the so-called stress tolerance responses. Bacterial stress tolerance responses include both structural and physiological modifications in the cell and are mediated by complex genetic regulatory machinery. Major aspects in the adaptive response are the sensing mechanisms, the characterization of cell defensive systems, such as the operation of regulatory proteins (e.g. RpoS), the induction of homeostatic and repair systems, the synthesis of shock response proteins, and the modifications of cell membranes, particularly in their fatty acid composition and physical properties. This article reviews certain strategies used by food-borne bacteria to respond to particular stresses (acid, cold stress, extreme pressure) in a permanent or transient manner and discusses the implications that such adaptive responses pose for food safety.

  10. Research Progress on Rapid Detection of Food-Borne Bacterial Pathogens%食源性致病菌快速检测技术研究进展

    Institute of Scientific and Technical Information of China (English)

    封莉; 黄继超; 刘欣; 黄明; 周光宏

    2012-01-01

    食源性致病菌是引发食源性疾病的主要因素,如何有效地检测出食源性致病菌的存在是食源性疾病预防与控制的关键环节。本文较为系统地介绍了利用免疫学、代谢学、分子生物学和生物传感器等技术手段快速检测食源性致病菌的方法,其中免疫学技术由于快速简便和低操作要求等特点便于目前的普及,而分子生物学方法则是致病菌检测的主要发展方向。%Food-borne diseases are mainly caused by bacterial pathogens present in foods.How to effectively detect food-borne bacterial pathogens is the key to prevent and control food-borne disease.This systematic review describes immunological,metabolomics,molecular biological and biosensor techniques for rapid detection of food-borne bacterial pathogens.Immunological techniques are currently very popular due to rapidity,simplicity and low operating requirements.But molecular biological techniques are the main development direction.

  11. Assessment of a regulatory sanitization process in Egyptian dairy plants in regard to the adherence of some food-borne pathogens and their biofilms.

    Science.gov (United States)

    Bayoumi, Mohamed A; Kamal, Rania M; Abd El Aal, Salah F; Awad, Esmat I

    2012-09-03

    Food-borne pathogens may develop certain strategies that enable them to defy harsh conditions such as chemical sanitization. Biofilm formation represents a prominent one among those adopted strategies, by which food-borne pathogens protect themselves against external threats. Thus, bacterial biofilm is considered as a major hazard for safe food production. This study was designed to investigate the adherence and the biofilm formation ability of some food-borne pathogens on stainless steel and polypropylene surfaces using chip assay, and to validate regular sanitizing process (sodium hypochlorite 250 mg/L) for effective elimination of those pathogens. Sixteen pathogenic bacterial strains, previously isolated from raw milk and dairy products at Zagazig city, Egypt (9 Staphylococcus aureus, 4 Cronobacter sakazakii and 3 Salmonella enterica serovar Typhimurium), were chosen for this study. Strains showed different patterns of adherence and biofilm formation on tested surfaces with minor significance between surfaces. The ability of sodium hypochlorite to completely eradicate either adhered or biofilm-embedded pathogens varied significantly depending on the strain and type of surface used. Whilst, sodium hypochlorite reduced tested pathogens counts per cm² of produced biofilms, but it was not able to entirely eliminate neither them nor adherent Cronobacter sakazakii to stainless steel surface. This study revealed that biofilm is considered as a sustainable source of contamination of dairy products with these pathogens, and also emphasized the need of paying more attention to the cleaning and sanitizing processes of food contact surfaces.

  12. Cold Plasma as a novel intervention against food-borne pathogens

    Science.gov (United States)

    Contamination of meats, seafood, fresh and fresh-cut fruits and vegetables and other foods by foodborne pathogens has prompted research into novel interventions. Cold plasma is a nonthermal food processing technology which uses energetic, reactive gases to inactivate contaminating microbes. This fle...

  13. Piecewise linear approximations to model the dynamics of adaptation to osmotic stress by food-borne pathogens.

    Science.gov (United States)

    Métris, Aline; George, Susie M; Ropers, Delphine

    2017-01-02

    Addition of salt to food is one of the most ancient and most common methods of food preservation. However, little is known of how bacterial cells adapt to such conditions. We propose to use piecewise linear approximations to model the regulatory adaptation of Escherichiacoli to osmotic stress. We apply the method to eight selected genes representing the functions known to be at play during osmotic adaptation. The network is centred on the general stress response factor, sigma S, and also includes a module representing the catabolic repressor CRP-cAMP. Glutamate, potassium and supercoiling are combined to represent the intracellular regulatory signal during osmotic stress induced by salt. The output is a module where growth is represented by the concentration of stable RNAs and the transcription of the osmotic gene osmY. The time course of gene expression of transport of osmoprotectant represented by the symporter proP and of the osmY is successfully reproduced by the network. The behaviour of the rpoS mutant predicted by the model is in agreement with experimental data. We discuss the application of the model to food-borne pathogens such as Salmonella; although the genes considered have orthologs, it seems that supercoiling is not regulated in the same way. The model is limited to a few selected genes, but the regulatory interactions are numerous and span different time scales. In addition, they seem to be condition specific: the links that are important during the transition from exponential to stationary phase are not all needed during osmotic stress. This model is one of the first steps towards modelling adaptation to stress in food safety and has scope to be extended to other genes and pathways, other stresses relevant to the food industry, and food-borne pathogens. The method offers a good compromise between systems of ordinary differential equations, which would be unmanageable because of the size of the system and for which insufficient data are available

  14. 2013年沈阳市食源性致病菌监测分析%Analysis of food borne pathogenic bacteria monitoring in Shenyang city in 2013

    Institute of Scientific and Technical Information of China (English)

    温立海; 赵常志; 刘漪

    2016-01-01

    目的:为了了解沈阳市食源性致病菌污染情况,研究食源性疾病的发生规律,预警食物中毒提供依据。方法:依据国家食源性疾病监测2013年度工作手册,对样品进行检测。结果:共监测乳及乳制品、速冻发面制品、肉及肉制品、水产品等9类样品235份,检出食源性致病菌22份,总检出率9.36%。检出的致病菌分别是金黄色葡萄球菌6株,蜡样芽孢杆菌6株,副溶血性弧菌10株。结论:2013年沈阳市食品存在食源性致病菌污染,应加强本地区食源性致病菌的监测,防止食源性疾病和食物中毒发生。%Objective:In order to understand the pollution situation of food borne pathogenic bacteria in Shenyang City,to study the occurrence regularity of food borne diseases,and to provide evidence for early warning of food poisoning.Methods:According to the national food borne disease monitoring 2013 annual working manual,the samples were detected.Results:235 cases of milk and dairy products,frozen dough products,meat and meat products,aquatic products and so on 9 kinds of samples were monitored,22 food borne pathogenic bacterias were detected,the total detection rate was 9.36%.The detection of pathogenic bacteria were 6 strains of staphylococcus aureus,6 strains of bacillus cereus,10 strains of vibrio parahaemolyticus.Conclusion:In 2013,the food in Shenyang city is contaminated by food borne pathogenic bacteria,which should strengthen the monitoring of food borne pathogenic bacteria in the region to prevent the occurrence of food borne diseases and food poisoning.

  15. Proteomic profiling of Cronobacter turicensis 3032, a food-borne opportunistic pathogen.

    Science.gov (United States)

    Carranza, Paula; Hartmann, Isabel; Lehner, Angelika; Stephan, Roger; Gehrig, Peter; Grossmann, Jonas; Barkow-Oesterreicher, Simon; Roschitzki, Bernd; Eberl, Leo; Riedel, Kathrin

    2009-07-01

    Members of the genus Cronobacter are opportunistic pathogens for neonates and are often associated with contaminated milk powder formulas. At present little is known about the virulence mechanisms or the natural reservoir of these organisms. The proteome of Cronobacter turicensis 3032, which has recently caused two deaths, was mapped aiming at a better understanding of physiology and putative pathogenic traits of this clinical isolate. Our analyses of extracellular, surface-associated and whole-cell proteins by two complementary proteomics approaches, 1D-SDS-PAGE combined with LC-ESI-MS/MS and 2D-LC-MALDI-TOF/TOF MS, lead to the identification of 832 proteins corresponding to a remarkable 19% of the theoretically expressed protein complement of C. turicensis. The majority of the identified proteins are involved in central metabolic pathways, translation, protein folding and stability. Several putative virulence factors, whose expressions were confirmed by phenotypic assays, could be identified: a macrophage infectivity potentiator involved in C. turicensis persistence in host cells, a superoxide dismutase protecting the pathogen against reactive oxygen species and an enterobactin-receptor protein for the uptake of siderophore-bound iron. Most interestingly, a chitinase and a metalloprotease that might act against insects and fungi but no casein hydrolysing enzymes were found, suggesting that there is an environmental natural habitat of C. turicensis 3032.

  16. Food-borne trematode infections of humans in the United States of America.

    Science.gov (United States)

    Fried, Bernard; Abruzzi, Amy

    2010-05-01

    This review examines the literature on imported (allochthonous) and local (autochthonous) cases of food-borne trematode (FBT) infections in the United States of America (USA) from 1890 to 2009. Most of the literature is concerned with imported cases of the opisthorchiids Clonorchis sinensis and Opisthorchis viverrini. These flukes cause serious pathology in the liver and biliary system of humans. Chronic cases may induce liver (hepatocarcinoma) and bile duct (cholangiocarcinoma) cancers in humans. Clonorchiasis and opithorchiasis are preventable diseases that can be avoided by eating properly cooked freshwater fish products. Several species of lung flukes in the genus Paragonimus are local or imported FBT in the USA. The endemic cycle occurs in the USA with various local snails and crustaceans serving as intermediate hosts. Paragonimids are acquired when humans eat raw or improperly cooked freshwater crustaceans containing metacercarial cysts. Infection can cause severe lung disease and the symptoms of paragonimiasis often mimic those of tuberculosis and other non-helminthic diseases. Paragonimiasis can be avoided by not eating raw or improperly cooked shellfish. The liver fluke Fasciola hepatica can be acquired by eating raw or uncooked vegetation. The cycle exists in the USA involving local snails and aquatic vegetation. Although some cases are local, most are imported by travelers or immigrants. Fascioliasis can cause serious liver and biliary diseases in humans and consumption of tainted vegetation should be avoided. Lesser known FBT have been reported in the USA including species of Alaria, echinostomids, heterophyids, troglotrematids, and a self-induced infection of Plagiorchis. Treatment of the FBT mentioned in this review consists of various regimens of praziquantel, except for F. hepatica where the drug of choice is triclabendazole.

  17. Antibacterial Activity of Fructus forsythia Essential Oil and the Application of EO-Loaded Nanoparticles to Food-Borne Pathogens

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    Na Guo

    2016-10-01

    Full Text Available Fructus forsythia essential oil (FEO with excellent antibacterial activity was rarely reported. The objective of the present study was to investigate the antibacterial activity and the antibacterial mechanism of FEO against two food-borne pathogenic bacteria, Escherichia coli (E. coli and Staphylococcus aureus (S. aureus in vitro. When treated FEO, the zones of inhibition (ZOI of E. coli (20.5 ± 0.25 mm and S. aureus (24.3 ± 0.21 mm were much larger than control (p < 0.05. The minimum inhibitory concentrations (MICs of FEO were 3.13 mg/mL and 1.56 mg/mL for E. coli and S. aureus, respectively. The antibacterial mechanism of FEO against E. coil was due to the changes in permeability and integrity of cell membrane leading to the leakage of nucleic acids and proteins. With the superior antibacterial activity of FEO, the nano-encapsulation method has been applied in FEO. When compared to FEO and blank chitosan nanoparticles, FEO-loaded nanoparticles (chitosan to FEO of 1:1 can effectively inhibit the growth of E. coil above 90% at room temperature. It is necessary to consider that FEO and FEO-loaded nanoparticles will become promising antibacterial additives for food preservative, cosmetic, and pharmaceutical applications.

  18. Antibacterial Activity of Fructus forsythia Essential Oil and the Application of EO-Loaded Nanoparticles to Food-Borne Pathogens

    Science.gov (United States)

    Guo, Na; Gai, Qing-Yan; Jiao, Jiao; Wang, Wei; Zu, Yuan-Gang; Fu, Yu-Jie

    2016-01-01

    Fructus forsythia essential oil (FEO) with excellent antibacterial activity was rarely reported. The objective of the present study was to investigate the antibacterial activity and the antibacterial mechanism of FEO against two food-borne pathogenic bacteria, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in vitro. When treated FEO, the zones of inhibition (ZOI) of E. coli (20.5 ± 0.25 mm) and S. aureus (24.3 ± 0.21 mm) were much larger than control (p antibacterial mechanism of FEO against E. coil was due to the changes in permeability and integrity of cell membrane leading to the leakage of nucleic acids and proteins. With the superior antibacterial activity of FEO, the nano-encapsulation method has been applied in FEO. When compared to FEO and blank chitosan nanoparticles, FEO-loaded nanoparticles (chitosan to FEO of 1:1) can effectively inhibit the growth of E. coil above 90% at room temperature. It is necessary to consider that FEO and FEO-loaded nanoparticles will become promising antibacterial additives for food preservative, cosmetic, and pharmaceutical applications.

  19. Proposed mechanism of antibacterial mode of action of Caesalpinia bonducella seed oil against food-borne pathogens

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    Shruti Shukla

    2016-03-01

    Full Text Available The antibacterial mechanism of action of Caesalpinia bonducella seed oil on membrane permeability of Listeria monocytogenes NCIM 24563 (MIC: 2 mg/mL and Escherichia coli ATCC 25922 (MIC: 4 mg/mL was determined by measuring the extracellular ATP concentration, release of 260-nm absorbing materials, leakage of potassium ions and measurement of relative electrical conductivity of the bacterial cells treated at MIC concentration. Its mode of action on membrane integrity was confirmed by release of extracellular ATP (1.42 and 1.33 pg/mL, loss of 260-nm absorbing materials (4.36 and 4.19 optical density, leakage of potassium ions (950 and 1000 mmol/L and increase in relative electrical conductivity (12.6 and 10.5% against food-borne pathogenic bacteria L. monocytogenes and E. coli, respectively. These findings propose that C. bonducella oil compromised its mode of action on membrane integrity, suggesting its enormous food and pharmacological potential.

  20. Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria.

    Science.gov (United States)

    Mith, Hasika; Duré, Rémi; Delcenserie, Véronique; Zhiri, Abdesselam; Daube, Georges; Clinquart, Antoine

    2014-07-01

    This study was undertaken to determine the in vitro antimicrobial activities of 15 commercial essential oils and their main components in order to pre-select candidates for potential application in highly perishable food preservation. The antibacterial effects against food-borne pathogenic bacteria (Listeria monocytogenes, Salmonella Typhimurium, and enterohemorrhagic Escherichia coli O157:H7) and food spoilage bacteria (Brochothrix thermosphacta and Pseudomonas fluorescens) were tested using paper disk diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Most of the tested essential oils exhibited antimicrobial activity against all tested bacteria, except galangal oil. The essential oils of cinnamon, oregano, and thyme showed strong antimicrobial activities with MIC ≥ 0.125 μL/mL and MBC ≥ 0.25 μL/mL. Among tested bacteria, P. fluorescens was the most resistant to selected essential oils with MICs and MBCs of 1 μL/mL. The results suggest that the activity of the essential oils of cinnamon, oregano, thyme, and clove can be attributed to the existence mostly of cinnamaldehyde, carvacrol, thymol, and eugenol, which appear to possess similar activities against all the tested bacteria. These materials could be served as an important natural alternative to prevent bacterial growth in food products.

  1. Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria

    Science.gov (United States)

    Mith, Hasika; Duré, Rémi; Delcenserie, Véronique; Zhiri, Abdesselam; Daube, Georges; Clinquart, Antoine

    2014-01-01

    This study was undertaken to determine the in vitro antimicrobial activities of 15 commercial essential oils and their main components in order to pre-select candidates for potential application in highly perishable food preservation. The antibacterial effects against food-borne pathogenic bacteria (Listeria monocytogenes, Salmonella Typhimurium, and enterohemorrhagic Escherichia coli O157:H7) and food spoilage bacteria (Brochothrix thermosphacta and Pseudomonas fluorescens) were tested using paper disk diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Most of the tested essential oils exhibited antimicrobial activity against all tested bacteria, except galangal oil. The essential oils of cinnamon, oregano, and thyme showed strong antimicrobial activities with MIC ≥ 0.125 μL/mL and MBC ≥ 0.25 μL/mL. Among tested bacteria, P. fluorescens was the most resistant to selected essential oils with MICs and MBCs of 1 μL/mL. The results suggest that the activity of the essential oils of cinnamon, oregano, thyme, and clove can be attributed to the existence mostly of cinnamaldehyde, carvacrol, thymol, and eugenol, which appear to possess similar activities against all the tested bacteria. These materials could be served as an important natural alternative to prevent bacterial growth in food products. PMID:25473498

  2. Chemical Composition and In Vitro Antibacterial Activity of Mentha spicata Essential Oil against Common Food-Borne Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    Yasser Shahbazi

    2015-01-01

    Full Text Available The aim of the present study was to investigate chemical composition and antibacterial activity of essential oil from the leaf of Mentha spicata plant against common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7. Chemical composition of the essential oil was identified by gas chromatography coupled with mass spectrometer detector (GC-MS. The antibacterial activity of the essential oil was evaluated by broth microdilution method and agar disk diffusion assay. According to the result of GC-MS analysis, 18 components were identified, accounting for 99.89% of the whole essential oil. The main components were carvone (78.76%, limonene (11.50%, β-bourbonene (11.23%, cis-dihydrocarveol (1.43%, trans-caryophyllene (1.04%, menthone (1.01%, menthol (1%, and terpinen-4-ol (0.99. The essential oil exhibited moderate level of antibacterial activity against all test microorganisms. In general, Gram-positive bacteria were more susceptible to M. spicata essential oil than Gram-negative bacteria. L. monocytogenes was the most sensitive of the microorganisms to the antibacterial activity of M. spicata essential oil (inhibition zone = 22 mm and MIC and MBC = 2.5 µL/mL. Based on our results, the essential oil of M. spicata plant collected from Kermanshah province, west of Iran, has a potential to be applied as antibacterial agent.

  3. Chemical Composition and In Vitro Antibacterial Activity of Mentha spicata Essential Oil against Common Food-Borne Pathogenic Bacteria.

    Science.gov (United States)

    Shahbazi, Yasser

    2015-01-01

    The aim of the present study was to investigate chemical composition and antibacterial activity of essential oil from the leaf of Mentha spicata plant against common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7). Chemical composition of the essential oil was identified by gas chromatography coupled with mass spectrometer detector (GC-MS). The antibacterial activity of the essential oil was evaluated by broth microdilution method and agar disk diffusion assay. According to the result of GC-MS analysis, 18 components were identified, accounting for 99.89% of the whole essential oil. The main components were carvone (78.76%), limonene (11.50%), β-bourbonene (11.23%), cis-dihydrocarveol (1.43%), trans-caryophyllene (1.04%), menthone (1.01%), menthol (1%), and terpinen-4-ol (0.99). The essential oil exhibited moderate level of antibacterial activity against all test microorganisms. In general, Gram-positive bacteria were more susceptible to M. spicata essential oil than Gram-negative bacteria. L. monocytogenes was the most sensitive of the microorganisms to the antibacterial activity of M. spicata essential oil (inhibition zone = 22 mm and MIC and MBC = 2.5 µL/mL). Based on our results, the essential oil of M. spicata plant collected from Kermanshah province, west of Iran, has a potential to be applied as antibacterial agent.

  4. Use of Lactobacillus plantarum Strains as a Bio-Control Strategy against Food-Borne Pathogenic Microorganisms

    Science.gov (United States)

    Arena, Mattia Pia; Silvain, Amandine; Normanno, Giovanni; Grieco, Francesco; Drider, Djamel; Spano, Giuseppe; Fiocco, Daniela

    2016-01-01

    . This study emphasizes the tempting use of the tested L. plantarum strains and/or their CFS as antimicrobial agents against food-borne pathogens. PMID:27148172

  5. Use of Lactobacillus plantarum Strains as a Bio-Control Strategy against Food-Borne Pathogenic Microorganisms.

    Science.gov (United States)

    Arena, Mattia Pia; Silvain, Amandine; Normanno, Giovanni; Grieco, Francesco; Drider, Djamel; Spano, Giuseppe; Fiocco, Daniela

    2016-01-01

    . This study emphasizes the tempting use of the tested L. plantarum strains and/or their CFS as antimicrobial agents against food-borne pathogens.

  6. Prevalence of the main food-borne pathogens in retail food under the national food surveillance system in Japan.

    Science.gov (United States)

    Hara-Kudo, Y; Konuma, H; Kamata, Y; Miyahara, M; Takatori, K; Onoue, Y; Sugita-Konishi, Y; Ohnishi, T

    2013-01-01

    The National Food Surveillance System in Japan was formed in 1998 to monitor the contamination of retail foods with bacterial pathogens. Approximately 2000-3000 samples were tested annually, and the data from food categories that had more than 400 samples collected during 1998-2008 were analysed. With regard to meat, the frequency of positive samples for Salmonella in chicken for raw consumption and ground chicken was 12.7% and 33.5%, respectively. Moreover, Shiga toxin-producing Escherichia coli (STEC) O157 was found in ground meat, organ meat and processed meat, although at a low frequency (0.1%). The prevalence of Campylobacter jejuni/coli was 13.3% and 20.9% in chicken for raw consumption and ground chicken, respectively. In vegetables and fruit, Salmonella was detected in cucumber, lettuce, sprout and tomato samples at a frequency of around 0.1-0.2%. With regard to seafood, Salmonella was found in 0.5% of oysters for raw consumption. Seafood was not contaminated with STEC O157 or Shigella. Serotype Infantis was the most frequently detected serotype of Salmonella in seafood, followed by the serotypes Typhimurium, Schwarzengrund and Manhattan. In ground chicken, 72.2% of the strains were identified as the serotype Infantis. E. coli, as an indicator of food hygiene, was detected in all food categories. The results show the prevalence of the above-mentioned pathogens in the retail food supplied in Japan; further, they indicate that consumption of raw food carries the risk of contracting food-borne infections.

  7. A gel-free quantitative proteomics approach to investigate temperature adaptation of the food-borne pathogen Cronobacter turicensis 3032.

    Science.gov (United States)

    Carranza, Paula; Grunau, Alexander; Schneider, Thomas; Hartmann, Isabel; Lehner, Angelika; Stephan, Roger; Gehrig, Peter; Grossmann, Jonas; Groebel, Katrin; Hoelzle, Ludwig E; Eberl, Leo; Riedel, Kathrin

    2010-09-01

    The opportunistic food-borne pathogen Cronobacter sp. causes rare but significant illness in neonates and is capable to grow at a remarkably wide range of temperatures from 5.5 to 47 degrees C. A gel-free quantitative proteomics approach was employed to investigate the molecular basis of the Cronobacter sp. adaptation to heat and cold-stress. To this end the model strain Cronobacter turicensis 3032 was grown at 25, 37, 44, and 47 degrees C, and whole-cell and secreted proteins were iTRAQ-labelled and identified/quantified by 2-D-LC-MALDI-TOF/TOF-MS. While 44 degrees C caused only minor changes in C. turicensis growth rate and protein profile, 47 degrees C affected the expression of about 20% of all 891 identified proteins and resulted in a reduced growth rate and rendered the strain non-motile and filamentous. Among the heat-induced proteins were heat shock factors, transcriptional and translational proteins, whereas proteins affecting cellular morphology, proteins involved in motility, central metabolism and energy production were down-regulated. Notably, numerous potential virulence factors were found to be up-regulated at higher temperatures, suggesting an elevated pathogenic potential of Cronobacter sp. under these growth conditions. Significant alterations in the protein expression profile and growth rate of C. turicensis exposed to 25 degrees C indicate that at this temperature the organism is cold-stressed. Up-regulated gene products comprised cold-shock, DNA-binding and ribosomal proteins, factors that support protein folding and proteins opposing cold-induced decrease in membrane fluidity, whereas down-regulated proteins were mainly involved in central metabolism.

  8. In Vitro Evaluation of the Antibiogramic Activities of the Seeds of Myristica fragrans on Food Borne Pathogens

    Directory of Open Access Journals (Sweden)

    Emefo, O. T.

    2012-01-01

    Full Text Available Aims: Foodborne diseases have been shown to have direct impact on the health and welfare of a large number of the world population. The in vitro antibiogramic properties of natural spices (Myristica fragrans on common food borne pathogen became necessary both in improving food safety and development of new drugs. Methodology and Results: Test isolates (Staphylococcus aureus, S. epidermidis, Klebsiella pneumoniae, Bacillus cereus, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa were collected from the culture collection unit of the department of Microbiology, Benson Idahosa University, Nigeria. Seeds of M. fragrans were extracted by soxhlet extractor using ethanol and water, while the oil was obtained by steam distillation. The extracts and oil were tested against the bacterial isolates using agar well diffusion method at varying concentration (12.5, 25, 50 and 100 mg/mL. The oil of M. fragrans was found to have the highest antibiogramic activity on the selected isolates, followed by its ethanolic extract with zones of inhibition ranging from 0-24 mm and 0-16 mm respectively. The aqueous extract of M. fragrans was found to be effective against E. coli, P. aeruginosa and S. epidermidis only at 100 mg/mL. The MIC was also higher in oil extract of M. fragrans compared to its ethanolic and aqueous extracts. Conclusion, Significance and Impact of study: The oil and aqueous extract of M. fragrans showed antibiogramic properties against the bacterial isolates used at different concentrations. Thus, its oil can be used as an alternative to synthetic food preservative found to harbor toxic effects and could also serve as sources for development of new antibiotics.

  9. Phytochemical profiles and antimicrobial activity of aromatic Malaysian herb extracts against food-borne pathogenic and food spoilage microorganisms.

    Science.gov (United States)

    Aziman, Nurain; Abdullah, Noriham; Noor, Zainon Mohd; Kamarudin, Wan Saidatul Syida Wan; Zulkifli, Khairusy Syakirah

    2014-04-01

    Preliminary phytochemical and flavonoid compounds of aqueous and ethanolic extracts of 6 aromatic Malaysian herbs were screened and quantified using Reverse-Phase High Performance Liquid Chromatography (RP-HPLC). The herbal extracts were tested for their antimicrobial activity against 10 food-borne pathogenic and food spoilage microorganisms using disk diffusion assay. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)/minimum fungicidal concentration (MFC) of herbal extracts were determined. In the phytochemical screening process, both aqueous and ethanolic extracts of P. hydropiper exhibited presence of all 7 tested phytochemical compounds. Among all herbal extracts, the aqueous P. hydropiper and E. elatior extracts demonstrated the highest antibacterial activity against 7 tested Gram-positive and Gram-negative bacteria with diameter ranging from 7.0 to 18.5 mm and 6.5 to 19 mm, respectively. The MIC values for aqueous and ethanolic extracts ranged from 18.75 to 175 mg/mL and 0.391 to 200 mg/mL, respectively while the MBC/MFC values for aqueous and ethanolic extracts ranged from 25 to 200 mg/mL and 3.125 to 50 mg/mL, respectively. Major types of bioactive compounds in aqueous P. hydropiper and E. elatior extracts were identified using RP-HPLC instrument. Flavonoids found in these plants were epi-catechin, quercetin, and kaempferol. The ability of aqueous Persicaria hydropiper (L.) H. Gross and Etlingera elatior (Jack) R.M. Sm. extracts to inhibit the growth of bacteria is an indication of its broad spectrum antimicrobial potential. Hence these herbal extracts may be used as natural preservative to improve the safety and shelf-life of food and pharmaceutical products.

  10. Pan-European resistance monitoring programmes encompassing food-borne bacteria and target pathogens of food-producing and companion animals.

    Science.gov (United States)

    de Jong, A; Thomas, V; Klein, U; Marion, H; Moyaert, H; Simjee, S; Vallé, M

    2013-05-01

    Antimicrobial resistance is a concern both for animal and human health. Veterinary programmes monitoring resistance of animal and zoonotic pathogens are therefore essential. Various European countries have implemented national surveillance programmes, particularly for zoonotic and commensal bacteria, and the European Food Safety Authority (EFSA) is compiling the data. However, harmonisation is identified as a weakness and an essential need in order to compare data across countries. Comparisons of resistance monitoring data among national programmes are hampered by differences between programmes, such as sampling and testing methodology, and different epidemiological cut-off values or clinical breakpoints. Moreover, only very few valid data are available regarding target pathogens both of farm and companion animals. The European Animal Health Study Centre (CEESA) attempts to fill these gaps. The resistance monitoring programmes of CEESA have been a collaboration of veterinary pharmaceutical companies for over a decade and include two different projects: the European Antimicrobial Susceptibility Surveillance in Animals (EASSA) programme, which collects food-borne bacteria at slaughter from healthy animals, and the pathogen programmes that collect first-intention target pathogens from acutely diseased animals. The latter comprises three subprogrammes: VetPath; MycoPath; and ComPath. All CEESA projects include uniform sample collection and bacterial identification to species level in various European Union (EU) member states. A central laboratory conducts quantitative susceptibility testing to antimicrobial agents either important in human medicine or commonly used in veterinary medicine. This 'methodology harmonisation' allows easy comparisons among EU member states and makes the CEESA programmes invaluable to address food safety and antibiotic efficacy.

  11. Antimicrobial activity of Piper nigrum L. and Cassia didymobotyra L. leaf extract on selected food borne pathogens

    Directory of Open Access Journals (Sweden)

    Mohd. Sayeed Akthar

    2014-09-01

    Full Text Available Objective: To investigate the antimicrobial activity of leaf extract of Piper nigrum (P. nigrum and Cassia didymobotyra (C. didymobotyra (aqueous, methanol, ethanol and petroleum ether against the food borne pathogenic bacteria [Staphylococcus aureus (S. aureus, Escherichia coli (E. coli, Salmonella typhimurium and Pseudomonas aeruginosa] and fungi [Aspergillus spp. and Candida albicans (C. albicans] and also to investigate the presence of various phytochemicals in the leaf extracts of tested plants. Methods: The antimicrobial activity was determined by disc diffusion method. Minimum inhibitory concentration (MIC, minimum bactericidal and fungicidal concentration were determined by serial dilution method. Results: Methanol leaf extract of test plants exhibited greater antimicrobial activity against the selected bacterial and fungal strains. The MIC results showed that ethanol, methanol and petroleum ether leaf extract of P. nigrum inhibited the growth of S. aureus and E. coli at concentration of 12.5 mg/mL. While, ethanol and methanol leaf extracts of C. didymobotyra inhibited the growth of S. aureus at concentration of 6.25 mg/mL. The MIC values for ethanol, methanol and petroleum ether leaf extract of P. nigrum inhibited the growth of C. albicans at concentration of 25.0 mg/mL. While, it was reported that at concentration of 12.5 mg/mL methanol leaf extract of P. nigrum was against the Aspergillus spp. The MIC values of methanol leaf extract of C. didymobotyra inhibited the growth of C. albicans and Aspergillus spp. at concentration of 12.5 mg/mL and 6.25 mg/mL, respectively. The minimum bactericidal concentration of ethanol, methanol leaf extract of P. nigrum for E. coli and ethanol, methanol leaf extract of C. didymobotyra for S. aureus was recorded at concentration 12.5 mg/mL. The minimum fungicidal concentration of ethanol and methanol leaf extract of P. nigrum and C. didymobotyra on C. albicans was recorded at concentration of 25.0 mg

  12. Rapid Identification of Food-borne Pathogens by Top-Down Proteomics Using MALDI-TOF/TOF Mass Spectrometry

    Science.gov (United States)

    Rapid identification of bacterial microorganisms is particularly relevant to efforts to monitor the safety and security of domestically grown and imported foods. Mass spectrometry (MS) is increasingly utilized to identify and characterize bacterial microorganisms and in particular food-borne pathog...

  13. One Health and Food-Borne Disease: Salmonella Transmission between Humans, Animals, and Plants.

    Science.gov (United States)

    Silva, Claudia; Calva, Edmundo; Maloy, Stanley

    2014-02-01

    There are >2,600 recognized serovars of Salmonella enterica. Many of these Salmonella serovars have a broad host range and can infect a wide variety of animals, including mammals, birds, reptiles, amphibians, fish, and insects. In addition, Salmonella can grow in plants and can survive in protozoa, soil, and water. Hence, broad-host-range Salmonella can be transmitted via feces from wild animals, farm animals, and pets or by consumption of a wide variety of common foods: poultry, beef, pork, eggs, milk, fruit, vegetables, spices, and nuts. Broad-host-range Salmonella pathogens typically cause gastroenteritis in humans. Some Salmonella serovars have a more restricted host range that is associated with changes in the virulence plasmid pSV, accumulation of pseudogenes, and chromosome rearrangements. These changes in host-restricted Salmonella alter pathogen-host interactions such that host-restricted Salmonella organisms commonly cause systemic infections and are transmitted between host populations by asymptomatic carriers. The secondary consequences of efforts to eliminate host-restricted Salmonella serovars demonstrate that basic ecological principles govern the environmental niches occupied by these pathogens, making it impossible to thwart Salmonella infections without a clear understanding of the human, animal, and environmental reservoirs of these pathogens. Thus, transmission of S. enterica provides a compelling example of the One Health paradigm because reducing human infections will require the reduction of Salmonella in animals and limitation of transmission from the environment.

  14. Lactobacillus plantarum LB95 impairs the virulence potential of Gram-positive and Gram-negative food-borne pathogens in HT-29 and Vero cell cultures.

    Science.gov (United States)

    Dutra, Virna; Silva, Ana Carla; Cabrita, Paula; Peres, Cidália; Malcata, Xavier; Brito, Luisa

    2016-01-01

    Listeria monocytogenes, Salmonella enterica and verocytotoxigenic Escherichia coli (VTEC) are amongst the most important agents responsible for food outbreaks occurring worldwide. In this work, two Lactobacillus spp. strains (LABs), Lactobacillus plantarum (LB95) and Lactobacillus paraplantarum (LB13), previously isolated from spontaneously fermenting olive brines, and two reference probiotic strains, Lactobacillus casei Shirota and Lactobacillus rhamnosus GG, were investigated for their ability to attenuate the virulence of the aforementioned pathogens using animal cell culture assays. In competitive exclusion assays, the relative percentages of adhesion and invasion of S. enterica subsp. enterica serovar Enteritidis were significantly reduced when the human HT-29 cell line was previously exposed to LB95. The relative percentage of invasion by Listeria monocytogenes was significantly reduced when HT-29 cells were previously exposed to LB95. In the cytotoxicity assays, the cell-free supernatant of the co-culture (CFSC)of VTEC with LB95 accounted for the lowest value obtained amongst the co-cultures of VTEC with LABs, and was significantly lower than the value obtained with the co-culture of VTEC with the two probiotic reference strains. The cytotoxicity of CFSC of VTEC with both LB95 and LB13 exhibited values not significantly different from the cell-free supernatant of the nonpathogenic E. coli B strain. Our results suggested that LB95 may be able to attenuate the virulence of Gram-positive and Gram-negative food-borne pathogens; together with other reported features of these strains, our data reveal their possible use in probiotic foods due to their interesting potential in preventing enteric infections in humans.

  15. Future perspectives, applications and challenges of genomic epidemiology studies for food-borne pathogens: A case study of Enterohemorrhagic Escherichia coli (EHEC) of the O157:H7 serotype.

    Science.gov (United States)

    Eppinger, Mark; Cebula, Thomas A

    2015-01-01

    The shiga-toxin (Stx)-producing human pathogen Escherichia coli serotype O157:H7 is a highly pathogenic subgroup of Stx-producing E. coli (STEC) with food-borne etiology and bovine reservoir. Each year in the U. S., approximately 100,000 patients are infected with enterohemorrhagic E. coli (EHEC) of the O157:H7 serotype. This food-borne pathogen is a global public health threat responsible for widespread outbreaks of human disease. Since its initial discovery in 1982, O157:H7 has rapidly become the dominant EHEC serotype in North America. Hospitalization rates among patients as high as 50% have been reported for severe outbreaks of human disease. Symptoms of disease can rapidly deteriorate and progress to life-threatening complications such as Hemolytic Uremic Syndrome (HUS), the leading cause of kidney failure in children, or Hemorrhagic Colitis. In depth understanding of the genomic diversity that exists among currently circulating EHEC populations has broad applications for improved molecular-guided biosurveillance, outbreak preparedness, diagnostic risk assessment, and development of alternative toxin-suppressing therapeutics.

  16. Risk-based control of food-borne pathogens Listeria monocytogenes and Salmonella enterica in the Italian fermented sausages Cacciatore and Felino.

    Science.gov (United States)

    Mataragas, M; Bellio, A; Rovetto, F; Astegiano, S; Decastelli, L; Cocolin, L

    2015-05-01

    Fermentation is the most important killing step during production of fermented meats to eliminate food-borne pathogens. The objective was to evaluate whether the food-borne pathogens Listeria monocytogenes and Salmonella enterica may survive during the production of two Italian fermented sausages. Sausage batter was inoculated with five strains of L. monocytogenes or S. enterica (ca. 10(5)-10(6) cfu/g) and their kinetic behavior was monitored during production. Both pathogens survived relatively well (in Cacciatore L. monocytogenes and S. enterica inactivation was ca. 0.38±0.23 and 1.10±0.24 log cfu/g, respectively; in Felino was ca. 0.39±0.25 and 1.62±0.38 log cfu/g, respectively) due to the conditions prevailing during production (slow dehydration rate, small reduction of water activity and fermentation temperature mainly below 20 °C during the first 48 h of fermentation). Quantitative analysis of data originating from challenge tests provide critical information on which combinations of the process parameters would potentially lead to better control of the pathogens.

  17. Food-borne Zoonoses

    Science.gov (United States)

    Background: The awareness of food borne illness has shifted over the years as international agribusiness and transportation have steadily increased. At least 30 food borne agents have been identified, with one-third emerging in the last 3 decades. Despite an increased emphasis on control measures, t...

  18. Interaction Of ZnO Nanoparticles With Food Borne Pathogens Escherichia coli DH5α and Staphylococcus aureus 5021 & Their Bactericidal Efficacy

    Science.gov (United States)

    Kaur, Pawan; Thakur, Rajesh; Kumar, Sandeep; Dilbaghi, Neeraj

    2011-12-01

    Bactericidal activity of ZnO nanoparticles (np) against the food borne pathogens E. coli DH5α (Gram-ve) and & S. aureus 5021 (Gram+ve), and the mechanism of their interaction with target microbes was studied. Bactericidal activity of ZnO np was attributed to disruption of cell membrane causing cytoplasmic leakage, which was measured by quantifying the leakage of nucleic acids, proteins and K+ ions from the cells using UV-VIS Spectrophotometry and Atomic Absorption Spectrophotometry, respectively. Cell membrane disruption was observed through TEM. It is proposed that both the abrasiveness and the surface oxygen species of ZnO np are responsible for their biocidal properties.

  19. From ontology selection and semantic web to the integrated information system of food-borne diseases and food safety

    Science.gov (United States)

    Over the last three decades, the rapid explosion of information and resources on human food-borne diseases and food safety has provided the ability to rapidly determine and interpret the mechanisms of survival and pathogenesis of food-borne pathogens. However, several factors have hindered effective...

  20. Design and Elementary Evaluation of a Highly-Automated Fluorescence-Based Instrument System for On-Site Detection of Food-Borne Pathogens

    Directory of Open Access Journals (Sweden)

    Zhan Lu

    2017-02-01

    Full Text Available A simple, highly-automated instrument system used for on-site detection of foodborne pathogens based on fluorescence was designed, fabricated, and preliminarily tested in this paper. A corresponding method has been proved effective in our previous studies. This system utilizes a light-emitting diode (LED to excite fluorescent labels and a spectrometer to record the fluorescence signal from samples. A rotation stage for positioning and switching samples was innovatively designed for high-throughput detection, ten at most in one single run. We also developed software based on LabVIEW for data receiving, processing, and the control of the whole system. In the test of using a pure quantum dot (QD solution as a standard sample, detection results from this home-made system were highly-relevant with that from a well-commercialized product and even slightly better reproducibility was found. And in the test of three typical kinds of food-borne pathogens, fluorescence signals recorded by this system are highly proportional to the variation of the sample concentration, with a satisfied limit of detection (LOD (nearly 102–103 CFU·mL−1 in food samples. Additionally, this instrument system is low-cost and easy-to-use, showing a promising potential for on-site rapid detection of food-borne pathogens.

  1. Design and Elementary Evaluation of a Highly-Automated Fluorescence-Based Instrument System for On-Site Detection of Food-Borne Pathogens.

    Science.gov (United States)

    Lu, Zhan; Zhang, Jianyi; Xu, Lizhou; Li, Yanbin; Chen, Siyu; Ye, Zunzhong; Wang, Jianping

    2017-02-23

    A simple, highly-automated instrument system used for on-site detection of foodborne pathogens based on fluorescence was designed, fabricated, and preliminarily tested in this paper. A corresponding method has been proved effective in our previous studies. This system utilizes a light-emitting diode (LED) to excite fluorescent labels and a spectrometer to record the fluorescence signal from samples. A rotation stage for positioning and switching samples was innovatively designed for high-throughput detection, ten at most in one single run. We also developed software based on LabVIEW for data receiving, processing, and the control of the whole system. In the test of using a pure quantum dot (QD) solution as a standard sample, detection results from this home-made system were highly-relevant with that from a well-commercialized product and even slightly better reproducibility was found. And in the test of three typical kinds of food-borne pathogens, fluorescence signals recorded by this system are highly proportional to the variation of the sample concentration, with a satisfied limit of detection (LOD) (nearly 10²-10³ CFU·mL(-1) in food samples). Additionally, this instrument system is low-cost and easy-to-use, showing a promising potential for on-site rapid detection of food-borne pathogens.

  2. Rapid Detection Technology of Food-borne Pathogen%食源性致病菌快速检测技术研究进展

    Institute of Scientific and Technical Information of China (English)

    陈燕; 刘杰; 李玉兰; 刘芳生

    2013-01-01

    食品安全问题日益受到各国政府和人民的普遍关注.由食源性致病菌引起的食源性疾病是影响食品安全的最主要因素之一.对在食源性致病菌快速检测中应用前景广阔的多重PCR技术、生物芯片技术、酶联免疫法、免疫胶体金技术、蛋白芯片技术及生物传感器技术进行了概述,为食源性致病菌快速检测体系的建立提供依据.%Food safety problems are being paid more and more attention by governments and people from all over the world. Food-borne disease caused by food-bome pathogenic bacteria is one of the most important factors influencing food safety. So some rapid detection technologies such as multiplex PCR, microarray, ELISA, immune colloidal gold, protein microarray and biosensor were introduced, which aimed to provide some basis for the establishment of food-borne pathogenic bacteria rapid detection system.

  3. In vitro approaches to assess bioavailability and human gastrointestinal mobilization of food-borne polychlorinated biphenyls (PCBs).

    Science.gov (United States)

    Adenugba, Adeola A; McMartin, Dena W; Beck, Angus J

    2008-06-01

    This study reports on the potential for gastrointestinal (GI) mobilization and bioavailability of food-borne PCBs in humans. The development and validation of a GI simulator and operational protocols, developed in compliance with the requirements of German DIN 19738 risk assessment test procedure, are presented. Food, naturally contaminated with PCBs, was homogenized with simulated saliva fluid and shaken in the GI simulator with simulated gastric fluids (containing pepsin, mucine) for 2 h at 37 degrees C. Afterwards, the simulated intestinal fluids (containing pepsin, mucine, trypsin, pancreatin, bile) were added and the mixture shaken for a further 6 h prior to centrifugation and filtration using Buchner funnels to separate the undigested GI residues from GI fluids. PCBs were recovered from GI residues and fluids by Soxhlet and liquid-liquid extraction respectively, cleaned up using silica-SFE, and analyzed by gas chromatography mass spectrometry detection (GC-MSD). Detailed studies with fish indicate variations in mobilization and bioavailability of Sigma PCBs (28, 52, 101, 118, 153, 138 and 180). For example, the bioavailable fractions (fractions mobilized) in mackerel, salmon, crab and prawn were 0.77, 0.60, 0.54, and 0.72 respectively of the Sigma PCBs initially present in these food samples. The bioavailable fraction was dependent on the physicochemical characteristics of the PCBs. In mackerel bioavailable fractions for individual PCB congeners ranged from 0.47-0.82, from 0.30-0.70 in salmon, 0.44-0.64 in crab and in prawn from 0.47-0.77. Future studies will focus on understanding better, the variability in bioavailable fractions to be expected for different foodstuffs, in addition to tissue culture techniques using human gut cell lines to investigate a simultaneous mobilization and absorption of food-borne PCBs.

  4. Synergistic and antagonistic effect of lactic acid bacteria on tyramine production by food-borne pathogenic bacteria in tyrosine decarboxylase broth.

    Science.gov (United States)

    Kuley, Esmeray; Ozogul, Fatih

    2011-08-01

    The effect of lactic acid bacteria (LAB) strains on tyramine (TYR) and also other biogenic amines (BA) production by eight common food-borne pathogen (FBP) in tyrosine decarboxylase broth (TDB) was investigated by using a rapid HPLC method. Significant differences were observed among the FBP strains in ammonia (AMN) and BA production apart from tryptamine, histamine (HIS) and spermine formation (pfood-borne pathogenic bacteria, although the effect of some LAB strains on BA production was strain-dependent. Lactococcus spp. and Streptococcus spp. resulted in significantly higher TYR accumulation by Aeromonas hydrophila and Enterococcus faecalis in TDB. The presence of Lactococcus and/or Lactobacillus in TDB significantly increased HIS production by A. hydrophila, Escherichia coli, Ent. faecalis, Klebsiella pneumoniae and Pseudomonas aeruginosa, whereas HIS accumulation was significantly reduced by Staphylococcus aureus, S. paratyphi A and Listeria monocytogenes.

  5. Occurrence and characterization of food-borne pathogens isolated from fruit, vegetables and sprouts retailed in the Czech Republic.

    Science.gov (United States)

    Vojkovská, Hana; Myšková, Petra; Gelbíčová, Tereza; Skočková, Alena; Koláčková, Ivana; Karpíšková, Renáta

    2017-05-01

    Food of non-animal origin is a major component of the human diet and has been considered to pose a low risk from the point of view of bacteriological safety. However, an increase in the number of outbreaks of illness caused by such pathogens and linked to the consumption of fresh fruit and vegetables have been reported from around the world recently. Salmonella spp., STEC (Shiga toxin producing Escherichia coli) and Listeria monocytogenes are among the most frequently identified agents. Additionally, the transmission of antibiotic resistant strains including also the methicillin resistant S. aureus (MRSA) to humans via the food chain is one of the greatest public health problems being confronted today. Therefore, we focused on the bacterial safety of fruit, vegetables and sprouts on sale in the Czech Republic. One strain (0.3%) of Salmonella Enteritidis phage type PT8, one strain (0.3%) of MRSA and 17 strains (5.0%) of L. monocytogenes were isolated from a total of 339 collected samples. The most problematic commodities were frozen fruit and vegetables (packed and unpacked) and fresh-cut vegetables. Our findings indicate deficiencies in hygiene practices during harvesting, processing and distribution of these commodities. Although sprouts and berries are the most likely to be contaminated by human pathogens, only two samples were positive for the presence of L. monocytogenes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Automated analysis of food-borne pathogens using a novel microbial cell culture, sensing and classification system.

    Science.gov (United States)

    Xiang, Kun; Li, Yinglei; Ford, William; Land, Walker; Schaffer, J David; Congdon, Robert; Zhang, Jing; Sadik, Omowunmi

    2016-02-21

    We hereby report the design and implementation of an Autonomous Microbial Cell Culture and Classification (AMC(3)) system for rapid detection of food pathogens. Traditional food testing methods require multistep procedures and long incubation period, and are thus prone to human error. AMC(3) introduces a "one click approach" to the detection and classification of pathogenic bacteria. Once the cultured materials are prepared, all operations are automatic. AMC(3) is an integrated sensor array platform in a microbial fuel cell system composed of a multi-potentiostat, an automated data collection system (Python program, Yocto Maxi-coupler electromechanical relay module) and a powerful classification program. The classification scheme consists of Probabilistic Neural Network (PNN), Support Vector Machines (SVM) and General Regression Neural Network (GRNN) oracle-based system. Differential Pulse Voltammetry (DPV) is performed on standard samples or unknown samples. Then, using preset feature extractions and quality control, accepted data are analyzed by the intelligent classification system. In a typical use, thirty-two extracted features were analyzed to correctly classify the following pathogens: Escherichia coli ATCC#25922, Escherichia coli ATCC#11775, and Staphylococcus epidermidis ATCC#12228. 85.4% accuracy range was recorded for unknown samples, and within a shorter time period than the industry standard of 24 hours.

  7. In vitro assessment of the antimicrobial potentials of Lactobacillus helveticus strains isolated from traditional cheese in Sinkiang China against food-borne pathogens.

    Science.gov (United States)

    Bian, Xin; Evivie, Smith Etareri; Muhammad, Zafarullah; Luo, Guang-Wen; Liang, Hong-Zhang; Wang, Na-Na; Huo, Gui-Cheng

    2016-02-01

    Lactobacillus helveticus, an obligatory hetero-fermentative LAB, is Generally Recognized as Safe (GRAS) and is gaining popularity for application in dairy products. Lactic acid bacteria (LAB) play a remarkable role in inhibiting the growth of pathogenic bacteria in food products, without disturbing the sensory attributes of the food. In this study, the screening of the antimicrobial potential of Lactobacillus helveticus KLDS 1.8701 against four food-borne pathogens including Listeria monocytogenes ATCC 19115, Salmonella typhimurium ATCC 14028, Staphylococcus aureus ATCC 25923, and Escherichia coli O157:H7 ATCC 43889 in vitro was inspected using the Oxford cup method and mixed culture inhibition assays. The organic acid production and antimicrobial potential of the cell-free supernatants (CFS) have been evaluated via different treatments and analysis using high performance liquid chromatography (HPLC). The analysis results revealed that KLDS 1.8701 exhibited the highest antimicrobial potential compared to other antimicrobial strains. The antimicrobial activity of KLDS 1.8701 resulted from the organic acids in the culture and CFS. From the study, it was found that carbon sources, as well as organic acid production, accelerate the antimicrobial activity of KLDS 1.8701 and the fructooligosaccharides (FOS) were considered the best for improving the proliferation of KLDS 1.8701 and supporting its antimicrobial action. Results of the mixed culture inhibition assays showed that part of the antimicrobial activity resulted from the inhibitory action of the bacteria itself in culture, and this action required cellular contact between the food-borne pathogens and KLDS 1.8701. Conversely, the results of the antimicrobial spectrum assay revealed that some Lactobacilli remained unaffected by KLDS 1.8701. KLDS 1.8701 might also be favorable for use as a supplementary starter in fermented dairy productions. Furthermore, KLDS 1.8701 could survive well under GI tract conditions

  8. Food-borne pathogens Surveillance in Dalian city during 2011-2013%2011-2013年大连市食源性致病菌监测

    Institute of Scientific and Technical Information of China (English)

    肖冰; 徐丹; 陈玉凤; 吕秋月; 于蕾

    2016-01-01

    目的 了解大连市各类食品中食源性致病菌的污染情况,为有效预防和降低食源性疾病的发生提供科学依据.方法 2011-2013年采集大连市市售15类样品,共计758份,进行9种食源性致病菌的分离与鉴定.结果 758件样品中共检测出致病菌42株,总检出率为5.5%.检出食源性致病菌的食品包括:肉及肉制品(5.0%)、生食动物性水产品(9.4%)、即食非发酵豆制品(5.0%)、婴幼儿配方食品(2.9%)、鲜榨果蔬汁(10.0%)、米线凉皮盒饭冷面类(9.1%)、荤素烧烤类食品(3.3%)、冷冻饮品(4.0%)、焙烤食品(4.5%).其中,生食动物性水产品中的副溶血性弧菌检出率为8.9%;米线凉皮盒饭冷面类、即食非发酵豆制品和鲜榨果蔬汁中金黄色葡萄球菌的检出率分别为7.3%、5.0%、5.0%;鲜榨果蔬汁中沙门氏菌的检出率为5.0%,是大连市食源性致病菌风险来源的主要食品品种和项目.结论 大连市市售食品的现状不容乐观,存在不同程度的食源性致病菌污染,特别是部分生食品污染较为严重.应加强市售食品的监督管理,食品加工过程仍应采取烧熟煮透、防止交叉污染等针对性措施,减少由此引起的食源性疾病的发生.%Objective To investigate the situations and levels of main food-borne pathogens bacteria in food in Dalian city,and to provide scientific evidence for controlling and reducing food-borne diseases.Methods 9 kinds of food-borne pathogens were isolated and identified from 758 food samples of 15 types from 2011 to 2013.Results A total of 42 food-borne pathogens were isolated from 758 samples with relevance ratio of S.5%.The mainly food categories polluted by pathogenic bacteria are:meat and cooked meat products (5.0%),raw sea food (9.4%),non-fermented bean products (5.0%),infant formula food (2.9%),fresh fruit and vegetable juice (10.0%),rice noodle/cold noodle/boxed lunch/chilled noodle (9.1

  9. Emerging food-borne parasites.

    Science.gov (United States)

    Dorny, P; Praet, N; Deckers, N; Gabriel, S

    2009-08-07

    Parasitic food-borne diseases are generally underrecognised, however they are becoming more common. Globalization of the food supply, increased international travel, increase of the population of highly susceptible persons, change in culinary habits, but also improved diagnostic tools and communication are some factors associated with the increased diagnosis of food-borne parasitic diseases worldwide. This paper reviews the most important emerging food-borne parasites, with emphasis on transmission routes. In a first part, waterborne parasites transmitted by contaminated food such as Cyclospora cayetanensis, Cryptosporidium and Giardia are discussed. Also human fasciolosis, of which the importance has only been recognised in the last decades, with total numbers of reported cases increasing from less than 3000 to 17 million, is looked at. Furthermore, fasciolopsiosis, an intestinal trematode of humans and pigs belongs to the waterborne parasites as well. A few parasites that may be transmitted through faecal contamination of foods and that have received renewed attention, such as Toxoplasma gondii, or that are (re-)emerging, such as Trypanosoma cruzi and Echinococcus spp., are briefly reviewed. In a second part, meat-borne parasite infections are reviewed. Humans get infected by eating raw or undercooked meat infected with cyst stages of these parasites. Meat inspection is the principal method applied in the control of Taenia spp. and Trichinella spp. However, it is often not very sensitive, frequently not practised, and not done for T. gondii and Sarcocystis spp. Meat of reptiles, amphibians and fish can be infected with a variety of parasites, including trematodes (Opisthorchis spp., Clonorchis sinensis, minute intestinal flukes), cestodes (Diphyllobothrium spp., Spirometra), nematodes (Gnathostoma, spp., anisakine parasites), and pentastomids that can cause zoonotic infections in humans when consumed raw or not properly cooked. Another important zoonotic food-borne

  10. Beneficial Effects of Probiotic and Food Borne Yeasts on Human Health

    Directory of Open Access Journals (Sweden)

    Saloomeh Moslehi-Jenabian

    2010-04-01

    Full Text Available Besides being important in the fermentation of foods and beverages, yeasts have shown numerous beneficial effects on human health. Among these, probiotic effects are the most well known health effects including prevention and treatment of intestinal diseases and immunomodulatory effects. Other beneficial functions of yeasts are improvement of bioavailability of minerals through the hydrolysis of phytate, folate biofortification and detoxification of mycotoxins due to surface binding to the yeast cell wall.

  11. Beneficial effects of probiotic and food borne yeasts on human health

    DEFF Research Database (Denmark)

    Moslehi Jenabian, Saloomeh; Pedersen, Line Lindegaard; Jespersen, Lene

    2010-01-01

    Besides being important in the fermentation of foods and beverages, yeasts have shown numerous beneficial effects on human health. Among these, propiotic effects are the most well known health effects including prevention and treatment of intestinal diseases and immunomodulatory effects. Other be...... beneficial functions of yeasts are improvement of bioavailability of minerals through the hydrolysis of phytate, folate biofortification and detoxification of mycotoxins due to surface binding to the yeast cell wall....

  12. Evidence That the Enterotoxin Gene Can Be Episomal in Clostridium perfringens Isolates Associated with Non-Food-Borne Human Gastrointestinal Diseases

    OpenAIRE

    1998-01-01

    Clostridium perfringens enterotoxin (CPE) is responsible for the diarrheal and cramping symptoms of human C. perfringens type A food poisoning. CPE-producing C. perfringens isolates have also recently been associated with several non-food-borne human gastrointestinal (GI) illnesses, including antibiotic-associated diarrhea and sporadic diarrhea. The current study has used restriction fragment length polymorphism (RFLP) and pulsed-field gel electrophoresis (PFGE) analyses to compare the genoty...

  13. 太原市食品安全风险监测结果分析%Analysis of supervision results of food-borne pathogens in Taiyuan

    Institute of Scientific and Technical Information of China (English)

    王波; 高瑞红; 张晓华; 高丽; 王骥涛

    2016-01-01

    Objective To investigate the monitoring results of food safety risks of the past six years and the food-borne-disease pathogenic bacteria contamination in food from Taiyuan markets,so as to provide scientific basis for the formulation of food safety policy.Methods Food samples,which were regularly selected from 10 districts of Taiyuan,were delivered to laboratory in the shortest time according to the original storing temperature,and detected according to the programs and methods of the national standards.Results A total of 1 923 samples in 25 kinds were collected,with an overall detection rate of 9.62%;9 kinds of food-borne pathogenic bacteria were detected and isolated,and the detection rates of Pseudomonas aeruginosa and Bacillus cereus were higher,respectively as 20.83%,20.49%;the instant rice,milk and dairy product(adult),raw meat,breakfast street food were contaminated seriously;the detection rate of unpacked food was higher than the packaged food.Conclusion Food in Taiyuan is heavily contaminated by food-borne pathogens..The relevant departments should take measures and enhance the supervision to market food,so as to ensure the food safety for citizen.%目的 分析山西省太原市6年食品安全风险监测结果,了解市售食品中食源性致病菌的污染情况,为食品安全管理政策提供科学依据.方法 对太原市10个区(县)食品流通和餐饮服务环节随机抽取样品,按样品原有储存温度要求在最短时间内送达实验室,按相关的食品安全国家标准中规定的程序和方法进行检测.结果 共采集25类1 923份样品,总检出率为9.62%;共对9种食源性致病菌进行检测分析,其中铜绿假单胞菌和蜡样芽胞杆菌的检出率比较高,分别为20.83%、20.49%;盒饭、乳与乳制品(成人)、生肉、流动早餐的污染比较严重;散装食品的检出率高于包装食品.结论 太原市市售食品中食源性致病菌污染较为严重,相关部门应采取措施,

  14. [Food-borne botulism].

    Science.gov (United States)

    Nakamura, Yuko; Sawada, Mikio; Ikeguchi, Kunihiko; Nakano, Imaharu

    2012-08-01

    Botulism is a neuroparalytic disease caused by neurotoxins produced by Clostridium botulinum, and classically presents as palsies of cranial nerves and acute descending flaccid paralysis. Food-borne botulism is the most common form of botulism, and caused by preformed neurotoxins produced by Clostridium botulinum. Electrophysiological studies play an important role in the early diagnosis. Confirmation of the diagnosis is based on the detection of botulinum toxins in the patient's serum or stool. In Japan, decades ago, botulism type E occurred, though only sporadically, almost every year, but in recent years, has dramatically decreased in frequency. Botulism is a curable disease when treated early and adequately. Differential diagnosis of cranial nerves and limb muscle palsies with rapid exacerbation should include food-borne botulism.

  15. Food-borne zoonotic pathogens and antimicrobial resistance of indicator bacteria in urban wild boars in Barcelona, Spain.

    Science.gov (United States)

    Navarro-Gonzalez, Nora; Casas-Díaz, Encarna; Porrero, Concepción M; Mateos, Ana; Domínguez, Lucas; Lavín, Santiago; Serrano, Emmanuel

    2013-12-27

    Wildlife is increasingly abundant in urban environments, but little is known about the zoonotic pathogens carried by these populations. Urban wild boars are of particular concern because this species is well-known as a pathogen reservoir, and thus, we studied selected zoonotic pathogens in urban wild boars in Barcelona, Spain (n=41). Salmonella enterica was found in 5.00% (95% CI 0.61-16.91) and Campylobacter coli in 4.88% (95% CI 0.6-16.53) of the animals. E. coli O157:H7 and C. jejuni were not found. Other thermophilic Campylobacter were moderately prevalent (19.51%, 95% CI 8.82-34.87). Additionally, we screened for antimicrobial resistance in indicator bacteria: resistance was most frequent in Enterococcus faecium (95% of the isolates were resistant to at least one antimicrobial agent), followed by Enterococcus faecalis (50%) and Escherichia coli (10%). For the first time resistance to linezolid in bacteria carried by wildlife is reported. These findings pose a concern for public health, and thus, further research is needed on wildlife in urban environments.

  16. 2012年大连市食源性致病菌监测分析%Monitoring of food-borne pathogens in Dalian City in 2012

    Institute of Scientific and Technical Information of China (English)

    王凡; 郑晓南; 张磊

    2013-01-01

    目的监测大连市主要食源性致病菌污染状况,为预防食源性疾病和食物中毒提供科学依据。方法在本市的大型超市、农贸市场、餐饮店和专卖店等随机采集11类食品,依据《食品卫生微生物学检验》GB/T4789-2003/2008,对采集样品分别进行副溶血性弧菌、蜡样芽胞杆菌、金黄色葡萄球菌、沙门氏菌、单核细胞增生李斯特氏菌、志贺氏菌分离、生化及血清学鉴定。结果共监测肉制品、生食动物性水产品、海产品、焙烤食品等11类样品740份,检出食源性致病菌36株,总检出率4.86%(36/740)。其中副溶血性弧菌9株,检出率7.5%(9/120);蜡样芽胞杆菌2株,检出率3.3%(2/60);金黄色葡萄球菌18株,检出率2.9%(18/620);沙门氏菌5株,检出率0.73%(5/682);单核细胞增生李斯特氏菌2株,检出率0.59%(2/340);志贺氏菌未检出。结论大连市食品存在食源性致病菌污染较严重,其中海产品、生食动物性水产品、熟制米面制品、婴幼儿食品、冷面、凉拌菜是主要受污染食品;应加强食源性致病菌的监测,防止食源性疾病和食物中毒发生。%Aim To monitor main food-borne pathogens ,and provide the scientific basis for the prevention of foodborne diseases and food poisoning in Dalian City. Methods The pathogens of Vibrio parahaemolyticu, Bacillus cereus , Staphylococcus aureus,Salmonella,Listeria monocytogenes,and Shigella were isolated,the biochemical and serotypewere tested according to"Methods of microbiology tests for food's hygiene " (GB/T4789-2003[1]/2008[2])Results There 680 food samples in 11 categories including meat, raw food of animal aquatic products, seafood, baked goods ,et al.were tested, 36 bacteria strains of food-borne pathogens were isolated and the total positive rate was 4.86%(36/740).There were 9 Vibrio parahaemolyticu strains with the detection rate of 7.5%(9/120); 2 Bacillus cereus strains with the

  17. TrpA1 Regulates Defecation of Food-Borne Pathogens under the Control of the Duox Pathway.

    Directory of Open Access Journals (Sweden)

    Eun Jo Du

    2016-01-01

    Full Text Available Pathogen expulsion from the gut is an important defense strategy against infection, but little is known about how interaction between the intestinal microbiome and host immunity modulates defecation. In Drosophila melanogaster, dual oxidase (Duox kills pathogenic microbes by generating the microbicidal reactive oxygen species (ROS, hypochlorous acid (HOCl in response to bacterially excreted uracil. The physiological function of enzymatically generated HOCl in the gut is, however, unknown aside from its anti-microbial activity. Drosophila TRPA1 is an evolutionarily conserved receptor for reactive chemicals like HOCl, but a role for this molecule in mediating responses to gut microbial content has not been described. Here we identify a molecular mechanism through which bacteria-produced uracil facilitates pathogen-clearing defecation. Ingestion of uracil increases defecation frequency, requiring the Duox pathway and TrpA1. The TrpA1(A transcript spliced with exon10b (TrpA1(A10b that is present in a subset of midgut enteroendocrine cells (EECs is critical for uracil-dependent defecation. TRPA1(A10b heterologously expressed in Xenopus oocytes is an excellent HOCl receptor characterized with elevated sensitivity and fast activation kinetics of macroscopic HOCl-evoked currents compared to those of the alternative TRPA1(A10a isoform. Consistent with TrpA1's role in defecation, uracil-excreting Erwinia carotovora showed higher persistence in TrpA1-deficient guts. Taken together, our results propose that the uracil/Duox pathway promotes bacteria expulsion from the gut through the HOCl-sensitive receptor, TRPA1(A10b, thereby minimizing the chances that bacteria adapt to survive host defense systems.

  18. Low dietary iron intake restrains the intestinal inflammatory response and pathology of enteric infection by food-borne bacterial pathogens.

    Science.gov (United States)

    Kortman, Guus A M; Mulder, Michelle L M; Richters, Thijs J W; Shanmugam, Nanda K N; Trebicka, Estela; Boekhorst, Jos; Timmerman, Harro M; Roelofs, Rian; Wiegerinck, Erwin T; Laarakkers, Coby M; Swinkels, Dorine W; Bolhuis, Albert; Cherayil, Bobby J; Tjalsma, Harold

    2015-09-01

    Orally administrated iron is suspected to increase susceptibility to enteric infections among children in infection endemic regions. Here we investigated the effect of dietary iron on the pathology and local immune responses in intestinal infection models. Mice were held on iron-deficient, normal iron, or high iron diets and after 2 weeks they were orally challenged with the pathogen Citrobacter rodentium. Microbiome analysis by pyrosequencing revealed profound iron- and infection-induced shifts in microbiota composition. Fecal levels of the innate defensive molecules and markers of inflammation lipocalin-2 and calprotectin were not influenced by dietary iron intervention alone, but were markedly lower in mice on the iron-deficient diet after infection. Next, mice on the iron-deficient diet tended to gain more weight and to have a lower grade of colon pathology. Furthermore, survival of the nematode Caenorhabditis elegans infected with Salmonella enterica serovar Typhimurium was prolonged after iron deprivation. Together, these data show that iron limitation restricts disease pathology upon bacterial infection. However, our data also showed decreased intestinal inflammatory responses of mice fed on high iron diets. Thus additionally, our study indicates that the effects of iron on processes at the intestinal host-pathogen interface may highly depend on host iron status, immune status, and gut microbiota composition.

  19. Monitoring of Food - borne Pathogens in Yongzhou City in 2011%2011年永州市食源性致病菌监测

    Institute of Scientific and Technical Information of China (English)

    陈蓉; 唐旭辉

    2012-01-01

    Objective To investigate the status of food - bome pathogens contamination in market - sold foods in Yongzhou, Hunan Province. Methods The food -bome pathogens, including Salmonella spp. , Listeria monocytogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus, Shigella spp., Escherichia coli O157 :H7 and Enterobacter sakaza-kii were detected according to the Handbook of National Surveillance Network on Food - borne Diseases in 2011. Results Totally 20 strains of pathogens were identified in the 198 samples collected from cooked meat products, egg products, quick frozen cooked rice products, ready - to - use non- fermented soybean products, cakes or biscuit, cold and dressed vegetable, fresh fruits or vegetables juice, rice noodles (fast foods, rice noodles and cold noodles) and infant foods, with a total detection rate of 10.10%. Among 9 kinds of foods samples detected, the pathogen detection rate of quick frozen cooked rice products was the highest (27.27%). The pathogen detection rates in cooked meat products, rice noodles, cakes, cold and dressed vegetable, fresh fruits or vegetables juice and infant foods were 18.18%, 18.18%, 9.09%, 9.09%, 4.55% and4.55%, respectively. Conclusions The market - sold foods in Yongzhou Gty, especially the quick frozen cooked rice products, cooked meat products and rice noodles, are contaminated to by pathogens some extend. The food supervision and law enforcement departments should pay more attention to monitoring these food products so as to decrease and prevent the food - borne diseases effectively.%目的 了解湖南省永州市食品中食源性致病菌污染状况.方法 依据国家食源性疾病监测网2011年度工作手册,进行沙门菌、单增李斯特菌、金黄色葡萄球菌、蜡样芽孢杆菌、志贺菌、大肠埃希菌O157、阪崎肠杆菌的检测.结果 检测熟肉制品、蛋制品、速冻熟制米面制品、即食非发酵性豆制品、糕点及饼干、凉拌菜、鲜榨果蔬

  20. 2011年大连市食源性致病菌监测分析%Monitoring of food-borne pathogens in Dalian City in 2011

    Institute of Scientific and Technical Information of China (English)

    郑晓南; 李瑞; 王凡

    2013-01-01

    Objective To monitor main food-borne pathogens ,and provide the scientific basis for the prevention of foodborne diseases and food poisoning in Dalian City. Methods In the city supermarkets, farmers' markets, restaurants and specialty stores were randomly collected 10 food samples were collected seven pathogen monitoring indicators based on "Microbiological examination of food hygiene GB/T4789-2003/2008 including: Salmonella, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli O157, Shigella, Vibrio parahaemolyticus, Enterobacter sakazakii isolation, biochemical and serological identification. Results monitored cooked meat products, raw food of animal aquatic products, salad, freshly squeezed fruit and vegetable juices for a total of 204 samples, the detection of foodborne pathogens 13, the detection rate of 6.37% (13/204). Conclusion Dalian Food and more polluting presence of foodborne pathogens, including freshly squeezed fruit and vegetable juices, raw food animal aquatic products, rice noodle Cold, cooked meat products, soy products are mainly contaminated food; should strengthen foodborne pathogens monitoring, to prevent food-borne diseases and food poisoning.%目的监测大连市主要食源性致病菌污染状况,为预防食源性疾病和食物中毒提供科学依据。方法在本市的大型超市、农贸市场、餐饮店和专卖店等随机采集10类食品,依据《食品卫生微生物学检验》GB/T4789-2003/2008,对采集样品进行7项致病菌监测指标包括:沙门氏菌、金黄色葡萄球菌、单核细胞增生李斯特氏菌、大肠杆菌O157、志贺氏菌、副溶血性弧菌、阪崎肠杆菌分离、生化及血清学鉴定。结果共监测熟肉制品、生食动物性水产品、凉拌菜、鲜榨果蔬汁等共计204份样品,检出食源性致病菌13株,总检出率6.37%(13/204)。结论大连市食品存在食源性致病菌污染较严重,其中鲜榨果蔬汁、生食动物性水产品

  1. 2010年达州市食源性致病菌监测%Monitoring of Food-borne Pathogenic Bacteria in Dazhou City in 2010

    Institute of Scientific and Technical Information of China (English)

    王卓; 李德华; 周汉洪; 李红; 常虹; 薛镧

    2012-01-01

    Objective To understand the contamination situation of food - borne pathogen in food market of Dazhou in 2010, so as to identify high - risk foods and provide the basis for food - borne diseases prevention and control in Dazhou City. Methods On - sale raw meat, raw poultry, cooked meat, deep frozen cooked rice products, ready to use non - fermentation bean products, fresh frozen aquatic products, uncooked aquatic products, uncooked vegetables, baby formula rice (grain, bean) powder, icecream, Chinese salad, salad, fresh fruit juice, preserved eggs and raw duck eggs were sampled with stratified multi - stage method, and the following bacteria were detected; Salmonella spp, Listeria monocytogens, Vibrio parahemolyticus, Staphylococ-cus aureus, Escherichia coli 0 Enterobacter sakazakii, Campylobacter jejuni and Vibrio vulnificus, according to national standard and relevant methods. Results Among a total of 256 samples in 15 classes, 29 strains of food - borne pathogenic bacteria were detected; Vibrio parahemolyticus, 9; Listeria monocytogens , 8; Staphy-lococcus aureus, 6; Salmonella spp, 4; Enterobacter sakazakii 1; Escherichia coli O157: H 7, 1, with a total positive rate of 11. 33%. Higher positive rates were found in fresh frozen aquatic products (42. 86% ) , ice cream (33. 33% ), uncooked aquatic products (20. 00% ) , cooked meat (19. 04% ) , raw meat and ready to use non - fermentation bean products (13. 33% ). Conclusion In Dazhou, major kinds of consumed foods were contaminated by food -borne pathogens. Fresh frozen aquatic products, ice cream, uncooked aquatic products and cooked meat were mainly contaminated respectively by Vibrio parahemolyticus, Staphylococcus aureus and Listeria monocytogens.%目的 了解达州市2010年市售食品的食源性致病菌污染状况,为控制和降低食源性疾病提供依据.方法 多级分层抽样市售生畜肉、生禽肉、熟肉制品、速冻熟制米面制品、即食非发酵性豆制品、鲜冻水产品、

  2. Prevalence of swine Hepatitis E virus in Europe and its role as emerging zoonosis and food-borne pathogen

    Directory of Open Access Journals (Sweden)

    Eleonora Sarno

    2013-04-01

    Full Text Available Hepatitis E virus (HEV is responsible for enterically-transmitted acute hepatitis, a selflimiting disease in humans occurring via fecal-oral route. Hepatitis E virus is classified in the Hepeviridae family and consists of at least four genotypes. Genotypes 1 and 2 are restricted to humans and associated with epidemics in developing countries, whereas genotypes 3 and 4 are responsible for sporadic cases worldwide. Among all hepatitis (A, B, C and D, HEV is the only one with animal reservoirs. Swine HEV is widespread among pig population and several studies show phylogenetic relatedness between human and swine strains supporting the zoonotic hypothesis. Sporadic cases have also been linked to consumption of raw or undercooked food from infected animals. Therefore, swine strains of HEV pose not only a zoonotic risk but also food safety concerns. To assess this hypothesis, further investigations are required. The aim of the present article is to present a short overview on the HEV knowledge with respect to pig and human prevalence and its role as emerging zoonosis.

  3. Multiplex detection of nine food-borne pathogens by mPCR and capillary electrophoresis after using a universal pre-enrichment medium

    Science.gov (United States)

    Villamizar-Rodríguez, Germán; Fernández, Javier; Marín, Laura; Muñiz, Juan; González, Isabel; Lombó, Felipe

    2015-01-01

    Routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. This is necessary in order to ensure that small amounts of pathogenic strains are going to be detected. In this work, a universal pre-enrichment medium has been developed for the simultaneous growth of Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Cronobacter sakazakii, Escherichia coli, Enterobacteriaceae family (38 species, 27 genera), Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. (two species, 13 strains). Growth confirmation for all these species was achieved in all cases, with excellent enrichments. This was confirmed by plating on the corresponding selective agar media for each bacterium. This GVUM universal pre-enrichment medium could be useful in food microbiological analyses, where different pathogenic bacteria must be detected after a pre-enrichment step. Following, a mPCR reaction for detection of all these pathogens was developed, after designing a set of nine oligonucleotide pairs from specific genetic targets on gDNA from each of these bacteria, covering all available strains already sequenced in GenBank for each pathogen type. The detection limits have been 1 Genome Equivalent (GE), with the exception of the Fam. Enterobacteriaceae (5 GEs). We obtained amplification for all targets (from 70 to 251 bp, depending on the bacteria type), showing the capability of this method to detect the most important industrial and sanitary food-borne pathogens from a universal pre-enrichment medium. This method includes an initial pre-enrichment step (18 h), followed by a mPCR (2 h) and a capillary electrophoresis (30 min); avoiding the tedious and long lasting growing on solid media required in traditional analysis (1–4 days, depending on the specific pathogen and verification procedure). An external testing of this method was conducted in order to compare classical and mPCR methods. This evaluation was

  4. Multiplex detection of nine food-borne pathogens by mPCR and capillary electrophoresis after using a universal pre-enrichment medium

    Directory of Open Access Journals (Sweden)

    Germán eVillamizar-Rodríguez

    2015-11-01

    Full Text Available Routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. This is necessary in order to assure that small amounts of pathogenic strains are going to be detected. In this work, a universal pre-enrichment medium has been developed for simultaneous growth of Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Cronobacter sakazakii, Escherichia coli, Enterobacteriaceae family (thirty eight species, twenty seven genera, Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. (two species, thirteen strains. Growth confirmation for all these species was achieved in all cases, with excellent enrichments. This was confirmed by plating on the corresponding selective agar media for each bacterium. This GVUM universal pre-enrichment medium could be useful in food microbiological analyses, where different pathogenic bacteria must be detected after a pre-enrichment step. Following, a mPCR reaction for detection of all these pathogens was developed, after designing a set of nine oligonucleotide pairs from specific genetic targets on gDNA from each of these bacteria, covering all available strains already sequenced in GenBank for them. The detection limits have been 1 Genome Equivalent, with the exception of Fam. Enterobacteriaceae (5 GEs. We obtained amplification for all targets (from 70 to 251 bp, depending on the bacteria type, showing the capability of this method to detect the most important industrial and sanitary food-borne pathogens from a universal pre-enrichment medium. This method includes an initial pre-enrichment step (18 h, followed by a mPCR (2 h and a capillary electrophoresis (30 min; avoiding the tedious and long lasting growing on solid media required in traditional analysis (1 to 4 days, depending on the specific pathogen and verification procedure. An external testing of this method was conducted in order to compare classical and mPCR methods. This

  5. Occurrence of emerging food-borne pathogenic Arcobacter spp. isolated from pre-cut (ready-to-eat) vegetables.

    Science.gov (United States)

    Mottola, Anna; Bonerba, Elisabetta; Bozzo, Giancarlo; Marchetti, Patrizia; Celano, Gaetano Vitale; Colao, Valeriana; Terio, Valentina; Tantillo, Giuseppina; Figueras, Maria José; Di Pinto, Angela

    2016-11-01

    Given that changes in consumer food behaviours have led to an increase in the demand for pre-cut ready-to-eat (RTE) vegetables, and that few data are currently available on the occurrence of Arcobacter spp. in such foods, the aim of the present study was to assess the occurrence of Arcobacter spp. that carry virulence-associated genes on pre-cut RTE vegetables, using cultural and molecular methods. Arcobacter was detected using biomolecular identification methods in 44/160 (27.5%) of the samples, of which 40/44 (90.9%) isolates corresponded to A. butzleri and 4/44 (9.1%) to A. cryaerophilus. Studying the incidence of 9 virulence-associated genes revealed the widespread distribution of these genes among the Arcobacter isolates tested. The results obtained in our research provided plenty of information on the health risks associated with the direct consumption of raw vegetables, and highlight the need to implement further studies at each level of the production chain, in order to obtain further information to help protect human health.

  6. 南充市散装即食食品中食源性致病菌监测%Monitoring of Food-borne Pathogens in Bulk Ready-to-use Food in Nanchong

    Institute of Scientific and Technical Information of China (English)

    赵朝珍; 王娟; 徐买成

    2012-01-01

    目的 了解南充市即食食品中食源性致病菌污染状况,为预防和控制食源性疾病提供科学依据.方法 随机抽取具代表性的4类食品,依据国标方法,对584件样品进行沙门菌、金黄色葡萄球菌、单核细胞增生李斯特菌、大肠杆菌O157:H7、志贺菌5种食源性致病菌分离鉴定.结果 584件食品中检出50株致病菌,总检出率为8.56% (50/584).5种食源性致病菌中,金黄色葡萄球菌检出率最高(6.68%),其次为单核细胞增生李斯特菌(1.03%)和沙门菌(0.86%),未检出大肠埃希菌O157和志贺菌.结论 南充市散装即食食品中存在食源性致病菌污染,应加强食品卫生监督管理,防止食源性疾病发生.%Objective To investigate the pollution situation of food - borne pathogens in instant food in Nanchong so as to provide scientific basis for the prevention and control of food - borne diseases. Methods Four types of food from local area were selected randomly as representatives. According to the national standard method 5 kinds of food - borne pathogens were isolated and identified in 584 samples, including Salmonella, Staphylococ-cus aureus, Listeria monocytogenes, Escherichia coli (E. coli) 0157: H7and Shigella. Results Fifty pathogens was detected in 584 samples, making a total detection rate of 8. 56% ( 50/584). Among the 5 types of food - borne pathogens, Staphylococcus aureus's detection rate was the highest (6. 68% ) , followed by mononu-clear cell hyperplasia Listeria (1. 03% ) and salmonella bacteria (0. 86% ). Coli 0157 and shigella was not detected. Conclusions Food - borne padiogens pollution do widely exists with high risk of spread and infection. The supervision and management of food hygiene should be strengthened in order to prevent food - borne diseases.

  7. The influence of the cell free solution of lactic acid bacteria on tyramine production by food borne-pathogens in tyrosine decarboxylase broth.

    Science.gov (United States)

    Toy, Nurten; Özogul, Fatih; Özogul, Yesim

    2015-04-15

    The function of cell-free solutions (CFSs) of lactic acid bacteria (LAB) on tyramine and other biogenic amine production by different food borne-pathogens (FBPs) was investigated in tyrosine decarboxylase broth (TDB) using HPLC. Cell free solutions were prepared from four LAB strains. Two different concentrations which were 50% (5 ml CFS+5 ml medium/1:1) and 25% (2.5 ml CFS+7.5 ml medium/1:3) CFS and the control without CFS were prepared. Both concentration of CFS of Streptococcus thermophilus and 50% CFS of Pediococcus acidophilus inhibited tyramine production up to 98% by Salmonella paratyphi A. Tyramine production by Escherichia coli was also inhibited by 50% CFS of Lactococcus lactis subsp. lactis and 25% CFS of Leuconostoc lactis. subsp. cremoris. The inhibitor effect of 50% CFS of P. acidophilus was the highest on tyramine production (55%) by Listeria monocytogenes, following Lc. lactis subsp. lactis and Leuconostoc mesenteroides subsp. cremoris (20%) whilst 25% CFS of Leu. mes. subsp. cremoris and Lc. lactis subsp. lactis showed stimulator effects (160%). The stimulation effects of 50% CFS of S. thermophilus and Lc. lactis subsp. lactis were more than 70% by Staphylococcus aureus comparing to the control. CFS of LAB strains showed statistically inhibitor effect since lactic acid inhibited microbial growth, decreased pH quickly and reduced the formation of AMN and BAs. Consequently, in order to avoid the formation of high concentrations of biogenic amines in fermented food by bacteria, it is advisable to use CFS for food and food products.

  8. Contribution of the stereospecific methionine sulphoxide reductases MsrA and MsrB to oxidative and nitrosative stress resistance in the food-borne pathogen Campylobacter jejuni.

    Science.gov (United States)

    Atack, John M; Kelly, David J

    2008-08-01

    The microaerophilic food-borne pathogen Campylobacter jejuni is exposed to highly variable oxygen concentrations during its life cycle and employs a variety of protection mechanisms to resist oxidative stress. However, not all of the enzymes that mediate such protection have yet been identified. Two genes in strain NCTC 11168, Cj0637c and Cj1112c, are predicted to encode unrelated methionine sulphoxide reductases, which may repair oxidized methionine residues in proteins and thus contribute to oxidative stress defence. Cj0637 and Cj1112 were overexpressed, purified and shown by a coupled thioredoxin-thioredoxin reductase-NADPH assay to catalyse the stereospecific reduction of the S and R diastereoisomers, respectively, of the model compound methyl p-tolyl sulphoxide. Cj0637 is thus identified as MsrA and Cj1112 as MsrB. The contribution of these enzymes to oxidative and nitrosative stress resistance in C. jejuni was assessed by phenotypic analysis of a set of isogenic msrA, msrB and msrA/B insertion mutants. As RT-PCR data suggested a polar effect on Cj1111c in the msrB mutant, an msrB/msrB(+) merodiploid complementation strain was also constructed. The msrA/B strain was severely growth inhibited under standard microaerobic conditions, whereas the msrA and msrB strains grew normally. Agar plate disc diffusion assays showed that all mutants displayed increased sensitivity to hydrogen peroxide, organic peroxide, superoxide, and nitrosative and disulphide stress, but quantitative cell viability assays showed that the msrA/B double mutant was markedly more sensitive to both oxidative and nitrosative stress. All of the stress-sensitivity phenotypes observed for the msrB mutant were restored to wild-type in the msrB/msrB(+) merodiploid. It is concluded that MsrA and MsrB make a significant contribution to the protection of C. jejuni against oxidative and nitrosative stress.

  9. 食品病原微生物快速检测技术研究进展%Research advances for fast detection of food borne pathogenic bacteria

    Institute of Scientific and Technical Information of China (English)

    杨春光; 王宏伟; 彭心婷; 苏明明; 徐静; 李莉; 孙兴权; 曹际娟

    2015-01-01

    随着现在食品工业的快速发展,食品安全越来越受到各国的重视。影响食品安全的因素很多,其中食品中的病原微生物是影响食品安全的主要因素之一。为了对食品安全进行有效、快速的监测,控制食品加工中的病原微生物,研究和建立食品病原快速检测方法对于食品质量控制和监管及人们健康也就越来越重要。食源性致病菌的传统检测方法繁琐复杂、周期较长,因而快速、简便、特异的检测方法成为研究的热点。快速检测方法的应用范围非常广泛,并且比传统的检测方法更加敏感。本文主要从分子生物学技术、免疫技术、代谢技术、生物传感器技术等方面介绍了目前国内外用于食品微生物检测的先进技术,并对这些在当前较为先进的主流的快速检测技术进行总结分析,为今后进一步研究和开发新检测技术提供一些参考。%Now with the rapid development of food industry, food safety is concerned all over the world. Many factors affect the food safety, among which pathogenic microbe is one of the most primary factor. In order to effectively and efficiently monitor the food safety, it is more and more important for food quality control and supervision to control the pathogenic microorganism in food processing, and establish the method for rapid detection of food pathogen. Traditional methods for detection of food borne pathogens are quite complex, and cost much time, so more researches focus on the quick, convenient and differential methods. The scope of application of rapid detection method is very extensive, and more sensitive than the traditional detection method. This article introduced several advanced fast detection technology of food pathogenic bacteria, including molecular biology technology, immunity technology, metabolism technology and biosensor technology, and the rapid detection technology of those more advanced analysis and

  10. MALDI-TOF-MS技术鉴定食源性致病菌的影响因素%Influential factors in identifying food-borne pathogens by MALDI-TOF-MS

    Institute of Scientific and Technical Information of China (English)

    吕佳; 卢行安; 刘淑艳; 柳媛; 闫磊; 初雷

    2011-01-01

    Using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) to identify food-borne pathogens is still at a developing stage in China. The mass spectra obtained by MALDI-TOF-MS in identifying food-borne pathogens provides biological information of the strain and is the key to the successful identification. This article summarizes the main factors that influence the results of identification, including the selection of matrix, culture conditions of food-borne pathogens, method of sample preparation, and renewal and supplement of database, with a view to reducing the interference from these factors and giving full play to the advantages of MALDI-TOF-MS technique.%基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术鉴定食源性致病菌在我国尚处于发展阶段.MALDI-TOF-MS鉴定食源性致病菌形成的质谱图反映菌株的生物学信息,也是获得鉴定结果的关键.本文综述了影响MALDI-TOF-MS鉴定的主要因素:基质的选择、食源性致病菌的培养条件、样品的处理方式、数据库资源的更新与补充,以达到减小这些因素的干扰,最大程度地发挥MALDI-TOF-MS技术优势的目的.作为一种便捷的食源性致病菌鉴定技术,MALDI-TOF-MS必将在该领域发挥巨大作用.

  11. Analysis of results in monitoring food-borne pathogens in Shenyang during the first part of 2011%沈阳市2011年上半年食源性致病菌监测结果分析

    Institute of Scientific and Technical Information of China (English)

    连英姿; 安静; 侯元; 刘建敏; 王侠

    2011-01-01

    目的:了解沈阳市售食品中食源性致病菌污染状况及分布.方法:在全国食源性疾病监测网控制体系下,2011年上半年采集沈阳市6个监测点内的十大类市售食品共计102份,对其进行沙门菌、大肠杆菌O157:H7、单核细胞增生李斯特菌、金黄色葡萄球菌、副溶血性弧菌5种食源性致病菌的监测分析.结果:102份食品样品中,分离出目的菌6株,其中肠炎沙门菌1株,金黄色葡萄球菌3株,单核细胞增生李斯特菌2株,总检出率5.88%.结论:通过对沈阳市售食品中食源性致病菌主动监测,掌握食源性致病菌的污染状况,及时发现食品安全隐患,有效预防食源性疾病的发生.%Objective:To understand status and distribution of food - borne pathogen contamination in market - sold food in Shenyang. Methods; According to the instruction of national surveillance network on food - borne disease, 102 food samples were collected from marketplace in 6 monitoring sites during the first part of 2011, pathogens were detected and identified for the presence of Salmonella spp. ,Escherichia coli 0157 ;H7, Listeria Monocytogenes, Vibrio parahaemolyticus and Staphylococcus aureus. Results; Totally 6 pathogenic strains (5. 88% ) were identified in the 102 foods samples, including 1 salmonella isolate, 3 Staph-ylococcus aureus, 2 Listeria Monocytogenes. Conclution: Through active monitoring of food - borne pathogens, we can grasp the contamination status and adopt measures for potential safety hazard timely to prevent the food - borne disease effectively.

  12. 食源性致病菌傅里叶变换红外光谱快速鉴别方法%Screening and Identification Method of Food-borne Pathogens using FTIR

    Institute of Scientific and Technical Information of China (English)

    王磊; 唐颖; 徐凯; 张之韵; 赵冰; 郭鲁申; 赵渝

    2011-01-01

    利用傅里叶变换红外光谱(FTIR)分析食源性致病菌脂多糖粗提物,建立一种微生物快速筛选、鉴别的方法.分析5种(8株)典型革兰氏阴性食源性致病菌脂多糖的红外光谱特征区段的差异,采用分级聚类分析方法对结果进行比较,并用菌株16srDNA的亲缘性分析进行比对验证.结果表明,革兰氏阴性食源性致病菌脂多糖的光谱特征区间分别为1750~1500 cm-1、1500~1360 cm-1、1160~920 cm-1和890~750 cm-1.聚类结果显示,基于脂多糖的红外光谱分析方法,不仅可以区分不同种属的微生物、致病与非致病性食源性致病菌,而且还能将同种不同分离株的食源性致病菌归类聚合.FTIR结合多元分析方法可用于食源性致病菌的快速筛选研究.%A rapid identification methods of microbial species was established by the Fourier transform infrared (FTIR) spectra of erode lipopolysaccharides extracted from five different kinds of gram-negative food-borne bacteria.According to the difference in each strain's characteristic range, their relationship were compared and identified by clustering method. In addition, the method had been proved to be reliable by the analysis of clustering and phylogenetic tree based on 16srDNA. The result showed that the characteristic ranges of gram-negative food-borne bacterial were 1 750~1 500 cm-1, 1 500~1 360 cm-1, 1 160~920 cm-1 and 890~750 cm-1. Different species of food-borne pathogens can be identified significantly based on the method of FTIR to crude lipopolysaecharides. With these protocols,virulent and avirulent food-borne pathogens can be identified. The result of clustering also demonstrated that this method can classify the strains which were separated from a same species. FTIR combined with a multidimensional approach show high potential as a rapid, accurate and easy-to-use method for the identification of food-borne pathogens. It will bo an important practical tool in the

  13. Phylogenetic and molecular analysis of food-borne shiga toxin-producing Escherichia coli.

    Science.gov (United States)

    Hauser, Elisabeth; Mellmann, Alexander; Semmler, Torsten; Stoeber, Helen; Wieler, Lothar H; Karch, Helge; Kuebler, Nikole; Fruth, Angelika; Harmsen, Dag; Weniger, Thomas; Tietze, Erhard; Schmidt, Herbert

    2013-04-01

    Seventy-five food-associated Shiga toxin-producing Escherichia coli (STEC) strains were analyzed by molecular and phylogenetic methods to describe their pathogenic potential. The presence of the locus of proteolysis activity (LPA), the chromosomal pathogenicity island (PAI) PAI ICL3, and the autotransporter-encoding gene sabA was examined by PCR. Furthermore, the occupation of the chromosomal integration sites of the locus of enterocyte effacement (LEE), selC, pheU, and pheV, as well as the Stx phage integration sites yehV, yecE, wrbA, z2577, and ssrA, was analyzed. Moreover, the antibiotic resistance phenotypes of all STEC strains were determined. Multilocus sequence typing (MLST) was performed, and sequence types (STs) and sequence type complexes (STCs) were compared with those of 42 hemolytic-uremic syndrome (HUS)-associated enterohemorrhagic E. coli (HUSEC) strains. Besides 59 STs and 4 STCs, three larger clusters were defined in this strain collection. Clusters A and C consist mostly of highly pathogenic eae-positive HUSEC strains and some related food-borne STEC strains. A member of a new O26 HUS-associated clone and the 2011 outbreak strain E. coli O104:H4 were found in cluster A. Cluster B comprises only eae-negative food-borne STEC strains as well as mainly eae-negative HUSEC strains. Although food-borne strains of cluster B were not clearly associated with disease, serotypes of important pathogens, such as O91:H21 and O113:H21, were in this cluster and closely related to the food-borne strains. Clonal analysis demonstrated eight closely related genetic groups of food-borne STEC and HUSEC strains that shared the same ST and were similar in their virulence gene composition. These groups should be considered with respect to their potential for human infection.

  14. Surveillance results of food-borne pathogens in Dalian City in 2011%2011年大连市食源性致病菌监测结果

    Institute of Scientific and Technical Information of China (English)

    肖冰; 侯君; 徐丹

    2013-01-01

    目的 了解大连市食品中食源性致病菌的污染状况,为食源性疾病的监测和预警提供科学依据.方法 按照《全国食源性致病菌监测工作手册》的要求,对大连市区农贸市场、大型超市、宾馆酒店及个体摊贩销售点的10类食品进行沙门菌、单核细胞增生李斯特菌、大肠埃希菌O157:H7、志贺菌、金黄色葡萄球菌、副溶血性弧菌和蜡样芽孢杆菌7种食源性致病菌进行监测分析.结果 10类共296份样品检出致病菌19株,总检出率为6.4%.其中沙门菌2株,金黄色葡萄球菌5株,副溶血性弧菌12株.结论 大连市市售食品不同程度受到多种食源性致病菌的污染,水产品、鲜榨果蔬汁、即食非发酵性豆制品和熟肉制品为主要受污染食品,应加强市售食品监督管理,减少由此引起食源性疾病的发生.%[Objective] To know the contamination status of food-borne pathogens in food in Dalian City, provide scientific basis for surveillance and early-warning of food-borne diseases. [Methods] According to the requirements of the Food-borne Pathogen Monitoring Manual, 7 food-borne pathogens, including Salmonella, listeria monocytogenes, Escherichia coli 0157:H7, Shigella, Staphylococcus aureus, Vibrio parahaemolyticus and Bacillus cereus, in the samples of 10 kinds of food which collected from farmers'markets, shopping mall, hotels and retail outlets were monitored and analyzed. [Results] A total of 19 food-bome pathogens were isolated from 296 samples with the total detection of 6. 4% . There were 2 strains of Salmonella, 5 strains of Staphylococcus aureus and 12 strains of Vibrio parahaemolyticus. [Conclusion]The food in Dalian markets are contaminated by food-bome pathogens at different degrees, and the main contaminated food include aquatic food, fruit and vegetable juice, instant- non-fermented bean products and cooked meat products. It is necessary to strengthen the supervision and management to reduce the

  15. 江阴市2009-2011年食源性致病菌监测研究%Monitoring on food - borne pathogenic bacteria in Jiangyin city during 2009 to 2011

    Institute of Scientific and Technical Information of China (English)

    缪国忠; 高海英; 蒋建章; 王均华

    2012-01-01

    目的 了解江阴市市售食品中食源性致病菌的污染状况,寻找本市引起食源性疾病的重点食品,对可能发生的食源性疾病进行预警.方法 采集8大类食品,按国标及相关方法对7种食源性致病菌进行分离、生化及血清学鉴定.结果 604份样品中检出食源性致病菌90份,平均检出率为14.90%,8类食品中,以散装熟肉制品的污染最严重,其次为凉拌菜、生禽肉类;致泻性弧菌检出率为11.09%,以副溶血性弧菌为主,占致泻性弧菌的44.64%;金黄色葡萄球菌检出率为1.71%;单增李斯特菌检出率为7.32%;变形杆菌检出率为6.07%;未检出EHECO157∶H7、沙门氏菌、志贺氏菌.结论 江阴市市售食品中食源性致病菌污染较为严重,散装熟肉制品、凉拌菜、生禽肉类是主要污染食品,应加强细菌性食源性疾病相关危险因子的研究分析,做好食品安全预警工作.%Objective To leam the contamination status of food - borne pathogenic bacteria of food in Jiangyin, look for the key food which caused food origin diseases and early warning the contingent diseases. Method Collecting 8 kinds of food and 7 kinds of food - borne pathogenic bacteria were isolated from them and biochemistry and serological identification them according to national standards and correlation methods. Results Total of 90 food - borne pathogenic bacteria were detected from 604 samples and average detection rate was 14. 90%. Among the 8 kinds of food, no packaging cooked products contamination were the most serious, the second were the cold food and raw meat. The detection rate of diarrhea vibrio was 11. 09% , vibrio parahaemo-lyticus was the primarily, it accounted for 44. 64% , staphylococcus aureus detection rate was 1. 71% , listeria was 7. 32% , bacillus proteus was 6. 07% , no EHECO157: H7, salmonella and shigella. Conclusions The contamination status of food - borne pathogenic bacteria was serious, especially no

  16. Food-borne origins of Escherichia coli causing extraintestinal infections.

    Science.gov (United States)

    Manges, Amee R; Johnson, James R

    2012-09-01

    Most human extraintestinal Escherichia coli infections, including those involving antimicrobial resistant strains, are caused by the members of a limited number of distinctive E. coli lineages, termed extraintestinal pathogenic E. coli (ExPEC), that have a special ability to cause disease at extraintestinal sites when they exit their usual reservoir in the host's intestinal tract. Multiple lines of evidence suggest that many of the ExPEC strains encountered in humans with urinary tract infection, sepsis, and other extraintestinal infections, especially the most extensively antimicrobial-resistant strains, may have a food animal source, and may be transmitted to humans via the food supply. This review summarizes the evidence that food-borne organisms are a significant cause of extraintestinal E. coli infections in humans.

  17. 2009-2011年深圳市食源性致病菌监测结果%Analysis on monitoring results of food-borne pathogens in Shenzhen from 2009-2011

    Institute of Scientific and Technical Information of China (English)

    罗贤如; 王冰; 黄薇; 张锦周; 张燕; 王舟; 潘柳波; 范兴; 张志航

    2013-01-01

    [Objective]To understand the contamination status of pathogens in food in Shenzhen, provide scientific basis for effective prevention and control of food-borne disease. [Methods] 9 kind of food samples were selected to detect Salmonella, listeria monocytogenes, Vibrio parahaemolyticus, Escherichia coli 0157 : H7, Staphylococcus aureus, Shigella, Campylobacter jejuni, Vibrio vulnificus and Enterobacter sakazakii. [ Results] A total of 4 873 food samples were tested for food-bome pathogens, 331 pathogens were isolated with the total detection rate of 6. 79%. The livestock meat had the most serious contamination by Vibrio parahaemolyticus with the detection rate of 20.40%. [ Conclusion] There exists different degree of food-borne pathogens contamination in the main food in Shenzhen. If is necessary to carry out effective control measures, strengthen food safety supervision and management, to reduce the incidence of food-borne disease.%目的 了解深圳市食品中致病菌污染状况,为有效防治食源性疾病提供科学依据.方法 2009-2011年抽取深圳市9类食品样品,进行沙门菌、单核细胞增生李斯特菌、副溶血性弧菌、大肠杆菌0157:H7、金黄色葡萄球菌、志贺菌、空肠弯曲菌、创伤弧菌、阪崎肠杆菌检测.结果 9类食品共4 873件样品检出6种致病菌331株,总检出率6.79%.其中,畜肉类副溶血弧菌污染最严重,检出率高达20.40%.结论 深圳市主要食品存在不同程度的食源性致病菌污染,应采取有效的控制措施,加强食品卫生监督管理,减少食源性疾病的发生.

  18. 食源性致病菌焦磷酸通用引物测序方法的建立%The Study of Pyrosequencing Method by the Universal Primers for Food-borne Pathogenic Bacteria

    Institute of Scientific and Technical Information of China (English)

    赵新; 王永; 兰青阔; 陈锐; 朱珠; 余景会; 李欧静; 郭永泽

    2013-01-01

      建立一种利用焦磷酸测序技术检测和鉴定沙门氏菌(Salmonellla)、单核细胞增生李斯特菌(Listeria monocytogenes)、金黄色葡萄球菌(Staphylococcus aureus)和志贺氏菌(Shigella)的方法。通过对4种菌16SrRNA的保守序列可变区的同源性分析,设计出一套适合焦磷酸测序的扩增引物和测序引物,通过可变区位点差异,利用一套通用引物同时鉴别4种食源性致病菌,测序结果与数据库比对判断细菌种属。结果表明:建立的检测方法可在4 h内完成对4种菌的鉴定,测序鉴定结果与国标的传统生化方法完全一致,焦磷酸测序技术可用于食源性致病菌的检测和鉴定。%The method of pyrosequencing technology for identification of Salmonellla spp, Listeria monocytogenes, Staphylococcus aureus and Shigella cereus was established. According to nucleotide homology analysis of 16S rRNA of 4 food-borne pathogenic bacteria,we designed one set of primer,including one universal PCR primers and one pyrosequencing sequencing primer. The 4 pathogenic bacteria were distinguished on the basis of pyrosequencing signal peaks. The result showed that the identification of four-kinds of food-borne pathogenic bacteria was completed in 4 h, the results of identification of bacteria were consistent with the result of GB/T method. The pyrosequencing method can use for detection and identification of food-borne pathogenic bacteria.

  19. Lactase persistence and augmented salivary alpha-amylase gene copy numbers might have been selected by the combined toxic effects of gluten and (food born) pathogens.

    Science.gov (United States)

    Pruimboom, Leo; Fox, Tom; Muskiet, Frits A J

    2014-03-01

    Various positively selected adaptations to new nutrients have been identified. Lactase persistence is among the best known, conferring the ability for drinking milk at post weaning age. An augmented number of amylase gene (AMY1) copies, giving rise to higher salivary amylase activity, has been implicated in the consumption of starch-rich foods. Higher AMY1 copy numbers have been demonstrated in populations with recent histories of starchy-rich diets. It is however questionable whether the resulting polymorphisms have exerted positive selection only by providing easily available sources of macro and micronutrients. Humans have explored new environments more than any other animal. Novel environments challenge the host, but especially its immune system with new climatic conditions, food and especially pathogens. With the advent of the agricultural revolution and the concurrent domestication of cattle came new pathogens. We contend that specific new food ingredients (e.g., gluten) and novel pathogens drove selection for lactase persistence and higher AMY gene copy numbers. Both adaptations provide ample glucose for activating the sodium glucose-dependent co-transporter 1 (SGLT1), which is the principal glucose, sodium and water transporter in the gastro-intestinal tract. Their rapid uptake confers protection against potentially lethal dehydration, hyponatremia and ultimately multiple organ failure. Oral rehydration therapy aims at SGLT1 activity and is the current treatment of choice for chronic diarrhoea and vomiting. We hypothesize that lifelong lactase activity and rapid starch digestion should be looked at as the evolutionary covalent of oral rehydration therapy.

  20. Staphylococcus aureus and Staphylococcal Food-Borne Disease: An Ongoing Challenge in Public Health

    Directory of Open Access Journals (Sweden)

    Jhalka Kadariya

    2014-01-01

    Full Text Available Staphylococcal food-borne disease (SFD is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail industry account for the majority of SFD outbreaks. However, several studies have documented prevalence of S. aureus in many food products including raw retail meat indicating that consumers are at potential risk of S. aureus colonization and subsequent infection. Presence of pathogens in food products imposes potential hazard for consumers and causes grave economic loss and loss in human productivity via food-borne disease. Symptoms of SFD include nausea, vomiting, and abdominal cramps with or without diarrhea. Preventive measures include safe food handling and processing practice, maintaining cold chain, adequate cleaning and disinfection of equipment, prevention of cross-contamination in home and kitchen, and prevention of contamination from farm to fork. This paper provides a brief overview of SFD, contributing factors, risk that it imposes to the consumers, current research gaps, and preventive measures.

  1. Staphylococcus aureus and staphylococcal food-borne disease: an ongoing challenge in public health.

    Science.gov (United States)

    Kadariya, Jhalka; Smith, Tara C; Thapaliya, Dipendra

    2014-01-01

    Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail industry account for the majority of SFD outbreaks. However, several studies have documented prevalence of S. aureus in many food products including raw retail meat indicating that consumers are at potential risk of S. aureus colonization and subsequent infection. Presence of pathogens in food products imposes potential hazard for consumers and causes grave economic loss and loss in human productivity via food-borne disease. Symptoms of SFD include nausea, vomiting, and abdominal cramps with or without diarrhea. Preventive measures include safe food handling and processing practice, maintaining cold chain, adequate cleaning and disinfection of equipment, prevention of cross-contamination in home and kitchen, and prevention of contamination from farm to fork. This paper provides a brief overview of SFD, contributing factors, risk that it imposes to the consumers, current research gaps, and preventive measures.

  2. Monitoring of food-borne pathogens in Maoming City from 2008 to 2009%2008~2009年茂名市食源性致病菌监测分析

    Institute of Scientific and Technical Information of China (English)

    罗雪梅; 廖国东; 黄水飞; 许铭清; 陈家图; 陈伟冰

    2011-01-01

    Aim To monitor main food-borne pathogens ,and provide the scientific basis for the prevention of foodborne diseases and food poisoning in Maoming City. Methods The pathogens of Salmonella,Listeria monocytogenes,Staphylococcus aureus , Escherichia coli O157:H7 and Vibrio parahaemolyticus were isolated,the biochemical and serotype were tested according to"Methods of microbiology tests for food's hygiene"(GB/r4789-2003[1]/2008[2]) . Results There 273 food samples in 6 categories including uncooked meat of livestock and poultry,cooked meat products ,salad vegetables,beans products ,aquatic products and raw milk were tested,33 bacteria strains of food-borne pathogens were isolated and the total positive rate was 12.09%(33/273). There were 22 Salmonella strains with the detection rate of 8.70% (22/253);3 Listeria monocytogenes strains with the detection rate of 1.19% (3 / 253); 5 Vibrio parahaemolyticus strains with the detection rate of 8.93%(5/56); 5 Staphylococcus aureus strains with the detection rate of 2.65%(3/113); E. coli O157:H7 was not detected. Conclusion Foods were contaminated by food-borne pathogens in MaoMing City,uncooked meat of livestock and poultry,raw milk ,aquatic products and cooked meat products were the main contaminated foods. The work of minotring of foodborne pathogens be lstrengthened to prevent the occurrence of food-borne diseases and food poisoning.%目的 监测茂名市主要食源性致病菌污染状况,为预防食源性疾病和食物中毒提供科学依据.方法 在本市的大型超市、农贸市场、餐饮店和养殖场等随机采集六类食品.依据GB/T4789-2003/2008,对采集样品分别进行沙门菌、单核细胞增生性李斯特菌、金黄色葡萄球菌、大肠杆菌O157:H7和副溶血性弧菌分离、生化及血清学鉴定.结果 共监测生禽畜肉、熟肉制品、凉拌菜、豆类制品、水产品及生奶等6类样品273份,检出食源性致病菌33株,总检出率12.09%(33/273).

  3. 贵阳市市售鸡肉中五种食源性致病菌污染状况调查研究%Investigation of Five Kinds of Food - borne Pathogen in Retail Chicken Meat in Guiyang City

    Institute of Scientific and Technical Information of China (English)

    任慧婧; 谭艾娟; 吕世明; 金志强; 方英; 尹泽东

    2012-01-01

    The pollutions of five kinds of food - borne pathogenic bacteria in retail chicken in Guiyang city were, investigated. The results show that the total detection rates of food - borne pathogenic bacteria in 50 retail chicken samples was 48% , among which, the detection rates of Campylobacter jejuni, salmonella, staphylococcus aureus, Shigella in 50 retail chicken samples were 24. 0% , 22. 0% , 6. 0% , 2. 0% respectively, and no Listeria monocytogene was determined. The detection rates of frozen chicken and fresh chicken were 55% and 20% , respectively. The detection rate of food - borne pathogenic bacteria in 34 frozen chicken samples in open warket was 58. 8% , among which, the detection rates of Campylobacter jejuni, salmonella, staphylococcus aureus, Shigella were 32. 3% , 17. 6% , 5. 9% 2. 9% , 0 respectively. The detection rate of food - borne pathogenic bacteria in six frozen chicken samples that were sold in supermarket was 33. 3% , a-mong which, the detection rates of Campylobacter jejuni, salmonella, staphylococcus aureus, Shigella in six samples were 0, 16. 7% , 16. 7% , 0, 0, respectively.%对贵阳市市售鸡肉中5种食源性致病菌的污染情况进行调查,结果表明:50份样品中食源性致病菌总检出率为48%,其中空肠弯曲菌、沙门氏菌、金黄色葡萄球菌、志贺氏菌和单核细胞增生李斯特菌的检出率分别为24.0%、22.0%、6.0%、2.0%、0,40份冻鸡肉样品的检出率为55%,10份鲜鸡肉样品的检出率为20%.对农贸市场市售冻鸡肉样品进行抽查,34份样品中5种致病菌的检出率为58.8%,其中空肠弯曲菌、沙门氏菌、金黄色葡萄球菌、志贺氏菌和单核细胞增生李斯特菌的检出率分别为32.3%、17.6%、5.9%、2.9%、0;对6份超市冻鸡肉样品进行检测,食源性致病菌的检出率为33.3%,其中空肠弯曲菌、沙门氏菌、金黄色葡萄球菌、志贺氏菌和单核细胞增生李斯特菌的裣出率分别为0、16

  4. Food-borne pathogens in meat and aquatic products in Jiangsu province,2008-2009%江苏省2008-2009年肉类和水产品食源性致病菌监测

    Institute of Scientific and Technical Information of China (English)

    王燕梅; 乔昕; 符晓梅; 沈赟; 袁宝君; 戴月

    2011-01-01

    Objective To know the contamination situation of food-borne pathogens in meat and aquatic products in Jiangsu province. Methods According to GB/T 4789 examination method,990 meat and aquatic products from 13 cities in Jiangsu province were detected for Salmonella, Listeria monocytogens , Vibrio parahaemolyticus , Campylobacter jejuni , and Escherichia coli O157. Results Among the samples, 161 bacteria strains were isolated with an overall positive rate of 16. 26%. The detection rate of the pathogens for raw meat,cooked meat,frozen aquatic food,and raw aquatic products were 26. 32% ,7.37%, 17.78%, and 14. 78%, respectively. Food products from Taizhou city had the highest positive rate of food-born pathogens,followed by Nanjing and Yangzhou city. Positive rate of foods from wholesale markets was 22. 92% and that of from supermarkets and stores was 15.37% ,and 6. 76% from restaurants. Conclusion There existed food-borne pathogen contamination in meat and aquatic products in Jiangsu province. The intake of cooked meat and raw aquatic food without heating is more likey to cause food-borne diseases.%目的 了解江苏省肉类和水产品中食源性致病菌的污染状况.方法 按照GB/T 4789方法对采自江苏省13个市的肉类和水产品共计990份进行沙门氏菌、单增李斯特菌、大肠埃希菌O157、弯曲菌和副溶血性弧菌检测.结果 990份肉类和水产品中共检出致病菌161株,总检出率为16.26%,生肉类、熟肉类食品、鲜冻水产品、生食水产品检出率分别为26.32%、7.37%、17.78%、14.78%;不同地区样品中,泰州市食源性致病菌总检出率最高,为37.97%,其次为南京市和扬州市;采自农贸批发市场、超市和商店、饭店和食堂的样品中食源性致病菌检出率分别为22.99%、15.37%、6.76%.结论 江苏省肉类和水产品中食源性致病菌污染比较严重,熟肉制品和生食水产品直接入口,可能导致较高的食源性疾病风险.

  5. Negligible Colon Cancer Risk from Food-Borne Acrylamide Exposure in Male F344 Rats and Nude (nu/nu) Mice-Bearing Human Colon Tumor Xenografts

    Science.gov (United States)

    Raju, Jayadev; Roberts, Jennifer; Sondagar, Chandni; Kapal, Kamla; Aziz, Syed A.; Caldwell, Don; Mehta, Rekha

    2013-01-01

    Acrylamide, a possible human carcinogen, is formed in certain carbohydrate-rich foods processed at high temperature. We evaluated if dietary acrylamide, at doses (0.5, 1.0 or 2.0 mg/kg diet) reflecting upper levels found in human foods, modulated colon tumorigenesis in two rodent models. Male F344 rats were randomized to receive diets without (control) or with acrylamide. 2-weeks later, rats in each group received two weekly subcutaneous injections of either azoxymethane (AOM) or saline, and were killed 20 weeks post-injections; colons were assessed for tumors. Male athymic nude (nu/nu) mice bearing HT-29 human colon adenocarcinoma cells-derived tumor xenografts received diets without (control) or with acrylamide; tumor growth was monitored and mice were killed 4 weeks later. In the F344 rat study, no tumors were found in the colons of the saline-injected rats. However, the colon tumor incidence was 54.2% and 66.7% in the control and the 2 mg/kg acrylamide-treated AOM-injected groups, respectively. While tumor multiplicity was similar across all diet groups, tumor size and burden were higher in the 2 mg/kg acrylamide group compared to the AOM control. These results suggest that acrylamide by itself is not a “complete carcinogen”, but acts as a “co-carcinogen” by exacerbating the effects of AOM. The nude mouse study indicated no differences in the growth of human colon tumor xenografts between acrylamide-treated and control mice, suggesting that acrylamide does not aid in the progression of established tumors. Hence, food-borne acrylamide at levels comparable to those found in human foods is neither an independent carcinogen nor a tumor promoter in the colon. However, our results characterize a potential hazard of acrylamide as a colon co-carcinogen in association with known and possibly other environmental tumor initiators/promoters. PMID:24040114

  6. 南京市2007年-2010年食源性致病菌监测分析%Surveillance on food-borne pathogens in food in Nanjing city from 2007 to 2010

    Institute of Scientific and Technical Information of China (English)

    叶艳华; 江晓; 王炜; 丁洁

    2011-01-01

    目的:了解南京市食品中食源性致病菌的污染状况,为食源性疾病的监测和预警提供科学依据.方法:2007年-2010年采集南京市售食品共计459份,对沙门菌、单核细胞增生李斯特菌、大肠埃希菌0157:H7、金黄色葡萄球菌、空肠弯曲菌和副溶血性弧菌6种食源性致病菌进行监测分析.结果:459份食品样品中,检出致病菌61株,总检出率13.3%.2007年-2010年食源性致病菌检出率分别为25.3%、21.3%、7.9%和6.9%.生肉的污染情况最为严重,检出率为45.8 %,其次是生速食米面制品,检出率为24%,水产品、熟肉制品和凉拌菜的检出率分别为14.1%、13.3%和5.9%.结论:沙门菌和单核细胞增生李斯特菌对南京市食品的污染普遍存在.生肉、生速食米面制品和熟肉制品是可能导致食源性疾病的高危食品.%Objective:To investigate the situations and levels ol main food - borne pathogens bacteria in food in Nanjing city and to provide scientific basis for prevention and control of food - borne diseases. Methods; From 2007 to 2010, 459 retail food samples were collected and analyzed for the occurrence of Salmonella ,Listeria monocytogenes ,Escherichia coli 0157: H7 ,Staphy-lococcus aureus,Campylobacter and Vibrio parahaemolyticus. Results.- Among all samples, 61 pathogenic strains were isolated and the overall positive rate were 13. 3%. The positive rate of food - borne pathogens bacteria from 2007 to 2010 were 25. 3% , 21.3% ,7.9% and 6.9% respectively. The positive rate in raw meat, quick -frozen flour and rice products, aquatic products, cooked meat and Chinese cold dishes were 45. 8% , 24% , 14. 1% , 13. 3% and 5. 9% respectively. Conclusion; The results showed that Salmonella and Listeria monocytogenes widely existed in foods in Nanjing city. Raw meat, quick - frozen flour and rice products and cooked meats were the higher risk foods to cause food - borne diseases.

  7. 实时荧光定量PCR技术在食源性致病菌检测中的应用%Application of Real-time Fluorescent Quantitative PCR for the Detection of Food-borne Pathogenic Bacteria

    Institute of Scientific and Technical Information of China (English)

    吕艳芳; 马春颖; 励建荣

    2014-01-01

    近年来食源性疾病爆发数量呈上升趋势,食品安全问题已经成为危害人们生命和健康的严重问题,引起了全世界消费者对食品品质、安全和卫生的关注。实时荧光定量PCR技术是在定性PCR技术的基础上发展起来的核酸定量技术,灵敏性高、特异性强,实现了对DNA模板的定量检测,目前已广泛应用于食品检测领域。本文概述了实时荧光定量PCR技术的原理及其在食源性致病菌检测中的应用,并对其应用前景进行了探讨。%The outbreak of food-borne disease has shown a rising trend in recent years, and the problem of food safety seriously threats people’s life and health. Consumers around the world pay much attention to food quality, safety and health. Real-time fluorescent quantitative PCR technique is a nucleic acid quantitative technique, on the basis of the qualitative PCR technology, having high sensitivity, strong specificity, which has realized the quantita-tive detection of DNA template, and now has been widely used in the field of food detection. This paper summa-rized the principle of real-time fluorescent quantitative PCR technique and its application in the detection of food-borne pathogenic bacteria, and discussed the application prospect.

  8. Complete genome sequence of Lactobacillus plantarum LZ206, a potential probiotic strain with antimicrobial activity against food-borne pathogenic microorganisms.

    Science.gov (United States)

    Li, Ping; Gu, Qing; Zhou, Qingqing

    2016-11-20

    Lactobacilli strains have been considered as important candidates for manufacturing "natural food", due to their antimicrobial properties and generally regarded as safe (GRAS) status. Lactobacillus plantarum LZ206 is a potential probiotic strain isolated from raw cow milk, with antimicrobial activity against various pathogens, including Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes), Gram-negtive bacteria (Escherichia coli and Salmonella enterica), and fungus Candida albicans. To better understand molecular base for its antimicrobial activity, entire genome of LZ206 was sequenced. It was revealed that genome of LZ206 contained a circular 3,212,951-bp chromosome, two circular plasmids and one predicted linear plasmid. A plantaricin gene cluster, which is responsible for bacteriocins biosynthesis and could be associated with its broad-spectrum antimicrobial activity, was identified based on comparative genomic analysis. Whole genome sequencing of L. plantarum LZ206 might facilitate its applications to protect food products from pathogens' contamination in the dairy industry.

  9. 2009-2011年梧州市食品中食源性致病菌监测结果%Surveillance results of food-borne pathogens in food in Wuzhou City from 2009-2011

    Institute of Scientific and Technical Information of China (English)

    冼桂江; 彭美薇; 盘珍梅

    2012-01-01

    目的 了解梧州市食品中食源性致病菌污染状况,为食源性疾病监测和预防控制提供科学依据.方法 按照GB/T 4789 - 2010和2011年国家食源性疾病监测工作手册进行检测和鉴定.结果 2009年120份食品中副溶血性弧菌检出率为35.00%,沙门菌检出率为14.17%,金黄色葡萄球菌检出率为10.00%,单增李斯特菌和大肠杆菌0157∶H7未检出.2010年150份食品中副溶血性弧菌检出率为48.00%,沙门菌检出率为9.33%.金黄色葡萄球菌检出率为2.53%,单增李斯特菌检出率为2.41%,大肠杆菌0157∶H7和阪崎肠杆菌未检出.2011年175份食品中副溶血性弧菌检出率为17.39%,阪崎肠杆菌的检出率为5.26%,金黄色葡萄球菌的检出率为4.61%,单增李斯特菌的检出率为2.92%,沙门菌和大肠杆菌0157:H7未检出.结论 该市食品存在安全隐患,重点食物中致病菌检出率都很高,食品安全执法部门应采取有效监管措施,减少和避免食源性中毒的发生.%[ Objective] To know the pollution condition of food-borne pathogens in food in Wuzhou City, provide a scientific basis for prevention and monitoring of food-borne diseases. [ Methods ] The detection and identification was performed according to GB/T 4789-2010 and the National food-borne disease monitoring handbook. [Results] Among 120 food samples collected in 2009, the detection rate of Vibrio parahaemolyticus, Salmonella and Staphylococcus aureus was 35.00% , 14. 17% and 10.00% respectively. Iisteria monocytogenes and Escherichia coli O157: H7 were not found. Among 150 samples collected in 2010, the detection rate of Vibrio parahaemolyticus, Salmonella, Staphylococcus aureus and Iisteria monocytogenes respectively was 48.00% ,9. 33% , 2. 53% and 2.41%. Escherichia coli O157: H7 and Enterobacter sakazakii were not found. Among 175 samples collected in 2011, Vibrio parahaemolyticus, Enterobacter sakazakii, Staphylococcus aureus and Iisteria monocytogenes

  10. 2007~2008年荆州市食源性致病菌监测分析%Monitoring and analysis of food-borne pathogenic bacteria in the City of Jingzhou from 2007 to 2008

    Institute of Scientific and Technical Information of China (English)

    胡国才; 益琼; 石韬

    2009-01-01

    目的 了解荆州市食品中食源性致病菌的污染状况,为预防和控制食源性疾病提供技术依据. 方法 参照中华人民共和国国家标准GB/T4789-2003(以下简称"国标")以及中国疾病预防控制中心营养与食品安全所颁发的有关检测程序,对荆州市6类食品进行了沙门氏菌、单增李斯特菌、大肠埃希氏菌O157;H_7、副溶血性弧菌、金黄色葡萄球菌和空肠弯曲菌的检测分析. 结果 在119份样品中检出致病菌20株,总检出率为16.8%.其中沙门氏菌检出率13.4%(16/119),副溶血性弧菌检出率9.1%(1/11),金黄色葡萄球菌检出率5.9%(1/17),大肠埃希氏菌O157;H_7检出率1.3%(1/75),单增李斯特氏菌检出率0.8%(1/119),未检出空肠弯曲菌.致病菌检出率最高的为生畜肉,为40.5%(15/37),生禽肉为13.3%(2/15),水产品为8.3%(1/12)、面米食品为11.8%(2/17),即时食品和蔬菜沙拉均未检出致病菌. 结论 荆州市食品食源性致病菌生畜肉和水产品的污染较为严重,应引起有关部门的重视,以防止食源性疾病的发生.%Objective To ascertain food contamination by food-borne pathogens in the City of Jingzhou as a technical basis for prevention and control of food-borne illness. Methods Referring to Chinese National Standard GB/T4789-2003 for Microbiological Testing of Food Sanitation (hereinafter referred to as "GB") as well as relevant testing procedures for Nutrition and Food Safety from the Chinese CDC, six types of food (raw meat, raw poultry, seafood, instant foods, vegetables/salads, foods made from rice or flour) were tested for Salmonella, L. monocytogenes, Escherichia colt O157: H_7 , Vibrio parahaemolyticus , Staphylococcus aureus , and Campylobacter jejuni. Results Twenty pathogens were detected in 119 samples, with a total detection rate of 16. 8 %. Pathogens were Salmonella, with a detection rate of 13.4% (11/119) ; V. parahaemolyticus, with a detection rate of 9. 1 % (1/11) ; S. aureus, with a

  11. Discovery of novel biopreservation agents with inhibitory effects on growth of food-borne pathogens and their application to seafood products.

    Science.gov (United States)

    Chahad, Ouissal Bourouni; El Bour, Monia; Calo-Mata, Pilar; Boudabous, Abdellatif; Barros-Velàzquez, Jorge

    2012-01-01

    Selection of protective cultures is relevant in order to biopreserve and improve the functional safety of food products, mainly through inhibition of spoilage and/or pathogenic bacteria. Accordingly, the present study investigated potential applications of lactic acid bacteria (LAB) in the biopreservation of fish and shellfish products. For this purpose, a collection of 84 LAB strains isolated from sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) was identified and characterized for their inhibitory activities against the most relevant seafood-spoilage and pathogenic bacteria potentially present in commercial products. The bioactive strains belonged to the genus Enterococcus and exhibited inhibition against Carnobacterium sp, Bacillus sp, Listeria monocytogenes, Aeromonas salmonicida, Aeromonas hydrophila and Vibrio anguillarum. Treatment of cell-free extracts of the LAB strains with proteases revealed the proteinaceous nature of the inhibition. Interestingly, the cell-free extracts containing bacteriocins remained 100% active after treatment up to 100 °C for 30 min or 121 °C for 15 min. Molecular analysis led to identification of the bacteriocins investigated, including enterocins A, B, L50 and P. All of these proteins demonstrated remarkable anti-Listeria activity and were found to be heat-resistant small class IIa bacteriocins. The results presented in this work open the way for potential applications of these LAB strains to the biopreservation of minimally-processed seafood products.

  12. 湖北省随州市2009年-2011年食源性致病菌污染状况分析%Analysis of contamination status of food-borne pathogens in Suizhou from 2009 to 2011

    Institute of Scientific and Technical Information of China (English)

    郭芳; 黄晓敏; 彭斌; 王永光; 李月; 刘晓辉; 陈平

    2012-01-01

    目的:了解随州市食品中致病菌的污染现状,确定污染来源,掌握和分析我市食品安全状况,及时发现食品安全隐患,为食品风险做好预警.方法:依据GB/T4789-2008和GB/T4789-2010检测标准和国家食源性致病菌监测工作手册,对2009年-2011年在全市采集的10类食品进行沙门菌、单增李斯特菌、金黄色葡萄球菌、副溶血性弧菌、EHEC O157:H7五种致病菌的检测.结果:检测的424份样品中,致病菌的总检出率为8.96% (38/424),其中金黄色葡萄球菌检出率最高5.73%(20/349),单增李斯特菌检出率3.22%(11/342),副溶血弧菌检出率3.03%(1/33);EHEC O157:H7检出率0.94% (2/212);沙门菌检出率0.94% (4/424);未检出空肠弯曲菌.10类食品中致病菌阳性检出率最高的为速冻米面食品占14.55%,其次为生畜(禽)肉占14.29%,凉拌菜占13.04%,豆制品占11.43%等.结论:随州市居民主要消费食品存在食源性致病菌污染,其中速冻米面、生禽(畜)肉、凉拌菜、豆制品等是主要受污染的食品品种.金黄色葡萄球菌、单增李斯特菌是随州市食源性疾病发生的危险因素.%Objective: To understand the contamination status of food - borne pathogens in food in Suizhou, to i-dentify the source of pollutions and grasp the food security situation, and to discover hidden troubles for food safety. Methods: From 2009 to 2011, according to GB/T4789 -2008,GB/T4789 -2010 and national food - borne pathogenic bacteria monitoring manual, Salmonella, Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemo-lyticus, EHEC 0157:H7 were detected in 10 kinds of food. Results: Among the 424 test samples, the overall detection rate was 8.96% (38/424) , in which Staphylococcus aureus was the highest (5.73% , 20/349) , Listeria monocytogenes detection rate was 3.22% (11/342) , Vibrio parahaemolyticus was 3.03% (1/33) , EHEC 0157: H7 was 0. 94% (2/212) , Salmonella was 0.94% (4/424) , while

  13. Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Ioannis eDiakogiannis

    2013-06-01

    Full Text Available This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH, the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (Tm of cellular lipids of each adapted culture was measured and compared with unexposed cells. The Tm of extracted lipids was measured by Differential Scanning Calorimetry (DSC. A trend of increasing Tm values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in Tm value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased Tm values were measured. The Tm changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased Tm. Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

  14. Chemical composition and in vitro antibacterial activity of essential oil and methanol extract of Echinophora platyloba D.C against some of food-borne pathogenic bacteria.

    Science.gov (United States)

    Hashemi, Mohammad; Ehsani, Ali; Hosseini Jazani, Nima; Aliakbarlu, Javad; Mahmoudi, Razzaqh

    2013-01-01

    Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and investigation of the antibacterial effects of essential oil as well as methanol extract from aerial part of Echinophora Platyloba D.C against S. aureus, L. monocytogenes, S. Thyphimurium and E. coli. Chemical analysis using gas chromatography and mass spectrophotometry (GC/MS) showed that ocimene (26.51%), 2,3-Dimethyl-cyclohexa-1,3-diene (9.87%), alpha-pinene (7.69%) and gamma-dodecanolactone (5.66%) were dominant components of essential oil and the main constituents of methanol extract were o-Cymene (28.66%), methanol (8.50%), alpha-pinene (7.42%) and gamma-decalactone (5.20%). The essential oil showed strong antimicrobial activity against tested bacteria, whereas the methanol extract almost remained inactive against gram-negative bacteria. The most sensitive bacteria to essential oil and extract of Echinophora Platyloba D.C were L. mono-cytogenes and S. aureus. Minimum inhibitory concentration (MIC) values of essential oil against L. monocytogenes and S. aureus were 6250 and 12500 ppm, respectively. MIC of methanol extract against S. aureus and L. monocytogenes was 25000 ppm. Therefore, purifying and evaluation of antibacterial effects of the active substances of the essential oil and methanol extract of this plant for future application as antibacterial agents and food preservatives to combat pathogenic and toxigenic microorganisms is recommended.

  15. Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid.

    Science.gov (United States)

    Diakogiannis, Ioannis; Berberi, Anita; Siapi, Eleni; Arkoudi-Vafea, Angeliki; Giannopoulou, Lydia; Mastronicolis, Sofia K

    2013-01-01

    This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH), the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (T m) of cellular lipids of each adapted culture was measured and compared with unexposed cells. The T m of extracted lipids was measured by differential scanning calorimetry. A trend of increasing T m values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in T m value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased T m values were measured. The T m changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased T m). Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

  16. Chemical composition and in vitro antibacterial activity of essential oil and methanol extract of Echinophora platyloba D.C against some of food-borne pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Mohammad Hashemi

    2013-06-01

    Full Text Available Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and investigation of the antibacterial effects of essential oil as well as methanol extract from aerial part of Echinophora Platyloba D.C against S. aureus, L. monocytogenes, S. Thyphimurium and E. coli. Chemical analysis using gas chromatography and mass spectrophotometry (GC/MS showed that ocimene (26.51%, 2,3-Dimethyl-cyclohexa- 1,3-diene (9.87%, alpha-pinene (7.69% and gamma-dodecanolactone (5.66% were dominant components of essential oil and the main constituents of methanol extract were o- Cymene (28.66%, methanol (8.50%, alpha-pinene (7.42% and gamma-decalactone (5.20%. The essential oil showed strong antimicrobial activity against tested bacteria, whereas the methanol extract almost remained inactive against gram-negative bacteria. The most sensitive bacteria to essential oil and extract of Echinophora Platyloba D.C were L. mono- cytogenes and S. aureus. Minimum inhibitory concentration (MIC values of essential oil against L. monocytogenes and S. aureus were 6250 and 12500 ppm, respectively. MIC of methanol extract against S. aureus and L. monocytogenes was 25000 ppm. Therefore, purifying and evaluation of antibacterial effects of the active substances of the essential oil and methanol extract of this plant for future application as antibacterial agents and food preservatives to combat pathogenic and toxigenic microorganisms is recommended.

  17. 多重PCR快速检测3种食源性致病菌%Detection of three food-borne pathogenic microorganisms by multiplex PCR

    Institute of Scientific and Technical Information of China (English)

    吴建英; 宋建新; 曹金萍; 涂智杰; 余慧宏; 胡芹; 魏建萍; 潘剑

    2014-01-01

    目的:建立一种能同时检测金黄色葡萄球菌、产单核李斯特菌和沙门菌3种致病菌的多重PCR检测方法。方法采用LB培养液对金黄色葡萄球菌、产单核李斯特菌和沙门菌标准菌株进行增菌。根据金黄色葡萄球菌的nuc基因、产单核李斯特氏菌的hlyA基因、沙门氏菌的invA基因设计引物,通过多重聚合酶链反应(PCR)对上述3种食源性致病菌的目的基因进行扩增,同时对反应体系进行优化。结果对平均浓度为5cfu/ml的金黄色葡萄球菌、产单核李斯特菌和沙门氏菌在LB培养液中进行8h振荡培养,可以检出阳性结果;把金黄色葡萄球菌、产单核李斯特菌、沙门菌、志贺菌、蜡样芽孢杆菌、大肠埃希菌O157、阪崎肠杆菌7种菌混合在一起提取混合基因组DNA进行PCR扩增,显示出很好的特异性结果。结论建立的多重PCR检测方法适用于金黄色葡萄球菌、产单核李斯特菌和沙门菌的快速检测,具有快速、简便、灵敏的特点,可广泛应用于食品卫生检测、食物中毒应急处理和临床检验等领域。%Objective To establish a multiplex PCR method for simultaneous detection of Staphylococcus aures, Listeria monocytogens and Salmonella spp. in food. Methods Staphylococcus aures, Listeria monocytogens, and Salmonella spp. were en-riched by LB medium. The primers were designed according to nuc gene of Staphylococcus aures, hlyA gene of Listeria monocyto-gens and invA gene of Salmonella spp. The target genes of these pathogens in food were amplified by multiplex PCR, whose reac-tion conditions were optimized specifically. Results The multiplex PCR method established in this experiment had high specificity while seven kinds of microorganism DNA were mixed in one PCR reaction tube, and the detection limit of the method was 5 cfu/ml for Staphylococcus aures, Listeria monocytogens and Salmonella spp. Conclusion The multiplex PCR method, which was

  18. Antimicrobial activity of Bacillus subtilis CCTCC M207209 against food-borne pathogens%枯草芽孢杆菌CCTCC M207209对食源性病原菌的抑制作用

    Institute of Scientific and Technical Information of China (English)

    孙卉; 师俊玲

    2009-01-01

    采用杯碟法、对峙培养法和平板对扣法分别检测了枯草芽孢杆菌CCTCC M207209的活菌菌碟、无菌体发酵液、多糖提取液、蛋白质粗提液及其挥发性气体产物对金黄色葡萄球菌、肠球菌、化脓链球菌、大肠杆菌、沙门氏菌等食源性病原菌的抑制作用.结果表明,枯草芽孢杆菌CCTCC M207209的活菌菌碟和发酵液对所有参试病原菌均有显著抑制作用;蛋白质粗提液对除化脓链球菌以外的所有病原菌有显著抑制作用;挥发性气体产物对所有病原菌均无抑制作用;所有抑菌活性物质对金黄色葡萄球菌的抑制作用最强,初步确定其为蛋白类物质.%The antimicrobial effects of the agar plug, cell-free broth, polysaccharide extract, crude protein extract and volatile products of Bacillus subtilis CCTCC M207209 on food-borne pathogens, including Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes, Escherichia coli and Salmonella typhimurium, were investigated by cup-plate method, dual-culture plate method and two-sealed-base-plates method.The cell agar plug and cell-free broth showed significant inhibitory activity against all of the tested pathogens.The crude protein extract showed significant inhibitory activity to most pathogens, except for S.pyogenes.The volatile products of B.subtilis CCTCC M207209 had no inhibitory activity to all pathogens.S.aureus was the most sensitive pathogen to all antimicrobial substances, which was preliminarily identified as proteins.

  19. Food-borne diseases - the challenges of 20 years ago still persist while new ones continue to emerge.

    NARCIS (Netherlands)

    Newell, D.G.; Koopmans, M.; Verhoef, L.; Duizer, E.; Aidara-Kane, A.; Sprong, H.; Opsteegh, M.; Langelaar, M.; Threfall, J.; Scheutz, F.; van der Giessen, J.; Kruse, H.

    2010-01-01

    The burden of diseases caused by food-borne pathogens remains largely unknown. Importantly data indicating trends in food-borne infectious intestinal disease is limited to a few industrialised countries, and even fewer pathogens. It has been predicted that the importance of diarrhoeal disease, mainl

  20. Food-borne diseases - the challenges of 20 years ago still persist while new ones continue to emerge.

    NARCIS (Netherlands)

    Newell, D.G.; Koopmans, M.; Verhoef, L.; Duizer, E.; Aidara-Kane, A.; Sprong, H.|info:eu-repo/dai/nl/222364815; Opsteegh, M.|info:eu-repo/dai/nl/31149305X; Langelaar, M.; Threfall, J.; Scheutz, F.; van der Giessen, J.; Kruse, H.

    2010-01-01

    The burden of diseases caused by food-borne pathogens remains largely unknown. Importantly data indicating trends in food-borne infectious intestinal disease is limited to a few industrialised countries, and even fewer pathogens. It has been predicted that the importance of diarrhoeal disease,

  1. Food-borne diseases - the challenges of 20 years ago still persist while new ones continue to emerge.

    NARCIS (Netherlands)

    Newell, D.G.; Koopmans, M.; Verhoef, L.; Duizer, E.; Aidara-Kane, A.; Sprong, H.|info:eu-repo/dai/nl/222364815; Opsteegh, M.|info:eu-repo/dai/nl/31149305X; Langelaar, M.; Threfall, J.; Scheutz, F.; van der Giessen, J.; Kruse, H.

    2010-01-01

    The burden of diseases caused by food-borne pathogens remains largely unknown. Importantly data indicating trends in food-borne infectious intestinal disease is limited to a few industrialised countries, and even fewer pathogens. It has been predicted that the importance of diarrhoeal disease, mainl

  2. The Agr-like quorum-sensing system regulates sporulation and production of enterotoxin and beta2 toxin by Clostridium perfringens type A non-food-borne human gastrointestinal disease strain F5603.

    Science.gov (United States)

    Li, Jihong; Chen, Jianming; Vidal, Jorge E; McClane, Bruce A

    2011-06-01

    Clostridium perfringens type A strains producing enterotoxin (CPE) cause one of the most common bacterial food-borne illnesses, as well as many cases of non-food-borne human gastrointestinal disease. Recent studies have shown that an Agr-like quorum-sensing system controls production of chromosomally encoded alpha-toxin and perfringolysin O by C. perfringens, as well as sporulation by Clostridium botulinum and Clostridium sporogenes. The current study explored whether the Agr-like quorum-sensing system also regulates sporulation and production of two plasmid-encoded toxins (CPE and beta2 toxin) that may contribute to the pathogenesis of non-food-borne human gastrointestinal disease strain F5603. An isogenic agrB null mutant was inhibited for production of beta2 toxin during vegetative growth and in sporulating culture, providing the first evidence that, in C. perfringens, this system can control production of plasmid-encoded toxins as well as chromosomally encoded toxins. This mutant also showed reduced production of alpha-toxin and perfringolysin O during vegetative growth. Importantly, when cultured in sporulation medium, the mutant failed to efficiently form spores and was blocked for CPE production. Complementation partially or fully reversed all phenotypic changes in the mutant, confirming that they were specifically due to inactivation of the agr locus. Western blots suggest that this loss of sporulation and sporulation-specific CPE production for the agrB null mutant involves, at least in part, Agr-mediated regulation of production of Spo0A and alternative sigma factors, which are essential for C. perfringens sporulation.

  3. Analysis on surveillance results of food borne pathogens in Longyan city in 2014%2014年龙岩市食源性致病菌监测结果分析

    Institute of Scientific and Technical Information of China (English)

    廖亦红; 何云; 林伟; 张彦锋; 曹春远

    2015-01-01

    Objective To understand the situation of food hygiene in Longyan. To determine the distribution of food borne pathogens in food, and provide a scientific basis for the prevention and control of food borne diseases. Methods According to the GB method, we separated food-borne pathogens (Staphylococcus aureus,etc.) from all samples. We tested biochemical reaction (VITEK), serology identification to strains.Results 20 strains of pathogens were separated from 189 various samples, including Staphylococcus aureus, Salmonella, Listeria monocytogenes, Cerea spore bacilli, enterobacter sakazaii and pseudomonas aeruginosa. The overall detectable rate is 10.6%. No diarrheogenic E.coli and vibrio parahaemolyticus were detected. In all 9 kinds of food, the detectable rate of processed meat products is the highest(52.4%), infant formula is the second(33.3%) and take-away meals is the third(16.7%). Conclusion The major contaminated foods are processed meat products and infant formula. The major contaminated bacterium in processed meat products is Staphylococcus aureus (33.3%). The major contaminated bacterium in infant formula is enterobacter sakazaii (16.7%). Our study demonstrated that the pathogens contamination is existing in the food of Longyan city,stronger measures should be taken to prevent the happening of food safety incidents.%目的:了解食品卫生状况,确定食品中食源性病原菌分布情况,为预防和控制食源性疾病提供科学依据。方法依据《2014年国家食品污染物和有害因素风险监测工作手册》,对龙岩市肉制品和婴幼儿配方奶粉等分别进行金黄色葡萄球菌等食源性病原菌的分离培养、生化及血清学鉴定。结果共检测包括预制水产品,即食藻类加工食品,婴幼儿配方奶粉,调理肉制品,熟制动物性水产品等九类样品共189件,共检出致病菌20株,总检出率10.6%。金黄色葡萄球菌、沙门菌、单核细胞增生李斯特菌、蜡样

  4. Rapid determination of three food-borne bacterial pathogens using PCR method%PCR法快速检测三种食源性致病菌的研究

    Institute of Scientific and Technical Information of China (English)

    王攀; 王萍; 高林

    2013-01-01

      Objective To rapidly detect Salmonella spp., Staphylococcus aureus and Shigella spp. in food by PCR. Methods The detection performance of PCR method was compared with that of traditional method by proficiency testing and testing of supermarkets samples. Results The correct rate of PCR method was more than 99%, the false positive rate was less than 1%, and the false negative rate was zero. Conclusion The PCR method is high-effective in testing three food-borne bacterial pathogens, with the advantage of a short de-tection period, which could be applied in present food safety testing.%  目的探讨用 PCR 方法快速检测食品中沙门氏菌(Salmonella spp.)、金黄色葡萄球菌(Staphylococcus aureus)和志贺氏菌(Shigella spp.)的实用性。方法采用能力验证实验和超市样品检测实验对PCR方法与传统检测方法进行比较。结果与传统检测方法相比, PCR方法检测以上三种食源性致病菌的结果准确率达到99%以上,假阳性率低于1%,假阴性率为0。结论 PCR检测方法具有检测周期短等优点,可以在当前的食品安全检测工作中应用推广。

  5. Food-Borne Intestinal Bacterial Pathogens

    OpenAIRE

    Bezirtzoglou, Eugenia; Maipa, Vassiliki; Voidarou, Chrissoula; Tsiotsias, Arsenis; Papapetropoulou, Maria

    2011-01-01

    The foods we eat are rarely sterile. They often provide an ideal environment for microbial survival and growth. Microorganisms present in food can originate from the natural microora of the raw material or can be introduced in the course of harvesting, slaughter, processing, storage and distribution. Microbial growth in foods involves changes including intrinsic or extrinsic factors interacting with the microbial community over time. Undesirable microorganisms in foods can manifest their pre...

  6. Monitoring of Food-borne Pathogens in Ya'an in 2011%2011年雅安市食源性病原菌监测结果分析

    Institute of Scientific and Technical Information of China (English)

    张蓉; 熊建明; 杨振宇

    2012-01-01

    Objective To understand the major pathogens in food - borne illness caused by food contamination in Ya'an ctiy and to improve capabilities of detection, early warning and control of food - borne illness in Ya'an. Methods According to Workbook of Monitoring Food - borne Pathogens in 2011 (Institute of Nutrition and Food Safety, Chinese Centre for Disease Control and Prevention) , 9 kinds of food were detected. Results A total of 180 samples included in 9 kinds (20 samples for each kind) were detected. Coliforms were found in following 8 kinds of food: cooked meat, frozen cooked rice products, ready - to - eat fermented soy products, infant formula powder and infant corn -based complementary food, cakes and biscuits, cold dishes, fresh fruit and vegetable juices, rice noodles, Liangpi, noodles and boxed meal. The detection rates were respectively 25% , 20% , 60% , 10% , 30% , 50% , 40% and 20%. The detection rates of mold in frozen of cooked rice products, pastries and cookies were 100% ; staphyhcoccus aureus in fresh fruit and vegetable juices, 5% ; monocytogenes listeria monocytogenes in frozen cooked rice products, 5%. Salmonella, Escherichia coli 0157, Shigella, Enterobacter sakazakii, Bacillus cereus bacteria were not found in all the samples. Conclusion The sanitary situations of bulks or self - made direct - eat food, such as ready - to - eat fermented soy products, cold dishes, fresh fruit and vegetable juices, frozen cooked rice products, cakes and biscuits are not optimistic.The supervision and regulation of such kinds of food should be strengthened to secure food consumption.%目的 了解雅安市食品污染中引起食源性疾病的重要致病菌,提高雅安地区食源性疾病检测、预警和控制能力.方法 按照中国疾病预防控制中心营养与食品安全所《2011年食源性致病菌监测工作手册》,检测9大类食品.结果 抽检9大类食品各20件,共计180件.熟肉制品、速冻熟制米面制品、即食非发酵性

  7. Difficulties in Diagnosing Food-Borne Botulism

    Directory of Open Access Journals (Sweden)

    Nina Forss

    2012-06-01

    Full Text Available Botulism is a muscle-paralyzing disease caused by neurotoxins (types A–G produced by the bacteria Clostridium botulinum. Symptoms of food-borne botulism most commonly appear 12–36 h after eating contaminated food, but the earliest neurological symptoms may in some cases start abruptly. Here, we report the cases of two patients with food-borne botulism who were admitted to the neurological emergency room as candidates for intravenous thrombolysis for acute stroke.

  8. Difficulties in Diagnosing Food-Borne Botulism

    OpenAIRE

    2012-01-01

    Botulism is a muscle-paralyzing disease caused by neurotoxins (types A–G) produced by the bacteria Clostridium botulinum. Symptoms of food-borne botulism most commonly appear 12–36 h after eating contaminated food, but the earliest neurological symptoms may in some cases start abruptly. Here, we report the cases of two patients with food-borne botulism who were admitted to the neurological emergency room as candidates for intravenous thrombolysis for acute stroke.

  9. Difficulties in diagnosing food-borne botulism.

    Science.gov (United States)

    Forss, Nina; Ramstad, Raimo; Bäcklund, Tom; Lindström, Miia; Kolho, Elina

    2012-05-01

    Botulism is a muscle-paralyzing disease caused by neurotoxins (types A-G) produced by the bacteria Clostridium botulinum. Symptoms of food-borne botulism most commonly appear 12-36 h after eating contaminated food, but the earliest neurological symptoms may in some cases start abruptly. Here, we report the cases of two patients with food-borne botulism who were admitted to the neurological emergency room as candidates for intravenous thrombolysis for acute stroke.

  10. Counterpoint: Is Clostridium difficile a food-borne disease?

    Science.gov (United States)

    Marsh, Jane W

    2013-06-01

    The increase in community associated Clostridium difficile disease paired with recent data on C. difficile in retail foods has led to speculation that C. difficile is a food-borne pathogen. However, there is no current epidemiologic evidence (i.e. restaurant or food-associated outbreaks) to support this hypothesis. Rates of C. difficile recovery from food vary widely across laboratories and may be due to a number of confounding factors. This commentary discusses the results of two published investigations and suggests that higher prevalence rates observed in some food studies may be due to laboratory contamination. The conclusions are that prevalence of C. difficile in retail foods is relatively low and further investigations are required to determine if C. difficile is food-borne.

  11. Analysis of food-borne pathogen contamination situation in retailed food in Guangzhou in 2010%2010年广州市市售食品中食源性致病菌污染情况检测结果分析

    Institute of Scientific and Technical Information of China (English)

    陈佳璇; 夏丹; 林云万; 侯水平; 张健

    2012-01-01

    目的:了解广州市区主要消费食品中食源性致病菌的污染状况,寻找本市引起食源性疾病的重点食品,对可能发生的食源性疾病进行预测和预报.方法:按照“全国食源性致病菌监测计划”检验技术要求提出的检测方法,采集七类食品,检测沙门菌、单核细胞增生李斯特菌、副溶血性弧菌等项目.结果:264份样品中检出致病菌64份,平均检出率为24.24%;副溶血性弧菌检出率为37.50% (24/64);单增李斯特菌检出率为5.91% (14/237);沙门菌检出率为12.12% (32/264).结论:广州市市售食品中食源性致病菌污染较为严重,应加强细菌性食源性疾病的研究分析,做好食品安全预警预报工作.%Objective:To understand the contamination status of food - borne pathogenic bacteria in main food in Guangzhou, find out the pathogen source and predict the food - borne disease. Methods: Based on the standard operation procedures in the handbook of National Surveillance on Food - borne Pathogenic Bacteria, seven kinds of food samples were collected for detection of Salmonella, Listeria monocytogenes and Vibrio parahaemolyticus. Results: 264 samples were detected, 64 strains of pathogens were detected with an overall positive rate of 24. 24% . Vibrio parahaemolyticus had the highest positive rate of 37. 50% (24/64) , Listeria monocytogenes had the positive rate of 5.91% (14/237) , the positive rate of Salmonella was 12.12% (32/264). Conclusion: The contamination status of food - borne pathogenic bacteria in main consumption of food in Guangzhou was serious. The study on risk factors of food - borne disease and the predictive warning on food safety should be enforced.

  12. Monitoring result of food-borne pathogens in Yulin City of Guangxi from 2010-2011%2010-2011年广西玉林市食源性致病菌检测结果

    Institute of Scientific and Technical Information of China (English)

    罗铭; 梁炯明; 叶瑞国; 陆运龙; 彭丽; 宋斌; 张耀平

    2013-01-01

    vegetable juice (7. 69% ) , instant non-fermented bean products (3.70% ) and cooked meat products (3.23% ). Pathogenic bacteria were not found in other samples. [ Conclusion] There are many hidden food safety problems in Yulin City. The food inspection departments should focus on high-risk foods to reduce the incidence of food-borne diseases.

  13. 2011年沧州市食源性致病菌污染状况调查%Investigation on contamination status of food-borne pathogens in Cangzhou City in 2011

    Institute of Scientific and Technical Information of China (English)

    卢俊荣; 王春东; 毕红杰; 李秀芝

    2012-01-01

    [ Objective]To understand the contamination status of pathogens in food in Cangzhou city during 2011, provide a scientific basis for the surveillance of food-borne disease and food poisoning in Cangzhou City. [ Methods ] Based on the National technical guide for food-bome pathogens surveillance (2011), the isolation, biochemical identification and serotype identification of total bacteria counts, coliform group, fungus, Salmonella, Vibrio parahaemolyticus, Bacillus cereus, listeria monocytogenes, Esche-richia coli O157:H7, Staphylococcus aureus, Shigella and Enterobacter sakazakii were conducted in 10 types of food. [Results]24 strains of pathogen were detected in 466 samples, and the detection rate was 1.2% (24/2 030). There were 8 strains of Salmonella with the detection rate of 1. 7% (8/466) , 2 strains of Vibrio parahaemolyticus with the detection rate of 9. 5% (2/21) , 11 strains of Listeria monocytogenes with the detection rate of 2.6% (11/462) , 1 strain of Staphylococcus aureus with the detection rate of 0.2% (1/445) and 2 Bacillus cereus with the detection rate of 2.2% (2/90). Escherichia coli O157: H7, Shigella and Enterobacter sakazakii was not detected. [Conclusion]There exists contamination of food-bome pathogens in food in Cangzhou City during 2011, especially cold dish. Health supervising departments should strengthen the management of food product and sale to prevent the food-borne diseases.%目的 了解2011年沧州市食品中致病菌的污染状况,为该市食源性疾病和食物中毒监测提供科学依据.方法 依据2011年全国食源性致病菌监测技术指南,对10类食品进行菌落总数、大肠菌群、霉菌、沙门菌、副溶血性弧菌、蜡样芽孢杆菌、单核细胞增生李斯特菌、大肠杆菌O157:H7、金黄色葡萄球菌、志贺菌、阪崎肠杆菌等11种致病菌分离、生化及血清型鉴定.结果 466份样品分别检测不同致病菌2 030份,检出致病菌24株,致病菌检出率为1.2% (24

  14. Lab-on-chip for the detection of food borne pathogenic bacteria%微流体芯片技术检测食源性致病菌的应用研究

    Institute of Scientific and Technical Information of China (English)

    陈炯; 屠丽红; 陈艳新; 秦胜营

    2014-01-01

    Objective To set up an onsite protocol for abrupt emergencies of public health e-vents, with both the sensitivity and accuracy of the lab-on-chip(microfluidic chip), for the detection of food borne pathogenic bacterium including Vibrio cholera , Salmonella , Vibrio parahaemolyticus and Shigellaare exanimated . [ Methods] By comparison of the results from the chips and fluorescence quantitative PCR were analyzed the specificity , sensitivity, accuracy and repeatability of the Lab-on-chip. [ Results] Acceptable specificity , accuracy and repeatability of the chips had been well achieved , the detection limit of the chips for the Vibrio cholera , Salmonella, Vibrio parahaemolyticus and Shigella was 5 ×103 ~103 DNA Copies/mL. [ Conclusion] Lab-on-chip is believed to be a fast , convenient , efficient tool with accept-able accuracy for public health emergencies .%[目的]通过应用微流体芯片( lab-on-chip)技术检测食源性致病菌,包括霍乱弧菌、沙门菌、副溶血性弧菌、志贺菌等细菌的灵敏度和精确度,从而建立突发公共卫生事件现场实验室的解决方案。[方法]分别采用Lab-on-chip平台食源性病原体微流检测芯片和荧光PCR方法对食源性病原菌样本进行检测,对比分析食源性微流芯片检测方法的特异性、敏感度、准确性和重复性。根据Lab-on-chip说明书以及荧光定量PCP试剂盒操作说明进行操作。[结果] Lab-on-chip方法的霍乱弧菌、沙门菌、志贺菌、副溶血性弧菌检出限为5×103~103 DNA Copies/mL。特异性、准确性和重复性都获得了良好的结果。[结论] Lab-on-chip方法具有快速、便捷、高效、准确等优点,可以在突发公共卫生事件中作为良好的检测工具和方法。

  15. Antimicrobial Activities of Maize Silk Extracts against Food Spoilage and Food-borne Pathogens%玉米须提取物对食品腐败菌及致病菌抑制作用的研究

    Institute of Scientific and Technical Information of China (English)

    纪丽莲; 谭仁祥

    2001-01-01

    Antimicrobial activities of maize (Zea mays. L.) silks extracted with organic solvents were tested against seven food spoilage and food-borne pathogens for the first time.Ethanol (95%,v/v) extracts were ascertained to be the optimum by permitting the maximum yield and the highest antimicrobial activity.The MICs (minimum inhibition concentrations,in g/100g) of maize silk extracts were determined as 1.5 against Escherichia coli,3.0 against Staphylococcus aureus,3.0 against Pseudomonas fluorescens,1.5 against Salmonella typhimurium,2.0 against Bacillus subtilis,2.5 against Bacillus cereus,and 2.0 against Proteus vulgaris,respectively.Influences of food properties including mid-range pH values,storage temperature and time on the activities of the maize extracts were examined.The dependence of the activity on routine food sterilization conditions was measured as well.Therefore,the maize silk extracts could serve as potent,safe and effective food preservatives by means of controlling food properties and processing conditions.%首次以玉米须提取物对7种常见的食品腐败菌及致病菌进行抑菌试验,发现玉米须的乙醇提取物的效果最好,其最低抑菌浓度(MIC)为3.0 g/100g。此外,对食品加工条件(如杀菌方式等)及食品介质(如pH)对玉米须提取物抑菌活性的影响也作了研究。结果表明,玉米须提取物在常规食品杀菌条件(UHT)及中酸到酸性环境下抑菌活性稳定,因而可作为潜在的食品防腐剂。

  16. 徐州市常见食源性致病菌的监测结果分析%Analysis of monitoring results of common food-borne pathogens in Xuzhou

    Institute of Scientific and Technical Information of China (English)

    许静静; 孙永红; 杨晋川; 张雷; 郭惠; 王路梅; 杜阳光; 晏嘉璐; 薛诚; 苗升浩

    2012-01-01

    目的:了解本地区食品中致病菌污染流行情况,为食品安全风险评估,风险预警,针对性的采取控制措施提供依据.方法:根据食品(卫生)微生物学检验国家标准和《食源性致病菌监测工作手册》进行鉴定.结果:总检出率为14.26% (95/666);水产品致病菌检出率最高为25.96%(活鲜冻类28.57%,生食/半生食类23.64%),主要是副溶血性弧菌(22.12%);其次是肉及肉制品为21.28%(生肉31.91%;熟肉10.64%),主要是单增李斯特菌(12.23%);餐饮食品为13.24%,速冻米面食品为13.04%;生食/半生食蔬菜检出率最低(2.27%);生禽肉中沙门菌和水产品中副溶血性弧菌污染菌量高.结论:肉和水产品,食品安全高风险;餐饮食品、速冻米面食品污染较严重;焙烤食品、豆制品等有一定的污染.%Objective: To understand the local prevalence of pathogens in food pollution, and to provide references for food safety risk assessment, risk warning and targeted control measures. Methods: Samples were detected according to national standards of food microbiology testing and " Handbook for Food - borne pathogens surveillance network". Results: The overall detection rate was 14.26% (95/666). The highest rate of pathogenic bacteria was found in aquatic products(25.96% , 28.57% for the fresh and frozen aquatic products, 23.64% for raw food/half raw aquatic products) ,with the highest detection rate in Vibrio parahaemolyticus (22. 12% ) ; then the second highest positive rate of pathogenic bacteria was found in meat and meat products (21. 28% , raw meat accounted for 31.91% ; cooked meats accounted for 10. 64% ) , followed by restaurant food ( 13. 24% ) ,fast - freeze rice and flour food (13. 04% ) , and raw or half cooked vegetables had the lowest detection rate (2. 27% ). Salmonella in raw meat of poultry and Vibrio parahaemolyticus in aquatic products were high volume. Conclusion: Meat and aquatic products had high

  17. Food-borne bacteremic illnesses in febrile neutropenic children.

    Science.gov (United States)

    Lee, Anselm Chi-Wai; Siao-Ping Ong, Nellie Dawn

    2011-08-31

    Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14%) episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets.

  18. Food-borne bacteremic illnesses in febrile neutropenic children

    Directory of Open Access Journals (Sweden)

    Anselm Chi-wai Lee

    2011-08-01

    Full Text Available Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14% episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets.

  19. Antibacterial effect of limonene on food-borne pathogens%柠檬烯对食源性病原菌的抑菌活性(英文)

    Institute of Scientific and Technical Information of China (English)

    卢海燕; 徐重新; 张宵; 梁颖; 刘贤金

    2016-01-01

    研究了柠檬烯乳化液以及柠檬烯丙酮溶液对3种食源性病原菌的抑菌活性.滤纸片扩散试验表明,对小肠结肠炎耶尔森菌Yersinia enterocolitica 的抑菌活性高低为氧氟沙星(阳性对照)>500μL/L 柠檬烯丙酮溶液>5000μL/L柠檬烯丙酮溶液>柠檬烯乳化液>50μL/L 柠檬烯丙酮溶液>丙酮(溶剂对照),抑菌圈分别为46.8 mm,32.2 mm,27.4 mm,17.1 mm,14.5 mm和9.2 mm;对金黄色葡萄球菌Staphylococcusaureus 活性最高的是阳性对照,其次是50μL/L柠檬烯丙酮溶液,抑菌圈达30.3 mm;柠檬烯丙酮溶液对单核增生李斯特菌Listeria monocytogenes 具有抑菌圈,但与丙酮的抑菌圈大小相似,而柠檬烯乳化液未表现出抑菌活性,说明柠檬烯对该菌没有抑制作用,溶剂丙酮具有一定的抑菌活性.试管梯度试验表明,柠檬烯乳化液和柠檬烯丙酮溶液对小肠结肠炎耶尔森菌和金黄色葡萄球菌具有抑菌活性,对单核增生李斯特菌没有活性,且柠檬烯丙酮溶液的最小抑菌浓度和最小杀菌浓度远低于柠檬烯乳化液,说明前者的抑菌活性更好.所选3种食源性病原菌中,小肠结肠炎耶尔森菌对柠檬烯最为敏感,金黄色葡萄球菌次之,单核增生李斯特菌最不敏感.%Summary The effects of limonene emulsion and limonene acetone solution on three species of food-borne pathogens were studied.The results of the agar diffusion test indicated that the order of the antibacterial effect on Yersinia enterocolitica was ofloxacin (positive control)> 500 μL/L limonene acetone solution > 5000 μL/L limonene acetone solution >limonene emulsion > 50μL/L limonene acetone solution > acetone(solvent control),with the inhibition zone diameters of 46.8,32.2,27.4,17.1,14.5,9.2 mm,respectively.Except the positive control,the most effective one on Staphylococcus aureus was 50μL/L limonene acetone solution(the inhibition zone diameter was 30.3 mm).The inhibition zones of limonene acetone solution

  20. Antibiosis of vineyard ecosystem fungi against food-borne microorganisms.

    Science.gov (United States)

    Cueva, Carolina; Moreno-Arribas, M Victoria; Bartolomé, Begoña; Salazar, Óscar; Vicente, M Francisca; Bills, Gerald F

    2011-12-01

    Fermentation extracts from fungi isolated from vineyard ecosystems were tested for antimicrobial activities against a set of test microorganisms, including five food-borne pathogens (Staphylococcus aureus EP167, Acinetobacter baumannii (clinically isolated), Pseudomonas aeruginosa PAO1, Escherichia coli O157:H7 (CECT 5947) and Candida albicans MY1055) and two probiotic bacteria (Lactobacillus plantarum LCH17 and Lactobacillus brevis LCH23). A total of 182 fungi was grown in eight different media, and the fermentation extracts were screened for antimicrobial activity. A total of 71 fungi produced extracts active against at least one pathogenic microorganism, but not against any probiotic bacteria. The Gram-positive bacterium S. aureus EP167 was more susceptible to antimicrobial fungi broth extracts than Gram-negative bacteria and pathogenic fungi. Identification of active fungi based on internal transcribed spacer rRNA sequence analysis revealed that species in the orders Pleosporales, Hypocreales and Xylariales dominated. Differences in antimicrobial selectivity were observed among isolates from the same species. Some compounds present in the active extracts were tentatively identified by liquid chromatography-mass spectrometry. Antimicrobial metabolites produced by vineyard ecosystem fungi may potentially limit colonization and spoilage of food products by food-borne pathogens, with minimal effect on probiotic bacteria.

  1. 湖南省即食食品中食源性致病菌污染状况及耐药性研究%Contamination Status of Food Borne Pathogenic Bacteria in Instant Food in Hunan and Their Antibiotic Resistance

    Institute of Scientific and Technical Information of China (English)

    贾华云; 王岚; 胡旃; 刘建琪; 张林青; 张红

    2013-01-01

    目的 了解湖南地区即食食品中食源性致病菌的污染状况和耐药性,为预防和控制食源性疾病提供科学依据. 方法 从湖南地区的农贸市场、超市和餐饮单位采集即食食品(凉拌菜和熟肉制品),依据GB 4789-2010和GB/T 4789-2008方法,对样品进行沙门菌等4种食源性致病菌检测,分离菌株使用微量肉汤稀释法进行药敏试验. 结果 991份样品共检出食源性致病菌92株,检出率为9.28%,其中检出金黄色葡萄球菌68株,检出率为6.86%,检出沙门菌和单增李斯特菌各12株,检出率为1.21%,未检出大肠埃希菌O157.药敏结果显示金黄色葡萄球菌和沙门菌均具有一定的耐药性,其中金黄色葡萄球菌对苯唑西林的耐药率高达61.76%,而且多重耐药明显. 结论 湖南地区即食食品存在一定的食源性致病菌污染,应加大卫生监督力度,防止食源性疾病的暴发流行;同时应控制动物饲料中抗生素的添加使用,加强抗生素的管理和耐药性监测.%Objective To investigate the contamination status of food borne pathogenic bacteria in instant food in Hunan and to test their antibiotic resistance, so as to provide evidence for the prevention and control of food borne diseases. Methods Salad and cooked meat were collected in food produce markets, supermarkets and catering units in Hunan province. Four food borne pathogenic bacteria including Salmonella in food were identified in accordance with GB 4789 - 2010 and GB/T 4789 -2008. The bacteria were isolated by broth dilution technique to test their drug sensitivity. Results Totally, 92 strains of food borne pathogenic bacteria were identified in 991 food samples, with an incidence of 9.28% . The detection rate of Staphylococcus aureus was 6.86% (68/991). The detection rates of Salmonella and Listeria monocytogenes were both 1.21% (12/991). Es-cherichia coli O157 was not detected. The drug sensitivity test indicated that Staphylococcus aureus and

  2. Interrelationships of food safety and plant pathology: the life cycle of human pathogens on plants.

    Science.gov (United States)

    Barak, Jeri D; Schroeder, Brenda K

    2012-01-01

    Bacterial food-borne pathogens use plants as vectors between animal hosts, all the while following the life cycle script of plant-associated bacteria. Similar to phytobacteria, Salmonella, pathogenic Escherichia coli, and cross-domain pathogens have a foothold in agricultural production areas. The commonality of environmental contamination translates to contact with plants. Because of the chronic absence of kill steps against human pathogens for fresh produce, arrival on plants leads to persistence and the risk of human illness. Significant research progress is revealing mechanisms used by human pathogens to colonize plants and important biological interactions between and among bacteria in planta. These findings articulate the difficulty of eliminating or reducing the pathogen from plants. The plant itself may be an untapped key to clean produce. This review highlights the life of human pathogens outside an animal host, focusing on the role of plants, and illustrates areas that are ripe for future investigation.

  3. Food-borne parasitic zoonoses in China: perspective for control.

    Science.gov (United States)

    Zhou, Peng; Chen, Ning; Zhang, Ren-Li; Lin, Rui-Qing; Zhu, Xing-Quan

    2008-04-01

    Food-borne parasitic zoonoses (FBPZs) cause death and serious diseases in humans and animals worldwide, and are of both public health significance and socioeconomic importance. The FBPZ problem is severe in mainland China, where approximately 150 million people are suffering from FBPZs and more people are at risk. Here, the current status of the FBPZ problem in mainland China is reviewed and strategies and measures for effective control of FBPZs are proposed. Major parasitic zoonoses transmitted through consumption of infected or contaminated meat, fish, plants and/or water will be discussed.

  4. Selected Essential Oils as Antifungal Agents Against Antibiotic-Resistant Candida spp.: In Vitro Study on Clinical and Food-Borne Isolates.

    Science.gov (United States)

    Rajkowska, Katarzyna; Kunicka-Styczyńska, Alina; Maroszyńska, Marta

    2017-01-01

    Candida spp. cause significant health problems, inducing various types of superficial and deep-seated mycoses in humans. As a result of the increasing antibiotic resistance among pathogenic yeasts, the interest in alternative agents of antifungal activity is growing. This study evaluated the antimicrobial activity of selected essential oils (EOs) against Candida clinical and food-borne strains, including antibiotic-resistant isolates, in relation to yeast cell surface hydrophobicity (CSH). Candida strains showed different range of susceptibility to tea tree, thyme, peppermint, and clove oils, and peppermint oil demonstrated the lowest anticandidal activity with minimal inhibitory concentrations (MICs) of 0.03-8.0% v/v. MIC values for thyme and clove oils ranged from 0.03% to 0.25% v/v, and for tea tree oil-from 0.12% to 2.0% v/v. The exception was Candida tropicalis food-borne strain, the growth of which was inhibited after application of EOs at concentration of 8% v/v. Due to diverse yeast susceptibility to EOs, isolates were divided into five clusters in a principal component analysis model, each containing both clinical and food-borne strains. Hydrophobic properties of yeast were also diversified, and 37% of clinical and 50% of food-borne strains exhibited high hydrophobicity. The study indicates high homology of clinical and food-borne Candida isolates in relation to their susceptibility to anticandidal agents and hydrophobic properties. The susceptibility of yeasts to EOs could be partially related to their CSH. High antifungal activity of examined EOs, also against antibiotic-resistant isolates, indicates their usefulness as agents preventing the development of Candida strains of different origin.

  5. 多重PCR技术同时检测四种肠道致病菌方法的建立与初步应用%Establishment and primary application of multiplex polymerase chain reaction for synchronous detection of four food-borne pathogens

    Institute of Scientific and Technical Information of China (English)

    陈琼; 周昱; 孔繁德; 吴德峰; 赵冉; 徐淑菲; 连玉华; 杨涛

    2013-01-01

    Objective To establish a method for detection of four species of food-borne pathogens syn-chronously by multiplex PCR. Methods Four pairs of suitable primers were designed according to the spe-cific gene fimA of Salmonella spp, gene ldh of Citrobacter freundii , gene idsC of Proteus mirabilis, and gene fimA of Edwardsiella tarda. The reaction conditions of multiplex PCR were optimized as well. Results The detection for real samples proved that the multiplex PCR method had the advantages of reliability, sensitivity and rapidness. Conclusion This method can provide a key technical support for developing a kit that detects the four species of food-borne pathogens rapidly.%  目的建立同时检测4种食源性肠道致病菌的多重 PCR方法。方法分别依据沙门氏菌(Salmonella spp)的fimA基因、弗氏枸橼酸杆菌(Citrobacter freundii)的ldh基因、奇异变形杆菌(Proteus mirabilis)的idsC基因、迟缓爱德华菌(Edwardsiella tarda)的fimA基因设计4对特异性引物,并对多重PCR反应条件进行优化。结果建立的多重PCR方法具有结果可靠、灵敏度高、方便快捷的优点。结论本研究为研发快速检测以上4种食源性肠道致病菌的试剂盒提供了重要技术保障。

  6. Food-borne botulism: still actual topic

    Science.gov (United States)

    Brola, Waldemar; Fudala, Malgorzata; Gacek, Szymon; Gruenpeter, Pawel

    2013-01-01

    Even though since the mid-1990s the number of food-borne botulism cases has systematically decreased and it now occurs in Poland relatively rarely, it is still a real epidemiological problem. There are about 30 cases of botulism in Poland a year, which ranks Poland the first among the European Union. In most cases the symptomatology of botulism is typical, however it does not always fully coincide with the one described in medical manuals which emphasise the dramatic clinical course of botulism with its frequent fatal consequences. Diagnosis of botulism may be difficult because of its rare prevalence and a variable clinical course, especially in old patients. Authors of this paper describe two cases of botulism and diagnostic problems associated with it. PMID:23391950

  7. Dietary fatty acids and immune response to food-borne bacterial infections.

    Science.gov (United States)

    Harrison, Lisa M; Balan, Kannan V; Babu, Uma S

    2013-05-22

    Functional innate and acquired immune responses are required to protect the host from pathogenic bacterial infections. Modulation of host immune functions may have beneficial or deleterious effects on disease outcome. Different types of dietary fatty acids have been shown to have variable effects on bacterial clearance and disease outcome through suppression or activation of immune responses. Therefore, we have chosen to review research across experimental models and food sources on the effects of commonly consumed fatty acids on the most common food-borne pathogens, including Salmonella sp., Campylobacter sp., Shiga toxin-producing Escherichia coli, Shigella sp., Listeria monocytogenes, and Staphylococcus aureus. Altogether, the compilation of literature suggests that no single fatty acid is an answer for protection from all food-borne pathogens, and further research is necessary to determine the best approach to improve disease outcomes.

  8. 2011年-2013年泰安市婴幼儿食品食源性致病菌污染状况调查%Investigation on contamination of food borne pathogens in infants foods of Tai'an from 2011 to 2013

    Institute of Scientific and Technical Information of China (English)

    郑金华; 张新峰; 陆娟娟

    2014-01-01

    Objective To investigate the contamination of food borne pathogens from infants foods in Tai'an,so as to provide some scientific basis for early warning ofinfants food borne disease and control of food safety management.Methods According to GB4789-2010 and GB/T4789-2003 standard method,we performed iaolatioin,biochemical identification and serological identification of Bacillus cereus,Enterobacter sakazakii,Staphylococcus aureus,in four kinds of infants foods samples,including milk powder,ground rice,nutrient biscuit and flour products.Results We had checked up 220 samples from 2011 to 2013,as a result,there were 34 pathogenic bacteria to be found,(total detection rate was 15.5 %,34/220),involved 27 Bacillus cereus (with detection rate 12.3%,27/220),5 Enterobacter sakazakii (with detection rate 2.3%,5/220),2 Staphylococcus aureus(with detection rate 0.9%,2/220).There was significant difference of the contamination rates in 3 pathogenic bac.teria(x2 =34.668,P <0.001).The contamination rate detected in milk powder was 22.9% (16/70),ground rice 14.3% (8/56),nutrient biscuit 10.5% (6/57),flour products 10.8% (4/37).Conclusion Food borne pathogens contamination existed in infants food in Tai'an,and milk powder is the main contamination food,while the main pathogenic is bacteria Bacillus cereus.%目的 了解泰安市要幼儿食品食源性致病菌污染状况,为要幼儿食源性疾病预警及食品安全管理提供科学依据.方法 依据GB4789-2010及GB/T4789-2003检测程序对婴幼儿食品(包括奶粉、米粉、营养饼干、面制品4类)进行腊样芽孢杆菌、阪崎肠杆菌、金黄色葡萄球菌的分离培养及鉴定.结果 2011年-2013年220份样品中共检出致病菌34株,总检出率为15.5% (34/220).其中腊样芽孢杆菌检出27株,检出率为12.3% (27/220);阪崎肠杆菌检出5株,检出率为2.3% (5/220);金黄色葡萄球菌检出2株,检出率为0.9% (2/220),不同致病菌检出

  9. Food-borne botulism in Argentina.

    Science.gov (United States)

    Rebagliati, Victoria; Philippi, Romina; Tornese, Mariela; Paiva, Analia; Rossi, Laura; Troncoso, Alcides

    2009-05-01

    Botulism is a severe neuroparalytic disease caused by Clostridium botulinum toxins. Although the disease is uncommon it is a cause of great concern due to its high rate of mortality. Food-borne outbreaks of botulism occur worldwide and require immediate public health attention and acute care resources. Analysis of outbreaks showed that the food products most often involved were fermented fish products in Alaska; home-canned food, oil preservation and restaurant sauce in the rest of the United States (US) and in London and; and home-canned vegetables, airtight packed food with inappropriate refrigeration, and aerosols in Argentina. The diagnosis is based only on clinical findings matching the disease and previous exposure to suspicious food. Botulism must be immediately identified as even one case suggests the start of an epidemic and should be treated as a public health emergency. Therefore, the purpose of the following review is to recognize the risks associated with the consumption of potentially dangerous foods, and to encourage prevention by seeking to make all public health professionals aware of the dangers of this potentially lethal disease.

  10. Quercetin Influences Quorum Sensing in Food Borne Bacteria: In-Vitro and In-Silico Evidence.

    Directory of Open Access Journals (Sweden)

    Venkadesaperumal Gopu

    Full Text Available Quorum sensing (QS plays a vital role in regulating the virulence factor of many food borne pathogens, which causes severe public health risk. Therefore, interrupting the QS signaling pathway may be an attractive strategy to combat microbial infections. In the current study QS inhibitory activity of quercetin and its anti-biofilm property was assessed against food-borne pathogens using a bio-sensor strain. In addition in-silico techniques like molecular docking and molecular dynamics simulation studies were applied to screen the quercetin's potentiality as QS inhibitor. Quercetin (80 μg/ml showed the significant reduction in QS-dependent phenotypes like violacein production, biofilm formation, exopolysaccharide (EPS production, motility and alginate production in a concentration-dependent manner. Synergistic activity of conventional antibiotics with quercetin enhanced the susceptibility of all tested pathogens. Furthermore, Molecular docking analysis revealed that quercetin binds more rigidly with LasR receptor protein than the signaling compound with docking score of -9.17 Kcal/mol. Molecular dynamics simulation predicted that QS inhibitory activity of quercetin occurs through the conformational changes between the receptor and quercetin complex. Above findings suggest that quercetin can act as a competitive inhibitor for signaling compound towards LasR receptor pathway and can serve as a novel QS-based antibacterial/anti-biofilm drug to manage food-borne pathogens.

  11. Study and Application on Detection of Four Kinds of Food-Borne Pathogenic Bacteria by Pyrosequencing Technology%焦磷酸测序技术在4种食源性致病菌快速检测中的应用

    Institute of Scientific and Technical Information of China (English)

    赵新; 王永; 兰青阔; 陈锐; 朱珠; 余景会; 李欧静; 郭永泽

    2013-01-01

    The aim of this study was to establish a detection method for identification of food-borne pathogenic bacteria by using pyrosequencing technology. For this, one pair of polymerase chain reaction (PCR) primers and one pyrosequencing sequencing primer of Salmonellla spp, Listeria monocytogenes, Staphylococcus aureus and Shigella cereus was designed, then the pyrosequencing reaction system and conditions was optimized, the sensitivity of this method was arrived at 10 CFU/mL and has been proven to be highly efficiency, rapid, exact and easy handling. The results provide an informative supplement to fast identified food-borne pathogenic bacteria.%为建立一种利用焦磷酸测序技术检测和鉴定沙门氏菌(Salmonellla)、单核细胞增生李斯特菌(Listeria monocytogenes)、金黄色葡萄球菌(Staphylococcus aureus)和志贺氏菌(Shigella)的方法,通过对4种菌毒力靶基因特异性序列的同源性分析,设计出适合焦磷酸测序特异性扩增和测序的引物,摸索出最佳的焦磷酸测序反应体系和反应程序,并建立了4种食源性致病菌焦磷酸测序快速检测方法.此方法以传统国标法的前增菌为前提,而省去了后期生化验证的繁琐过程,大大缩短了检测时间,并且其准确性与传统生化验证完全一致,灵敏度可达10 CFU/mL.结果表明,作者建立的焦磷酸测序检测方法具有高效、快速、精准及操作简便等特点,为食源性致病菌的快速鉴定开辟了广阔的前景.

  12. [Current status of food-borne diseases in Japan].

    Science.gov (United States)

    Kai, Akemi

    2012-08-01

    The current status of food-borne diseases in Japan was described. Although the number of outbreaks caused by Salmonella, Vibrio parahaemolyticus and Escherichia coli(except enterohaemorrhagic E. coli) is decreasing, outbreaks by Campylobacter or Norovirus are increasing.

  13. Enhanced inactivation of food-borne pathogens in ready-to-eat sliced ham by near-infrared heating combined with UV-C irradiation and mechanism of the synergistic bactericidal action.

    Science.gov (United States)

    Ha, Jae-Won; Kang, Dong-Hyun

    2015-01-01

    The objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (NIR) heating and UV irradiation on inactivation of Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in ready-to-eat (RTE) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of NIR heating and UV irradiation. With the inoculation amounts used, simultaneous NIR-UV combined treatment for 70 s achieved 3.62, 4.17, and 3.43 log CFU reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. For all three pathogens, the simultaneous application of both technologies resulted in an additional log unit reduction as a result of their synergism compared to the sum of the reductions obtained after the individual treatments. To investigate the mechanisms of NIR-UV synergistic injury for a particular microorganism in a food base, we evaluated the effect of four types of metabolic inhibitors using the overlay method and confirmed that damage to cellular membranes and the inability of cells to repair these structures due to ribosomal damage were the primary factors related to the synergistic lethal effect. Additionally, NIR-UV combined treatment for a maximum of 70 s did not alter the color values or texture parameters of ham slices significantly (P > 0.05). These results suggest that a NIR-UV combined process could be an innovative antimicrobial intervention for RTE meat products. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Rapid Detection Method of Food-borne Pathogenic Bacteria of Establishment and Application by Multiplex PCR%食源性致病菌快速检测方法的建立与应用

    Institute of Scientific and Technical Information of China (English)

    周明东; 张臣伟; 张海滨; 周霞; 赵宏坤

    2012-01-01

    目的:建立一种快速检测空肠弯曲杆菌、副溶血弧菌和小肠结肠炎耶尔森菌的多重PCR方法,并进行市场采样检测.方法:根据空肠弯曲杆菌的hipO基因、副溶血弧菌的tlh基因和小肠结肠炎耶尔森菌的Ail基因的特异性抗原基因序列,设计3对特异性引物,优化各种工作条件;测定特异性和灵敏度,建立一种多重PCR检测方法,并对秦安农贸市场采集的409份样本进行检测.结果:建立的多重PCR方法可以快速、简便地检测3种目的菌;对6种食源性致病菌的检测结果表明,该方法特异性很好,灵敏度高.空肠弯曲杆菌的检出极限为3.0×101 cfu/mL,副溶血弧菌的捡出极限为6.2×101 cfu/mL,小肠结肠炎耶尔森菌的检出极限为1.5×101 cfu/mL.样本中空肠弯曲杆菌、副溶血弧菌和小肠结肠炎耶尔森菌的阳性率分别为20.8%,1.5%和13.2%.结论:采用该方法可在5h内得到检测结果,具有操作简便,检测周期短,敏感度和特异性高等优点,为进一步开发空肠弯曲杆菌、副溶血孤菌和小肠结肠炎耶尔森菌快速检测试剂盒及其产业化奠定了基础.%Objective: To develop a rapid method for simultaneously detection of Campylobacter jejuni, Vibrio para haemolyticus and Yersinia enterocolitica by multiplexes PCR. And sampling inspection in Market. Methods: According to Characteristic genes sequences of the hipO gene of Campylobacter jejuni, the tlh gene of Vibrio parahaemolylicus and the Ail gene of Yersinia enterocolitica, three pairs of specific primers were screened, the specifcity and sensitivity of this system were evaluated. Many factors of multiplex PCR were optimized. And 409 samples were collected from poultry meat market in Tai'an for detection. Results; The multiplex PCR assay could be simple and rapid to detect those three pathogens, and the detection limits were 3.0×101 cfu/mL for Campylobacter jejuni, 6.2×101 cfu/mL for Vibrio para haemolytwus and 1.5

  15. Study on Rapid Detection Kit of Food-borne Pathogenic Bacterias by the Multiplex PCR%食源性致病菌快速检测试剂盒的研制

    Institute of Scientific and Technical Information of China (English)

    王文娟; 周明东; 姜彦君; 赵宏坤

    2012-01-01

    Objective: To develop a kit for detection of Salmonella spp., Listeria monocytogenes and Sta. Aureus by multiplex PCR. Methods: Characteristic genes such as invA , hlyA and Nuc were chosen as the target genes for duplex PCR system. Many factors of duplex PCR were optimized. Results: The specificity was satisfactory and the sensitivity was up to 4.7 cfu/mL of Salmonella spp., 17 cfu/mL of Listeria monocytogenes and 4.5 cfu/mL of Sta. Aureus in the system. The whole test can be completed in 5 h. Salmonella was detected in 43.1% (25/58) of the samples, whereas L. Monocytogenes and Sta. Aureus were identified in 10.3%(6/58) and 5.2%(3/58), respectively. Conclusion: The detection kit has the superiority in theory and practical application, and also examines three pathogens once. It can be used for food and raw materials' bio-safety monitoring and also can be used in clinical diagnosis.%目的:研制一种快速检测沙门氏菌、金黄色葡萄球菌和单核细胞增生李斯特菌的三重PCR试剂盒,并在山东泰安地区禽肉市场采样检测.方法:以沙门氏菌的invA基因、单增李斯特菌溶血素hlyA基因和金黄色葡萄球菌耐热核酸酶Nuc基因序列作为目的基因片段金黄色葡萄球菌、沙门菌和单核细胞增生李斯特菌的特异性抗原基因序列,分别设计1对引物,优化各种工作条件,建立一种多重PCR诊断试剂盒.结果:该试剂盒特异性好,敏感性高,沙门氏菌检出极限为4.7 cft/mL,单核细胞增生李斯特菌检出极限17 cfu/mL,金黄色葡萄球菌检出极限4.5 cfu/mL,可在5h之内得到检测结果.在山东泰安地区取样58份,其中25份样品中检出沙门氏菌阳性,带染率43.1%;6份样品中检出单增李斯特菌阳性,带染率为10.3%;3份样品中检出金黄色葡萄球菌阳性,带染率为5.2%.结论:建立的试剂盒能同时检测上述3种病原菌,可用于食品及其原料的生物安全监测,也可用于兽医临床诊断.

  16. Food-borne parasitic zoonosis: Distribution of trichinosis in Thailand

    Institute of Scientific and Technical Information of China (English)

    Natthawut Kaewpitoon; Soraya Jatesadapattaya Kaewpitoon; Prasit Pengsaa

    2008-01-01

    Trichinosis is among the most common food-borne parasitic zoonoses in Thailand and many outbreaks are reported each year. This paper investigates the distribution of the disease in regions of north, northeast, central and south Thailand. Between the earliest recorded of outbreak of trichinosis in Mae Hong Son Province in 1962 and 2006, there have been 135 outbreaks involving 7340 patients and 97 deaths in Thailand. The highest number of cases, 557, was recorded in 1983. Most infected patients were in the 35-44 year age group, and the disease occurred more frequently in men than women during 1962-2003, with no significant sex difference during 2004-2006. Outbreaks were most common in the northern areas, especially in rural areas where raw and under-cooked pork and/or wild animals are eaten. Human infections occur annually in northern Thailand during communal feasts celebrating the Thai New Year. Trichinosis causes have been reported every year, supporting the need for planning education programs.

  17. Food-borne parasitic zoonosis: Distribution of trichinosis in Thailand

    Science.gov (United States)

    Kaewpitoon, Natthawut; Kaewpitoon, Soraya Jatesadapattaya; Pengsaa, Prasit

    2008-01-01

    Trichinosis is among the most common food-borne parasitic zoonoses in Thailand and many outbreaks are reported each year. This paper investigates the distribution of the disease in regions of north, north-east, central and south Thailand. Between the earliest recorded of outbreak of trichinosis in Mae Hong Son Province in 1962 and 2006, there have been 135 outbreaks involving 7340 patients and 97 deaths in Thailand. The highest number of cases, 557, was recorded in 1983. Most infected patients were in the 35-44 year age group, and the disease occurred more frequently in men than women during 1962-2003, with no significant sex difference during 2004-2006. Outbreaks were most common in the northern areas, especially in rural areas where raw and under-cooked pork and/or wild animals are eaten. Human infections occur annually in northern Thailand during communal feasts celebrating the Thai New Year. Trichinosis causes have been reported every year, supporting the need for planning education programs. PMID:18567073

  18. Current status of food-borne trematode infections.

    Science.gov (United States)

    Toledo, R; Esteban, J G; Fried, B

    2012-08-01

    Food-borne trematodiases constitute an important group of the most neglected tropical diseases, not only in terms of research funding, but also in the public media. The Trematoda class contains a great number of species that infect humans and are recognized as the causative agents of disease. The biological cycle, geographical distribution, and epidemiology of most of these trematode species have been well characterized. Traditionally, these infections were limited, for the most part, in populations living in low-income countries, particularly in Southeast Asia, and were associated with poverty. However, the geographical limits and the population at risk are currently expanding and changing in relation to factors such as growing international markets, improved transportation systems, and demographic changes. The diagnosis of these diseases is based on parasitological techniques and only a limited number of drugs are currently available for treatment, most of which are unspecific. Therefore, in-depth studies are urgently needed in order to clarify the current epidemiology of these helminth infections and to identify new and specific targets for both effective diagnosis and treatment. In this review, we describe the biology, medical and epidemiological features, and current treatment and diagnostic tools of the main groups of flukes and the corresponding diseases.

  19. 河池市2009-2010年食品中食源性致病菌污染状况调查%The pollution status of food - borne pathogenic bacteria of food in Hechi city during 2009 to 2010

    Institute of Scientific and Technical Information of China (English)

    吴林洪; 韦麒

    2012-01-01

    Objective To understand the pollution status of food - borne pathogenic bacteria in Hechi city. Method According the monitor guide on security and risk foodstuff of Guangxi to collect and detect the food - borne pathogenic bacteria among 259 samples from 12 kinds of foodstuff, the foodstuff picked out from supermarkets and markets. Results 30 bacterium have been found from the 256 samples and the total detection rate was 11. 6% , among them, the detection rate of cakes was the highest (30% ) . The detection rate of meat, fruit juice, fruit salad, aquatic product, refrigerated foodstuff and salad were 27.3%, 23.8%, 14. 3% , 11.4% , 4. 8% and 4. 8% , reseparately. Among the foodstuff, the pollution of staphylococcus au-reus was quite serious, followed by salmonella, the detection rate were 4.6% and 2.7%, reseparately. Conclusions The foodstuff which directly came into the mouth like cake, juice, fruit salad were the main pollution food. Meat and aquatic product can also bring quite high risk to cause food origin disease.%目的 了解河池市市售食品中食源性致病菌的污染状况.方法 按照《广西省食品安全风险监测工作手册》的要求和检验方法,对河池市辖区内几个较大的市场和超市采集12类259份食品进行6类食源性致病菌检测.结果 256份样品中共检出致病菌30株,总检出率为11.6%.其中以蛋糕制品检出率最高,为30.0%,生肉、果汁制品、水果沙拉、水产品、冰冻食品和凉拌菜的检出率分别为27.3%、23.8%、14.3%、11.4%、4.8%和4.8%;食品中以金黄色葡萄球菌污染较严重,其次是沙门菌,检出率分别为4.6%和2.7%.结论 作为直接入口的蛋糕、果汁制品、水果沙拉是我市食品的主要污染品种,生肉和水产品亦有导致食源性疾病的较高风险.

  20. BRASSICA NIGRA AND CUMINUM CYMINUM: INHIBITORS OF FOOD BORNE PATHOGENS

    Directory of Open Access Journals (Sweden)

    Mamta Bhatia

    2012-08-01

    Full Text Available Dried seeds of spices namely Brassica nigra (mustard and Cuminum cyminum (cumin were screened independently, in culture media, in their different forms (aqueous extracts, essential oils and powders against some bacterial strains of spoilage and health significance. Test microorganisms included one gram+ve bacterial strain i.e. Bacillus cereus (MTCC 430 and three gram-ve bacterial strains viz. Enterococcus faecalis (MTCC 439, Psuedomonas aeruginosa (MTCC 1688 and Shigella sonnei (MTCC 2957. Spice agar method was opted for screening antibacterial activities of powdered forms of aforementioned spices at their different concentration levels (0.0, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0 (% (w/v. B.nigra more effectively inhibited bacterial strains in culture media. Minimum inhibitory concentrations (MIC of powdered form of B.nigra were also determined. It was the concentration of spice which arrested the growth of bacterial strain upto 80% level of the total incubation period of 30 days. Agar-well assay was followed for antibacterial screening of aqueous extracts and essential oils of test spices. Aqueous extracts of reference spice samples did not exhibit growth inhibitory zones towards any test bacterial strains. On the other hand, essential oils of B.nigra and C.cyminum showed distinct growth inhibitory zones against all the bacterial strains under observation. Results obtained from agar well assay revealed that essential oil of B.nigra was more potent in inhibiting bacterial strains followed by C. cyminum . It was also noticed that B. cereus (gram+ve was inhibited at lower concentrations of test substances as compared to all the other three gram-ve bacterial strains under investigation.

  1. Invasion mechanisms among emerging food-borne protozoan parasites.

    Science.gov (United States)

    Yoshida, Nobuko; Tyler, Kevin M; Llewellyn, Martin S

    2011-10-01

    Food-borne parasitic diseases, many known to be more prevalent in poor countries with deficient sanitary conditions, are becoming common worldwide. Among the emerging protozoan parasites, the most prominent is Trypanosoma cruzi, rarely reported in the past to be transmitted by the oral route but currently responsible for frequent outbreaks of acute cases of Chagas disease contracted orally and characterized by high mortality. Several other food-borne protozoans considered emerging include the apicomplexans Toxoplasma gondii and Cryptosporidium, as well as Giardia and Entamoeba histolytica. Here, the interactions of these protozoans with the mucosal epithelia of the host are discussed.

  2. An outbreak of food-borne gastroenteritis due to sapovirus among junior high school students.

    Science.gov (United States)

    Usuku, Shuzo; Kumazaki, Makoto; Kitamura, Katsuhiko; Tochikubo, Osamu; Noguchi, Yuzo

    2008-11-01

    The human sapovirus (SaV) causes acute gastroenteritis mainly in infants and young children. A food-borne outbreak of gastroenteritis associated with SaV occurred among junior high school students in Yokohama, Japan, during and after a study trip. The nucleotide sequences of the partial capsid gene derived from the students exhibited 98% homology to a SaV genogroup IV strain, Hu/Angelholm/SW278/2004/SE, which was isolated from an adult with gastroenteritis in Solna, Sweden. An identical nucleotide sequence was detected from a food handler at the hotel restaurant, suggesting that the causative agent of the outbreak was transmitted from the food handler. This is the first description of a food-borne outbreak associated with the SaV genogroup IV strain in Japan.

  3. Food-borne diseases - the challenges of 20 years ago still persist while new ones continue to emerge.

    Science.gov (United States)

    Newell, Diane G; Koopmans, Marion; Verhoef, Linda; Duizer, Erwin; Aidara-Kane, Awa; Sprong, Hein; Opsteegh, Marieke; Langelaar, Merel; Threfall, John; Scheutz, Flemming; van der Giessen, Joke; Kruse, Hilde

    2010-05-30

    The burden of diseases caused by food-borne pathogens remains largely unknown. Importantly data indicating trends in food-borne infectious intestinal disease is limited to a few industrialised countries, and even fewer pathogens. It has been predicted that the importance of diarrhoeal disease, mainly due to contaminated food and water, as a cause of death will decline worldwide. Evidence for such a downward trend is limited. This prediction presumes that improvements in the production and retail of microbiologically safe food will be sustained in the developed world and, moreover, will be rolled out to those countries of the developing world increasingly producing food for a global market. In this review evidence is presented to indicate that the microbiological safety of food remains a dynamic situation heavily influenced by multiple factors along the food chain from farm to fork. Sustaining food safety standards will depend on constant vigilance maintained by monitoring and surveillance but, with the rising importance of other food-related issues, such as food security, obesity and climate change, competition for resources in the future to enable this may be fierce. In addition the pathogen populations relevant to food safety are not static. Food is an excellent vehicle by which many pathogens (bacteria, viruses/prions and parasites) can reach an appropriate colonisation site in a new host. Although food production practices change, the well-recognised food-borne pathogens, such as Salmonella spp. and Escherichia coli, seem able to evolve to exploit novel opportunities, for example fresh produce, and even generate new public health challenges, for example antimicrobial resistance. In addition, previously unknown food-borne pathogens, many of which are zoonotic, are constantly emerging. Current understanding of the trends in food-borne diseases for bacterial, viral and parasitic pathogens has been reviewed. The bacterial pathogens are exemplified by those well

  4. The Food Production Environment and the Development of Antimicrobial Resistance in Human Pathogens of Animal Origin.

    Science.gov (United States)

    Lekshmi, Manjusha; Ammini, Parvathi; Kumar, Sanath; Varela, Manuel F

    2017-03-14

    Food-borne pathogens are a serious human health concern worldwide, and the emergence of antibiotic-resistant food pathogens has further confounded this problem. Once-highly-efficacious antibiotics are gradually becoming ineffective against many important pathogens, resulting in severe treatment crises. Among several reasons for the development and spread of antimicrobial resistance, their overuse in animal food production systems for purposes other than treatment of infections is prominent. Many pathogens of animals are zoonotic, and therefore any development of resistance in pathogens associated with food animals can spread to humans through the food chain. Human infections by antibiotic-resistant pathogens such as Campylobacter spp., Salmonella spp., Escherichia coli and Staphylococcus aureus are increasing. Considering the human health risk due to emerging antibiotic resistance in food animal-associated bacteria, many countries have banned the use of antibiotic growth promoters and the application in animals of antibiotics critically important in human medicine. Concerted global efforts are necessary to minimize the use of antimicrobials in food animals in order to control the development of antibiotic resistance in these systems and their spread to humans via food and water.

  5. The Food Production Environment and the Development of Antimicrobial Resistance in Human Pathogens of Animal Origin

    Science.gov (United States)

    Lekshmi, Manjusha; Ammini, Parvathi; Kumar, Sanath; Varela, Manuel F.

    2017-01-01

    Food-borne pathogens are a serious human health concern worldwide, and the emergence of antibiotic-resistant food pathogens has further confounded this problem. Once-highly-efficacious antibiotics are gradually becoming ineffective against many important pathogens, resulting in severe treatment crises. Among several reasons for the development and spread of antimicrobial resistance, their overuse in animal food production systems for purposes other than treatment of infections is prominent. Many pathogens of animals are zoonotic, and therefore any development of resistance in pathogens associated with food animals can spread to humans through the food chain. Human infections by antibiotic-resistant pathogens such as Campylobacter spp., Salmonella spp., Escherichia coli and Staphylococcus aureus are increasing. Considering the human health risk due to emerging antibiotic resistance in food animal–associated bacteria, many countries have banned the use of antibiotic growth promoters and the application in animals of antibiotics critically important in human medicine. Concerted global efforts are necessary to minimize the use of antimicrobials in food animals in order to control the development of antibiotic resistance in these systems and their spread to humans via food and water. PMID:28335438

  6. Food-borne botulism in the United Kingdom.

    Science.gov (United States)

    McLauchlin, Jim; Grant, K A; Little, C L

    2006-12-01

    Food-borne botulism is a rare but serious disease caused by ingestions of neurotoxin [botulinum neurotoxins (BoNTs)] produced as a result of the growth of the bacterium Clostridium botulinum in foods before consumption. The disease is rare in the United Kingdom, and only 62 cases have been recognized between 1922 and 2005. This report provides a brief review of C. botulinum and food-borne botulism as well as descriptions of the six episodes (33 cases with three deaths) of this disease that occurred in the United Kingdom between 1989 and 2005. The six incidents illustrate the importance of the risk factors of poor processing or storage of commercially prepared foods, improper home preservation of foods and travel to countries where botulism is much more common than in the United Kingdom. Even small outbreaks of food-borne botulism can precipitate a national emergency and inundate public health and acute care provision. This report provides a reminder to public health professions of the occurrence, diagnosis, treatment and control of this rare but serious food-borne disease.

  7. Toxoplasmosis as a food-borne infection

    Science.gov (United States)

    Đurković-Đaković, O.

    2017-09-01

    Toxoplasma gondii is a globally distributed parasite that infects all mammals, including one third of the world population. Long known to cause disease in the developing foetus and in immunosuppressed individuals, a body of data that has emerged in the past decades suggests its role in human pathology may be even more important. The WHO and FAO have recently established toxoplasmosis as a foodborne infection of global concern, with a disease burden the greatest of all parasitic infections. Transmission of toxoplasmosis occurs by ingesting tissue cysts from undercooked meat and meat products, and oocysts from the environment with contaminated fresh produce or water. This review provides an update on the current understanding of toxoplasmosis, focusing on the risk of infection from food of animal origin, with particular reference to the risk in Serbia and the region of South-East Europe.

  8. Food-borne zoonoses, the EU zoonosis legislation and the prospects for food safety and consumer protection during primary animal production.

    Science.gov (United States)

    Smulders, Frans J M; Vågsholm, Ivar; Korkeala, Hannu

    2008-01-01

    Zoonoses are diseases that are transmitted naturally between animals and humans. The control of food-borne zoonoses within the European Union is a prerequisite for assuring a functional internal market and consequently represents an important item on the political agenda. Unfortunately, until recently, gaining a clear view of the current incidence of food-borne zoonoses and the prevalence of its causative agents has been frustrated by the absence of reliable monitoring and reporting systems. Similarly, it has become clear that, Europe wide, one has witnessed only limited success with regard to the control of important food-borne agents such as Salmonella spp. The European Union has adopted legislation to remedy this situation and to control food-borne zoonoses in primary production. This contribution discusses the incentives for introducing EU Directive 2003/99/EC and EU Regulation No. 2160/2003, summarises their essentials and discusses major ramifications of both pieces of legislation for the prevention of food-borne zoonoses. It is concluded that there is reason for cautious optimism concerning human salmonellosis, while for other food-borne zoonoses there should be a call for action.

  9. Preliminary molecular characterization of the human pathogen Angiostrongylus cantonensis

    Directory of Open Access Journals (Sweden)

    He Ai

    2009-10-01

    Full Text Available Abstract Background Human angiostrongyliasis is an emerging food-borne public health problem, with the number of cases increasing worldwide, especially in mainland China. Angiostrongylus cantonensis is the causative agent of this severe disease. However, little is known about the genetics and basic biology of A. cantonensis. Results A cDNA library of A. cantonensis fourth-stage larvae was constructed, and ~1,200 clones were sequenced. Bioinformatic analyses revealed 378 cDNA clusters, 54.2% of which matched known genes at a cutoff expectation value of 10-20. Of these 378 unique cDNAs, 168 contained open reading frames encoding proteins containing an average of 238 amino acids. Characterization of the functions of these encoded proteins by Gene Ontology analysis showed enrichment in proteins with binding and catalytic activity. The observed pattern of enzymes involved in protein metabolism, lipid metabolism and glycolysis may reflect the central nervous system habitat of this pathogen. Four proteins were tested for their immunogenicity using enzyme-linked immunosorbent assays and histopathological examinations. The specificity of each of the four proteins was superior to that of crude somatic and excretory/secretory antigens of larvae, although their sensitivity was relatively low. We further showed that mice immunized with recombinant cystatin, a product of one of the four cDNA candidate genes, were partially protected from A. cantonensis infection. Conclusion The data presented here substantially expand the available genetic information about the human pathogen A. cantonensis, and should be a significant resource for angiostrongyliasis researchers. As such, this work serves as a starting point for molecular approaches for diagnosing and controlling human angiostrongyliasis.

  10. Listeriosis in animals, its public health significance (food-borne zoonosis) and advances in diagnosis and control: a comprehensive review.

    Science.gov (United States)

    Dhama, Kuldeep; Karthik, Kumaragurubaran; Tiwari, Ruchi; Shabbir, Muhammad Zubair; Barbuddhe, Sukhadeo; Malik, Satya Veer Singh; Singh, Raj Kumar

    2015-01-01

    Listeriosis is an infectious and fatal disease of animals, birds, fish, crustaceans and humans. It is an important food-borne zoonosis caused by Listeria monocytogenes, an intracellular pathogen with unique potential to spread from cell to cell, thereby crossing blood-brain, intestinal and placental barriers. The organism possesses a pile of virulence factors that help to infect the host and evade from host immune machinery. Though disease occurrence is sporadic throughout the world, it can result in severe damage during an outbreak. Listeriosis is characterized by septicaemia, encephalitis, meningitis, meningoencephalitis, abortion, stillbirth, perinatal infections and gastroenteritis with the incubation period varying with the form of infection. L. monocytogenes has been isolated worldwide from humans, animals, poultry, environmental sources like soil, river, decaying plants, and food sources like milk, meat and their products, seafood and vegetables. Since appropriate vaccines are not available and infection is mainly transmitted through foods in humans and animals, hygienic practices can prevent its spread. The present review describes etiology, epidemiology, transmission, clinical signs, post-mortem lesions, pathogenesis, public health significance, and advances in diagnosis, vaccines and treatment of this disease. Special attention has been given to novel as well as prospective emerging therapies that include bacteriophage and cytokine therapy, avian egg yolk antibodies and herbal therapy. Various vaccines, including advances in recombinant and DNA vaccines and their modes of eliciting immune response, are also discussed. Due focus has also been given regarding appropriate prevention and control strategies to be adapted for better management of this zoonotic disease.

  11. Lectins in human pathogenic fungi.

    Science.gov (United States)

    Gallegos, Belém; Martínez, Ruth; Pérez, Laura; Del Socorro Pina, María; Perez, Eduardo; Hernández, Pedro

    2014-01-01

    Lectins are carbohydrate-binding proteins widely distributed in nature. They constitute a highly diverse group of proteins consisting of many different protein families that are, in general, structurally unrelated. In the last few years, mushroom and other fungal lectins have attracted wide attention due to their antitumour, antiproliferative and immunomodulatory activities. The present mini-review provides concise information about recent developments in understanding lectins from human pathogenic fungi. A bibliographic search was performed in the Science Direct and PubMed databases, using the following keywords "lectin", "fungi", "human" and "pathogenic". Lectins present in fungi have been classified; however, the role played by lectins derived from human pathogenic fungi in infectious processes remains uncertain; thus, this is a scientific field requiring more research. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  12. [Food-borne botulism: review of five cases].

    Science.gov (United States)

    Cardoso, Teresa; Costa, Manuela; Almeida, H Cristina; Guimarães, Mário

    2004-01-01

    Food-borne botulism is a disease caused by the ingestion of food contaminated with botulinum toxin, often present in smoked meat, canned food and preserved food; it can occur as sporadic case or as an outbreak. In the last decades there has been an increasing incidence of food-borne botulism in Portugal. The authors do a review of five cases of food-borne botulism, three isolated cases and 2 familiar. Four were associated with the ingestion of smoked ham and one of canned tunafish. The incubation period was 48 hours in one patient and 4 days in another, in the remaining patients it was not possible to determine this period. The clinical picture was dominated in all patients by diplopy, dysphagia, dizziness, blurred vision, dry mouth and constipation, and in two patients there were gastrointestinal complains. In one patient the electromyography findings were compatible with pre-synaptic neuromuscular blockage. A toxin type B was found in the serum of one patient and in the food involved in the two familiar cases. All patients experienced complete recovery with only symptomatic treatment. With this article the authors intend to call attention to this diagnosis, which is not rare, but difficult for someone not familiar with its presentation, being of notice that the diagnosis is essentially clinic with a strong epidemiological history, confirmed by typical electromyography findings and by the identification of the toxin involved. In Portugal there is only descriptions of clinical cases associated with the type B and the type E toxins, not being necessary the resource to the antitoxin therapy.

  13. Detection and sequencing of plasmid encoded tetracycline resistance determinants (tetA andtetB) from food-borneBacillus cereus isolates

    Institute of Scientific and Technical Information of China (English)

    Mudasir Ali Rather; Rabinder Singh Aulakh; Jatinder Paul Singh Gill; Abdul Qayoom Mir; Mir Nadeem Hassan

    2012-01-01

    Objective:To investigate the detection and sequencing of plasmid encoded tetracycline resistance genes(tetA andtetB) from food-borne and standard strains ofBacillus cereus(B. cereus).Methods:APCR was carried out to detect the tetracycline resistance genes(tetA and tetB) in food-borneB. cereus strains and the amplified products were sequenced.Results:The phenotypic resistance against tetracycline was observed in39 of the118 food-borne isolates and two reference strains(MTCC430 andMTCC1307) ofB. cereus.Among the phenotypically resistant isolates,tetA was detected in36 food-borne isolates and two reference strains(MTCC 430 andMTCC1307), whereas,tetB was detected in12 food-borne isolates andMTCC1307 strain. Conclusions:A close association was therefore found between phenotypic resistance against tetracycline and presence of tetracycline resistance genes.ThetetA andtetB gene fragments were amplified, purified and sequenced.The gene sequences of the isolates studied herein were found similar to tetA andtetB gene sequences of other bacteria available inNCBI.The occurrence oftetA and tetB genes inB. cereus indicate the horizontal transfer of antibiotic resistance determinants from other bacteria intoB. cereus.The transfer of these resistant determinants to other potentially pathogenic bacteria may be a matter of great concern.

  14. Workshop on the Application of Genomic Tools for the Rapid Molecular Characterization of Bacterial Isolates in Food-borne Disease Outbreak Investigations Ottawa, ON, February 24-25, 2014

    Science.gov (United States)

    2014-05-01

    pathogens by WGS is leading to a shift in paradigm. At the CDC, WGS began with the investigation of the Haiti cholera outbreak in 2010. The CDC is...Workshop on the Application of Genomic Tools for the Rapid Molecular Characterization of Bacterial Isolates in Food-borne Disease Outbreak ...Characterization of Bacterial Isolates in Food-borne Disease Outbreak Investigations Ottawa, ON, February 24-25, 2014

  15. Staphylococcus aureus and Staphylococcal Food-Borne Disease: An Ongoing Challenge in Public Health

    OpenAIRE

    2014-01-01

    Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail ...

  16. From ontology selection and semantic web to an integrated information system for food-borne diseases and food safety.

    Science.gov (United States)

    Yan, Xianghe; Peng, Yun; Meng, Jianghong; Ruzante, Juliana; Fratamico, Pina M; Huang, Lihan; Juneja, Vijay; Needleman, David S

    2011-01-01

    Several factors have hindered effective use of information and resources related to food safety due to inconsistency among semantically heterogeneous data resources, lack of knowledge on profiling of food-borne pathogens, and knowledge gaps among research communities, government risk assessors/managers, and end-users of the information. This paper discusses technical aspects in the establishment of a comprehensive food safety information system consisting of the following steps: (a) computational collection and compiling publicly available information, including published pathogen genomic, proteomic, and metabolomic data; (b) development of ontology libraries on food-borne pathogens and design automatic algorithms with formal inference and fuzzy and probabilistic reasoning to address the consistency and accuracy of distributed information resources (e.g., PulseNet, FoodNet, OutbreakNet, PubMed, NCBI, EMBL, and other online genetic databases and information); (c) integration of collected pathogen profiling data, Foodrisk.org ( http://www.foodrisk.org ), PMP, Combase, and other relevant information into a user-friendly, searchable, "homogeneous" information system available to scientists in academia, the food industry, and government agencies; and (d) development of a computational model in semantic web for greater adaptability and robustness.

  17. Survival of pathogenic and lactobacilli species of fermented olives during simulated human digestion

    Directory of Open Access Journals (Sweden)

    Francisco Noé eArroyo López

    2014-10-01

    Full Text Available The present survey uses a dynamic gastric and small intestinal model to assess the survival of one pathogenic (Escherichia coli O157:H7 EDL 933 and three lactobacilli bacteria with probiotic potential (Lactobacillus rhamnosus GG, Lactobacillus pentosus TOMC-LAB2 and Lactobacillus pentosus TOMC-LAB4 during their passage through the human gastrointestinal tract using fermented olives as the food matrix. The data showed that the survival of the E. coli strain in the stomach and duodenum was very low, while its transit through the distal parts (jejunum and ileum resulted in an increase in the pathogen population. The production of Shiga toxins by this enterohemorrhagic microorganism in the ileal effluents of the in vitro system was too low to be detected by ELISA assays. On the contrary, the three lactobacilli species assayed showed a considerable resistance to the gastric digestion, but not to the intestinal one, which affected their survival, and was especially evident in the case of both L. pentosus strains. In spite of this, high population levels for all assayed microorganisms were recovered at the end of the gastrointestinal passage. The results obtained in the present study show the potential use of table olives as a vehicle of beneficial microorganisms to the human body, as well as the need for good hygienic practices on the part of olive manufacturers in order to avoid the possibility of contamination by food-borne pathogens.

  18. Survival of pathogenic and lactobacilli species of fermented olives during simulated human digestion.

    Science.gov (United States)

    Arroyo-López, Francisco N; Blanquet-Diot, Stéphanie; Denis, Sylvain; Thévenot, Jonathan; Chalancon, Sandrine; Alric, Monique; Rodríguez-Gómez, Francisco; Romero-Gil, Verónica; Jiménez-Díaz, Rufino; Garrido-Fernández, Antonio

    2014-01-01

    The present survey uses a dynamic gastric and small intestinal model to assess the survival of one pathogenic (Escherichia coli O157:H7 EDL 933) and three lactobacilli bacteria with probiotic potential (Lactobacillus rhamnosus GG, L. pentosus TOMC-LAB2, and L. pentosus TOMC-LAB4) during their passage through the human gastrointestinal tract using fermented olives as the food matrix. The data showed that the survival of the E. coli strain in the stomach and duodenum was very low, while its transit through the distal parts (jejunum and ileum) resulted in an increase in the pathogen population. The production of Shiga toxins by this enterohemorrhagic microorganism in the ileal effluents of the in vitro system was too low to be detected by ELISA assays. On the contrary, the three lactobacilli species assayed showed a considerable resistance to the gastric digestion, but not to the intestinal one, which affected their survival, and was especially evident in the case of both L. pentosus strains. In spite of this, high population levels for all assayed microorganisms were recovered at the end of the gastrointestinal passage. The results obtained in the present study show the potential use of table olives as a vehicle of beneficial microorganisms to the human body, as well as the need for good hygienic practices on the part of olive manufacturers in order to avoid the possibility of contamination by food-borne pathogens.

  19. Differential expression profiling of proteomes of pathogenic and commensal strains of Staphylococcus aureus using SILAC

    OpenAIRE

    Manickam, Manisha

    2011-01-01

    Staphylococcus aureus (S. aureus) is the etiological agent of food-borne diseases, skin infections in humans and mastitis in bovines. S. aureus is also known to exist as a commensal on skin, nose and other mucosal surfaces of the host. This symbiotic association is a result of immune dampening or tolerance induced in the host by this pathogen. We proposed the variation in protein expression by commensal and pathogenic strain as an important factor behind the difference in pathogenicity. The i...

  20. Application of bacteriophages in post-harvest control of human pathogenic and food spoiling bacteria.

    Science.gov (United States)

    Pérez Pulido, Rubén; Grande Burgos, Maria José; Gálvez, Antonio; Lucas López, Rosario

    2016-10-01

    Bacteriophages have attracted great attention for application in food biopreservation. Lytic bacteriophages specific for human pathogenic bacteria can be isolated from natural sources such as animal feces or industrial wastes where the target bacteria inhabit. Lytic bacteriophages have been tested in different food systems for inactivation of main food-borne pathogens including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, Salmonella enterica, Shigella spp., Campylobacter jejuni and Cronobacter sakazkii, and also for control of spoilage bacteria. Application of lytic bacteriophages could selectively control host populations of concern without interfering with the remaining food microbiota. Bacteriophages could also be applied for inactivation of bacteria attached to food contact surfaces or grown as biofilms. Bacteriophages may receive a generally recognized as safe status based on their lack of toxicity and other detrimental effects to human health. Phage preparations specific for L. monocytogenes, E. coli O157:H7 and S. enterica serotypes have been commercialized and approved for application in foods or as part of surface decontamination protocols. Phage endolysins have a broader host specificity compared to lytic bacteriophages. Cloned endolysins could be used as natural preservatives, singly or in combination with other antimicrobials such as bacteriocins.

  1. Scientific Opinion on the evaluation of molecular typing methods for major food-borne microbiological hazards and their use for attribution modelling, outbreak investigation and scanning surveillance: Part 2 (surveillance and data management activities

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Biological Hazards (BIOHAZ

    2014-07-01

    Full Text Available Surveillance programmes based on active and harmonised sampling are considered the most suitable for food-borne outbreak investigations, hypothesis generation, early detection of emerging pathogen subtypes, attribution modelling and genetic studies of bacterial populations. Currently, prototype molecular databases are not widely linked and contain limited epidemiological data, therefore development of linkage mechanisms is a priority. A key technical requirement is determination of an agreed threshold value for the level of genetic variation amongst isolates that can still be regarded as epidemiologically-related. Molecular typing data should be coupled with a minimum required set of epidemiological data and datasets should be comparable to facilitate joint analyses in conjunction with human case data. Rules for assembling strain collections and associated provenance data should be agreed and introduced as EU standards. The data collection process and the characteristics of the data repository should ensure reproducibility and maximise compatibility and interoperability between different datasets. Molecular bacterial characterisation developments, particularly Whole Genome Sequencing (WGS, should be harmonised with those used for surveillance in the human population and food industry. Reference methods and materials, including sequence data, should be adopted for typing of food-borne pathogens. Upload of molecular data should only be allowed for approved laboratories and should be subject to External Quality Assessment. Ongoing international oversight is required to ensure a consensual ‘one-health’ approach. The establishment of a joint EFSA-ECDC-EU-RLs committee for the support of cross-sectoral molecular surveillance, with a balance of public health and veterinary expertise and including both epidemiologists and microbiologists is strongly recommended. Revision of the legal basis of programmes for pathogen reduction based on historic

  2. H. pylori infection in patients with food-borne diseases

    Directory of Open Access Journals (Sweden)

    D. A. Lioznov

    2014-01-01

    Full Text Available The objective: to assess clinical features of food-borne diseases in patients with H. pylori infection.Materials and methods: 98 patients with an acute intestinal infection were examined for the presence of helicobacter pylori infection. Clinical and laboratory parameters were estimated in 82 subjects. Patients were distributed to two groups: 41 H. pylori-infected patients (H. pylori IgG antibodies and DNA in feces and41 H. pylori-noninfected patients.Results: in patients with Helicobacter pyloriinfection a higher range of leukocytosis were indicated: 10,7±2,5×109/l vs 8,6±2,6×109/l respectively, р<0,05, and ESR – 16,2±8,7 mm/h vs 11,2±7,8 mm/h respectively, p<0,05. In H. pyloriinfected patients number of bowel movementsand vomitswere indicated more often than those in the control group: (9,4±5,3 vs 6,7±3,6 times/day respectively, р<0,05; and 4,8±3,4 and 1,0±1,4 times/day, р<0,05. Normalization of bowel function was observedearlier in control group compare with H. pylori-infected patients (3,0±0,7 day of disease and 4,4±1,4 day of disease respectively, in р<0,05.Conclusions: H. pylori-infected patients had clinically and laboratory more severe presentation of acute intestinal infection. Clinical improvementin this patientsoccurredat a later date.

  3. Epidemics of emerging animal diseases and food-borne infection problems over the last 5 years in Japan.

    Science.gov (United States)

    Yamane, Itsuro

    2006-10-01

    There have been several emerging animal diseases and food-borne infection problems occurring in Japan over the last 5 years. We describe brief pictures of these epidemics and our control activities. As acute contagious and/or emerging animal diseases, the foot and mouth disease (FMD) outbreak caused by the Pan-Asian topotype of the type O virus occurred in March 2000 after 92 years of FMD-free status. In 2004, four cases of the highly pathogenic avian influenza (HPAI), which was the first outbreak after 79 years, and caused by the H5N1 subtype, were identified. As part of the responses against these outbreaks, all the animals in the affected farms were destroyed, and movement control areas were established around the infected premises, and a nation-wide intensive survey for FMD and HPAI was performed. As for food-borne or feed-borne infections, the first bovine spongiform encephalopathy (BSE) was identified in September 2001 and 19 more cases have been reported until June 2005. A large outbreak of food-borne infection caused by low-fat milk contaminated with enterotoxin A produced by Staphylococcus aureus, involving more than 13,000 patients, occurred in 2000. In 2003, people who consumed uncooked liver and meat from wild boar and deer developed clinical signs of hepatitis caused by the hepatitis E virus. Pork is also suspected as natural source of virus transmission. Early detection of the first cases and rapid action in preventing and controlling the spread of infections are very important combined with proper risk communication about correct information of the diseases.

  4. The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2013

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2015-01-01

    Full Text Available This report of the European Food Safety Authority and the European Centre for Disease Prevention and Control presents the results of the zoonoses monitoring activities carried out in 2013 in 32 European countries (28 Member States and four non-Member States. Campylobacteriosis was the most commonly reported zoonosis. After several years of an increasing European Union (EU trend, the human campylobacteriosis notification rate has stabilised. In food and animals no EU trends were observed and the occurrence of Campylobacter continued to be high in broiler meat at EU level. The decreasing EU trend in confirmed human salmonellosis cases observed in recent years continued. Most Member States met their Salmonella reduction targets for poultry. In foodstuffs, the reported EU-level Salmonella non-compliance in fresh poultry meat decreased. Human listeriosis increased further, showing an increasing EU trend in 2009-2013. In ready-to-eat foods Listeria was seldom detected above the legal safety limit. Also during 2009-2013, a decreasing EU trend was observed in confirmed yersiniosis cases. Positive findings for Yersinia were mainly reported in pig meat and products thereof. The number of confirmed verocytotoxigenic Escherichia coli (VTEC infections in humans increased. VTEC was reported from food and animals. A total of 5,196 food-borne outbreaks, including water-borne outbreaks, were reported in the EU. Most food-borne outbreaks were caused by Salmonella, followed by viruses, bacterial toxins and Campylobacter, whereas in 28.9 % of all outbreaks the causative agent was unknown. Important food vehicles in strong-evidence food-borne outbreaks were eggs and egg products, followed by mixed food, and fish and fish products. The report further summarises trends and sources along the food chain of tuberculosis due to Mycobacterium bovis, Brucella, Trichinella, Echinococcus, Toxoplasma, rabies, Coxiella burnetii (Q fever, West Nile Virus and tularaemia.

  5. Evaluation of the pathogenic potential, antimicrobial susceptibility, and genomic relations of Yersinia enterocolitica strains from food and human origin.

    Science.gov (United States)

    Lucero-Estrada, Cecilia S M; Soria, José Miguel; Favier, Gabriela Isabel; Escudero, María Esther

    2015-11-01

    Yersinia enterocolitica is a food-borne pathogen that causes gastroenteritis with occasional postinfection sequels. This study was aimed to determinate the pathogenic potential, antimicrobial susceptibility, and genomic relationships of Y. enterocolitica strains of different bioserotypes (B/O) isolated from foods and human samples in San Luis, Argentina. Strains obtained by culture were bioserotyped and characterized by phenotypic and genotypic virulence markers, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE). Yersinia enterocolitica was detected in 9.2% of 380 samples, with a distribution of 10.6% (30/284) for food products and 5.2% (5/96) for human samples. Regarding the pathogenic potential, B1A strains of different serotypes were virF(-) ail(-), of which 72.0% (13/18) were ystB(+) with virulence-related phenotypic characteristics. Among B2/O:9 isolates, 75.0% (9/12) exhibited the genotype virF(+) ail(+) ystB(-) along with phenotypic traits associated with virulence; the same genotype was observed in 80.0% (4/5) of B3/O:3 and B3/O:5 strains. By PFGE, it was possible to separate Y. enterocolitica biotypes into 4 clonal groups (A to D) with 23 genomic types, generating a discriminatory index of 0.96. All isolates were susceptible to antimicrobials used for clinical treatment. This study highlights the presence of pathogenic bioserotypes and the high genomic diversity of the Y. enterocolitica strains isolated in our region.

  6. Distribution of food-borne Staphylococcus aureus enterotoxin genes.

    Science.gov (United States)

    Hu, W D

    2016-01-29

    We identified and analyzed 5 new-type enterotoxin genes, including SEj, SEl, SEq, SEm, and SEr, to explore the distribution of 5 enterotoxin genes in Staphylococcus aureus of different origins as well as their correlations and differences. We examined the distribution of the S. aureus enterotoxin genes and their pathogenic mechanisms. A total of 660 specimens were collected from January 2011 to December 2014, and 217 strains of S. aureus were isolated. The template DNA of S. aureus was extracted. The Primer6.0 and Oligo7 software were used to design and synthesize polymerase chain reaction primers. Amplification results were analyzed by electrophoresis, and the amplification products were recovered and sequenced. Thirty-six bacterial strains contained the SEj gene (16.6%), including 15, 8, 8, 4, and 1 strains in fresh meat, quick-frozen food, raw milk, human purulent tissue, and living environment, respectively. Thirty-one bacterial strains contained the SEr gene (14.3%), including 16, 9, and 6 strains in fresh meat, quick-frozen food, and raw milk, respectively. Twenty-one bacterial strains contained the enterotoxin SEq gene (9.7%), including 8, 6, 6, and 1 strains in fresh meat, quick-frozen food, raw milk, and human purulent tissue, respectively. No SEm and SEl genes were detected. Different types of foods carry different types of enterotoxins, providing a basis for quick tracing for food poisoning. Three enterotoxin genes, SEj, SEr, and SEq, showed the highest carrier rate in quick-frozen food. It is imperative to improve their detection in quick-frozen food.

  7. PREVALENCE AND ANTIBIOTIC RESISTANCE OF FOOD BORNE BACTERIAL CONTAMINATION IN SOME EGYPTIAN FOOD food

    Directory of Open Access Journals (Sweden)

    Samy Selim

    2015-09-01

    Full Text Available This study was undertaken to investigate the prevalence and antibiotic resistance of food borne bacterial contamination in some Egyptian food. Total viable bacteria and total coliform bacteriawere isolated from different sources of food; carbohydrates (bread, flour and basbousa, vegetables (outer and inner tissues of potato and outer and inner tissues of cucumber and proteins (mincedmeat, cheese and milk. The study resulted in maximum value of total viable bacteria found in outer tissue of potato 68X104±1.0, while the minimum value found in inner tissues of potato andcucumber. The study resulted in total coliform was maximum value in minced meat 6.4X103±0.3. Basbousa and inner tissue of potato and cucumber were free from coliforms. The ability of isolatesto producing proteolytic enzymes was tested, we found that 326 isolate (63.92% from all isolates had this ability, thus we selected most 2 potent proteolytic isolates. The two isolates were identifiedas Bacillus cereus and Escherichia coli. The identification confirmed by microlog 34.20 system and 16SrRNA for two isolates and the same result was founded. Sensitivity tested for the most potentproteolytic species to 12 of the most commonly used antibiotics in the Egyptian pharmacy. The results showed that all species were sensitive to most of antibiotics, except B. cereus which was strongly susceptible to azteronam and ceftazidim. The data showed that raw meat, cooked food products, and raw milk were most commonly contaminated with foodborne pathogens and many pathogens were resistant to different antibiotics. The study provided useful information for assessment of the possible risk posed to consumers, which has significant public health impact.

  8. The prevalence of pathogenic Yersinia enterocolitica among ...

    African Journals Online (AJOL)

    GREGO

    2007-04-16

    Apr 16, 2007 ... INTRODUCTION. Yersinia enterocolitica is emerging world wide as an ... significant food borne pathogen even though pathogenic isolates have seldom been .... The main risk factors for the morbidity and mortality of diarrhea ...

  9. Assessment of survival of food-borne microorganisms in the food chain by fluorescence ratio imaging microscopy

    DEFF Research Database (Denmark)

    Siegumfeldt, Henrik; Arneborg, Nils

    2011-01-01

    Traditionally, many data on food–borne microorganisms are obtained as an average of a whole population, under the assumption that the individual cells are clonal and therefore identical. However, it is now acknowledged that there may be a large heterogeneity within an isogenic population, and con......Traditionally, many data on food–borne microorganisms are obtained as an average of a whole population, under the assumption that the individual cells are clonal and therefore identical. However, it is now acknowledged that there may be a large heterogeneity within an isogenic population......, and consequently new methods focus on the individual cells. This mini-review will give an overview of the response of food-borne microorganisms; i.e. pathogenic bacteria, lactic acid bacteria, and yeasts, at a single-cell level to various food-related stress conditions, comprising acid-, disinfection-, salt...

  10. The European Union Summary Report on Trends and Sources of Zoonoses, Zoonotic Agents and Food-borne Outbreaks in 2012

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2014-02-01

    Full Text Available The European Food Safety Authority and the European Centre for Disease Prevention and Control analysed information submitted by 27 European Union Member States on the occurrence of zoonoses and food-borne outbreaks in 2012. Campylobacteriosis was the most commonly reported zoonosis, with 214,268 confirmed human cases. The occurrence of Campylobacter continued to be high in broiler meat at EU level. The decreasing trend in confirmed salmonellosis cases in humans continued with a total of 91,034 cases reported in 2012. Most Member States met their Salmonella reduction targets for poultry. In foodstuffs, Salmonella was most often detected in meat and products thereof. The number of confirmed human listeriosis cases increased to 1,642. Listeria was seldom detected above the legal safety limit from ready-to-eat foods. A total of 5,671 confirmed verocytotoxigenic Escherichia coli (VTEC infections were reported. VTEC was also reported from food and animals. The number of human tuberculosis cases due to Mycobacterium bovis was 125 cases, and 328 cases of brucellosis in humans were reported. The prevalence of bovine tuberculosis in cattle increased, and the prevalence of brucellosis in cattle, sheep or goats decreased. Trichinella caused 301 human cases and was mainly detected in wildlife. One domestically acquired human case and one imported human case of rabies were reported. The number of rabies cases in animals increased compared with 2011. A total of 643 confirmed human cases of Q fever were reported. Almost all reporting Member States found Coxiella burnetii (Q fever positive cattle, sheep or goats. A total of 232 cases of West Nile fever in humans were reported. Nine Member States reported West Nile virus findings in solipeds. Most of the 5,363 reported food-borne outbreaks were caused by Salmonella,bacterial toxins, viruses and Campylobacter, and the main food sources were eggs, mixed foods and fish and fishery products.

  11. Cytotoxic and genotoxic potential of food-borne nitriles in a liver in vitro model

    Science.gov (United States)

    Kupke, Franziska; Herz, Corinna; Hanschen, Franziska S.; Platz, Stefanie; Odongo, Grace A.; Helmig, Simone; Bartolomé Rodríguez, María M.; Schreiner, Monika; Rohn, Sascha; Lamy, Evelyn

    2016-01-01

    Isothiocyanates are the most intensively studied breakdown products of glucosinolates from Brassica plants and well recognized for their pleiotropic effects against cancer but also for their genotoxic potential. However, knowledge about the bioactivity of glucosinolate-borne nitriles in foods is very poor. As determined by GC-MS, broccoli glucosinolates mainly degrade to nitriles as breakdown products. The cytotoxicity of nitriles in human HepG2 cells and primary murine hepatocytes was marginal as compared to isothiocyanates. Toxicity of nitriles was not enhanced in CYP2E1-overexpressing HepG2 cells. In contrast, the genotoxic potential of nitriles was found to be comparable to isothiocyanates. DNA damage was persistent over a certain time period and CYP2E1-overexpression further increased the genotoxic potential of the nitriles. Based on actual in vitro data, no indications are given that food-borne nitriles could be relevant for cancer prevention, but could pose a certain genotoxic risk under conditions relevant for food consumption. PMID:27883018

  12. Monitoring chicken flock behaviour provides early warning of infection by human pathogen Campylobacter.

    Science.gov (United States)

    Colles, Frances M; Cain, Russell J; Nickson, Thomas; Smith, Adrian L; Roberts, Stephen J; Maiden, Martin C J; Lunn, Daniel; Dawkins, Marian Stamp

    2016-01-13

    Campylobacter is the commonest bacterial cause of gastrointestinal infection in humans, and chicken meat is the major source of infection throughout the world. Strict and expensive on-farm biosecurity measures have been largely unsuccessful in controlling infection and are hampered by the time needed to analyse faecal samples, with the result that Campylobacter status is often known only after a flock has been processed. Our data demonstrate an alternative approach that monitors the behaviour of live chickens with cameras and analyses the 'optical flow' patterns made by flock movements. Campylobacter-free chicken flocks have higher mean and lower kurtosis of optical flow than those testing positive for Campylobacter by microbiological methods. We show that by monitoring behaviour in this way, flocks likely to become positive can be identified within the first 7-10 days of life, much earlier than conventional on-farm microbiological methods. This early warning has the potential to lead to a more targeted approach to Campylobacter control and also provides new insights into possible sources of infection that could transform the control of this globally important food-borne pathogen. © 2016 The Authors.

  13. Sexual reproduction of human fungal pathogens.

    Science.gov (United States)

    Heitman, Joseph; Carter, Dee A; Dyer, Paul S; Soll, David R

    2014-08-01

    We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms.

  14. Pyrosequencing analysis of microbial community and food-borne bacteria on restaurant cutting boards collected in Seri Kembangan, Malaysia, and their correlation with grades of food premises.

    Science.gov (United States)

    Abdul-Mutalib, Noor-Azira; Amin Nordin, Syafinaz; Osman, Malina; Ishida, Natsumi; Tashiro, Kosuke; Sakai, Kenji; Tashiro, Yukihiro; Maeda, Toshinari; Shirai, Yoshihito

    2015-05-04

    This study adopts the pyrosequencing technique to identify bacteria present on 26 kitchen cutting boards collected from different grades of food premises around Seri Kembangan, a city in Malaysia. Pyrosequencing generated 452,401 of total reads of OTUs with an average of 1.4×10(7) bacterial cells/cm(2). Proteobacteria, Firmicutes and Bacteroides were identified as the most abundant phyla in the samples. Taxonomic richness was generally high with >1000 operational taxonomic units (OTUs) observed across all samples. The highest appearance frequencies (100%) were OTUs closely related to Enterobacter sp., Enterobacter aerogenes, Pseudomonas sp. and Pseudomonas putida. Several OTUs were identified most closely related to known food-borne pathogens, including Bacillus cereus, Cronobacter sakazaki, Cronobacter turisensis, Escherichia coli, E. coli O157:H7, Hafnia alvei, Kurthia gibsonii, Salmonella bongori, Salmonella enterica, Salmonella paratyphi, Salmonella tyhpi, Salmonella typhimurium and Yersinia enterocolitica ranging from 0.005% to 0.68% relative abundance. The condition and grade of the food premises on a three point cleanliness scale did not correlate with the bacterial abundance and type. Regardless of the status and grades, all food premises have the same likelihood to introduce food-borne bacteria from cutting boards to their foods and must always prioritize the correct food handling procedure in order to avoid unwanted outbreak of food-borne illnesses.

  15. Gastroenteritis and food-borne disease in elderly people living in long-term care.

    Science.gov (United States)

    Kirk, Martyn D; Veitch, Mark G; Hall, Gillian V

    2010-02-01

    Elderly people in long-term care facilities (LTCFs) may be more vulnerable to infectious gastroenteritis and food-borne disease and more likely to experience serious outcomes. We review the epidemiology of gastroenteritis and food-borne diseases in elderly residents of LTCFs to inform measures aimed at preventing sporadic disease and outbreaks. Gastroenteritis in elderly people is primarily acquired from other infected persons and contaminated foods, although infections may also be acquired when residents have poor personal hygiene, have contaminated living environments or water, or have contact with infected pets. Early recognition of outbreaks and implementation of control measures is critical to reduce the effects on LTCF residents and staff members. Although outbreaks among LTCF residents are common, they are challenging to investigate, and there are still major gaps in our knowledge, particularly in regards to controlling noroviruses, the incidence and causes of specific infections, and sources of food-borne disease.

  16. Food-borne trematodiasis: current chemotherapy and advances with artemisinins and synthetic trioxolanes.

    Science.gov (United States)

    Keiser, Jennifer; Utzinger, Jürg

    2007-11-01

    Over 40 million people are infected with food-borne trematodes and 750 million are at risk of food-borne trematodiasis, and yet this tropical disease is neglected. The current arsenal for the treatment and control of food-borne trematodiasis comprises praziquantel and triclabendazole, which were developed 20-30 years ago. The safety, therapeutic profiles and concern about resistance of these two drugs are summarized here. Recent advances with the artemisinins, which are best known for their antimalarial and antischistosomal properties, and the synthetic trioxolanes in different trematode-rodent models are reviewed. Lastly, prospects for the development of a safe, efficacious, inexpensive and broad-spectrum trematocidal drug are considered.

  17. [Endemic, Trend, Research and Direction of Food-borne Parasitic Diseases].

    Science.gov (United States)

    Huang, Yan; Yu, Xin-bing

    2015-12-01

    Food-borne parasitic diseases are exhibiting new epidemiological characteristics in such society that is filled with economic development, ecological environmental changes, more frequent population flow, as well as diversities of dietary source and style. The food-borne parasitic diseases have become a major risk factor for food safety and health care, and a global public health problem. In this review, we will give an overview on the epidemiological information of some major food-borne parasitic diseases both in China and in the world, and summarize their emerging characteristics and epidemiological trends. Research on the prevention techniques and pathogenesis of the diseases is reviewed as well. Finally, perspectives are given on the diagnosis/detection, basic mechanisms of the diseases, and the strategies for prevention and transmission interruption.

  18. Looking in ticks for human bacterial pathogens.

    Science.gov (United States)

    Mediannikov, O; Fenollar, F

    2014-12-01

    Ticks are considered to be second worldwide to mosquitoes as vectors of human diseases and the most important vectors of disease-causing pathogens in domestic and wild animals. A number of emerging tick-borne pathogens are already discovered; however, the proportion of undiagnosed infectious diseases, especially in tropical regions, may suggest that there are still more pathogens associated with ticks. Moreover, the identification of bacteria associated with ticks may provide new tool for the control of ticks and tick-borne diseases. Described here molecular methods of screening of ticks, extensive use of modern culturomics approach, newly developed artificial media and different cell line cultures may significantly improve our knowledge about the ticks as the agents of human and animal pathology.

  19. Host-pathogen Interaction at the Intestinal Mucosa Correlates With Zoonotic Potential of Streptococcus suis

    DEFF Research Database (Denmark)

    Ferrando, Maria Laura; de Greeff, Astrid; van Rooijen, Willemien J. M.;

    2015-01-01

    of SS2 infection. Methods. We developed a noninvasive in vivo model to study oral SS2 infection in piglets. We compared in vitro interaction of S. suis with human and porcine intestinal epithelial cells (IEC). Results. Two out of 15 piglets showed clinical symptoms compatible with S. suis infection 24...... be considered a food-borne pathogen. S. suis interaction with human and pig IEC correlates with S. suis serotype and genotype, which can explain the zoonotic potential of SS2....

  20. Cell entry by human pathogenic arenaviruses.

    Science.gov (United States)

    Rojek, Jillian M; Kunz, Stefan

    2008-04-01

    The arenaviruses Lassa virus (LASV) in Africa and Machupo (MACV), Guanarito (GTOV) and Junin viruses (JUNV) in South America cause severe haemorrhagic fevers in humans with fatality rates of 15-35%. The present review focuses on the first steps of infection with human pathogenic arenaviruses, the interaction with their cellular receptor molecules and subsequent entry into the host cell. While similarities exist in genomic organization, structure and clinical disease caused by pathogenic Old World and New World arenaviruses these pathogens use different primary receptors. The Old World arenaviruses employ alpha-dystroglycan, a cellular receptor for proteins of the extracellular matrix, and the human pathogenic New World arenaviruses use the cellular cargo receptor transferrin receptor 1. While the New World arenavirus JUNV enters cells via clathrin-dependent endocytosis, evidence occurred for clathrin-independent entry of the prototypic Old World arenavirus lymphocytic choriomeningitis virus. Upon internalization, arenaviruses are delivered to the endosome, where pH-dependent membrane fusion is mediated by the envelope glycoprotein (GP). While arenavirus GPs share characteristics with class I fusion GPs of other enveloped viruses, unusual mechanistic features of GP-mediated membrane fusion have recently been discovered for arenaviruses with important implications for viral entry.

  1. Human to human transmission of arthropod-borne pathogens

    NARCIS (Netherlands)

    Martina, Byron E.; Barzon, Luisa; Pijlman, Gorben P.; Fuente, de la José; Rizzoli, Annapaola; Wammes, Linda J.; Takken, Willem; Rij, van Ronald P.; Papa, Anna

    2017-01-01

    Human-to-human (H2H) transmitted arthropod-borne pathogens are a growing burden worldwide, with malaria and dengue being the most common mosquito-borne H2H transmitted diseases. The ability of vectors to get infected by humans during a blood meal to further propel an epidemic depends on complex i

  2. [Isolation of thermostable direct hemolysin producing Vibrio parahaemolyticus from food using screening by PCR in food-borne outbreaks].

    Science.gov (United States)

    Obata, Hiromi; Shimojima, Yukako; Konishi, Noriko; Monma, Chie; Yano, Kazuyoshi; Kai, Akemi; Morozumi, Satoshi; Fukuyama, Masafumi

    2006-07-01

    The producibility of thermostable direct hemolysin (TDH) is the most important pathogenic factor in Vibrio parahaemolyticus. TDH (+) V. parahaemolyticus is usually isolated from patients having V. parahaemolyticus food-borne disease. TDH (+) V. parahaemolyticus is, however, very difficult to isolate from food and environmental samples. In the 5 years from 2000 to 2004 in Tokyo, V. parahaemolyticus was isolated from food samples related to 67 of 227 V parahaemolyticus food-borne outbreaks. In these outbreaks, TDH (+) strains were also tried to isolate using PCR as the screening methods. TDH (+) V. parahaemolyticus strains were able to isolate from enrichment broth in which toxR and tdh genes become positive in PCR. TDH (+) strains of the same serotype with patients were able to be isolated from 23 food samples related to 11 outbreaks (16.4%); 3 outbreaks in 2000, 2 in 2001, 2 in 2002, 1 in 2003, and 3 in 2004. The serotypes of V. parahaemolyticus isolated from food were O3 : K6 (10 samples), O3 : K5 (6 samples), O1 : K25 (4 samples), O3 : K29 (2 samples), O4 : K 8 (1 sample), and O4 : K11 (1 sample). The isolation rate of the TDH (+) strain from enrichment broth differed with samples. In several samples TDH (+) strains were isolated easily only by examining 3 colonies, hence no TDH (+) strains were isolated in spite of the examination of 250 colonies. No correlation was seen between the number of V. parahaemolyticus and the isolation rate of TDH (+) strains in food samples. Screening using PCR is very effective method for isolating TDH (+) V. parahaemolyticus from food samples.

  3. Surveillance of acute infectious gastroenteritis (1992-2009) and food-borne disease outbreaks (1996-2009) in Italy, with a focus on the Piedmont and Lombardy regions.

    Science.gov (United States)

    Mughini-Gras, L; Graziani, C; Biorci, F; Pavan, A; Magliola, R; Ricci, A; Gilli, G; Carraro, E; Busani, L

    2012-02-23

    We describe trends in the occurrence of acute infectious gastroenteritis (1992 to 2009) and food-borne disease outbreaks (1996 to 2009) in Italy. In 2002, the Piedmont region implemented a surveillance system for early detection and control of food-borne disease outbreaks; in 2004, the Lombardy region implemented a system for surveillance of all notifiable human infectious diseases. Both systems are internet based. We compared the regional figures with the national mean using official notification data provided by the National Infectious Diseases Notification System (SIMI) and the National Institute of Statistics (ISTAT), in order to provide additional information about the epidemiology of these diseases in Italy. When compared with the national mean, data from the two regional systems showed a significant increase in notification rates of non-typhoid salmonellosis and infectious diarrhea other than non-typhoid salmonellosis, but for foodborne disease outbreaks, the increase was not statistically significant. Although the two regional systems have different objectives and structures, they showed improved sensitivity regarding notification of cases of acute infectious gastroenteritis and, to a lesser extent, food-borne disease outbreaks, and thus provide a more complete picture of the epidemiology of these diseases in Italy.

  4. Evaluation of a real-time polymerase chain reaction (PCR) assay for detection of anisakis simplex parasite as a food-borne allergen source in seafood products.

    Science.gov (United States)

    Lopez, Itziar; Pardo, Miguel Angel

    2010-02-10

    Anisakis simplex has been recognized as an important cause of disease in humans and as a food-borne allergen source. Actually, this food-borne parasite was recently identified as an emerging food safety risk. An A. simplex -specific primer-probe system based on a real-time polymerase chain reaction (PCR) detection assay has been successfully optimized and validated with seafood samples. In addition, a DNA extraction procedure has been optimized to detect the presence of the nematode in food samples. The assay is a very reliable, specific, and sensitive methodology to detect the presence of traces of this parasite in seafood products, including highly processed samples. As a result, 13 sequences of cytochrome c oxidase II gene were obtained and scrutinized to calculate intra- and interspecific variabilities of 0 and 35-67%, respectively. Finally, an efficiency of 2.07 +/- 0.14 of the assay was calculated, and a limit of detection of 40 ppm parasite in 25 g of sample was also optimized. Actually, the presence of this parasite in several seafood products has been demonstrated, enforcing the necessity of a design for a good manufacturing practice protocol for the processing industry to minimize the presence of this parasite as a food-borne allergen source in seafood products.

  5. Pathogens spectrum of deep human mycosis

    Directory of Open Access Journals (Sweden)

    A. B. Kulko

    2012-01-01

    Full Text Available The article describes characteristics of two different etiology groups of deep human mycosis — extremely dangerous endemic deep mycoses (histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, penicilliosis due to Penicillium marneffei and opportunistic deep mycosis (candidiasis, cryptococcosis, aspergillosis, mucormycosis. Information on fungal pathogens and antifungal agents is presented. The own results of cultural studies obtained during pneumomycosis diagnosis in patients with tuberculosis are shown.

  6. Pathogens spectrum of deep human mycosis

    Directory of Open Access Journals (Sweden)

    A. B. Kulko

    2014-07-01

    Full Text Available The article describes characteristics of two different etiology groups of deep human mycosis — extremely dangerous endemic deep mycoses (histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, penicilliosis due to Penicillium marneffei and opportunistic deep mycosis (candidiasis, cryptococcosis, aspergillosis, mucormycosis. Information on fungal pathogens and antifungal agents is presented. The own results of cultural studies obtained during pneumomycosis diagnosis in patients with tuberculosis are shown.

  7. Pathogenic human viruses in coastal waters

    Science.gov (United States)

    Griffin, Dale W.; Donaldson, Kim A.; Paul, J.H.; Rose, Joan B.

    2003-01-01

    This review addresses both historical and recent investigations into viral contamination of marine waters. With the relatively recent emergence of molecular biology-based assays, a number of investigations have shown that pathogenic viruses are prevalent in marine waters being impacted by sewage. Research has shown that this group of fecal-oral viral pathogens (enteroviruses, hepatitis A viruses, Norwalk viruses, reoviruses, adenoviruses, rotaviruses, etc.) can cause a broad range of asymptomatic to severe gastrointestinal, respiratory, and eye, nose, ear, and skin infections in people exposed through recreational use of the water. The viruses and the nucleic acid signature survive for an extended period in the marine environment. One of the primary concerns of public health officials is the relationship between the presence of pathogens and the recreational risk to human health in polluted marine environments. While a number of studies have attempted to address this issue, the relationship is still poorly understood. A contributing factor to our lack of progress in the field has been the lack of sensitive methods to detect the broad range of both bacterial and viral pathogens. The application of new and advanced molecular methods will continue to contribute to our current state of knowledge in this emerging and

  8. Microbial profiling, neural network and semantic web: an integrated information system for human pathogen risk management, prevention and surveillance in food safety

    Science.gov (United States)

    It is estimated that food-borne pathogens cause approximately 76 million cases of gastrointestinal illnesses, 325,000 hospitalizations, and 5,000 deaths in the United States annually. Genomic, proteomic, and metabolomic studies, particularly, genome sequencing projects are providing valuable inform...

  9. Food-borne norovirus-outbreak at a military base, Germany, 2009

    Directory of Open Access Journals (Sweden)

    Hoehne Marina

    2010-02-01

    Full Text Available Abstract Background Norovirus is often transmitted from person-to-person. Transmission may also be food-borne, but only few norovirus outbreak investigations have identified food items as likely vehicles of norovirus transmission through an analytical epidemiological study. During 7-9 January, 2009, 36 persons at a military base in Germany fell ill with acute gastroenteritis. Food from the military base's canteen was suspected as vehicle of infection, norovirus as the pathogen causing the illnesses. An investigation was initiated to describe the outbreak's extent, to verify the pathogen, and to identify modes of transmission and source of infection to prevent further cases. Methods For descriptive analysis, ill persons were defined as members of the military base with acute onset of diarrhoea or vomiting between 24 December 2008, and 3 February 2009, without detection of a pathogen other than norovirus in stools. We conducted a retrospective cohort study within the headquarters company. Cases were military base members with onset of diarrhoea or vomiting during 5-9 January. We collected information on demographics, food items eaten at the canteen and contact to ill persons or vomit, using a self-administered questionnaire. We compared attack rates (AR in exposed and unexposed persons, using bivariable and multivariable logistic regression modelling. Stool specimens of ill persons and canteen employees, canteen food served during 5-7 January and environmental swabs were investigated by laboratory analysis. Results Overall, 101/815 (AR 12.4% persons fell ill between 24 December 2008 and 3 February 2009. None were canteen employees. Most persons (n = 49 had disease onset during 7-9 January. Ill persons were a median of 22 years old, 92.9% were male. The response for the cohort study was 178/274 (72.1%. Of 27 cases (AR 15.2%, 25 had eaten at the canteen and 21 had consumed salad. Salad consumption on 6 January (aOR: 8.1; 95%CI: 1.5-45.4 and 7

  10. Salt induces biosynthesis of hemolytically active compounds in the xerotolerant food-borne fungus Wallemia sebi.

    Science.gov (United States)

    Botić, Tanja; Kunčič, Marjetka K; Sepčić, Kristina; Knez, Zeljko; Gunde-Cimerman, Nina

    2012-01-01

    Wallemia sebi is a xerotolerant, ubiquitous, food-borne, mycotoxigenic fungus. An ethanol extract of its mycelium demonstrated a strong hemolytic activity, which was further enhanced at high salt concentrations in the growth medium. Characterization of the extract using gas chromatography-mass spectrometry revealed a mixture of sterols and unsaturated fatty acids, indicating the latter as responsible for the hemolytic activity. The lytic activity of the extract is here studied using red blood cells and artificial small lipid vesicles with various lipid compositions. This shows concentration-dependent hemolysis and preferential activity toward lipid membranes with greater fluidity. The W. sebi lytic activity on mammalian erythrocytes shows its potential involvement in the formation of lesions in subcutaneous infections, in farmer's lung disease, and in consumption of food and feed that are contaminated with food-borne W. sebi.

  11. Adhesion of human pathogenic enteric viruses and surrogate viruses to inert and vegetal food surfaces.

    Science.gov (United States)

    Deboosere, Nathalie; Pinon, Anthony; Caudrelier, Yvette; Delobel, Alexandre; Merle, Ghislaine; Perelle, Sylvie; Temmam, Sarah; Loutreul, Julie; Morin, Thierry; Estienney, Marie; Belliot, Gael; Pothier, Pierre; Gantzer, Christophe; Vialette, Michèle

    2012-10-01

    Enteric viruses, particularly human Noroviruses (NoV) and hepatitis A virus (HAV), are key food-borne pathogens. The attachment of these pathogens to foodstuff and food-contact surfaces is an important mechanism in the human contamination process. Studies were done to investigate the nature of the physicochemical forces, such as hydrophobic and electrostatic ones, involved in the interaction virus/matrix but, at this day, only few data are available concerning surface properties of viruses and prediction of the adhesion capacity of one specific virus onto matrices is still very difficult. The purpose of this study was to propose a reference system, including a representative virus surrogate, able to predict as close as possible behaviour of pathogenic viruses in term of adhesion on inert (stainless steel and polypropylene) and food surfaces (lettuce leaves, strawberries and raspberries). The adhesion of human pathogenic enteric viruses, cultivable strain of HAV and non-cultivable strains of human NoV (genogroups I and II), have been quantified and compared to these of human enteric viruses surrogates, included the MNV-1 and three F-specific RNA bacteriophages (MS2, GA and Qβ). A standardized approach was developed to assess and quantify viral adhesion on tested matrices after a contact time with each virus using real-time RT-PCR. Methods used for virus recovery were in accordance with the CEN recommendations, including a bovine Enterovirus type 1 as control to monitor the efficiency of the extraction process and amplification procedure from directly extracted or eluted samples. The adhesion of human pathogenic viruses, ranging from 0.1 to 2%, could be comparable for all matrices studied, except for NoV GII on soft fruits. Adhesion percentages obtained for the studied surrogate virus and phages were shown to be comparable to those of HAV and NoV on inert and lettuce surfaces. The MNV-1 appeared as the best candidate to simulate adhesion phenomena of all human

  12. Hygienic Practice and Knowledge of food borne diseases in Home Kitchen Handlers

    OpenAIRE

    2015-01-01

    Background: Food borne illness cases may occur due to improperly prepared or mishandled food, unhygienic sanitation and cleaning practice at home by home kitchen handlers. Objective: To explore the knowledge and practice of literate female of Indore city who are dealing with Home kitchen every day. Methodology: A Cross-Sectional study among 160 participants according to their profession (Health sector workers, Non-health sector workers, House Makers and Students) were selected randomly and in...

  13. An outbreak of food-borne botulism in Scotland, United Kingdom, November 2011.

    Science.gov (United States)

    Browning, L M; Prempeh, H; Little, C; Houston, C; Grant, K; Cowden, J M

    2011-12-08

    An investigation is currently underway to explain an outbreak of food-borne botulism in Scotland. Three children in the same family were confirmed as having botulism following consumption of a meal made with a jar of korma sauce. Residual sauce from the jar, the jar lid and a remnant of the meal, all tested positive for Clostridium botulinum type A toxin. The children are recovering, although two remain ventilated and in intensive care unit.

  14. Food-borne trematodiases in Southeast Asia epidemiology, pathology, clinical manifestation and control.

    Science.gov (United States)

    Sripa, Banchob; Kaewkes, Sasithorn; Intapan, Pewpan M; Maleewong, Wanchai; Brindley, Paul J

    2010-01-01

    The food-borne trematodiases are an important group of neglected tropical diseases (NTDs). Over 40 million people are infected with food-borne trematodes and 750 million (>10% of the world's population) are at risk of these NTDs. Here, we review the life cycles, epidemiology, clinical manifestations, pathology and pathogenesis, diagnosis, treatment, and prevention and control of the major food-borne trematodiases in Southeast Asia. We focus particularly on opisthorchiasis caused by Opisthorchis viverrini and clonorchiasis caused by Clonorchis sinensis, which people contract by ingestion of metacercariae in flesh of raw or undercooked freshwater fishes, on fascioliasis caused by Fasciola species, where infection arises from ingestion of metacercariae on water plants such as watercress, and on Paragonimus species, the lung flukes, which use freshwater crabs and other crustaceans as intermediate hosts. We also include information on the intestinal flukes Fasciolopsis buski, the echinostomes and the so-called 'minute intestinal flukes' of the family Heterophyidae. Ecological information, placing emphasis on reservoir hosts, intermediate snail hosts and secondary hosts where applicable, is also reviewed and research needs are highlighted.

  15. RECURRENT EPISODES OF FOOD BORNE BOTULISM IN A 7-YEAR OLD BOY

    Directory of Open Access Journals (Sweden)

    Seddighi MD

    2007-02-01

    Full Text Available Objective Botulism is the acute, descending, flaccid paralysis that results when the neurotoxin of Clostridium botulinum blocks neuromuscular transmission. C botulinum toxin is the most poisonous substance that blocks neuromuscular transmission and causes death through airway and respiratory muscle paralysis; all forms of botulism manifest neurologically as asymmetric, descending, flaccid paralysis beginning with the cranial nerve musculature. Food-borne botulism results from the ingestion of food in which C botulinum has multiplied and produced its toxin.Patient We report a new case of food-borne botulism in a 7 year old boy with recurrent episodes of weakness, difficulty in swallowing and speech; bilateral ptosis and mydriasis. He had positive history of the same symptoms, documented twice before. The patient’s samples were sent for detection of toxin of Clostridium botulinum, and toxin of C. botulinum, type A was found in his stool sample, confirming our diagnosis. This case was unusual report because our patient has not history of canned food ingestion and also because recurrent episodes of paralysis in this case are unusual findings in botulism.ConclusionIn this report we want to emphasize that canned-food ingestion is not necessary for diagnosis of food-borne botulism and because delayed treatment leads to increase mortality and morbidity, treatment should be initiated promptly on the basis of clinical suspicion

  16. An outbreak of food-borne group A Streptococcus (GAS) tonsillopharyngitis among residents of a dormitory.

    Science.gov (United States)

    Sarvghad, M R; Naderi, H R; Naderi-Nassab, M; Majdzadeh, R; Javanian, M; Faramarzi, H; Fatehmanesh, P

    2005-01-01

    Epidemics of food-borne pharyngitis due to group A Streptococcus are rarely reported. Here we present an outbreak of food-borne tonsillopharyngitis in female dormitories in the Islamic Republic of Iran. Throat swabs and cultures were performed on a number of patients, and of specimens from the nasopharynx and hands of staff who were involved in food processing. We planned a case-control study for assessing the source of epidemics. 11 out of 17 throat swabs of students were positive for Streptococcus group A and also 2 throat samples from asymptomatic cooks were positive. A DNA fingerprinting study showed that Streptococcus group A strains of 11 students and 1 cook had the same T agglutination pattern and M protein factor (M3/T13). It is suggested that group A streptococci as well as group C and G streptococci can cause epidemic food-borne pharyngitis. Regular health surveillance of food handlers and food preparation processes are important for prevention of such outbreaks.

  17. Adaptation of the food-borne pathogen Bacillus cereus to carvacrol

    NARCIS (Netherlands)

    Ultee, A.; Kets, E.P.W.; Alberda, M.; Hoekstra, F.A.; Smid, E.J.

    2000-01-01

    Carvacrol, a natural antimicrobial compound present in the essential oil fraction of oregano and thyme, is bactericidal towards Bacillus cereus. A decrease of the sensitivity of B. cereus towards carvacrol was observed after growth in the presence of non-lethal carvacrol concentrations. A decrease o

  18. Real-time PCR Detection of Food-borne Pathogenic Salmonella spp

    DEFF Research Database (Denmark)

    Malorny, B.; Mäde, D.; Löfström, Charlotta

    2013-01-01

    -limiting gastrointestinal disease in a wide range of mammalian hosts. Within the last decade, numerous real-time PCR assays have been developed for rapid detection of salmonellae in potentially contaminated food or feed. Some of them were extensively validated and are useful for diagnostic laboratories. Furthermore......, effective sample preparation prior to the analytical real-time PCR assay avoids inhibitory substances disturbing the PCR and contributes to a high sensitivity. We discuss appropriate sample preparation methods including enrichment procedures for various food items and analytical real-time PCR assays...... for the detection of Salmonella and give a state-of-the-art summary what targets are used and how valid the assays are to apply as diagnostic tool. Furthermore, recommendations for selection of an appropriate real-time PCR method are presented....

  19. Antimicrobial Activity of Kedawung Extract (Parkia Roxburghii G. Don on Food Borne Pathogens

    Directory of Open Access Journals (Sweden)

    Ervizal A. M Zuhud, Winiati Pudji Rahayu, C. Hanny Wijaya, Pipi Puspita Sari

    2001-04-01

    Full Text Available Kedawung is a Leguminosae/Fabaceae which. It is commonly used as traditional medicine for infection and stomach disoders, caused by bacteria.The aim of this study is to examine the potential antimicrobial activity of seed, bark, root and kedawung leaf. It is expected that the result will give information on characteristics and concentration of kedawung part which have the highest antimicrobial activity.The result showed that the bark has the highest antimicrobial activity on Escherichia coli, Vibrio cholerae, Staphylococcus aureus and Bacillus cereus. Extract made from kedawung plant and water (ratio 1:2,b/v was better than those made with ratios of 1 : 1 or 1 : 3 (b/v. Heat did not decrease its antimicrobial activity. Extract concentration of 10% (21.40 mg/ml with contact time of 24 hour decreased bacterial growth but did not inactivate them.

  20. Co-infection dynamics of a major food-borne zoonotic pathogen in chicken

    DEFF Research Database (Denmark)

    Skanseng, Beate; Trosvik, Pal; Zimonja, Monika

    2007-01-01

    , with an important reservoir in the gastrointestinal (GI) tract of chickens, was used as a model. We investigated the co-colonisation dynamics of seven C. jejuni strains in a chicken GI infection trial. The seven strains were isolated from an epidemiological study showing multiple strain infections at the farm level....... We analysed time-series data, following the Campylobacter colonisation, as well as the dominant background flora of chickens. Data were collected from the infection at day 16 until the last sampling point at day 36. Chickens with two different background floras were studied, mature ( treated...... with Broilact, which is a product consisting of bacteria from the intestinal flora of healthy hens) and spontaneous. The two treatments resulted in completely different background floras, yet similar Campylobacter colonisation patterns were detected in both groups. This suggests that it is the chicken host...

  1. Co-infection dynamics of a major food-borne zoonotic pathogen in chicken

    DEFF Research Database (Denmark)

    Skanseng, Beate; Trosvik, Pal; Zimonja, Monika;

    2007-01-01

    with Broilact, which is a product consisting of bacteria from the intestinal flora of healthy hens) and spontaneous. The two treatments resulted in completely different background floras, yet similar Campylobacter colonisation patterns were detected in both groups. This suggests that it is the chicken host....... We analysed time-series data, following the Campylobacter colonisation, as well as the dominant background flora of chickens. Data were collected from the infection at day 16 until the last sampling point at day 36. Chickens with two different background floras were studied, mature ( treated...... and not the background flora that is important in determining the Campylobacter colonisation pattern. Our results showed that mainly two of the seven C. jejuni strains dominated the Campylobacter flora in the chickens, with a shift of the dominating strain during the infection period. We propose a model in which...

  2. Antibiotic resistance and assessment of food-borne pathogenic bacteria in frozen foods.

    Science.gov (United States)

    Baek, Eunhye; Lee, Dokyung; Jang, Seok; An, Hyangmi; Kim, Mijin; Kim, Kyungjae; Lee, Kangoh; Ha, Namjoo

    2009-12-01

    One hundred ninety-three frozen food samples collected in Korea various public bazaars from October 2006 to September 2007. Staphylococci were detected in 21.8% of frozen food samples. Staphylococcus aureus was isolated from 17 (8.8%) samples. Other staphylococci isolates were identified as S. warneri (7.8%), S. epidermidis (2.1%), S. xylosus (1.6%), S. eguorum (1%), and S. vitulinus (0.5%). Additionally, the antimicrobial susceptibility of 42 staphylococcal isolates to ten different antimicrobial agents was determined. The staphylococcal isolates demonstrated antimicrobial resistance to mupirocin (31%) oxacillin (14.3%), gentamicin (9.5%), teicoplanin (7.1%) and ciprofloxacin (7.1%). Most of the staphylococcal isolates showed high-level resistance to mupirocin (MIC(90), >128 microg/mL). Fortunately, most of the isolates were susceptible to vancomycin. The total bacteria and Escherichia coli count were tested to investigate the microbiological quality of frozen foods. From 193 frozen food samples, 43 (22.3%), 34 (17.6%) and 19 (9.8%) samples were shown to be of unacceptable quality due to total bacteria, coliform and E. coli counts, respectively.

  3. Non-thermal plasma-activated water inactivation of food-borne pathogen on fresh produce.

    Science.gov (United States)

    Ma, Ruonan; Wang, Guomin; Tian, Ying; Wang, Kaile; Zhang, Jue; Fang, Jing

    2015-12-30

    Non-thermal plasma has been widely considered to be an effective method for decontamination of foods. Recently, numerous studies report that plasma-activated water (PAW) also has outstanding antibacterial ability. This study presents the first report on the potential of PAW for the inactivation of Staphylococcus aureus (S. aureus) inoculated on strawberries. PAW treatments achieved a reduction of S. aureus ranging from 1.6 to 2.3 log at day-0 storage, while 1.7 to 3.4 log at day-4 storage. The inactivation efficiency depended on the plasma-activated time for PAW generation and PAW-treated time of strawberries inoculated with S. aureus. LIVE/DEAD staining and scanning electron microscopy results confirm that PAW could damage the bacterial cell wall. Moreover, optical emission spectra and oxidation reduction potential results demonstrate the inactivation is mainly attributed to oxidative stress induced by reactive oxygen species in PAW. In addition, no significant change was found in color, firmness and pH of the PAW treated strawberries. Thus, PAW can be a promising alternative to traditional sanitizers applied in the fresh produce industry.

  4. Non-thermal plasma-activated water inactivation of food-borne pathogen on fresh produce

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ruonan; Wang, Guomin; Tian, Ying; Wang, Kaile [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Zhang, Jue, E-mail: zhangjue@pku.edu.cn [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); College of Engineering, Peking University, Beijing 100871 (China); Fang, Jing [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); College of Engineering, Peking University, Beijing 100871 (China)

    2015-12-30

    Highlights: • We propose a new approach to treat S. aureus inoculated on strawberries by PAW. • PAW could inactivate S. aureus on strawberries via the Log Reduction results, further confirmed by CLSM and SEM. • The short-lived ROS in PAW are considered the most important agents in inactivation process. • No significant change was found in color, firmness and pH of the PAW treated strawberries. - Abstract: Non-thermal plasma has been widely considered to be an effective method for decontamination of foods. Recently, numerous studies report that plasma-activated water (PAW) also has outstanding antibacterial ability. This study presents the first report on the potential of PAW for the inactivation of Staphylococcus aureus (S. aureus) inoculated on strawberries. PAW treatments achieved a reduction of S. aureus ranging from 1.6 to 2.3 log at day-0 storage, while 1.7 to 3.4 log at day-4 storage. The inactivation efficiency depended on the plasma-activated time for PAW generation and PAW-treated time of strawberries inoculated with S. aureus. LIVE/DEAD staining and scanning electron microscopy results confirm that PAW could damage the bacterial cell wall. Moreover, optical emission spectra and oxidation reduction potential results demonstrate the inactivation is mainly attributed to oxidative stress induced by reactive oxygen species in PAW. In addition, no significant change was found in color, firmness and pH of the PAW treated strawberries. Thus, PAW can be a promising alternative to traditional sanitizers applied in the fresh produce industry.

  5. An image classification approach to analyze the suppression of plant immunity by the human pathogen Salmonella Typhimurium

    Directory of Open Access Journals (Sweden)

    Schikora Marek

    2012-07-01

    Full Text Available Abstract Background The enteric pathogen Salmonella is the causative agent of the majority of food-borne bacterial poisonings. Resent research revealed that colonization of plants by Salmonella is an active infection process. Salmonella changes the metabolism and adjust the plant host by suppressing the defense mechanisms. In this report we developed an automatic algorithm to quantify the symptoms caused by Salmonella infection on Arabidopsis. Results The algorithm is designed to attribute image pixels into one of the two classes: healthy and unhealthy. The task is solved in three steps. First, we perform segmentation to divide the image into foreground and background. In the second step, a support vector machine (SVM is applied to predict the class of each pixel belonging to the foreground. And finally, we do refinement by a neighborhood-check in order to omit all falsely classified pixels from the second step. The developed algorithm was tested on infection with the non-pathogenic E. coli and the plant pathogen Pseudomonas syringae and used to study the interaction between plants and Salmonella wild type and T3SS mutants. We proved that T3SS mutants of Salmonella are unable to suppress the plant defenses. Results obtained through the automatic analyses were further verified on biochemical and transcriptome levels. Conclusion This report presents an automatic pixel-based classification method for detecting “unhealthy” regions in leaf images. The proposed method was compared to existing method and showed a higher accuracy. We used this algorithm to study the impact of the human pathogenic bacterium Salmonella Typhimurium on plants immune system. The comparison between wild type bacteria and T3SS mutants showed similarity in the infection process in animals and in plants. Plant epidemiology is only one possible application of the proposed algorithm, it can be easily extended to other detection tasks, which also rely on color information, or

  6. The European Union Summary Report on Trends and Sources of Zoonoses, Zoonotic Agents and Food-borne Outbreaks in 2011

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-04-01

    Full Text Available The European Food Safety Authority and the European Centre for Disease Prevention and Control analysed the information submitted by 27 European Union Member States on the occurrence of zoonoses and food-borne outbreaks in 2011. Campylobacteriosis was the most commonly reported zoonosis with 220,209 confirmed human cases. The occurrence of Campylobacter continued to be high in broiler meat at EU level. The decreasing trend in confirmed salmonellosis cases in humans continued with a total of 95,548 cases in 2011. Most Member States met their Salmonella reduction targets for poultry, and Salmonella is declining in these populations. In foodstuffs, Salmonella was most often detected in meat and products thereof. The number of confirmed human listeriosis cases decreased to 1,476. Listeria was seldom detected above the legal safety limit from ready-to-eat foods. A total of 9,485 confirmed verotoxigenic Escherichia coli (VTEC infections were reported. This represents an increase of 159.4 % compared with 2010 as a result of the large STEC/VTEC outbreak that occurred in 2011 in the EU, primarily in Germany. VTEC was also reported from food and animals. The number of human yersiniosis cases increased to 7,017 cases. Yersinia enterocolitica was isolated also from pig meat and pigs; 132 cases of Mycobacterium bovis and 330 cases of brucellosis in humans were also reported. The prevalence of bovine tuberculosis in cattle increased, and the prevalence of brucellosis decreased in cattle and sheep and goat populations. Trichinellosis and echinococcosis caused 268 and 781 human cases, respectively and these parasites were mainly detected in wildlife. The numbers of alveolar and of cystic echinococcosis respectively increased and decreased in the last five years. One imported human case of rabies was reported. The number of rabies cases in animals continued to decrease. Most of the 5,648 reported food-borne outbreaks were caused by Salmonella,bacterial toxins

  7. Human Babesiosis: Pathogens, Prevalence, Diagnosis and Treatment

    Science.gov (United States)

    Ord, Rosalynn Louise; Lobo, Cheryl A.

    2015-01-01

    Human babesiosis is a zoonotic disease caused by protozoan parasites of the Babesia genus, primarily in the Northeastern and Midwest United States due to B. microti, and Western Europe due to B. divergens. Parasites are transmitted by the bite of the ixodid tick when the vector takes a blood meal from the vertebrate host, and the economic importance of bovine babesiosis is well understood. The pathology of human disease is a direct result of the parasite’s ability to invade host’s red blood cells. The current understanding of human babesiosis epidemiology is that many infections remain asymptomatic, especially in younger or immune competent individuals, and the burden of severe pathology resides within older or immunocompromised individuals. However, transfusion-transmitted babesiosis is an emerging threat to public health as asymptomatic carriers donate blood and there are as yet no licensed or regulated tests to screen blood products for this pathogen. Reports of tick-borne cases within new geographical regions such as the Pacific Northwest of the US, through Eastern Europe, and into China are also on the rise. Further, new Babesia spp. have been identified globally as agents of severe human babesiosis, suggesting that the epidemiology of this disease is rapidly changing, and it is clear that human babesiosis is a serious public health concern that requires close monitoring and effective intervention measure. PMID:26594611

  8. Prevalence of Selected Food Consumption and Preparation Behaviors Associated with Increased Risks of Food-borne Disease

    National Research Council Canada - National Science Library

    Klontz, Karl C; Timbo, Babgaleh; Fein, Sara; Levy, Alan

    1995-01-01

    Although not well quantified, a portion of food-borne illnesses results from voluntary behaviors that are entirely avoidable, such as eating raw foods of animal origin or engaging in unsafe food preparation practices...

  9. Food-borne diseases associated with frozen berries consumption: a historical perspective, European Union, 1983 to 2013.

    Science.gov (United States)

    Tavoschi, L; Severi, E; Niskanen, T; Boelaert, F; Rizzi, V; Liebana, E; Gomes Dias, J; Nichols, G; Takkinen, J; Coulombier, D

    2015-07-23

    Epidemiological investigations of outbreaks of hepatitis A virus (HAV) and norovirus (NoV) infections in the European Union/European Economic Area (EU/EEA) in the last five years have highlighted frozen berries as a vehicle of infection. Given the increasing berry consumption in the EU over the last decades, we undertook a review of the existing evidence to assess the potential scale of threat associated with this product. We searched the literature and four restricted-access online platforms for outbreak/contamination events associated with consumption of frozen berries. We performed an evaluation of the sources to identify areas for improvement. The review revealed 32 independent events (i.e. outbreak, food contamination) in the period 1983–2013, of which 26 were reported after 2004. The identified pathogens were NoV, HAV and Shigella sonnei. NoV was the most common and implicated in 27 events with over 15,000 cases reported. A capture–recapture analysis was performed including three overlapping sources for the period 2005–2013. The study estimated that the event-ascertainment was 62%. Consumption of frozen berries is associated with increasing reports of NoV and HAV outbreaks and contamination events, particularly after 2003. A review of the risks associated with this product is required to inform future prevention strategies. Better integration of the available communication platforms and databases should be sought at EU/EEA level to improve monitoring, prevention and control of food-borne-related events.

  10. Human metapneumovirus: a new respiratory pathogen

    Indian Academy of Sciences (India)

    S Broor; P Bharaj; H S Chahar

    2008-11-01

    Human metapneumovirus is a recently recognized pathogen of acute respiratory tract infection (ARI) in children as well as elderly and immunocompromised adults. The virus belongs to the family Paramyxoviridae, sub family Pneumovirinae and genus Metapneumovirus. Through genetic analysis it has been characterized into two groups A and B which are further divided into four sub-lineages. The virus is difficult to grow in tissue culture and hence reverse transcriptase-polymerase chain reaction (RT-PCR) for N and L gene is the method of choice for diagnosis. The virus has been seen in all countries with seasonal distribution in winter months for temperate and spring/summer for tropical countries. F gene is the most conserved among different lineages and efforts are underway to design recombination vaccine using F gene.

  11. Diagnostic real-time PCR assays for the detection of emetic Bacillus cereus strains in foods and recent food-borne outbreaks.

    Science.gov (United States)

    Fricker, Martina; Messelhäusser, Ute; Busch, Ulrich; Scherer, Siegfried; Ehling-Schulz, Monika

    2007-03-01

    Cereulide-producing Bacillus cereus can cause an emetic type of food-borne disease that mimics the symptoms provoked by Staphylococcus aureus. Based on the recently discovered genetic background for cereulide formation, a novel 5' nuclease (TaqMan) real-time PCR assay was developed to provide a rapid and sensitive method for the specific detection of emetic B. cereus in food. The TaqMan assay includes an internal amplification control and primers and a probe designed to target a highly specific part of the cereulide synthetase genes. Additionally, a specific SYBR green I assay was developed and extended to create a duplex SYBR green I assay for the one-step identification and discrimination of the two emesis-causing food pathogens B. cereus and S. aureus. The inclusivity and exclusivity of the assay were assessed using a panel of 100 strains, including 23 emetic B. cereus and 14 S. aureus strains. Different methods for DNA isolation from artificially contaminated foods were evaluated, and established real-time assays were used to analyze two recent emetic food poisonings in southern Germany. One of the food-borne outbreaks included 17 children visiting a day care center who vomited after consuming a reheated rice dish, collapsed, and were hospitalized; the other case concerned a single food-poisoning incident occurring after consumption of cauliflower. Within 2 h, the etiological agent of these food poisonings was identified as emetic B. cereus by using the real-time PCR assay.

  12. Scientific Opinion on the evaluation of molecular typing methods for major food-borne microbiological hazards and their use for attribution modelling, outbreak investigation and scanning surveillance: Part 1 (evaluation of methods and applications

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Biological Hazards (BIOHAZ

    2013-12-01

    Full Text Available An evaluation of molecular typing methods that can be applied to the food-borne pathogens Salmonella, Campylobacter, Shiga toxin-producing Escherichia coli and Listeria monocytogenes is presented. This evaluation is divided in two parts. Firstly, commonly used molecular typing methods are assessed against a set of predefined criteria relating to discriminatory capacity, reproducibility, repeatability and current or potential suitability for international harmonisation. Secondly, the methods are evaluated for their appropriateness for use in different public health-related applications. These applications include outbreak detection and investigation, attribution modelling, the potential for early identification of food-borne strains with epidemic potential and the integration of the resulting data in risk assessment. The results of these evaluations provide updated insights into the use and potential for use of molecular characterisation methods, including whole genome sequencing technologies, in microbial food safety. Recommendations are also made in order to encourage a holistic and structured approach to the use of molecular characterisation methods for food-borne pathogens; in particular, on the importance of structured co-ordination at international level to help overcome current limitations in harmonisation of data analysis and interpretation.

  13. Point of care nucleic acid detection of viable pathogenic bacteria with isothermal RNA amplification based paper biosensor

    Science.gov (United States)

    Liu, Hongxing; Xing, Da; Zhou, Xiaoming

    2014-09-01

    Food-borne pathogens such as Listeria monocytogenes have been recognized as a major cause of human infections worldwide, leading to substantial health problems. Food-borne pathogen identification needs to be simpler, cheaper and more reliable than the current traditional methods. Here, we have constructed a low-cost paper biosensor for the detection of viable pathogenic bacteria with the naked eye. In this study, an effective isothermal amplification method was used to amplify the hlyA mRNA gene, a specific RNA marker in Listeria monocytogenes. The amplification products were applied to the paper biosensor to perform a visual test, in which endpoint detection was performed using sandwich hybridization assays. When the RNA products migrated along the paper biosensor by capillary action, the gold nanoparticles accumulated at the designated Test line and Control line. Under optimized experimental conditions, as little as 0.5 pg/μL genomic RNA from Listeria monocytogenes could be detected. The whole assay process, including RNA extraction, amplification, and visualization, can be completed within several hours. The developed method is suitable for point-of-care applications to detect food-borne pathogens, as it can effectively overcome the false-positive results caused by amplifying nonviable Listeria monocytogenes.

  14. Bovine cysticercosis and human taeniosis in South-west Shoa zone ...

    African Journals Online (AJOL)

    undertaken to assess the status of taeniosis and associated risk factors in human in these towns. ... It is well documented that a number of food born parasitic infections prevail worldwide. Among ..... Emerging food-born parasites. Vet. Parasitol.

  15. Genetic diversity among food-borne and waterborne norovirus strains causing outbreaks in Sweden.

    Science.gov (United States)

    Lysén, Maria; Thorhagen, Margareta; Brytting, Maria; Hjertqvist, Marika; Andersson, Yvonne; Hedlund, Kjell-Olof

    2009-08-01

    A total of 101 food-borne and waterborne outbreaks that were caused by norovirus and that resulted in more than 4,100 cases of illness were reported to the Swedish Institute for Infectious Disease Control from January 2002 to December 2006. Sequence and epidemiological data for isolates from 73 outbreaks were analyzed. In contrast to health care-related outbreaks, no clear seasonality could be observed. Sequence analysis showed a high degree of genetic variation among the noroviruses detected. Genogroup II (GII) viruses were detected in 70% of the outbreaks, and of those strains, strains of GII.4 were the most prevalent and were detected in 25% of all outbreaks. The GII.4 variants detected in global outbreaks in health care settings during 2002, 2004, and 2006 were also found in the food-borne outbreaks. GI strains totally dominated as the cause of water-related (drinking and recreational water) outbreaks and were found in 12 of 13 outbreaks. In 14 outbreaks, there were discrepancies among the polymerase and capsid genotype results. In four outbreaks, the polymerase of the recombinant GII.b virus occurred together with the GII.1 or GII.3 capsids, while the GII.7 polymerase occurred together with the GII.6 and GII.7 capsids. Mixed infections were observed in six outbreaks; four of these were due to contaminated water, and two were due to imported frozen berries. Contaminated food and water serve as important reservoirs for noroviruses. The high degree of genetic diversity found among norovirus strains causing food-borne and waterborne infections stresses the importance of the use of broad reaction detection methods when such outbreaks are investigated.

  16. EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards) , 2013 . Scientific Opinion on the evaluation of molecular typing methods for major food-borne microbiological hazards and their use for attribution modelling, outbreak investigation and scanning surveillance: Part 1 (evaluation of methods and applications)

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    An evaluation of molecular typing methods that can be applied to the food-borne pathogens Salmonella, Campylobacter, Shiga toxin-producing Escherichia coli and Listeria monocytogenes is presented. This evaluation is divided in two parts. Firstly, commonly used molecular typing methods are assesse...

  17. Pathogens and host immunity in the ancient human oral cavity

    DEFF Research Database (Denmark)

    Warinner, Christina; Rodrigues, João F Matias; Vyas, Rounak

    2014-01-01

    cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction...... of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing confirmation of a long-term association between host immune factors, 'red complex' pathogens and periodontal disease, and (vi) DNA sequences matching dietary sources. Directly datable and nearly ubiquitous, dental...... calculus permits the simultaneous investigation of pathogen activity, host immunity and diet, thereby extending direct investigation of common diseases into the human evolutionary past....

  18. Evolution of Bacterial Pathogens within the Human Host

    OpenAIRE

    Bliven, Kimberly A.; Maurelli, Anthony T.

    2016-01-01

    Selective pressures within the human host, including interactions with innate and adaptive immune responses, exposure to medical interventions such as antibiotics, and competition with commensal microbiota all facilitate the evolution of bacterial pathogens. In this chapter, we present examples of pathogen strategies which emerged as a result of selective pressures within the human host niche, and discuss the resulting co-evolutionary ‘arms race’ between these organisms. In bacterial pathogen...

  19. Campylobacter jejuni : A brief overview on pathogenicity-associated factors and disease-mediating mechanisms

    NARCIS (Netherlands)

    Dasti, Javid I.; Tareen, A. Malik; Lugert, Raimond; Zautner, Andreas E.; Gross, Uwe

    Campylobacter jejuni has long been recognized as a cause of bacterial food-borne illness, and surprisingly, it remains the most prevalent bacterial food-borne pathogen in the industrial world to date. Natural reservoirs for this Gram-negative, spiral-shaped bacterium are wild birds, whose intestines

  20. Campylobacter jejuni : A brief overview on pathogenicity-associated factors and disease-mediating mechanisms

    NARCIS (Netherlands)

    Dasti, Javid I.; Tareen, A. Malik; Lugert, Raimond; Zautner, Andreas E.; Gross, Uwe

    2010-01-01

    Campylobacter jejuni has long been recognized as a cause of bacterial food-borne illness, and surprisingly, it remains the most prevalent bacterial food-borne pathogen in the industrial world to date. Natural reservoirs for this Gram-negative, spiral-shaped bacterium are wild birds, whose intestines

  1. Bioprotective properties of seaweeds: In vitro evaluation of antioxidant activity and antimicrobial activity against food borne bacteria in relation to polyphenolic content

    Directory of Open Access Journals (Sweden)

    Kesika Periyanaina

    2008-07-01

    Full Text Available Abstract Background For many years chemical preservatives have been used in food, to act as either antimicrobials or antioxidants or both. In general, consumers regard additive-free foods as safer since preservatives can cause health hazards like asthma and cancer and are suspected to be mutagenic and neurotoxic. The present study was carried out to evaluate the antimicrobial and antioxidant activity of methanolic extracts of seaweeds, with a view to developing safer food preservatives. Methods Ten edible seaweeds, which have wide pharmaceutical application, were collected from Central Marine Fisheries Research Institute, Tamil Nadu, India and evaluated for antioxidant and antimicrobial activity against food borne pathogens. Results The results indicate that Gelidiella acerosa has the highest antioxidant activity while Haligra sps exhibited antibacterial activity against Staphylococcus aureus (MTCC 96. Conclusion Quantitative analysis of the total phenolic content of the seaweeds indicated that Gelidella acerosa and Haligra sps have high phenolic contents, which correlated to their respective antioxidant and antimicrobial activity

  2. Bioprotective properties of seaweeds: in vitro evaluation of antioxidant activity and antimicrobial activity against food borne bacteria in relation to polyphenolic content.

    Science.gov (United States)

    Devi, Kasi Pandima; Suganthy, Natarajan; Kesika, Periyanaina; Pandian, Shanmugaiahthevar Karutha

    2008-07-10

    For many years chemical preservatives have been used in food, to act as either antimicrobials or antioxidants or both. In general, consumers regard additive-free foods as safer since preservatives can cause health hazards like asthma and cancer and are suspected to be mutagenic and neurotoxic. The present study was carried out to evaluate the antimicrobial and antioxidant activity of methanolic extracts of seaweeds, with a view to developing safer food preservatives. Ten edible seaweeds, which have wide pharmaceutical application, were collected from Central Marine Fisheries Research Institute, Tamil Nadu, India and evaluated for antioxidant and antimicrobial activity against food borne pathogens. The results indicate that Gelidiella acerosa has the highest antioxidant activity while Haligra sps exhibited antibacterial activity against Staphylococcus aureus (MTCC 96). Quantitative analysis of the total phenolic content of the seaweeds indicated that Gelidella acerosa and Haligra sps have high phenolic contents, which correlated to their respective antioxidant and antimicrobial activity.

  3. Evolution of Bacterial Pathogens Within the Human Host.

    Science.gov (United States)

    Bliven, Kimberly A; Maurelli, Anthony T

    2016-02-01

    Selective pressures within the human host, including interactions with innate and adaptive immune responses, exposure to medical interventions such as antibiotics, and competition with commensal microbiota all facilitate the evolution of bacterial pathogens. In this chapter, we present examples of pathogen strategies that emerged as a result of selective pressures within the human host niche and discuss the resulting coevolutionary "arms race" between these organisms. In bacterial pathogens, many of the genes responsible for these strategies are encoded on mobile pathogenicity islands or plasmids, underscoring the importance of horizontal gene transfer in the emergence of virulent microbial species.

  4. Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis

    OpenAIRE

    Desjardins, Christopher A; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailao, Alexandre M.; Brigido, Marcelo de Macedo; Silva Ferreira, Marcia Eliana da; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; Leon-Narvaez, Henry

    2011-01-01

    Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasi...

  5. Hygienic Practice and Knowledge of food borne diseases in Home Kitchen Handlers

    Directory of Open Access Journals (Sweden)

    Ashfaq Modiwala, Rajshekhar R Wavare

    2015-01-01

    Full Text Available Background: Food borne illness cases may occur due to improperly prepared or mishandled food, unhygienic sanitation and cleaning practice at home by home kitchen handlers. Objective: To explore the knowledge and practice of literate female of Indore city who are dealing with Home kitchen every day. Methodology: A Cross-Sectional study among 160 participants according to their profession (Health sector workers, Non-health sector workers, House Makers and Students were selected randomly and interviewed using self administered questionnaire. Result: It shows that the mean percentage score for the good knowledge and hygienic practice was 79.44% and 71.15%. Knowledge practice scores was significantly (p < 0.0006 different by the levels of education and for Hygienic practice a significant difference (p <0.05 was observed between Health and Non-Health sector worker. Conclusion: Knowledge and Practice among kitchen handlers was significantly (p= 0.0202 higher in Health sector workers than other sectors.

  6. Cerium oxide-chitosan based nanobiocomposite for food borne mycotoxin detection

    Science.gov (United States)

    Kaushik, Ajeet; Solanki, Pratima R.; Pandey, M. K.; Ahmad, Sharif; Malhotra, Bansi D.

    2009-10-01

    Cerium oxide nanoparticles (NanoCeO2) and chitosan (CH) based nanobiocomposite film deposited onto indium-tin-oxide coated glass substrate has been used to coimmobilize rabbit immunoglobin (r-IgGs) and bovine serum albumin (BSA) for food borne mycotoxin [ochratoxin-A (OTA)] detection. Electrochemical studies reveal that presence of NanoCeO2 increases effective electro-active surface area of CH-NanoCeO2/indium tin oxide (ITO) nanobiocomposite resulting in high loading of r-IgGs. BSA/r-IgGs/CH-NanoCeO2/ITO immunoelectrode exhibits improved linearity (0.25-6.0 ng/dl), detection limit (0.25 ng/dl), response time (25 s), sensitivity (18 μA/ng dl-1 cm-2), and regression coefficient (r2˜0.997).

  7. Determination of histamine in milkfish stick implicated in food-borne poisoning

    Directory of Open Access Journals (Sweden)

    Yi-Chen Lee

    2016-01-01

    Full Text Available An incident of food-borne poisoning causing illness in 37 victims due to ingestion of fried fish sticks occurred in September 2014, in Tainan city, southern Taiwan. Leftovers of the victims' fried fish sticks and 16 other raw fish stick samples from retail stores were collected and tested to determine the occurrence of histamine and histamine-forming bacteria. Two suspected fried fish samples contained 86.6 mg/100 g and 235.0 mg/100 g histamine; levels that are greater than the potential hazard action level (50 mg/100 g in most illness cases. Given the allergy-like symptoms of the victims and the high histamine content in the suspected fried fish samples, this food-borne poisoning was strongly suspected to be caused by histamine intoxication. Moreover, the fish species of suspected samples was identified as milkfish (Chanos chanos, using polymerase chain reaction direct sequence analysis. In addition, four of the 16 commercial raw milkfish stick samples (25% had histamine levels greater than the US Food & Drug Administration guideline of 5.0 mg/100 g for scombroid fish and/or products. Ten histamine-producing bacterial strains, capable of producing 373–1261 ppm of histamine in trypticase soy broth supplemented with 1.0% L-histidine, were identified as Enterobacter aerogenes (4 strains, Enterobacter cloacae (1 strain, Morganella morganii (2 strains, Serratia marcescens (1 strain, Hafnia alvei (1 strain, and Raoultella orithinolytica (1 strain, by 16S ribosomal DNA sequencing with polymerase chain reaction amplification.

  8. Antibacterial activity of mangrove leaf extracts against human pathogens

    Digital Repository Service at National Institute of Oceanography (India)

    Sahoo, G.; Mulla, N.S.S.; Ansari, Z.A.; Mohandass, C.

    The antibacterial activity of leaf extract of mangroves, namely, Rhizophora mucronata, Sonneratia alba and Exoecaria agallocha from Chorao island, Goa was investigated against human bacterial pathogens Staphylococcus aureus, Streptococcus sp...

  9. Listeria monocytogenes infection in poultry and its public health importance with special reference to food borne zoonoses.

    Science.gov (United States)

    Dhama, Kuldeep; Verma, Amit Kumar; Rajagunalan, S; Kumar, Amit; Tiwari, Ruchi; Chakraborty, Sandip; Kumar, Rajesh

    2013-04-01

    Listeriosis is a disease that causes septicemia or encephalitis in humans, animals and birds. Although, the disease is rare and sporadic in poultry but if occurs then causes septicemia or sometimes localized encephalitis. Occasionally, the disease is seen in young chicks and the causative agent, like in humans and animals, is Listeria monocytogenes. The organism is capable to infect almost all animals and poultry; however, outbreaks of listeriosis are infrequent in birds. It is widely distributed among avian species and chickens, turkeys, waterfowl (geese, ducks), game birds, pigeons, parrots, wood grouse, snowy owl, eagle, canaries, which appear to be the most commonly affected. Chickens are thought to be the carriers of Listeria and also the prime reservoirs for the infection and thus contaminate the litter and environment of the poultry production units. Listeriosis is often noticed along with other poultry diseases such as coccidiosis, infectious coryza, salmonellosis, campylobacteriosis and parasitic infections, signifying the opportunistic nature of the organism. Intestinal colonization of poultry and the presence of L. monocytogenes in feces represent a potential source of the organism for listeriosis in ruminants. Man gets infection from raw broiler meat due to Listeria contamination and unhygienic conditions of the processing area, rather than acquiring direct infection from birds. With the changing food habits of the people, the health consciousness is also increasing and since listeriosis has now been recognized as an emerging food borne zoonoses. Therefore, this review has been compiled to make aware the poultry producers and the consumers of poultry meat/products regarding the importance of the disease and its public health significance.

  10. Analysis of an Epidemiological Survey of Food Borne Disease%一起食源性疾病的流行病与调查结果分析

    Institute of Scientific and Technical Information of China (English)

    王勇

    2016-01-01

    目的:在食源性疾病(亚硝酸盐中毒)的调查、处置、准确判定,需要实验室提供科学、准确的数据支持。方法对食物中毒事件中可疑食品、调料、生物样本(呕吐物、排泄物)等进行实验室检验,与亚硝酸盐的中毒量、致病(死)量比较判定。结果实验室检验结果的准确,能快速、准确为流行病调查结果提供依据,并认定亚硝酸盐中毒。结论判定食源性疾病(亚硝酸盐中毒)离不开实验室科学、准确的检验数据。%Objective The investigation, disposal and accurate determination of food borne disease (nitrite poisoning) need the support of laboratory to provide scientific and accurate data. Methods The suspicious food, condiment, biological sam-ples (vomit, feces) were tested in laboratory, and the amount of nitrite poisoning and pathogenic and lethal amount were compared and determined. Results Laboratory test results are accurate, which can quickly and accurately provide the basis for epidemiological survey results, and identify nitrite poisoning. Conclusion Determination of food borne disease (nitrite poisoning) can not be separated from laboratory science and accurate test data.

  11. Pathogenic Vibrio parahaemolyticus isolated from biofouling on commercial vessels and harbor structures.

    Science.gov (United States)

    Revilla-Castellanos, Valeria J; Guerrero, Abraham; Gomez-Gil, Bruno; Navarro-Barrón, Erick; Lizárraga-Partida, Marcial L

    2015-01-01

    Ballast water is a significant vector of microbial dissemination; however, biofouling on commercial vessel hulls has been poorly studied with regard to pathogenic bacteria transport. Biofouling on three commercial vessels and seven port structures in Ensenada, Baja California, Mexico, was examined by qPCR to identify and quantify Vibrio parahaemolyticus, a worldwide recognized food-borne human pathogen. Pathogenic variants (trh+, tdh+) of V. parahaemolyticus were detected in biofouling homogenates samples from several docks in Ensenada and on the hulls of ships with Japanese and South Korean homeports, but not in reference sampling stations. A total of 26 tdh+ V. parahaemolyticus colonies and 1 ORF8+/O3:K6 strain were also isolated from enriched biofouling homogenate samples confirming the qPCR analysis. Our results suggest that biofouling is an important reservoir of pathogenic vibrios. Thus, ship biofouling might be an overlooked vector with regard to the dissemination of pathogens, primarily pathogenic V. parahaemolyticus.

  12. Corynebacterium ulcerans, an emerging human pathogen.

    Science.gov (United States)

    Hacker, Elena; Antunes, Camila A; Mattos-Guaraldi, Ana L; Burkovski, Andreas; Tauch, Andreas

    2016-09-01

    While formerly known infections of Corynebacterium ulcerans are rare and mainly associated with contact to infected cattle, C. ulcerans has become an emerging pathogen today. In Western Europe, cases of respiratory diphtheria caused by C. ulcerans have been reported more often than infections by Corynebacterium diphtheria, while systemic infections are also increasingly reported. Little is known about factors that contribute to host colonization and virulence of this zoonotic pathogen. Research in this field has received new impetus by the publication of several C. ulcerans genome sequences in the past years. This review gives a comprehensive overview of the basic knowledge of C. ulcerans, as well as the recent advances made in the analysis of putative virulence factors.

  13. Comparison of three Listeria monocytogenes strains in a guinea-pig model simulating food-borne exposure

    DEFF Research Database (Denmark)

    Roldgaard, Bent; Andersen, Jens Bo; Hansen, Tina Beck

    2009-01-01

    Three different Listeria monocytogenes strains, LO28 (a laboratory strain with truncated InlA), 4446 (a clinical isolate) and 7291 (a food isolate), were compared in a guinea-pig model designed to mimic food-borne exposure. The objectives were (1) to verify the applicability of the animal model f...

  14. Dry mouth as an initial sign of food-borne botulism: a case report and review of the literature.

    Science.gov (United States)

    Manfredi, Maddalena; Scoditti, Umberto; Angelini, Monica; de Giampaulis, Piero; Borrini, Bianca Maria; Macaluso, Guido Maria; Pavesi, Giovanni; Vescovi, Paolo

    2011-04-01

    Botulism is a rare neuroparalytic disease caused by a potent neurotoxin produced by Clostridium botulinum. There are different clinical types of botulism. Early diagnosis of the condition is essential for effective treatment. We report a case of food-borne botulism in identical twins characterized by severe initial oral involvement and a review of the literature about the condition.

  15. Validation of a PCR-based method for detection of food-borne thermotolerant Campylobacters in a multicenter collaborative trial

    DEFF Research Database (Denmark)

    Josefsen, Mathilde Hartmann; Cook, N.; D'Agostino, M.;

    2004-01-01

    A PCR-based method for rapid detection of food-borne thermotolerant campylobacters was evaluated through a collaborative trial with 12 laboratories testing spiked carcass rinse samples. The method showed an interlaboratory diagnostic sensitivity of 96.7% and a diagnostic specificity of 100% for c...

  16. Pathogens and host immunity in the ancient human oral cavity.

    Science.gov (United States)

    Warinner, Christina; Rodrigues, João F Matias; Vyas, Rounak; Trachsel, Christian; Shved, Natallia; Grossmann, Jonas; Radini, Anita; Hancock, Y; Tito, Raul Y; Fiddyment, Sarah; Speller, Camilla; Hendy, Jessica; Charlton, Sophy; Luder, Hans Ulrich; Salazar-García, Domingo C; Eppler, Elisabeth; Seiler, Roger; Hansen, Lars H; Castruita, José Alfredo Samaniego; Barkow-Oesterreicher, Simon; Teoh, Kai Yik; Kelstrup, Christian D; Olsen, Jesper V; Nanni, Paolo; Kawai, Toshihisa; Willerslev, Eske; von Mering, Christian; Lewis, Cecil M; Collins, Matthew J; Gilbert, M Thomas P; Rühli, Frank; Cappellini, Enrico

    2014-04-01

    Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first, to our knowledge, high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing confirmation of a long-term association between host immune factors, 'red complex' pathogens and periodontal disease, and (vi) DNA sequences matching dietary sources. Directly datable and nearly ubiquitous, dental calculus permits the simultaneous investigation of pathogen activity, host immunity and diet, thereby extending direct investigation of common diseases into the human evolutionary past.

  17. Mice with human immune system components as in vivo models for infections with human pathogens

    OpenAIRE

    Rämer, P C; Chijioke, O; Meixlsperger, S; Leung, C S; Münz, C.

    2011-01-01

    Many pathogens relevant to human disease do not infect other animal species. Therefore, animal models that reconstitute or harbour human tissues are explored as hosts for these. In this review, we will summarize recent advances to utilize mice with human immune system components, reconstituted from hematopoietic progenitor cells in vivo. Such mice can be used to study human pathogens that replicate in leucocytes. In addition to studying the replication of these pathogens, the reconstituted hu...

  18. A protein microarray for the rapid screening of patients suspected of infection with various food-borne helminthiases.

    Directory of Open Access Journals (Sweden)

    Jia-Xu Chen

    Full Text Available BACKGROUND: Food-borne helminthiases (FBHs have become increasingly important due to frequent occurrence and worldwide distribution. There is increasing demand for developing more sensitive, high-throughput techniques for the simultaneous detection of multiple parasitic diseases due to limitations in differential clinical diagnosis of FBHs with similar symptoms. These infections are difficult to diagnose correctly by conventional diagnostic approaches including serological approaches. METHODOLOGY/PRINCIPAL FINDINGS: In this study, antigens obtained from 5 parasite species, namely Cysticercus cellulosae, Angiostrongylus cantonensis, Paragonimus westermani, Trichinella spiralis and Spirometra sp., were semi-purified after immunoblotting. Sera from 365 human cases of helminthiasis and 80 healthy individuals were assayed with semi-purified antigens by both a protein microarray and the enzyme-linked immunosorbent assay (ELISA. The sensitivity, specificity and simplicity of each test for the end-user were evaluated. The specificity of the tests ranged from 97.0% (95% confidence interval (CI: 95.3-98.7% to 100.0% (95% CI: 100.0% in the protein microarray and from 97.7% (95% CI: 96.2-99.2% to 100.0% (95% CI: 100.0% in ELISA. The sensitivity varied from 85.7% (95% CI: 75.1-96.3% to 92.1% (95% CI: 83.5-100.0% in the protein microarray, while the corresponding values for ELISA were 82.0% (95% CI: 71.4-92.6% to 92.1% (95% CI: 83.5-100.0%. Furthermore, the Youden index spanned from 0.83 to 0.92 in the protein microarray and from 0.80 to 0.92 in ELISA. For each parasite, the Youden index from the protein microarray was often slightly higher than the one from ELISA even though the same antigen was used. CONCLUSIONS/SIGNIFICANCE: The protein microarray platform is a convenient, versatile, high-throughput method that can easily be adapted to massive FBH screening.

  19. [THE IDENTIFICATION AND DIFFERENTIATION OF BACTERIOPHAGES OF HUMAN PATHOGENIC VIBRIO].

    Science.gov (United States)

    Gaevskaia, N E; Kudriakova, T A; Makedonova, L D; Kachkina, G V

    2015-04-01

    The issue of identification and differentiation of large group of bacteriophages of human pathogenic vibrio is still unresolved. In research and practical applied purposes it is important to consider characteristics of bacteriophages for establishing similarity and differences between them. The actual study was carried out to analyze specimens of DNA-containing bacteriophages of pathogenic vibrio. The overwhelming majority of them characterized by complicated type of symmetry--phages with double-helical DNA and also phages with mono-helical DNA structure discovered recently in vibrio. For the first time, the general framework of identification and differentiation of bacteriophages of pathogenic vibrio was developed. This achievement increases possibility to establish species assignment of phages and to compare with phages registered in the database. "The collection of bacteriophages and test-strains of human pathogenic vibrio" (No2010620549 of 24.09.210).

  20. The role of extraintestinal foodborne pathogens in human illness

    Science.gov (United States)

    In recent years understanding the role of foodborne pathogens in human disease has evolved to include conditions outside the gastrointestinal diseases typically associated with bacteria such as Salmonella, Shiga toxin-producing Escherichia coli (STEC), Listeria monocytogenes, etc. Other human pathog...

  1. Self-assembled monolayer based impedimetric platform for food borne mycotoxin detection

    Science.gov (United States)

    Solanki, Pratima Rathee; Kaushik, Ajeet; Manaka, T.; Pandey, Manoj Kumar; Iwamoto, M.; Agrawal, Ved Varun; Malhotra, Bansi Dhar

    2010-12-01

    A self-assembled monolayer (SAM) of 11-amino-1-undecanethiol (AUT) has been fabricated onto a gold (Au) substrate to co-immobilize anti-ochratoxin-A antibodies (AO-IgGs) and bovine serum albumin (BSA) to detect food borne mycotoxin [i.e., ochratoxin-A (OTA)]. AUT/Auelectrode, AO-IgGs/AUT/Au immunoelectrode and BSA/IgGs/AUT/Au immunoelectrode have been characterized using scanning electron microscopy (SEM) and electrochemical studies such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Electrochemical studies reveal that the AUT-SAM with NH2groups provide favorable conditions to immobilize AO-IgGs with better orientation, resulting in enhanced electron transport to obtain improved sensing characteristics. The EIS response studies of the BSA/AO-IgGs/AUT/Au immunoelectrode obtained as a function of OTA concentration reveal that the value of the charge transfer resistance (RCT) increases with increased OTA concentration. The BSA/AO-IgGs/AUT/Au immunoelectrode exhibits linearity over 0.5-6.0 ng/dl, detection limit of 0.08 ng/dl using 3σb/m criteria, response time of 30 s and sensitivity of ~36.83 Ω/ng dl-1 cm-2 with a regression coefficient of 0.999. Attempts have been made to monitor the change in RCT of BSA/AO-IgGs/AUT/Au immunoelectrode on addition of coffee samples.

  2. Pathogenicity of human high pathogenic H5N1 virus with different plaque property

    Directory of Open Access Journals (Sweden)

    Yong-qiang LI

    2011-06-01

    Full Text Available Objective To determine the pathogenicity of human high pathogenic H5N1 virus with different plaque property,and provide a new train of thought and basis for research on crossing species-genus transmission of avian influenza virus.Methods Variants with different plaque property(larger-and smaller-plaque variant were isolated from A/Beijing/01/03(H5N1(BJ01 by the plaque purification.Mice were inoculated intranasally(i.n. with each kind of isolated variant and monitored for 14 days to record and calculate the body weight change and the survival rate.The difference in pathogenicity of isolated variants was estimated with proper principle of statistics.Results The plaques of original strain of BJ01 virus were heterogeneous with various size and shape.Larger-plaque variants(L1 and L2 and smaller-plaque variants(S1,S2 and S3 were isolated separately.The pathogenicity was higher in S1 and S2 variants than in S3,L1 and L2 variants,and that of L2 variant was the lowest.Variants forming different plaques were heterogeneous in pathogenicity,and those forming same plaques were also heterogeneous in pathogenicity.Conclusion There is no linear correlation between the pathogenicity of variants and the size of plaque they formed.The variants with different pathogenicity could be isolated from the same H5N1 virus strain by plaque purification.These results would provide a basis for vaccine development and the studies on molecular mechanism of H5N1 virus.

  3. Bacillus cereus, a volatile human pathogen.

    Science.gov (United States)

    Bottone, Edward J

    2010-04-01

    Bacillus cereus is a Gram-positive aerobic or facultatively anaerobic, motile, spore-forming, rod-shaped bacterium that is widely distributed environmentally. While B. cereus is associated mainly with food poisoning, it is being increasingly reported to be a cause of serious and potentially fatal non-gastrointestinal-tract infections. The pathogenicity of B. cereus, whether intestinal or nonintestinal, is intimately associated with the production of tissue-destructive exoenzymes. Among these secreted toxins are four hemolysins, three distinct phospholipases, an emesis-inducing toxin, and proteases. The major hurdle in evaluating B. cereus when isolated from a clinical specimen is overcoming its stigma as an insignificant contaminant. Outside its notoriety in association with food poisoning and severe eye infections, this bacterium has been incriminated in a multitude of other clinical conditions such as anthrax-like progressive pneumonia, fulminant sepsis, and devastating central nervous system infections, particularly in immunosuppressed individuals, intravenous drug abusers, and neonates. Its role in nosocomial acquired bacteremia and wound infections in postsurgical patients has also been well defined, especially when intravascular devices such as catheters are inserted. Primary cutaneous infections mimicking clostridial gas gangrene induced subsequent to trauma have also been well documented. B. cereus produces a potent beta-lactamase conferring marked resistance to beta-lactam antibiotics. Antimicrobials noted to be effective in the empirical management of a B. cereus infection while awaiting antimicrobial susceptibility results for the isolate include ciprofloxacin and vancomycin.

  4. Equivalent T cell epitope promiscuity in ecologically diverse human pathogens.

    Science.gov (United States)

    Wiens, Kirsten E; Swaminathan, Harish; Copin, Richard; Lun, Desmond S; Ernst, Joel D

    2013-01-01

    The HLA (human leukocyte antigen) molecules that present pathogen-derived epitopes to T cells are highly diverse. Correspondingly, many pathogens such as HIV evolve epitope variants in order to evade immune recognition. In contrast, another persistent human pathogen, Mycobacterium tuberculosis, has highly conserved epitope sequences. This raises the question whether there is also a difference in the ability of these pathogens' epitopes to bind diverse HLA alleles, referred to as an epitope's binding promiscuity. To address this question, we compared the in silico HLA binding promiscuity of T cell epitopes from pathogens with distinct infection strategies and outcomes of human exposure. We used computer algorithms to predict the binding affinity of experimentally-verified microbial epitope peptides to diverse HLA-DR, HLA-A and HLA-B alleles. We then analyzed binding promiscuity of epitopes derived from HIV and M. tuberculosis. We also analyzed promiscuity of epitopes from Streptococcus pyogenes, which is known to exhibit epitope diversity, and epitopes of Bacillus anthracis and Clostridium tetani toxins, as these bacteria do not depend on human hosts for their survival or replication, and their toxin antigens are highly immunogenic human vaccines. We found that B. anthracis and C. tetani epitopes were the most promiscuous of the group that we analyzed. However, there was no consistent difference or trend in promiscuity in epitopes contained in HIV, M. tuberculosis, and S. pyogenes. Our results show that human pathogens with distinct immune evasion strategies and epitope diversities exhibit equivalent levels of T cell epitope promiscuity. These results indicate that differences in epitope promiscuity do not account for the observed differences in epitope variation and conservation.

  5. Equivalent T cell epitope promiscuity in ecologically diverse human pathogens.

    Directory of Open Access Journals (Sweden)

    Kirsten E Wiens

    Full Text Available BACKGROUND: The HLA (human leukocyte antigen molecules that present pathogen-derived epitopes to T cells are highly diverse. Correspondingly, many pathogens such as HIV evolve epitope variants in order to evade immune recognition. In contrast, another persistent human pathogen, Mycobacterium tuberculosis, has highly conserved epitope sequences. This raises the question whether there is also a difference in the ability of these pathogens' epitopes to bind diverse HLA alleles, referred to as an epitope's binding promiscuity. To address this question, we compared the in silico HLA binding promiscuity of T cell epitopes from pathogens with distinct infection strategies and outcomes of human exposure. METHODS: We used computer algorithms to predict the binding affinity of experimentally-verified microbial epitope peptides to diverse HLA-DR, HLA-A and HLA-B alleles. We then analyzed binding promiscuity of epitopes derived from HIV and M. tuberculosis. We also analyzed promiscuity of epitopes from Streptococcus pyogenes, which is known to exhibit epitope diversity, and epitopes of Bacillus anthracis and Clostridium tetani toxins, as these bacteria do not depend on human hosts for their survival or replication, and their toxin antigens are highly immunogenic human vaccines. RESULTS: We found that B. anthracis and C. tetani epitopes were the most promiscuous of the group that we analyzed. However, there was no consistent difference or trend in promiscuity in epitopes contained in HIV, M. tuberculosis, and S. pyogenes. CONCLUSIONS: Our results show that human pathogens with distinct immune evasion strategies and epitope diversities exhibit equivalent levels of T cell epitope promiscuity. These results indicate that differences in epitope promiscuity do not account for the observed differences in epitope variation and conservation.

  6. YERSINIA ENTEROCOLITICA: AN IMPORTANT HUMAN FOODBORNE PATHOGEN

    Science.gov (United States)

    Yersinia enterocolitica is a Gram-negative microbe of public health importance and is under national FoodNet surveillance in the United States. The majority of human yersiniosis cases are foodborne. Consumption of dairy products (milk, ice cream), water, vegetables (tofu), and pork have been linke...

  7. Evidence of a species complex within the food-borne trematode Opisthorchis viverrini and possible co-evolution with their first intermediate hosts.

    Science.gov (United States)

    Saijuntha, Weerachai; Sithithaworn, Paiboon; Wongkham, Sopit; Laha, Thewarach; Pipitgool, Vichit; Tesana, Smarn; Chilton, Neil B; Petney, Trevor N; Andrews, Ross H

    2007-05-01

    The food-borne trematodes, Opisthorchis viverrini, O. felineus and Clonorchis sinensis, have long been recognized as the cause of major human health problems, with an estimated 40 million infected persons. Of the three species of liver fluke, only O. viverrini is classified as a type 1 carcinogen because of its role as an initiator of chronic inflammation and the subsequent development of cholangiocarcinoma. At present, there are no techniques for the early diagnosis of cholangiocarcinoma and it is fatal for most patients. There is considerable variation in parasite prevalence and disease presentation in different geographical areas, the latter of which may be associated with genetic differences among parasites. In the present study, multilocus enzyme electrophoresis was used to provide a comprehensive genetic characterization of O. viverrini from different geographical localities in Thailand and the Peoples' Democratic Republic of Laos. Parasites from different localities were compared genetically at 32 enzyme loci. The results of the genetic analyses are sufficient to reject the null hypothesis that O. viverrini represents a single species. Therefore, O. viverrini consists of at least two genetically distinct, yet morphologically similar (i.e. cryptic) species. Moreover, there was also separation of the different populations of snails (i.e. the first intermediate hosts) into two distinct genetic groups that corresponded with the delineation of O. viverrini into two species. This suggests that there may be a history of co-evolution in this host-parasite lineage. Additionally, five distinct genetic groups of parasites were detected, each of which occurred within a different and independent river wetland system. Our findings have major implications for the implementation of effective control and surveillance programs targeted to these medically important food-borne parasites.

  8. Pathogenic Mineralization of Calcium Phosphate on Human Heart Valves

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cases of rheumatic heart disease (RHD) always occur with fibrotic and calcified tissue of heart valve. In this article, samples taken from calcified human heart valves were studied. The characterization was performed by scanning electronic micrascope, X-ray Diffraction and transmission electron microscopy with selective diffraction patterns. It is found for the first time that calcium phosphate grains existing in the calcified human heart valves contain octacalcium phosphate (OCP).

  9. Pathogens and host immunity in the ancient human oral cavity

    DEFF Research Database (Denmark)

    Warinner, Christina; Rodrigues, João F Matias; Vyas, Rounak

    2014-01-01

    cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction......Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first, to our knowledge, high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral...... of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing confirmation of a long-term association between host immune factors, 'red complex' pathogens and periodontal disease, and (vi) DNA sequences matching dietary sources. Directly datable and nearly ubiquitous, dental...

  10. Transfer of tetracycline resistance genes with aggregation substance in food-borne Enterococcus faecalis.

    Science.gov (United States)

    Choi, Jong-Mi; Woo, Gun-Jo

    2015-04-01

    Enterococcus faecalis has the ability to conjugate with the aid of aggregation substance (AS) and inducible sex pheromones to exchange genetic elements in food matrix. To evaluate the food safety condition and the transferable factor, 250 tetracycline-resistant food-borne E. faecalis were collected in Korea. Among the isolates, a majority of tetracycline-resistant isolates (49.6 %) harbored both the tet(M) and tet(L) genes together, followed by tet(M) (19.6 %), and tet(L) (6.8 %) alone. Also, we found the combination of tet(L)/tet(M)/tet(O) or tet(M)/tet(O). We identified two tet(S) genes including the isolate carrying tet(M) + tet(S) genes. Additionally, most E. faecalis were positive for cpd and ccf (both 96.8 %) followed by cob (57.2 %). Through mating experiments, we confirmed E. faecalis possessing the Int-Tn gene and/or any AS gene successfully transferred tet genes to JH2-2 E. faecalis, whereas neither E. faecalis carrying AS genes nor the Int-Tn gene showed the conjugation. Pulsed-field gel electrophoresis results supported a distinct pattern, implying transfer of genetic information. Our study revealed a high occurrence of tetracycline resistance genes in E. faecalis from various foods. The widespread dissemination of tetracycline resistance genes would be promoted to transfer tetracycline resistance genes by pheromone-mediated conjugation systems.

  11. Genetic Relatedness among Hepatitis A Virus Strains Associated with Food-Borne Outbreaks

    Science.gov (United States)

    Vaughan, Gilberto; Xia, Guoliang; Forbi, Joseph C.; Purdy, Michael A.; Rossi, Lívia Maria Gonçalves; Spradling, Philip R.; Khudyakov, Yury E.

    2013-01-01

    The genetic characterization of hepatitis A virus (HAV) strains is commonly accomplished by sequencing subgenomic regions, such as the VP1/P2B junction. HAV genome is not extensively variable, thus presenting opportunity for sharing sequences of subgenomic regions among genetically unrelated isolates. The degree of misrepresentation of phylogenetic relationships by subgenomic regions is especially important for tracking transmissions. Here, we analyzed whole-genome (WG) sequences of 101 HAV strains identified from 4 major multi-state, food-borne outbreaks of hepatitis A in the Unites States and from 14 non-outbreak-related HAV strains that shared identical VP1/P2B sequences with the outbreak strains. Although HAV strains with an identical VP1/P2B sequence were specific to each outbreak, WG were different, with genetic diversity reaching 0.31% (mean 0.09%). Evaluation of different subgenomic regions did not identify any other section of the HAV genome that could accurately represent phylogenetic relationships observed using WG sequences. The identification of 2–3 dominant HAV strains in 3 out of 4 outbreaks indicates contamination of the implicated food items with a heterogeneous HAV population. However, analysis of intra-host HAV variants from eight patients involved in one outbreak showed that only a single sequence variant established infection in each patient. Four non-outbreak strains were found closely related to strains from 2 outbreaks, whereas ten were genetically different from the outbreak strains. Thus, accurate tracking of HAV strains can be accomplished using HAV WG sequences, while short subgenomic regions are useful for identification of transmissions only among cases with known epidemiological association. PMID:24223112

  12. Research on Effect of Aerobic Exercise and Nutrition Intervention on Food-borne Obesity

    Directory of Open Access Journals (Sweden)

    Xiaohong Wang

    2015-09-01

    Full Text Available With the development of social economy and the improvement of people's living standards, the incidence of obesity is increasing year by year. The main purpose of this study is to study the effect to food-borne obese rats combined aerobic exercise with soybean peptide and L-carnitine. The objects of this experiment are the SD obese rats which are successfully modeling, with 6-week training on treadmill and lavaging 10% of nutrient solution everyday (600 mg/ (kg•day L-carnitine and 15 mg/ (kg•day soybean peptide. But for the obese rats in the control group, they will be lavaged with 2 mL of distilled water. During this experiment, we observed the body weight, body length of the obese rats and calculate Lee’s index, detect the index of body weight, body length and the concentration of apolipoprotein. After the experiment, the exercise intervention group, the nutrition intervention group and exercise plus nutrition intervention group, Lee’s indexes of them are obviously lower than obese control group. The differences between two are all significant (p0.05; Nutrition intervention, exercise intervention group and sport plus nutrition intervention all significantly decreased the levels of apoB (p0.05, but sport plus nutrition intervention effect on apoA of obese rats has significant difference (p<0.05. Through the analysis of these results, the experiment shows that feeding high fat and sugar fodder can successful establish obese rats model. Exercise and nutrition intervention can improve lipid metabolism, significantly decreasing apoB concentrations of obese rats, increasing apoA concentrations.

  13. Origin Detection During Food-borne Disease Outbreaks - A Case Study of the 2011 EHEC/HUS Outbreak in Germany.

    Science.gov (United States)

    Manitz, Juliane; Kneib, Thomas; Schlather, Martin; Helbing, Dirk; Brockmann, Dirk

    2014-04-01

    The key challenge during food-borne disease outbreaks, e.g. the 2011 EHEC/HUS outbreak in Germany, is the design of efficient mitigation strategies based on a timely identification of the outbreak's spatial origin. Standard public health procedures typically use case-control studies and tracings along food shipping chains. These methods are time-consuming and suffer from biased data collected slowly in patient interviews. Here we apply a recently developed, network-theoretical method to identify the spatial origin of food-borne disease outbreaks. Thereby, the network captures the transportation routes of contaminated foods. The technique only requires spatial information on case reports regularly collected by public health institutions and a model for the underlying food distribution network. The approach is based on the idea of replacing the conventional geographic distance with an effective distance that is derived from the topological structure of the underlying food distribution network. We show that this approach can efficiently identify most probable epicenters of food-borne disease outbreaks. We assess and discuss the method in the context of the 2011 EHEC epidemic. Based on plausible assumptions on the structure of the national food distribution network, the approach can correctly localize the origin of the 2011 German EHEC/HUS outbreak.

  14. Natural soil reservoirs for human pathogenic and fecal indicator bacteria

    Science.gov (United States)

    Boschiroli, Maria L; Falkinham, Joseph; Favre-Bonte, Sabine; Nazaret, Sylvie; Piveteau, Pascal; Sadowsky, Michael J.; Byappanahalli, Muruleedhara; Delaquis, Pascal; Hartmann, Alain

    2016-01-01

    Soils receive inputs of human pathogenic and indicator bacteria through land application of animal manures or sewage sludge, and inputs by wildlife. Soil is an extremely heterogeneous substrate and contains meso- and macrofauna that may be reservoirs for bacteria of human health concern. The ability to detect and quantify bacteria of human health concern is important in risk assessments and in evaluating the efficacy of agricultural soil management practices that are protective of crop quality and protective of adjacent water resources. The present chapter describes the distribution of selected Gram-positive and Gram-negative bacteria in soils. Methods for detecting and quantifying soilborne bacteria including extraction, enrichment using immunomagnetic capture, culturing, molecular detection and deep sequencing of metagenomic DNA to detect pathogens are overviewed. Methods for strain phenotypic and genotypic characterization are presented, as well as how comparison with clinical isolates can inform the potential for human health risk.

  15. Salmonella Typhi: from a Human Pathogen to a Vaccine Vector

    Institute of Scientific and Technical Information of China (English)

    Xiao-Lian Zhang; Victor Tunje Jeza; Qin Pan

    2008-01-01

    Salmonella (S.) typhi is an important intracellular pathogen. Among the more than 2,300 closely-related Salmonella serovars bacteria recognized, S. Typhi is the only one that is pathogenic exclusively for humans, in whom it causes typhoid or enteric fever. The pathogen has been around for many years and many studies have been done in an effort to combat it. Molecular and biologic features of S. Typhi and host factors and immune responses involved in Salmonella invasion have been extensively studies. Vaccines that have been developed most notably are Vi polysaccharide and Ty21a. However, as the results show, there is still a long way to go. It is also shown that multi-drug resistance has occurred to the few available antibiotics. More and more studies have shown that Salmonella can be used as a vaccine vector carrying antigens of other pathogens. This has been promising in that the immune system can be elicited in response to both the Salmonella bacteria and the antigen of the pathogen in question. This review aims to highlight some of the milestones attained in the fight against the disease from the time S. Typhi was seen as a pathogen causing typhoid fever to the use of Salmonella as a vaccine vector.

  16. Comparative genomics and the evolution of pathogenicity in human pathogenic fungi.

    LENUS (Irish Health Repository)

    Moran, Gary P

    2011-01-01

    Because most fungi have evolved to be free-living in the environment and because the infections they cause are usually opportunistic in nature, it is often difficult to identify specific traits that contribute to fungal pathogenesis. In recent years, there has been a surge in the number of sequenced genomes of human fungal pathogens, and comparison of these sequences has proved to be an excellent resource for exploring commonalities and differences in how these species interact with their hosts. In order to survive in the human body, fungi must be able to adapt to new nutrient sources and environmental stresses. Therefore, genes involved in carbohydrate and amino acid metabolism and transport and genes encoding secondary metabolites tend to be overrepresented in pathogenic species (e.g., Aspergillus fumigatus). However, it is clear that human commensal yeast species such as Candida albicans have also evolved a range of specific factors that facilitate direct interaction with host tissues. The evolution of virulence across the human pathogenic fungi has occurred largely through very similar mechanisms. One of the most important mechanisms is gene duplication and the expansion of gene families, particularly in subtelomeric regions. Unlike the case for prokaryotic pathogens, horizontal transfer of genes between species and other genera does not seem to have played a significant role in the evolution of fungal virulence. New sequencing technologies promise the prospect of even greater numbers of genome sequences, facilitating the sequencing of multiple genomes and transcriptomes within individual species, and will undoubtedly contribute to a deeper insight into fungal pathogenesis.

  17. Aeromonas dhakensis, an increasingly recognized human pathogen

    Directory of Open Access Journals (Sweden)

    Po Lin eChen

    2016-05-01

    Full Text Available Aeromonas dhakensis was first isolated from children with diarrhea in Dhaka, Bangladesh and described in 2002. In the past decade, increasing evidence indicate this species is widely distributed in the environment and can cause a variety of infections both in human and animals, especially in coastal areas. A. dhakensis is often misidentified as A. hydrophila, A. veronii or A. caviae by commercial phenotypic tests in the clinical laboratory. Correct identification relies on molecular methods. Increasingly used matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS may be able to identify Aeromonas specie rapidly and accurately. A. dhakensis has shown its potent virulence in different animal models and clinical infections. Although several virulence factors had been reported, no single mechanism is conclusive. Characteristically A. dhakensis is the principal species causing soft tissue infection and bacteremia, especially among patients with liver cirrhosis or malignancy. Of note, A. dhakensis bacteremia is more lethal than bacteremia due to other Aeromonas species. The role of this species in gastroenteritis remains controversial. Third generation cephalosporins and carbapenems should be used cautiously in the treatment of severe A. dhakensis infection due to the presence of AmpC β-lactamase and metallo-β-lactamase genes, and optimal regimens may be cefepime or fluoroquinolones. Studies of bacterial virulence factors and associated host responses may provide the chance to understand the heterogeneous virulence between species. The hypothesis A. dhakensis with varied geographic prevalence and enhanced virulence that compared to other Aeromonas species warrants more investigations.

  18. Galleria mellonella as a model host for human pathogens

    Science.gov (United States)

    Junqueira, Juliana Campos

    2012-01-01

    The number of studies using G. mellonella as a model host for human pathogens has increased significantly in the last few years. Important studies were published from different countries for evaluating the pathogenesis of bacterial and fungal infections and for exploring the host defenses against pathogens. Therefore, standardized conditions for the use of G. melonella larvae need to be established. Recent research showed that the deprivation of G. mellonella larvae of food during the experiment caused a reduction in immune responses and an increased susceptibility to infection, suggesting that incubating of larvae in the presence or absence of nutrition may affect the results and comparisons among different laboratories. PMID:23211681

  19. Human commensals producing a novel antibiotic impair pathogen colonization.

    Science.gov (United States)

    Zipperer, Alexander; Konnerth, Martin C; Laux, Claudia; Berscheid, Anne; Janek, Daniela; Weidenmaier, Christopher; Burian, Marc; Schilling, Nadine A; Slavetinsky, Christoph; Marschal, Matthias; Willmann, Matthias; Kalbacher, Hubert; Schittek, Birgit; Brötz-Oesterhelt, Heike; Grond, Stephanie; Peschel, Andreas; Krismer, Bernhard

    2016-07-28

    The vast majority of systemic bacterial infections are caused by facultative, often antibiotic-resistant, pathogens colonizing human body surfaces. Nasal carriage of Staphylococcus aureus predisposes to invasive infection, but the mechanisms that permit or interfere with pathogen colonization are largely unknown. Whereas soil microbes are known to compete by production of antibiotics, such processes have rarely been reported for human microbiota. We show that nasal Staphylococcus lugdunensis strains produce lugdunin, a novel thiazolidine-containing cyclic peptide antibiotic that prohibits colonization by S. aureus, and a rare example of a non-ribosomally synthesized bioactive compound from human-associated bacteria. Lugdunin is bactericidal against major pathogens, effective in animal models, and not prone to causing development of resistance in S. aureus. Notably, human nasal colonization by S. lugdunensis was associated with a significantly reduced S. aureus carriage rate, suggesting that lugdunin or lugdunin-producing commensal bacteria could be valuable for preventing staphylococcal infections. Moreover, human microbiota should be considered as a source for new antibiotics.

  20. The poultry red mite (Dermanyssus gallinae): a potential vector of pathogenic agents.

    Science.gov (United States)

    Valiente Moro, Claire; De Luna, Carlos J; Tod, Alexander; Guy, Jonathan H; Sparagano, Olivier A E; Zenner, Lionel

    2009-06-01

    The poultry red mite, D. gallinae has been involved in the transmission of many pathogenic agents, responsible for serious diseases both in animals and humans. Nowadays, few effective methods are available to control the ectoparasite in poultry farms. Consequently, this is an emerging problem which must be taken into account to maintain good health in commercial egg production. This paper addresses the vector capacity of the ectoparasite with special emphasis on salmonellae, pathogenic agents responsible for many of the most important outbreaks of food-borne diseases worlwide. It has been experimentally shown that D. gallinae could act as a biological vector of S. enteritidis and natural carriage of these bacteria by the mite on poultry premises has also been reported. It was also found that D. gallinae carried other pathogens such as E. coli, Shigella sp., and Staphylococcus, thus increasing the list of pathogenic agents potentially transmitted by the mite.

  1. Extracellular proteolytic enzymes produced by human pathogenic Vibrio species

    Directory of Open Access Journals (Sweden)

    Shin-Ichi eMiyoshi

    2013-11-01

    Full Text Available Bacteria in the genus Vibrio produce extracellular proteolytic enzymes to obtain nutrients via digestion of various protein substrates. However, the enzymes secreted by human pathogenic species have been documented to modulate the bacterial virulence. Several species including Vibrio cholerae and V. vulnificus are known to produce thermolysin-like metalloproteases termed vibriolysin. The vibriolysin from V. vulnificus, a causative agent of serious systemic infection, is a major toxic factor eliciting the secondary skin damage characterized by formation of the hemorrhagic brae. The vibriolysin from intestinal pathogens may play indirect roles in pathogenicity because it can activate protein toxins and hemagglutinin by the limited proteolysis and can affect the bacterial attachment to or detachment from the intestinal surface by degradation of the mucus layer. Two species causing wound infections, V. alginolyticus and V. parahaemolyticus, produce another metalloproteases so-called collagenases. Although the detailed pathological roles have not been studied, the collagenase is potent to accelerate the bacterial dissemination through digestion of the protein components of the extracellular matrix. Some species produce cymotrypsin-like serine proteases, which may also affect the bacterial virulence potential. The intestinal pathogens produce sufficient amounts of the metalloprotease at the small intestinal temperature; however, the metalloprotease production by extra-intestinal pathogens is much higher around the body surface temperature. On the other hand, the serine protease is expressed only in the absence of the metalloprotease.

  2. Pathogen-Driven Selection in the Human Genome

    Directory of Open Access Journals (Sweden)

    Rachele Cagliani

    2013-01-01

    Full Text Available Infectious diseases and epidemics have always accompanied and characterized human history, representing one of the main causes of death. Even today, despite progress in sanitation and medical research, infections are estimated to account for about 15% of deaths. The hypothesis whereby infectious diseases have been acting as a powerful selective pressure was formulated long ago, but it was not until the availability of large-scale genetic data and the development of novel methods to study molecular evolution that we could assess how pervasively infectious agents have shaped human genetic diversity. Indeed, recent evidences indicated that among the diverse environmental factors that acted as selective pressures during the evolution of our species, pathogen load had the strongest influence. Beside the textbook example of the major histocompatibility complex, selection signatures left by pathogen-exerted pressure can be identified at several human loci, including genes not directly involved in immune response. In the future, high-throughput technologies and the availability of genetic data from different populations are likely to provide novel insights into the evolutionary relationships between the human host and its pathogens. Hopefully, this will help identify the genetic determinants modulating the susceptibility to infectious diseases and will translate into new treatment strategies.

  3. Integral membrane pyrophosphatases: a novel drug target for human pathogens?

    Directory of Open Access Journals (Sweden)

    Henri Xhaard

    2016-03-01

    Full Text Available Membrane-integral pyrophosphatases (mPPases are found in several human pathogens, including Plasmodium species, the protozoan parasites that cause malaria. These enzymes hydrolyze pyrophosphate and couple this to the pumping of ions (H+ and/or Na+ across a membrane to generate an electrochemical gradient. mPPases play an important role in stress tolerance in plants, protozoan parasites, and bacteria. The solved structures of mPPases from Vigna radiata and Thermotoga maritima open the possibility of using structure-based drug design to generate novel molecules or repurpose known molecules against this enzyme. Here, we review the current state of knowledge regarding mPPases, focusing on their structure, the proposed mechanism of action, and their role in human pathogens. We also summarize different methodologies in structure-based drug design and propose an example region on the mPPase structure that can be exploited by these structure-based methods for drug targeting. Since mPPases are not found in animals and humans, this enzyme is a promising potential drug target against livestock and human pathogens.

  4. Essential metals at the host-pathogen interface: nutritional immunity and micronutrient assimilation by human fungal pathogens.

    Science.gov (United States)

    Crawford, Aaron; Wilson, Duncan

    2015-11-01

    The ability of pathogenic microorganisms to assimilate sufficient nutrients for growth within their hosts is a fundamental requirement for pathogenicity. However, certain trace nutrients, including iron, zinc and manganese, are actively withheld from invading pathogens in a process called nutritional immunity. Therefore, successful pathogenic species must have evolved specialized mechanisms in order to adapt to the nutritionally restrictive environment of the host and cause disease. In this review, we discuss recent advances which have been made in our understanding of fungal iron and zinc acquisition strategies and nutritional immunity against fungal infections, and explore the mechanisms of micronutrient uptake by human pathogenic fungi.

  5. Association between the Hygiene Index Values of Live Fresh Aquatic Products and Food-Borne Diarrhea in the Population of the Ningbo Area in China

    Directory of Open Access Journals (Sweden)

    Lijun Zhang

    2015-08-01

    Full Text Available To investigate the association of the hygiene index values of live fresh aquatic products and food-borne diarrhea in the population of the Ningbo area in China. Volatile basic nitrogen (VBN, histamine (HIS, indole, tetrodotoxin (TTX, and paralytic, neurotoxic, amnesic and diarrhetic shellfish poisons (PSP, NSP, ASP, and DSP, respectively in the samples of live fresh aquatic products and food-borne diarrhea cases in six studied districts were analyzed. Results indicate that the incidence rate of food-borne diarrhea is related to the hygiene index values. Aside from VBN, the main risk factors related to food-borne diarrhea in edible aquatic products include DSP (in marine fish, shrimp, and other shellfishes, NSP, and ASP (in marine shrimp and crab. Hygiene index values among different species were significantly different. No significant difference in the monitoring index values was found among the six different studied districts. The reported cases of food-borne diarrhea were positively associated with VBN and DSP in aquatic products in Haishu, Jiangbei, Zhenhai, and Beilun, as well as VBN and NSP in aquatic products in Jiangdong and Yinzhou. In conclusion, VBN, DSP, NSP, and ASP are important risk factors for the occurring of food-borne diarrhea in the population of the Ningbo area in China.

  6. Human herpesvirus 8 – A novel human pathogen

    Directory of Open Access Journals (Sweden)

    Edelman Daniel C

    2005-09-01

    Full Text Available Abstract In 1994, Chang and Moore reported on the latest of the gammaherpesviruses to infect humans, human herpesvirus 8 (HHV-8 1. This novel herpesvirus has and continues to present challenges to define its scope of involvement in human disease. In this review, aspects of HHV-8 infection are discussed, such as, the human immune response, viral pathogenesis and transmission, viral disease entities, and the virus's epidemiology with an emphasis on HHV-8 diagnostics.

  7. Bats as reservoir hosts of human bacterial pathogen, Bartonella mayotimonensis.

    Science.gov (United States)

    Veikkolainen, Ville; Vesterinen, Eero J; Lilley, Thomas M; Pulliainen, Arto T

    2014-06-01

    A plethora of pathogenic viruses colonize bats. However, bat bacterial flora and its zoonotic threat remain ill defined. In a study initially conducted as a quantitative metagenomic analysis of the fecal bacterial flora of the Daubenton's bat in Finland, we unexpectedly detected DNA of several hemotrophic and ectoparasite-transmitted bacterial genera, including Bartonella. Bartonella spp. also were either detected or isolated from the peripheral blood of Daubenton's, northern, and whiskered bats and were detected in the ectoparasites of Daubenton's, northern, and Brandt's bats. The blood isolates belong to the Candidatus-status species B. mayotimonensis, a recently identified etiologic agent of endocarditis in humans, and a new Bartonella species (B. naantaliensis sp. nov.). Phylogenetic analysis of bat-colonizing Bartonella spp. throughout the world demonstrates a distinct B. mayotimonensis cluster in the Northern Hemisphere. The findings of this field study highlight bats as potent reservoirs of human bacterial pathogens.

  8. ANTIMICROBIAL ACTIVITIES OF RICINUS COMMUNIS AGAINST SOME HUMAN PATHOGENS

    OpenAIRE

    Kushwah Poonam; Singh Krishan Pratap

    2012-01-01

    The present paper deals with the antimicrobial activities of seed extracts of Ricinus communis against some human pathogenic bacteria namely Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Escherichia coli and two fungal strains namely Candida albicans and Candida glabrata. The aqueous and methanol extracts of seeds were screened for their antibacterial activity using agar disc diffusion method. The aqueous seed extracts were less active but methanol extracts showed high degree zon...

  9. Mice with human immune system components as in vivo models for infections with human pathogens.

    Science.gov (United States)

    Rämer, Patrick C; Chijioke, Obinna; Meixlsperger, Sonja; Leung, Carol S; Münz, Christian

    2011-03-01

    Many pathogens relevant to human disease do not infect other animal species. Therefore, animal models that reconstitute or harbor human tissues are explored as hosts for these. In this review, we will summarize recent advances to utilize mice with human immune system components, reconstituted from hematopoietic progenitor cells in vivo. Such mice can be used to study human pathogens that replicate in leukocytes. In addition to studying the replication of these pathogens, the reconstituted human immune system components can also be analyzed for initiating immune responses and control against these infections. Moreover, these new animal models of human infectious disease should replicate the reactivity of the human immune system to vaccine candidates and, especially, the adjuvants contained in them, more faithfully.

  10. Comamonas testosteroni: Is It Still a Rare Human Pathogen?

    Science.gov (United States)

    Farooq, Shaika; Farooq, Rumana; Nahvi, Nahida

    2017-01-01

    Comamonas testosteroni (formally Pseudomonas testosteroni) is common environmental bacterium that is not part of the human microbiome. Since its identification as a human pathogen in 1987, numerous reports have drizzled in, implicating this organism for various infections. Although these organisms are of low virulence, some of their obscurity perhaps is due to the incapability of clinical laboratories to identify them. Most of the reported cases are bloodstream infections. We report a case of gastroenteritis caused by this organism in a 65-year-old female with colostomy in situ. PMID:28203137

  11. First description of food-borne Salmonella enterica resistance regions R1 and R3 associated with IS26 elements

    OpenAIRE

    Eduarda Gomes-Neves; Vera Manageiro; Eugénia Ferreira; José M Correia da Costa; Manuela Caniça

    2015-01-01

    In this study, we assessed the presence of IS26 in food-borne ASSuT-type Salmonella enterica isolates. A new genetic region (R3) wasdescribed, that included a C14 caspase gene between IS26 elements. R3 was present in two Salmonella Rissen isolates from a swine carcass anda meat handler, collected at the same abattoir. Furthermore, a new rearrangement of resistance region R1, harboring the blaTEM-1 gene flanked byIS26 elements, was identified in Salmonella Typhimurium and Salmonella 4,[5],12:i...

  12. First description of food-borne Salmonella enterica resistance regions R1 and R3 associated with IS26 elements

    OpenAIRE

    Gomes-Neves, Eduarda; Manageiro, Vera; Ferreira, Eugénia; José M Correia da Costa; Caniça, Manuela

    2015-01-01

    In this study, we assessed the presence of IS26 in food-borne ASSuT-type Salmonella enterica isolates. A new genetic region (R3) was described, that included a C14 caspase gene between IS26 elements. R3 was present in two Salmonella Rissen isolates from a swine carcass and a meat handler, collected at the same abattoir. Furthermore, a new rearrangement of resistance region R1, harboring the blaTEM-1 gene flanked by IS26 elements, was identified in Salmonella Typhimurium and Salmonella 4,[5],1...

  13. 革兰氏阳性食源性致病菌%G+ Food-borne Pathogens Bacteria

    Institute of Scientific and Technical Information of China (English)

    龚霄; 陈盼

    2008-01-01

    本文针对肉制品中常常出现的肉毒梭菌(Clostridium botulinum)、产气英膜杆菌(Clostridium perfringens)、单增李斯特菌(Listeria monocytongenes)、蜡样芽胞杆菌(Bacillus cereus)和金黄色葡萄球(Staphylococcus aureus)等五种重要的G+食源性致病菌的生物学特性、致病性、流行病学特征、检测方法和控制措施作一综述.

  14. Development of molecular-based techniques for the detection, identification and quantification of food-borne pathogens

    OpenAIRE

    2004-01-01

    La presencia de microorganismos patógenos en alimentos es uno de los problemas esenciales en salud pública, y las enfermedades producidas por los mismos es una de las causas más importantes de enfermedad. Por tanto, la aplicación de controles microbiológicos dentro de los programas de aseguramiento de la calidad es una premisa para minimizar el riesgo de infección de los consumidores. Los métodos microbiológicos clásicos requieren, en general, el uso de pre-enriquecimientos no-selectivos,enri...

  15. Antibacterial Activity of Plant Extracts Against Food-Borne Pathogens and Spoilage Bacteria In Vitro and on Poultry Skin

    Science.gov (United States)

    Some plant extracts are known to contain substances that inhibit the growth of bacteria; therefore, experiments were conducted to examine the ability of extracts of pomegranate, orange, and lemon peels to inhibit the growth of five bacteria associated with processed poultry. The antibacterial activi...

  16. Inhibitory effect of the essential oil from Chamaecyparis obtusa on the growth of food-borne pathogens.

    Science.gov (United States)

    Park, Mi-Jin; Choi, Won-Sil; Kang, Ha-Young; Gwak, Ki-Seob; Lee, Geun-Shik; Jeung, Eui-Bae; Choi, In-Gyu

    2010-08-01

    In this study, the antibacterial activity of essential oil from Chamaecyparis obtusa (Sieb. et Zucc) leaves and twigs was investigated. The test strains were Klebsiella pneumoniae, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Escherichia coli, Legionella pneumophila, and Methicilline-resistant Staphylococcus aureus. Antibacterial activity was estimated by measuring bacterial growth inhibition. Histopathological examination was also performed. C. obtusa oil distinctly inhibited the growth of all test strains and exhibited the strongest antibacterial activity against L. monocytogenes. It was chromatographically divided into several fractions. The fractions were further tested against antibacterial activity and their chemical compositions were analyzed. The fraction containing terpinen-4-ol (TA) showed high antibacterial activity toward all strains tested. Tests with authentic samples showed that TA played a major role in the antibacterial activity of C. obtusa oil, and in a mice test, the oil actively minimized inflammation by S. aureus.

  17. A novel CMOS image sensor system for quantitative loop-mediated isothermal amplification assays to detect food-borne pathogens.

    Science.gov (United States)

    Wang, Tiantian; Kim, Sanghyo; An, Jeong Ho

    2017-02-01

    Loop-mediated isothermal amplification (LAMP) is considered as one of the alternatives to the conventional PCR and it is an inexpensive portable diagnostic system with minimal power consumption. The present work describes the application of LAMP in real-time photon detection and quantitative analysis of nucleic acids integrated with a disposable complementary-metal-oxide semiconductor (CMOS) image sensor. This novel system works as an amplification-coupled detection platform, relying on a CMOS image sensor, with the aid of a computerized circuitry controller for the temperature and light sources. The CMOS image sensor captures the light which is passing through the sensor surface and converts into digital units using an analog-to-digital converter (ADC). This new system monitors the real-time photon variation, caused by the color changes during amplification. Escherichia coli O157 was used as a proof-of-concept target for quantitative analysis, and compared with the results for Staphylococcus aureus and Salmonella enterica to confirm the efficiency of the system. The system detected various DNA concentrations of E. coli O157 in a short time (45min), with a detection limit of 10fg/μL. The low-cost, simple, and compact design, with low power consumption, represents a significant advance in the development of a portable, sensitive, user-friendly, real-time, and quantitative analytic tools for point-of-care diagnosis.

  18. Bioaccumulation Experiments in Mussels Contaminated with the Food-Borne Pathogen Arcobacter butzleri: Preliminary Data for Risk Assessment

    Directory of Open Access Journals (Sweden)

    Donatella Ottaviani

    2013-01-01

    Full Text Available The aim of this study was to evaluate, at a laboratory scale, the ability of this microorganism to grow in seawater and bioaccumulate in mussels (Mytilus galloprovincialis maintained in constantly aerated tanks, containing twenty litres of artificial seawater. Three concentrations of A. butzleri LMG 10828T were tested (about 5×106 CFU/mL, 5×104 CFU/mL, and 5×102 CFU/mL. Following contamination, enumeration of A. butzleri was performed from water and mussels each day, for up to 96 h. Three contamination experiments with artificial seawater in absence of mussels were also performed in the same manner. In the experiments with mussels, A. butzleri declined in water of approximately 1 log every 24 h from the contamination. In artificial seawater without mussels the concentration of A. butzleri remained on the same logarithmic level in the first 48 h and then decreased of about 1 log every 24 hours. In mussels, the concentration was approximately 2 log lower than the exposition level after 24 h from the contamination, and then it decreased exponentially of 1 log every 24 h. Our findings suggest that in the experimental conditions tested A. butzleri is neither able to effectively grow in seawater nor bioaccumulate in mussels, at least in the free and cultivable form.

  19. Probiotic Activity of Saccharomyces cerevisiae var. boulardii Against Human Pathogens

    Directory of Open Access Journals (Sweden)

    Katarzyna Rajkowska

    2012-01-01

    Full Text Available Infectious diarrhoea is associated with a modification of the intestinal microflora and colonization of pathogenic bacteria. Tests were performed for seven probiotic yeast strains of Saccharomyces cerevisiae var. boulardii, designated for the prevention and treatment of diarrhoea. To check their possible effectiveness against diarrhoea of different etiologies, the activity against a variety of human pathogenic or opportunistic bacteria was investigated in vitro. In mixed cultures with S. cerevisiae var. boulardii, a statistically significant reduction was observed in the number of cells of Listeria monocytogenes, Pseudomonas aeruginosa and Staphylococcus aureus, by even 55.9 % in the case of L. monocytogenes compared with bacterial monocultures. The influence of yeasts was mostly associated with the shortening of the bacterial lag phase duration, more rapid achievement of the maximum growth rates, and a decrease by 4.4–57.1 % (L. monocytogenes, P. aeruginosa, or an increase by 1.4–70.6 % (Escherichia coli, Enterococcus faecalis, Salmonella Typhimurium in the exponential growth rates. Another issue included in the research was the ability of S. cerevisiae var. boulardii to bind pathogenic bacteria to its cell surface. Yeasts have shown binding capacity of E. coli, S. Typhimurium and additionally of S. aureus, Campylobacter jejuni and E. faecalis. However, no adhesion of L. monocytogenes and P. aeruginosa to the yeast cell wall was noted. The probiotic activity of S. cerevisiae var. boulardii against human pathogens is related to a decrease in the number of viable and active cells of bacteria and the binding capacity of yeasts. These processes may limit bacterial invasiveness and prevent bacterial adherence and translocation in the human intestines.

  20. The effects of antibiotic usage in food animals on the development of antimicrobial resistance of importance for humans in Campylobacter and Escherichia coli.

    Science.gov (United States)

    Aarestrup, F M; Wegener, H C

    1999-07-01

    Modern food animal production depends on use of large amounts of antibiotics for disease control. This provides favourable conditions for the spread and persistence of antimicrobial-resistant zoonotic bacteria such as Campylobacter and E. coli O157. The occurrence of antimicrobial resistance to antimicrobials used in human therapy is increasing in human pathogenic Campylobacter and E. coli from animals. There is an urgent need to implement strategies for prudent use of antibiotics in food animal production to prevent further increases in the occurrence of antimicrobial resistance in food-borne human pathogenic bacteria such as Campylobacter and E. coli.

  1. The rhizosphere microbiome: significance of plant beneficial, plant pathogenic, and human pathogenic microorganisms.

    Science.gov (United States)

    Mendes, Rodrigo; Garbeva, Paolina; Raaijmakers, Jos M

    2013-09-01

    Microbial communities play a pivotal role in the functioning of plants by influencing their physiology and development. While many members of the rhizosphere microbiome are beneficial to plant growth, also plant pathogenic microorganisms colonize the rhizosphere striving to break through the protective microbial shield and to overcome the innate plant defense mechanisms in order to cause disease. A third group of microorganisms that can be found in the rhizosphere are the true and opportunistic human pathogenic bacteria, which can be carried on or in plant tissue and may cause disease when introduced into debilitated humans. Although the importance of the rhizosphere microbiome for plant growth has been widely recognized, for the vast majority of rhizosphere microorganisms no knowledge exists. To enhance plant growth and health, it is essential to know which microorganism is present in the rhizosphere microbiome and what they are doing. Here, we review the main functions of rhizosphere microorganisms and how they impact on health and disease. We discuss the mechanisms involved in the multitrophic interactions and chemical dialogues that occur in the rhizosphere. Finally, we highlight several strategies to redirect or reshape the rhizosphere microbiome in favor of microorganisms that are beneficial to plant growth and health. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  2. Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis

    Science.gov (United States)

    Desjardins, Christopher A.; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailão, Alexandre M.; Brigido, Marcelo Macedo; Ferreira, Márcia Eliana da Silva; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; León-Narváez, Henry; Longo, Larissa V. G.; Ma, Li-Jun; Malavazi, Iran; Matsuo, Alisson L.; Morais, Flavia V.; Pereira, Maristela; Rodríguez-Brito, Sabrina; Sakthikumar, Sharadha; Salem-Izacc, Silvia M.; Sykes, Sean M.; Teixeira, Marcus Melo; Vallejo, Milene C.; Walter, Maria Emília Machado Telles; Yandava, Chandri; Young, Sarah; Zeng, Qiandong; Zucker, Jeremy; Felipe, Maria Sueli; Goldman, Gustavo H.; Haas, Brian J.; McEwen, Juan G.; Nino-Vega, Gustavo; Puccia, Rosana; San-Blas, Gioconda; Soares, Celia Maria de Almeida; Birren, Bruce W.; Cuomo, Christina A.

    2011-01-01

    Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of

  3. Comparative genomic analysis of human fungal pathogens causing paracoccidioidomycosis.

    Directory of Open Access Journals (Sweden)

    Christopher A Desjardins

    2011-10-01

    Full Text Available Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18 and one strain of Paracoccidioides lutzii (Pb01. These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic

  4. Antibacterial potential of three seagrasses against human pathogens

    Institute of Scientific and Technical Information of China (English)

    Rajasekaran Arumugam; Perumal Anantharaman

    2010-01-01

    Objective:To evaluate the antibacterial activity ofHalophila stipulacea (H. stipulacea), Cymodocea serrulata (C. serrulata) andHalodule pinifolia (H. pinifolia) against seven human bacterial pathogens.Methods:The antibacterial activities of the extracts on the various test organisms using disc diffusion method and Minimum Inhibitory Concentraction(MIC).Results:Methanol and chloroform extracts of all the three seagrasses were active against all the tested pathogens, whereas the hexane extract of seagrasses was not active againstStaphylococcus aureus (S. aureus). Antibacterial activity of three seagrass screened, was in the order ofH. pinifolia >H. stipulacea>C. serrulata.Conclusions: This antibacterial studies can further investigated on seagrasses for purification of bioactive substance and its possible utility in disease control.

  5. Bioactive berry compounds-novel tools against human pathogens.

    Science.gov (United States)

    Puupponen-Pimiä, Riitta; Nohynek, Liisa; Alakomi, Hanna-Leena; Oksman-Caldentey, Kirsi-Marja

    2005-04-01

    Berry fruits are rich sources of bioactive compounds, such as phenolics and organic acids, which have antimicrobial activities against human pathogens. Among different berries and berry phenolics, cranberry, cloudberry, raspberry, strawberry and bilberry especially possess clear antimicrobial effects against, e.g. Salmonella and Staphylococcus. Complex phenolic polymers, like ellagitannins, are strong antibacterial agents present in cloudberry and raspberry. Several mechanisms of action in the growth inhibition of bacteria are involved, such as destabilisation of cytoplasmic membrane, permeabilisation of plasma membrane, inhibition of extracellular microbial enzymes, direct actions on microbial metabolism and deprivation of the substrates required for microbial growth. Antimicrobial activity of berries may also be related to antiadherence of bacteria to epithelial cells, which is a prerequisite for colonisation and infection of many pathogens. Antimicrobial berry compounds may have important applications in the future as natural antimicrobial agents for food industry as well as for medicine. Some of the novel approaches are discussed.

  6. The action of berry phenolics against human intestinal pathogens.

    Science.gov (United States)

    Puupponen-Pimiä, Riitta; Nohynek, Liisa; Alakomi, Hanna-Leena; Oksman-Caldentey, Kirsi-Marja

    2005-01-01

    Phenolic compounds present in berries selectively inhibit the growth of human gastrointestinal pathogens. Especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. Complex phenolic polymers, such as ellagitannins, are strong antibacterial agents present in cloudberry, raspberry and strawberry. Berry phenolics seem to affect the growth of different bacterial species with different mechanisms. Adherence of bacteria to epithelial surfaces is a prerequisite for colonization and infection of many pathogens. Antimicrobial activity of berries may also be related to anti-adherence activity of the berries. Utilization of enzymes in berry processing increases the amount of phenolics and antimicrobial activity of the berry products. Antimicrobial berry compounds are likely to have many important applications in the future as natural antimicrobial agents for food industry as well as for medicine.

  7. 食源性疾病的风险控制%The Risk Control of The Food Borne Disease

    Institute of Scientific and Technical Information of China (English)

    赵桂华

    2016-01-01

    The food borne disease is a main problem in the food safety that it’s risk or harm is bigger. So we must control the food borne disease in the food safety risk by increasing the prevention idea and taking the peltinence ways to control the risk. We must reinforce the supervision production and finish the ilegality in order to avoid the food safety accident.%食源性疾病是食品安全问题中的主要问题,其风险大,危害性大,应成为食品安全风险控制的重点。应当提高预防意识,针对食源性疾病的致病原因,采取有针对性的风险控制对策。要加强对食品生产加工的监管,严惩人为造成食源性食品安全问题的违法行为,有效避免食品安全事故的发生。

  8. Two geographically separated food-borne outbreaks in Sweden linked by an unusual Cryptosporidium parvum subtype, October 2010.

    Science.gov (United States)

    Gherasim, A; Lebbad, M; Insulander, M; Decraene, V; Kling, A; Hjertqvist, M; Wallensten, A

    2012-11-15

    The number of sporadic cases of Cryptosporidium identified in the Stockholm county area increased above the expected limit during October 2010. Additionally, two food-borne outbreaks of cryptosporidiosis occurred in two other Swedish cities: Umeå (4 October) and Örebro (9 October). The outbreak investigations did not reveal any responsible food item, however fresh herbs were suspected. Thirty stool samples, originating from all three events, tested positive for Cryptosporidium oocysts. Polymerase chain reaction (PCR) and subsequent restriction fragment length polymorphism (RFLP) revealed that 27 individuals were infected with C. parvum, two with C. hominis, and one with C. felis. Using sequence analysis of the GP60 glycoprotein gene, a polymorphic marker with high intra-species diversity, we identified the same C. parvum subtype IIdA24G1 in samples from both the Umeå outbreak and the Stockholm area cases, thus indicating a possible outbreak in the Stockholm area and establishing a link between these two events. C. parvum IIdA24G1 has not previously been described in connection with a food-borne outbreak. For the outbreak in Örebro, another subtype was identified: C. parvum IIdA20G1e. These findings demonstrate that subtyping C. parvum isolates using GP60 gene amplification can be used to link cases in an outbreak investigation and we recommend its use in future similar events.

  9. [Arcobacter: a foodborne emerging pathogen].

    Science.gov (United States)

    Calvo, Gerardo; Arias, Maria Laura; Fernández, Heriberto

    2013-06-01

    In the last three decades, several emergent diseases affecting human beings have been identified, most of them from infectious origin including bacterial, viral, parasitic and even difficult to classify as spongiform encephalopathy. Most of these are zoonotic as it is the case of Arcobacter, currently considered as an emerging and food borne pathogen, of growing importance for public health. The increase in the prevalence and incidence of cases associated to this bacteria as well as in the number of actual researches and reports, suggest that the infection in human beings and animals has been underestimated due to a lack in knowledge about this bacteria and of a standardized isolation protocols, as well as the use of correct identification methods and techniques. Increasing trends in the isolation of Arcobacter from animal derivates used as food and from samples taken during production processes, cause an augment in public health awareness, since there is little knowledge about the pathogenic potential of Arcobacter species and the few focused in this bacterial group, show many different transmission routes and host species. Given this, the objective of the present review is to actualize the reader in the most important characteristics of this bacterium, including its morphology, distribution, classification, transmission, association with water, food, pets and animals, as well as the laboratory isolation techniques, virulence factors and their antibiotic susceptibility patterns.

  10. Some Pathogenic Bacteria of Livestock Origin as a Cause of Foodborne Diseases

    Directory of Open Access Journals (Sweden)

    Anni Kusumaningsih

    2010-09-01

    Full Text Available Food are essentialy required for cell metabolism in human physiologyc. Food should be free from biological, chemical, and physical contamination and also hazardous substances. All of them are able to disrupt physiological homeostatis resulting disorder or diseases. Diseases resulted by those contaminant are called food borne disease. One of the important contaminants is biological contaminant especially pathogenic bacterias. Some pathogenic bacteria such as Salmonella spp., Escherichia coli, Bacillus anthracis, Clostridium spp., Listeria monocytogenes, Campylobacter spp., Vibrio cholerae, Enterobacter sakazakii, Shigella, are able to cause symptomatic diseases. Overall, the general symptoms of the diseases due to pathogenic bacterial infection are gastric pain, nausea, vomit, headache, loss of appetite, fever, and also dehydration.

  11. Immunity to pathogens taught by specialized human dendritic cell subsets.

    Directory of Open Access Journals (Sweden)

    Jens A. E. Geginat

    2015-10-01

    Full Text Available Dendritic cells (DC are specialized antigen-presenting cells (APC that have a key role in immune responses, because they bridge the innate and adaptive arms of the immune system. They mature upon recognition of pathogens and up-regulate MHC molecules and co-stimulatory receptors to activate antigen-specific CD4+ and CD8+ T-cells. It is now well established that DC are not a homogeneous population, but are composed of different subsets with specialized functions in immune responses to specific pathogens. Upon viral infections, plasmacytoid DC (pDC rapidly produce large amounts of IFN-α, which has potent anti-viral functions and activates several other immune cells. However, pDC are not particularly potent APC and induce the tolerogenic cytokine IL-10 in CD4+ T-cells. In contrast, myeloid DC (mDC are very potent APC and possess the unique capacity to prime naïve T-cells and consequently to initiate a primary adaptive immune response. Different subsets of myeloid DC with specialized functions have been identified. In mice, CD8α+ mDC capture antigenic material from necrotic cells, secrete high levels of IL-12, and prime Th1 and cytotoxic T cell responses to control intracellular pathogens. Conversely, CD8α- mDC preferentially prime CD4+ T-cells and promote Th2 or Th17 differentiation. BDCA-3+ mDC2 are the human homologue of CD8α+ mDC, since they share the expression of several key molecules, the capacity to cross-present antigens to CD8+ T-cells and to produce IFN-λ. However, although several features of the DC network are conserved between humans and mice, the expression of several relevant toll-like receptors as well as the production of cytokines that regulate T-cell differentiation are different. Intriguingly, recent data suggests specific roles for human DC subsets in immune responses against individual pathogens. The biology of human DC subsets holds the promise to be exploitable in translational medicine, in particular for the

  12. Pathogen receptor discovery with a microfluidic human membrane protein array

    Science.gov (United States)

    Glick, Yair; Ben-Ari, Ya’ara; Drayman, Nir; Pellach, Michal; Neveu, Gregory; Boonyaratanakornkit, Jim; Avrahami, Dorit; Einav, Shirit; Oppenheim, Ariella

    2016-01-01

    The discovery of how a pathogen invades a cell requires one to determine which host cell receptors are exploited. This determination is a challenging problem because the receptor is invariably a membrane protein, which represents an Achilles heel in proteomics. We have developed a universal platform for high-throughput expression and interaction studies of membrane proteins by creating a microfluidic-based comprehensive human membrane protein array (MPA). The MPA is, to our knowledge, the first of its kind and offers a powerful alternative to conventional proteomics by enabling the simultaneous study of 2,100 membrane proteins. We characterized direct interactions of a whole nonenveloped virus (simian virus 40), as well as those of the hepatitis delta enveloped virus large form antigen, with candidate host receptors expressed on the MPA. Selected newly discovered membrane protein–pathogen interactions were validated by conventional methods, demonstrating that the MPA is an important tool for cellular receptor discovery and for understanding pathogen tropism. PMID:27044079

  13. An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes.

    Science.gov (United States)

    Kiwamoto, R; Spenkelink, A; Rietjens, I M C M; Punt, A

    2015-01-01

    Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure-activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment.

  14. Inactivation of hepatitis A virus and norovirus surrogate in suspension and on food-contact surfaces using pulsed UV light (pulsed light inactivation of food-borne viruses).

    Science.gov (United States)

    Jean, Julie; Morales-Rayas, Rocío; Anoman, Marie-Natacha; Lamhoujeb, Safaa

    2011-05-01

    This study was conducted to evaluate the inactivation of murine norovirus (MNV-1) and hepatitis A virus (HAV) by pulsed ultraviolet (UV) light. MNV-1 was used as a model for human norovirus. Viral suspensions of about 10(6) PFU/ml were exposed to pulses of UV light for different times and at different distances in a Xenon Steripulse device (model RS-3000C). Inactivation studies were also carried out on 1-cm(2) stainless steel and polyvinyl chloride disks with 10(5) PFU/ml. Inactivation of MNV-1 and HAV at 10.5 cm from the UV source was greater on inert surfaces than in suspension. The presence of organic matter (fetal bovine serum) reduced the effectiveness of pulsed light both in suspension and on surfaces. However, 2-s treatment in the absence of FBS completely inactivated (5 log reduction) the viral load at different distances tested, whether in suspension (MNV-1) or on disks (MNV-1 and HAV). The same treatment in the presence of fetal bovine serum (5%) allowed a reduction of about 3 log. This study showed that short duration pulses represent an excellent alternative for inactivation of food-borne viruses. This technology could be used to inactivate viruses in drinking water or on food-handling surfaces. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Standardized metadata for human pathogen/vector genomic sequences.

    Directory of Open Access Journals (Sweden)

    Vivien G Dugan

    Full Text Available High throughput sequencing has accelerated the determination of genome sequences for thousands of human infectious disease pathogens and dozens of their vectors. The scale and scope of these data are enabling genotype-phenotype association studies to identify genetic determinants of pathogen virulence and drug/insecticide resistance, and phylogenetic studies to track the origin and spread of disease outbreaks. To maximize the utility of genomic sequences for these purposes, it is essential that metadata about the pathogen/vector isolate characteristics be collected and made available in organized, clear, and consistent formats. Here we report the development of the GSCID/BRC Project and Sample Application Standard, developed by representatives of the Genome Sequencing Centers for Infectious Diseases (GSCIDs, the Bioinformatics Resource Centers (BRCs for Infectious Diseases, and the U.S. National Institute of Allergy and Infectious Diseases (NIAID, part of the National Institutes of Health (NIH, informed by interactions with numerous collaborating scientists. It includes mapping to terms from other data standards initiatives, including the Genomic Standards Consortium's minimal information (MIxS and NCBI's BioSample/BioProjects checklists and the Ontology for Biomedical Investigations (OBI. The standard includes data fields about characteristics of the organism or environmental source of the specimen, spatial-temporal information about the specimen isolation event, phenotypic characteristics of the pathogen/vector isolated, and project leadership and support. By modeling metadata fields into an ontology-based semantic framework and reusing existing ontologies and minimum information checklists, the application standard can be extended to support additional project-specific data fields and integrated with other data represented with comparable standards. The use of this metadata standard by all ongoing and future GSCID sequencing projects will

  16. Drosophila as a genetic model for studying pathogenic human viruses.

    Science.gov (United States)

    Hughes, Tamara T; Allen, Amanda L; Bardin, Joseph E; Christian, Megan N; Daimon, Kansei; Dozier, Kelsey D; Hansen, Caom L; Holcomb, Lisa M; Ahlander, Joseph

    2012-02-05

    Viruses are infectious particles whose viability is dependent on the cells of living organisms, such as bacteria, plants, and animals. It is of great interest to discover how viruses function inside host cells in order to develop therapies to treat virally infected organisms. The fruit fly Drosophila melanogaster is an excellent model system for studying the molecular mechanisms of replication, amplification, and cellular consequences of human viruses. In this review, we describe the advantages of using Drosophila as a model system to study human viruses, and highlight how Drosophila has been used to provide unique insight into the gene function of several pathogenic viruses. We also propose possible directions for future research in this area.

  17. Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

    Directory of Open Access Journals (Sweden)

    Alessandra da Silva Dantas

    2015-02-01

    Full Text Available Candida albicans is a major fungal pathogen of humans, causing approximately 400,000 life-threatening systemic infections world-wide each year in severely immunocompromised patients. An important fungicidal mechanism employed by innate immune cells involves the generation of toxic reactive oxygen species (ROS, such as superoxide and hydrogen peroxide. Consequently, there is much interest in the strategies employed by C. albicans to evade the oxidative killing by macrophages and neutrophils. Our understanding of how C. albicans senses and responds to ROS has significantly increased in recent years. Key findings include the observations that hydrogen peroxide triggers the filamentation of this polymorphic fungus and that a superoxide dismutase enzyme with a novel mode of action is expressed at the cell surface of C. albicans. Furthermore, recent studies have indicated that combinations of the chemical stresses generated by phagocytes can actively prevent C. albicans oxidative stress responses through a mechanism termed the stress pathway interference. In this review, we present an up-date of our current understanding of the role and regulation of oxidative stress responses in this important human fungal pathogen.

  18. Saffold virus, a novel human Cardiovirus with unknown pathogenicity.

    Science.gov (United States)

    Himeda, Toshiki; Ohara, Yoshiro

    2012-02-01

    Although cardioviruses have been thought to mainly infect rodents, a novel human cardiovirus, designated Saffold virus (SAFV), was identified in 2007. SAFV is grouped with Theiler-like rat virus and Theiler's murine encephalomyelitis virus (TMEV) in the species Theilovirus of the genus Cardiovirus of the family Picornaviridae. Eight genotypes of SAFV have now been identified. SAFV has been isolated from nasal and stool specimens from infants presenting with respiratory and gastrointestinal symptoms as well as from children with nonpolio acute flaccid paralysis; however, the relationship of SAFV to this symptomatology remains unclear. Of note, the virus has also been isolated from the cerebrospinal fluid specimens of patients with aseptic meningitis. This finding is of interest since TMEV is known to cause a multiple sclerosis-like syndrome in mice. The involvement of SAFV in various diseases (e.g., respiratory illness, gastrointestinal illness, neurological diseases, and type I diabetes) is presently under investigation. In order to clarify the pathogenicity of SAFV, additional epidemiological studies are required. Furthermore, identification of the SAFV cellular receptor will help establish an animal model for SAFV infection and help clarify the pathogenesis of SAFV-related diseases. In addition, investigation of the tissue-specific expression of the receptor may facilitate development of a novel picornavirus vector, which could be a useful tool in gene therapy for humans. The study of viral factors involved in viral pathogenicity using a reverse genetics technique will also be important.

  19. Active suppression of early immune response in tobacco by the human pathogen Salmonella Typhimurium

    National Research Council Canada - National Science Library

    Shirron, Natali; Yaron, Sima

    2011-01-01

    The persistence of enteric pathogens on plants has been studied extensively, mainly due to the potential hazard of human pathogens such as Salmonella enterica being able to invade and survive in/on plants...

  20. Dietary Fatty Acids and Immune Response to Food-Borne Bacterial Infections

    OpenAIRE

    2013-01-01

    Functional innate and acquired immune responses are required to protect the host from pathogenic bacterial infections. Modulation of host immune functions may have beneficial or deleterious effects on disease outcome. Different types of dietary fatty acids have been shown to have variable effects on bacterial clearance and disease outcome through suppression or activation of immune responses. Therefore, we have chosen to review research across experimental models and food sources on the effec...

  1. Enhanced surveillance on food-borne disease outbreaks: dynamics of cross-contamination in biocidal wash procedure.

    Science.gov (United States)

    Munther, Daniel; Wu, Jianhong

    2013-03-21

    Understanding the geographic and temporal spread of food-borne diseases associated with fresh produce is crucial for informing adequate surveillance and control. As a first step towards this goal, we develop and analyze a novel three stage model at the processing/sanitization juncture in the fresh produce supply chain. The key feature of our model is its ability to describe the dynamics of cross-contamination during commercial wash procedures. In general, we quantify the degree of cross-contamination in terms of model parameters. Applying these results in the case of Escherichia coli O157:H7 contamination of fresh-cut romaine lettuce, we identify the mean wash time and free chlorine concentration as critical parameters. In addition to showing how these parameters affect contamination levels, we recommend that in order to prevent potential source misidentification, at least 2.2 mg/L of free chlorine should be used during a wash lasting at least 30s.

  2. Extraintestinal Pathogenic Escherichia coli, a Common Human Pathogen: Challenges for Vaccine Development and Progress in the Field

    OpenAIRE

    2015-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) is the most common gram-negative bacterial pathogen in humans. ExPEC causes the vast majority of urinary tract infections (UTIs), is a leading cause of adult bacteremia, and is the second most common cause of neonatal meningitis. Increasing multidrug resistance among ExPEC strains constitutes a major obstacle to treatment and is implicated in increasing numbers of hospitalizations and deaths and increasing healthcare costs associated with Ex...

  3. The graphene oxide contradictory effects against human pathogens

    Science.gov (United States)

    Palmieri, Valentina; Carmela Lauriola, Maria; Ciasca, Gabriele; Conti, Claudio; De Spirito, Marco; Papi, Massimiliano

    2017-04-01

    Standing out as the new wonder bidimensional material, graphene oxide (GO) has aroused an exceptional interest in biomedical research by holding promise for being the antibacterial of future. First, GO possesses a specific interaction with microorganisms combined with a mild toxicity for human cells. Additionally, its antibacterial action seems to be directed to multiple targets in pathogens, causing both membranes mechanical injury and oxidative stress. Lastly, compared to other carbon materials, GO has easy and low-cost processing and is environment-friendly. This remarkable specificity and multi-targeting antibacterial activity come at a time when antibiotic resistance represents the major health challenge. Unfortunately, a comprehensive framework to understand how to effectively utilize this material against microorganisms is still lacking. In the last decade, several groups tried to define the mechanisms of interaction between GO flakes and pathogens but conflicting results have been reported. This review is focused on all the contradictions of GO antimicrobial properties in solution. Flake size, incubation protocol, time of exposure and species considered are examples of factors influencing results. These parameters will be summarized and analyzed with the aim of defining the causes of contradictions, to allow fast GO clinical application.

  4. Rickettsia felis, an emerging flea-transmitted human pathogen

    Directory of Open Access Journals (Sweden)

    Stephen Graves

    2011-07-01

    Full Text Available Rickettsia felis was first recognised two decades ago and has now been described as endemic to all continents except Antarctica. The rickettsiosis caused by R. felis is known as flea-borne spotted fever or cat-flea typhus. The large number of arthropod species found to harbour R. felis and that may act as potential vectors support the view that it is a pan-global microbe. The main arthropod reservoir and vector is the cat flea, Ctenocephalides felis, yet more than 20 other species of fleas, ticks, and mites species have been reported to harbour R. felis. Few bacterial pathogens of humans have been found associated with such a diverse range of invertebrates. With the projected increase in global temperature over the next century, there is concern that changes to the ecology and distribution of R. felis vectors may adversely impact public health.

  5. Host cell modulation by human, animal and plant pathogens.

    Science.gov (United States)

    Andersson, Siv G E; Kempf, Volkhard A J

    2004-04-01

    Members of the alpha-proteobacteria display a broad range of interactions with higher eukaryotes. Some are pathogens of humans, such as Rickettsia and Bartonella that are associated with diseases like epidemic typhus, trench fever, cat scratch disease and bacillary angiomatosis. Others like the Brucella cause abortions in pregnant animals. Yet other species have evolved elaborate interactions with plants; in this group we find both plant symbionts and parasites. Despite radically different host preferences, extreme genome size variations and the absence of toxin genes, similarities in survival strategies and host cell interactions can be recognized among members of the alpha-proteobacteria. Here, we review some of these similarities, with a focus on strategies for modulation of the host target cell.

  6. Fate of pathogenic bacteria in microcosms mimicking human body sites.

    Science.gov (United States)

    Castellani, Francesco; Ghidini, Valentina; Tafi, Maria Carla; Boaretti, Marzia; Lleo, Maria M

    2013-07-01

    During the infectious process, pathogens may reach anatomical sites where they are exposed to substances interfering with their growth. These substances can include molecules produced by the host, and his resident microbial population, as well as exogenous antibacterial drugs. Suboptimal concentrations of inhibitory molecules and stress conditions found in vivo (high or low temperatures, lack of oxygen, extreme pH) might induce in bacteria the activation of survival mechanisms blocking their division capability but allowing them to stay alive. These "dormant" bacteria can be reactivated in particular circumstances and would be able to express their virulence traits. In this study, it was evaluated the effect of some environmental conditions, such as optimal and suboptimal temperatures, direct light and antibiotic sub-inhibitory concentrations doses of antibiotic, on the human pathogens Escherichia coli and Enterococcus faecalis when incubated in fluids accumulated in the body of patients with different pathologies. It is shown that inoculation in a number of accumulated body fluids and the presence of gentamicin, reliable conditions encountered during pathological states, induce stress-responding strategies enabling bacteria to persist in microcosms mimicking the human body. Significant differences were detected in Gram-negative and Gram-positive species with E. faecalis surviving, as starved or viable but non-culturable forms, in any microcosm and condition tested and E. coli activating a viable but non-culturable state only in some clinical samples. The persistence of bacteria under these conditions, being non-culturable, might explain some recurrent infections without isolation of the causative agent after application of the standard microbiological methods.

  7. A Quantitative Prioritisation of Human and Domestic Animal Pathogens in Europe

    Science.gov (United States)

    McIntyre, K. Marie; Setzkorn, Christian; Hepworth, Philip J.; Morand, Serge; Morse, Andrew P.; Baylis, Matthew

    2014-01-01

    Disease or pathogen risk prioritisations aid understanding of infectious agent impact within surveillance or mitigation and biosecurity work, but take significant development. Previous work has shown the H-(Hirsch-)index as an alternative proxy. We present a weighted risk analysis describing infectious pathogen impact for human health (human pathogens) and well-being (domestic animal pathogens) using an objective, evidence-based, repeatable approach; the H-index. This study established the highest H-index European pathogens. Commonalities amongst pathogens not included in previous surveillance or risk analyses were examined. Differences between host types (humans/animals/zoonotic) in pathogen H-indices were explored as a One Health impact indicator. Finally, the acceptability of the H-index proxy for animal pathogen impact was examined by comparison with other measures. 57 pathogens appeared solely in the top 100 highest H-indices (1) human or (2) animal pathogens list, and 43 occurred in both. Of human pathogens, 66 were zoonotic and 67 were emerging, compared to 67 and 57 for animals. There were statistically significant differences between H-indices for host types (humans, animal, zoonotic), and there was limited evidence that H-indices are a reasonable proxy for animal pathogen impact. This work addresses measures outlined by the European Commission to strengthen climate change resilience and biosecurity for infectious diseases. The results include a quantitative evaluation of infectious pathogen impact, and suggest greater impacts of human-only compared to zoonotic pathogens or scientific under-representation of zoonoses. The outputs separate high and low impact pathogens, and should be combined with other risk assessment methods relying on expert opinion or qualitative data for priority setting, or could be used to prioritise diseases for which formal risk assessments are not possible because of data gaps. PMID:25136810

  8. Evolution and Emergence of Pathogenic Viruses: Past, Present, and Future.

    Science.gov (United States)

    Parvez, Mohammad K; Parveen, Shama

    2017-01-01

    Incidences of emerging/re-emerging deadly viral infections have significantly affected human health despite extraordinary progress in the area of biomedical knowledge. The best examples are the recurring outbreaks of dengue and chikungunya fever in tropical and sub-tropical regions, the recent epidemic of Zika in the Americas and the Caribbean, and the SARS, MERS, and influenza A outbreaks across the globe. The established natural reservoirs of human viruses are mainly farm animals, and, to a lesser extent, wild animals and arthropods. The intricate "host-pathogen-environment" relationship remains the key to understanding the emergence/re-emergence of pathogenic viruses. High population density, rampant constructions, poor sanitation, changing climate, and the introduction of anthropophilic vectors create selective pressure on host-pathogen reservoirs. Nevertheless, the knowledge and understanding of such zoonoses and pathogen diversity in their known non-human reservoirs are very limited. Prevention of arboviral infections using vector control methods has not been very successful. Currently, new approaches to protect against food-borne infections, such as consuming only properly cooked meats and animal products, are the most effective control measures. Though significant progress in controlling human immunodeficiency virus and hepatitis viruses has been achieved, the unpredictable nature of evolving viruses and the rare occasions of outbreaks severely hamper control and preventive modalities. © 2017 S. Karger AG, Basel.

  9. The landscape of human proteins interacting with viruses and other pathogens.

    Directory of Open Access Journals (Sweden)

    Matthew D Dyer

    2008-02-01

    Full Text Available Infectious diseases result in millions of deaths each year. Mechanisms of infection have been studied in detail for many pathogens. However, many questions are relatively unexplored. What are the properties of human proteins that interact with pathogens? Do pathogens interact with certain functional classes of human proteins? Which infection mechanisms and pathways are commonly triggered by multiple pathogens? In this paper, to our knowledge, we provide the first study of the landscape of human proteins interacting with pathogens. We integrate human-pathogen protein-protein interactions (PPIs for 190 pathogen strains from seven public databases. Nearly all of the 10,477 human-pathogen PPIs are for viral systems (98.3%, with the majority belonging to the human-HIV system (77.9%. We find that both viral and bacterial pathogens tend to interact with hubs (proteins with many interacting partners and bottlenecks (proteins that are central to many paths in the network in the human PPI network. We construct separate sets of human proteins interacting with bacterial pathogens, viral pathogens, and those interacting with multiple bacteria and with multiple viruses. Gene Ontology functions enriched in these sets reveal a number of processes, such as cell cycle regulation, nuclear transport, and immune response that participate in interactions with different pathogens. Our results provide the first global view of strategies used by pathogens to subvert human cellular processes and infect human cells. Supplementary data accompanying this paper is available at http://staff.vbi.vt.edu/dyermd/publications/dyer2008a.html.

  10. Draft genome sequence of the first human isolate of the ruminant pathogen Mycoplasma capricolum subsp. capricolum

    DEFF Research Database (Denmark)

    Seersholm, Frederik Valeur; Fischer, Anne; Heller, Martin

    2015-01-01

    Mycoplasma capricolum subsp. capricolum is a well-known pathogen of small ruminants. A recent human case of septicemia involving this agent raised the question of its potential pathogenicity to humans. We present the first draft genome sequence of a human Mycoplasma capricolum subsp. capricolum...

  11. Ecophysiological characterization of common food-borne fungi in relation to pH and water activity under various atmospheric compositions

    DEFF Research Database (Denmark)

    Haasum, Iben; Nielsen, Per Væggemose

    1998-01-01

    The combined effect of pH, water activity (aw), oxygen (O2) and carbon dioxide (CO2) levels on growth and sporulation of 10 common food-borne fungi were studied. The use of a multivariate statistical method (PLS) for the analysis of data showed, that the fungi could be grouped according...

  12. Study in vitro of origin radioprotective food the radioprotective effect in vitro of food borne; Estudio in vitro de radioprotectores de origen alimentario

    Energy Technology Data Exchange (ETDEWEB)

    Soraino, J. M.; Sebastia, N.; Almonacid, M.; Alonso, O.; Cervera, J.; Such, E.; Silla, M. A.; Villaescusa, J. I.; Montoro, A.

    2012-07-01

    Study in vitro of origin radioprotective food the radioprotective effect in vitro of food borne substances studied is a first step in developing effective radioprotectors that can prevent radiation damage to healthy tissue., cannot forget that these studies must be accompanied by in vitro studies of toxicity and bioavailability to profile designing radioprotective substance.

  13. Detection of Kudoa septempunctata 18S ribosomal DNA in patient fecal samples from novel food-borne outbreaks caused by consumption of raw olive flounder (Paralichthys olivaceus).

    Science.gov (United States)

    Harada, Tetsuya; Kawai, Takao; Jinnai, Michio; Ohnishi, Takahiro; Sugita-Konishi, Yoshiko; Kumeda, Yuko

    2012-09-01

    Kudoa septempunctata is a newly identified myxosporean parasite of olive flounder (Paralichthys olivaceus) and a suspected causative agent of several food-borne gastroenteritis outbreaks in Japan. Here, we report the detection of K. septempunctata 18S ribosomal DNA in fecal samples of outbreak patients using an efficient method based on real-time PCR. We first performed a spiking experiment to assess whether our previously developed real-time PCR assay was applicable to detect K. septempunctata in feces. Simultaneously, we compared the relative extraction efficacy of K. septempunctata DNA using three commercial kits. Finally, our detection method was validated by testing 45 clinical samples obtained from 13 food-borne outbreaks associated with the consumption of raw flounder and 41 fecal samples from diarrhea patients epidemiologically unrelated to the ingestion of raw fish. We found that the FastDNA Spin Kit for Soil (MP Biomedicals) was the most efficient method for extracting K. septempunctata DNA from fecal samples. Using this kit, the detection limit of our real-time PCR assay was 1.6 × 10(1) spores per g of feces, and positive results were obtained for 21 fecal and 2 vomitus samples obtained from the food-borne outbreaks. To our knowledge, this is the first report to describe the detection of K. septempunctata DNA in patient fecal samples. We anticipate that our detection method will be useful for confirming food-borne diseases caused by K. septempunctata in laboratory investigations.

  14. Matrix-derived combination effects influencing absorption, distribution, metabolism and excretion (ADME) of food-borne toxic compounds: implications for risk assessment

    NARCIS (Netherlands)

    Rietjens, I.; Tyrakowska, B.; Berg, van den S.J.P.L.; Soffers, A.E.M.F.; Punt, A.

    2015-01-01

    Absorption, distribution, metabolism and excretion (ADME) of food-borne toxic compounds may be influenced by other compounds or constituents present in the food. The present review presents an overview of evidence currently available on food matrix-derived combination effects influencing the ADME ch

  15. Parasite Mitogen-Activated Protein Kinases as Drug Discovery Targets to Treat Human Protozoan Pathogens

    Directory of Open Access Journals (Sweden)

    Michael J. Brumlik

    2011-01-01

    Full Text Available Protozoan pathogens are a highly diverse group of unicellular organisms, several of which are significant human pathogens. One group of protozoan pathogens includes obligate intracellular parasites such as agents of malaria, leishmaniasis, babesiosis, and toxoplasmosis. The other group includes extracellular pathogens such as agents of giardiasis and amebiasis. An unfortunate unifying theme for most human protozoan pathogens is that highly effective treatments for them are generally lacking. We will review targeting protozoan mitogen-activated protein kinases (MAPKs as a novel drug discovery approach towards developing better therapies, focusing on Plasmodia, Leishmania, and Toxoplasma, about which the most is known.

  16. THE IMPORTANCE AND INCIDENCE OF FOOD BORN HELMINTH INFECTIONS IN MAN, IN IRAN

    Directory of Open Access Journals (Sweden)

    H.A. Neshat

    1976-08-01

    Full Text Available A wide variety of helminth parasite, which is quite prevalent in Iran, can infect man by the oral route. The main sources of infections are meat, vegetables and water. Some of these parasites, e.g. Cysticercus bovis, C. cellulose, Trichinella spairalis and Anisakis larvae, are present in the tissue of food animal. Human infection establish by consuming raw or inadequately cooked pork, beef or fish. The infective stages of some helminths, e.g. Trichostrongylus spp., Ascaris lumbricoides, Trichuris trichura, Fasciola spp. Dicrocelium dendriticum and Dracuncwlus medinensis may infect man through vegetable and drinking water. Using human and animal manure as fertilizer of the soil, facilitate the transmission of these parasites to man. Contaminated food materials can pay also a role in, human hydatidosis. Hygiene is a key factor in the control of all conditions and both medical and veterinary professions have an important function in this field.

  17. Antimicrobial properties of marine seaweed, Sargassum muticum against human pathogens

    Institute of Scientific and Technical Information of China (English)

    Puthamohan Vinayaga Moorthi; Chelliah Balasubramanian

    2015-01-01

    Objective:To evaluate the antibacterial efficiency of the seaweed, Sargassum muticum (S. muticum) collected from Pudumadam, Ramanathapuram, Tamil Nadu, India. Methods:Crude solvent extracts of S. muticum were obtained by using Soxhlet extraction and the solvents like acetone, methanol and chloroform. These different extracts were tested against different human bacterial pathogens such as Micrococcus sp., Staphylococcus aureus (methicillin resistance), Salmonella paratyphi B, Staphylococcus epidermis (3615), Enterobacter aerogenus (111), Klebsiella pneumonia (109), Shigella fleschneri (1457) (S. fleschneri), Proteus vulgaris (1771), Staphylococcus aureus (96) and Salmonella typhymurium (SP7) which were obtained from Microbial Type Culture Collection, Indian Institute of Microbial Technology, Chandigarh, India. Results:The results revealed that acetone extract had unveiled the maximum of 11 mm zone of inhibition at 40 µL against S. fleschneri. Similar zone of inhibition (11 mm) was also observed at 50 µL against Micrococcus sp. and S. fleschneri. Followed by acetone extract, chloroform extract also contributed 11 mm zone of inhibition against S. fleschneri and Salmonella paratyphi B at 40 and 50 µL respectively. Besides, methanol extracts revealed meager antibacterial activity (9 mm). Conclusions:The present investigation suggests that the phytochemical constituent of the S. muticum might be suitable agents for the control of human deadly diseases.

  18. Genetic diversity and population structure of food-borne Staphylococcus carnosus strains.

    Science.gov (United States)

    Bückle Née Müller, Anne; Kranz, Markus; Schmidt, Herbert; Weiss, Agnes

    2017-01-01

    The species Staphylococcus carnosus is a non-pathogenic representative of the coagulase negative staphylococci. Specific strains are applied as meat starter cultures. The species consists of two subspecies, S. carnosus ssp. carnosus and S. carnosus ssp. utilis. In order to place S. carnosus strains, characterized in former studies, in a genetic background that allows a typing of candidates for starter cultures, a Multilocus Sequence Typing (MLST) scheme was developed. Internal fragments of the genes tpiA, xprT, dat, gmk, glpK, narG, cstA, encoding triosephosphate isomerase, xanthine phosphoribosyltransferase, d-amino acid aminotransferase, guanylate kinase, glycerol kinase, the α-chain of the respiratory nitrate reductase, and a carbon starvation protein where chosen. Genes were selected based on their equal distribution in the genome, taxonomic value in subspecies differentiation and metabolic function. This MLST was applied to 44 S. carnosus strains, most of them previously analyzed for their suitability as starter cultures. The number of alleles varied between zero (tpiA) and five (cstA) and allowed the definition of nine sequence types (ST). ST1 was most abundant (18 strains), followed by ST2 (8) and ST4 (6). The nine STs confirmed a close relationship of all strains despite their isolation source and year, but lacked correlation with physiological activities relevant for starter cultures. The low amount of STs in the strain set lets us suggest that recombination between strains is rare. Thus, it is hypothesized that evolutionary events seem to be due to single point mutations rather than intrachromosomal recombination, and that the species possesses a clonal population structure. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. An integrated QSAR-PBK/D modelling approach for predicting detoxification and DNA adduct formation of 18 acyclic food-borne α,β-unsaturated aldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Kiwamoto, R., E-mail: reiko.kiwamoto@wur.nl; Spenkelink, A.; Rietjens, I.M.C.M.; Punt, A.

    2015-01-01

    Acyclic α,β-unsaturated aldehydes present in food raise a concern because the α,β-unsaturated aldehyde moiety is considered a structural alert for genotoxicity. However, controversy remains on whether in vivo at realistic dietary exposure DNA adduct formation is significant. The aim of the present study was to develop physiologically based kinetic/dynamic (PBK/D) models to examine dose-dependent detoxification and DNA adduct formation of a group of 18 food-borne acyclic α,β-unsaturated aldehydes without 2- or 3-alkylation, and with no more than one conjugated double bond. Parameters for the PBK/D models were obtained using quantitative structure–activity relationships (QSARs) defined with a training set of six selected aldehydes. Using the QSARs, PBK/D models for the other 12 aldehydes were defined. Results revealed that DNA adduct formation in the liver increases with decreasing bulkiness of the molecule especially due to less efficient detoxification. 2-Propenal (acrolein) was identified to induce the highest DNA adduct levels. At realistic dietary intake, the predicted DNA adduct levels for all aldehydes were two orders of magnitude lower than endogenous background levels observed in disease free human liver, suggesting that for all 18 aldehydes DNA adduct formation is negligible at the relevant levels of dietary intake. The present study provides a proof of principle for the use of QSAR-based PBK/D modelling to facilitate group evaluations and read-across in risk assessment. - Highlights: • Physiologically based in silico models were made for 18 α,β-unsaturated aldehydes. • Kinetic parameters were determined by in vitro incubations and a QSAR approach. • DNA adduct formation was negligible at levels relevant for dietary intake. • The use of QSAR-based PBK/D modelling facilitates group evaluations and read-across.

  20. Cytotoxic and genotoxic potential of food-borne nitriles in a liver in vitro model

    OpenAIRE

    Franziska Kupke; Corinna Herz; Hanschen, Franziska S.; Stefanie Platz; Grace A. Odongo; Simone Helmig; Bartolomé Rodríguez, María M.; Monika Schreiner; Sascha Rohn; Evelyn Lamy

    2016-01-01

    Isothiocyanates are the most intensively studied breakdown products of glucosinolates from Brassica plants and well recognized for their pleiotropic effects against cancer but also for their genotoxic potential. However, knowledge about the bioactivity of glucosinolate-borne nitriles in foods is very poor. As determined by GC-MS, broccoli glucosinolates mainly degrade to nitriles as breakdown products. The cytotoxicity of nitriles in human HepG2 cells and primary murine hepatocytes was margin...

  1. The human-bacterial pathogen protein interaction networks of Bacillus anthracis, Francisella tularensis, and Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Matthew D Dyer

    Full Text Available BACKGROUND: Bacillus anthracis, Francisella tularensis, and Yersinia pestis are bacterial pathogens that can cause anthrax, lethal acute pneumonic disease, and bubonic plague, respectively, and are listed as NIAID Category A priority pathogens for possible use as biological weapons. However, the interactions between human proteins and proteins in these bacteria remain poorly characterized leading to an incomplete understanding of their pathogenesis and mechanisms of immune evasion. METHODOLOGY: In this study, we used a high-throughput yeast two-hybrid assay to identify physical interactions between human proteins and proteins from each of these three pathogens. From more than 250,000 screens performed, we identified 3,073 human-B. anthracis, 1,383 human-F. tularensis, and 4,059 human-Y. pestis protein-protein interactions including interactions involving 304 B. anthracis, 52 F. tularensis, and 330 Y. pestis proteins that are uncharacterized. Computational analysis revealed that pathogen proteins preferentially interact with human proteins that are hubs and bottlenecks in the human PPI network. In addition, we computed modules of human-pathogen PPIs that are conserved amongst the three networks. Functionally, such conserved modules reveal commonalities between how the different pathogens interact with crucial host pathways involved in inflammation and immunity. SIGNIFICANCE: These data constitute the first extensive protein interaction networks constructed for bacterial pathogens and their human hosts. This study provides novel insights into host-pathogen interactions.

  2. New trends in emerging pathogens.

    Science.gov (United States)

    Skovgaard, Niels

    2007-12-15

    The emergence of pathogens is the result of a number of impact in all parts of the food chain. The emerging technologies in food production explain how new pathogens can establish themselves in the food chain and compromise food safety. The impact of the food technology is analysed for several bacteria, such as Yersinia, Campylobacter, Arcobacter, Helicobacter pullorum, Enterobacter sakazakii, Mycobacterium avium spp. paratuberculosis, prions related to vCJD and others. The importance of the ability of many microbes to form VBNC forms is elaborated on. Research on culture independent methods may address this outstanding issue to the better understanding of emerging pathogens. The "demerging" of pathogens also occur, and examples of this are explained. The reaction of bacteria to stresses and sublethal treatments, and how exposure to one stress factor can confer resistance to other stresses, literally speaking causing contagious resistance, are explained. The implication of this e.g. in modern approaches of food preservation, such as Minimally processed Foods, is considerable. Intestinal colonization of EHEC may be regulated by Quorum sensing, and this ability of microbes plays an important role in the colonization of microbes in food and on food processing equipment, an important factor in the emergence of pathogens. The emergence of Saccharomyces cerevisiae, as an opportunistic human pathogen, used for centuries for food and production of alcoholic beverages, calls for research in molecular tools to distinguish between probiotic and clinical strains. Cyclospora cayetanensis and Norovirus outbreaks can no longer be designated as emerging pathogens, they share however one characteristic in the epidemiology of emerging nature, the importance of the hygiene in the primary production stage, including supply of potable water, and the application of GMP and the HACCP principles in the beginning of the food chain. Hepatitis E virus is a potential emerging food borne

  3. Salmonella, a cross-kingdom pathogen infecting humans and plants.

    Science.gov (United States)

    Hernández-Reyes, Casandra; Schikora, Adam

    2013-06-01

    Infections with non-typhoidal Salmonella strains are constant and are a non-negligible threat to the human population. In the last two decades, salmonellosis outbreaks have increasingly been associated with infected fruits and vegetables. For a long time, Salmonellae were assumed to survive on plants after a more or less accidental infection. However, this notion has recently been challenged. Studies on the infection mechanism in vegetal hosts, as well as on plant immune systems, revealed an active infection process resembling in certain features the infection in animals. On one hand, Salmonella requires the type III secretion systems to effectively infect plants and to suppress their resistance mechanisms. On the other hand, plants recognize these bacteria and react to the infection with an induced defense mechanism similar to the reaction to other plant pathogens. In this review, we present the newest reports on the interaction between Salmonellae and plants. We discuss the possible ways used by these bacteria to infect plants as well as the plant responses to the infection. The recent findings indicate that plants play a central role in the dissemination of Salmonella within the ecosystem.

  4. In Silico Prediction of Human Pathogenicity in the gamma-Proteobacteria

    DEFF Research Database (Denmark)

    Andreatta, Massimo; Nielsen, Morten; Aarestrup, Frank Møller

    2010-01-01

    strongly needed to mine the fast growing number of genome sequences and assess in a rapid and reliable way the pathogenicity of novel bacteria. Methodology/Principal Findings: We describe a new in silico method for the prediction of bacterial pathogenicity, based on the identification in microbial genomes...... to be able to separate pathogenic organisms from non-pathogenic ones. Using traditional experimental methods for this purpose can be very costly and time-consuming, and also uncertain since animal models are not always good predictors for pathogenicity in humans. Bioinformatics-based methods are therefore....... A set of protein families that differentiate pathogenic and non-pathogenic strains were identified, including families of yet uncharacterized proteins that are suggested to be involved in bacterial pathogenicity....

  5. The effects of antibiotic usage in food animals on the development of antimicrobial resistance of importance for humans in Campylobacter and Escherichia coli

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Wegener, Henrik Caspar

    1999-01-01

    Modern food animal production depends on use of large amounts of antibiotics for disease control. This provides favourable conditions for the spread and persistence of antimicrobial-resistant zoonotic bacteria such as Campylobacter and E. coli O157. The occurrence of antimicrobial resistance...... to antimicrobials used in human therapy is increasing in human pathogenic Campylobacter and E. coli from animals. There is an urgent need to implement strategies for prudent use of antibiotics in food animal production to prevent further increases in the occurrence of antimicrobial resistance in food-borne human...

  6. An unclassified microorganism: novel pathogen candidate lurking in human airways.

    Directory of Open Access Journals (Sweden)

    Kazumasa Fukuda

    Full Text Available During the assessments of the correlation of the diseases and the microbiota of various clinical specimens, unique 16S ribosomal RNA (rRNA gene sequences (less than 80% similarity to known bacterial type strains were predominantly detected in a bronchoalveolar lavage fluid (BALF specimen from a patient with chronic lower respiratory tract infection. The origin of this unique sequence is suspected to be the causative agent of the infection. We temporarily named the owner organism of this sequence "IOLA" (Infectious Organism Lurking in Airways. In order to evaluate the significance of IOLA in human lung disorders, we performed several experiments. IOLA-16S rRNA genes were detected in 6 of 386 clone libraries constructed from clinical specimens of patients with respiratory diseases (in our study series. The gene sequences (1,427 bp are identical, and no significantly similar sequence was found in public databases (using NCBI blastn except for the 8 shorter sequences detected from patients with respiratory diseases in other studies from 2 other countries. Phylogenetic analyses revealed that the 16S rRNA gene of IOLA is more closely related to eukaryotic mitochondria than bacteria. However, the size and shape of IOLA seen by fluorescent in-situ hybridization are similar to small bacteria (approximately 1 µm with a spherical shape. Furthermore, features of both bacteria and mitochondria were observed in the genomic fragment (about 19 kb of IOLA, and the GC ratio of the sequence was extremely low (20.5%. Two main conclusions were reached: (1 IOLA is a novel bacteria-like microorganism that, interestingly, possesses features of eukaryotic mitochondria. (2 IOLA is a novel pathogen candidate, and it may be the causative agent of human lung or airway disease. IOLA exists in BALF specimens from patients with remarkable symptoms; this information is an important piece for helping solve the elusive etiology of chronic respiratory disorders.

  7. 食源性寄生虫病的防治%Prevention and treatment of food borne parasitic diseases

    Institute of Scientific and Technical Information of China (English)

    许炽熛

    2007-01-01

    食源性寄生虫病(food borne parasitic diseases)是指通过吃了食物中所携带的寄生虫体或幼虫而受感染的寄生虫病,其范围很广,可包括:原虫病、蠕虫病及节肢动物病。随着我国改革开放政策的深入发展,我国经济形势大好,人民生活水平及条件得到明显提高和改善,寄生虫病的种类也发生了改变,土源性寄生虫病的发病率逐渐下降,而食源性寄生虫病的发病率却呈日渐增多的趋势,一些过去较少见的食源性寄生虫病,如鄂口线虫病、肾膨结线虫病、广州管圆线虫病等也比以前多见。过去在山区才能吃到小螃蟹(溪蟹等),现在已运到城市饭店内销售,因而,

  8. International linkage of two food-borne hepatitis A clusters through traceback of mussels, the Netherlands, 2012.

    Science.gov (United States)

    Boxman, Ingeborg L A; Verhoef, Linda; Vennema, Harry; Ngui, Siew-Lin; Friesema, Ingrid H M; Whiteside, Chris; Lees, David; Koopmans, Marion

    2016-01-01

    This report describes an outbreak investigation starting with two closely related suspected food-borne clusters of Dutch hepatitis A cases, nine primary cases in total, with an unknown source in the Netherlands. The hepatitis A virus (HAV) genotype IA sequences of both clusters were highly similar (459/460 nt) and were not reported earlier. Food questionnaires and a case-control study revealed an association with consumption of mussels. Analysis of mussel supply chains identified the most likely production area. International enquiries led to identification of a cluster of patients near this production area with identical HAV sequences with onsets predating the first Dutch cluster of cases. The most likely source for this cluster was a case who returned from an endemic area in Central America, and a subsequent household cluster from which treated domestic sewage was discharged into the suspected mussel production area. Notably, mussels from this area were also consumed by a separate case in the United Kingdom sharing an identical strain with the second Dutch cluster. In conclusion, a small number of patients in a non-endemic area led to geographically dispersed hepatitis A outbreaks with food as vehicle. This link would have gone unnoticed without sequence analyses and international collaboration.

  9. Methods for detecting pathogens in the food chain for beef: from farm to slaughter

    Science.gov (United States)

    The main food-borne pathogens of concern in the beef chain are Shiga toxin-producing Escherichia coli (STEC) and Salmonella. Other pathogens, including Listeria monocytogenes and Campylobacter spp. may also be present and pose contamination concerns in both the cattle production environment and bee...

  10. Iron acquisition functions expressed by the human pathogen Acinetobacter baumannii.

    Science.gov (United States)

    Zimbler, Daniel L; Penwell, William F; Gaddy, Jennifer A; Menke, Sharon M; Tomaras, Andrew P; Connerly, Pamela L; Actis, Luis A

    2009-02-01

    Acinetobacter baumannii is a gram-negative bacterium that causes serious infections in compromised patients. More recently, it has emerged as the causative agent of severe infections in military personnel wounded in Iraq and Afghanistan. This pathogen grows under a wide range of conditions including iron-limiting conditions imposed by natural and synthetic iron chelators. Initial studies using the type strain 19606 showed that the iron proficiency of this pathogen depends on the expression of the acinetobactin-mediated iron acquisition system. More recently, we have observed that hemin but not human hemoglobin serves as an iron source when 19606 isogenic derivatives affected in acinetobactin transport and biosynthesis were cultured under iron-limiting conditions. This finding is in agreement with the observation that the genome of the strain 17978 has a gene cluster coding for putative hemin-acquisition functions, which include genes coding for putative hemin utilization functions and a TonBExbBD energy transducing system. This system restored enterobactin biosynthesis in an E. coli ExbBD deficient strain but not when introduced into a TonB mutant. PCR and Southern blot analyses showed that this hemin-utilization gene cluster is also present in the 19606 strain. Analysis of the 17978 genome also showed that this strain harbors genes required for acinetobactin synthesis and transport as well as a gene cluster that could code for additional iron acquisition functions. This hypothesis is in agreement with the fact that the inactivation of the basD acinetobactin biosynthetic gene did not affect the growth of A. baumannii 17978 cells under iron-chelated conditions. Interestingly, this second iron uptake gene cluster is flanked by perfect inverted repeats and includes transposase genes that are expressed transcriptionally. Also interesting is the observation that this additional cluster could not be detected in the type strain 19606, an observation that suggests some

  11. Antagonistic activity of antibiotic producing Streptomyces sp. against fish and human pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Nazmul Hossain

    2014-04-01

    Full Text Available In this study, attempts were made to isolate Streptomyces sp. from soil samples of two different regions of Bangladesh and evaluate their antagonistic activity against fish and human pathogenic bacteria. A total of 10 isolates were identified as Streptomyces sp. based on several morphological, physiological and biochemical tests. Cross streak method was used to observe the antagonistic activity of the Streptomyces sp. isolates against different fish pathogens belonging to the genus Aeromonas, Pseudomonas and Edwardsiella and human clinical isolates belonging to the genus Klebsiella, Salmonella and Streptococcus. Seven Streptomyces sp. isolates showed antagonism against both fish and human pathogenic bacteria. Four isolates viz., N24, N26, N28 and N47 showed broad spectrum of antagonistic activity (80-100% against all genera of fish and human pathogenic bacteria. The isolate N49 exhibited highest spectrum of antagonism against all fish pathogens (90-100% but comparatively lower degree of antagonism against human pathogens (50-60%. Rest of the two isolates (N21 and N23 showed variability in their antagonism. Results showed that broad spectrum antibiotic(s could be developed from the isolates N24, N26, N28 and N47against several human and fish pathogens. The isolate N49 could be a potential source of antibiotic, especially for fish pathogenic bacteria.

  12. The rhizosphere microbiome: significance of plant beneficial, plant pathogenic and human pathogenic microorganisms

    NARCIS (Netherlands)

    Mendes, R.; Garbeva, P.; Raaijmakers, J.M.

    2013-01-01

    Microbial communities play a pivotal role in the functioning of plants by influencing their physiology and development. While many members of the rhizosphere microbiome are beneficial to plant growth, also plant pathogenic microorganisms colonize the rhizosphere striving to break through the protect

  13. The rhizosphere microbiome: significance of plant beneficial, plant pathogenic and human pathogenic microorganisms

    NARCIS (Netherlands)

    Mendes, R.; Garbeva, P.; Raaijmakers, J.M.

    2013-01-01

    Microbial communities play a pivotal role in the functioning of plants by influencing their physiology and development. While many members of the rhizosphere microbiome are beneficial to plant growth, also plant pathogenic microorganisms colonize the rhizosphere striving to break through the protect

  14. The rhizosphere microbiome: significance of plant beneficial, plant pathogenic, and human pathogenic microorganisms

    NARCIS (Netherlands)

    Mendes, R.; Garbeva, P.V.; Raaijmakers, J.M.

    2013-01-01

    Microbial communities play a pivotal role in the functioning of plants by influencing their physiology and development. While many members of the rhizosphere microbiome are beneficial to plant growth, also plant pathogenic microorganisms colonize the rhizosphere striving to break through the protect

  15. Developmental gene expression profiles of the human pathogen Schistosoma japonicum

    Science.gov (United States)

    Gobert, Geoffrey N; Moertel, Luke; Brindley, Paul J; McManus, Donald P

    2009-01-01

    Background The schistosome blood flukes are complex trematodes and cause a chronic parasitic disease of significant public health importance worldwide, schistosomiasis. Their life cycle is characterised by distinct parasitic and free-living phases involving mammalian and snail hosts and freshwater. Microarray analysis was used to profile developmental gene expression in the Asian species, Schistosoma japonicum. Total RNAs were isolated from the three distinct environmental phases of the lifecycle – aquatic/snail (eggs, miracidia, sporocysts, cercariae), juvenile (lung schistosomula and paired but pre-egg laying adults) and adult (paired, mature males and egg-producing females, both examined separately). Advanced analyses including ANOVA, principal component analysis, and hierarchal clustering provided a global synopsis of gene expression relationships among the different developmental stages of the schistosome parasite. Results Gene expression profiles were linked to the major environmental settings through which the developmental stages of the fluke have to adapt during the course of its life cycle. Gene ontologies of the differentially expressed genes revealed a wide range of functions and processes. In addition, stage-specific, differentially expressed genes were identified that were involved in numerous biological pathways and functions including calcium signalling, sphingolipid metabolism and parasite defence. Conclusion The findings provide a comprehensive database of gene expression in an important human pathogen, including transcriptional changes in genes involved in evasion of the host immune response, nutrient acquisition, energy production, calcium signalling, sphingolipid metabolism, egg production and tegumental function during development. This resource should help facilitate the identification and prioritization of new anti-schistosome drug and vaccine targets for the control of schistosomiasis. PMID:19320991

  16. Developmental gene expression profiles of the human pathogen Schistosoma japonicum

    Directory of Open Access Journals (Sweden)

    McManus Donald P

    2009-03-01

    Full Text Available Abstract Background The schistosome blood flukes are complex trematodes and cause a chronic parasitic disease of significant public health importance worldwide, schistosomiasis. Their life cycle is characterised by distinct parasitic and free-living phases involving mammalian and snail hosts and freshwater. Microarray analysis was used to profile developmental gene expression in the Asian species, Schistosoma japonicum. Total RNAs were isolated from the three distinct environmental phases of the lifecycle – aquatic/snail (eggs, miracidia, sporocysts, cercariae, juvenile (lung schistosomula and paired but pre-egg laying adults and adult (paired, mature males and egg-producing females, both examined separately. Advanced analyses including ANOVA, principal component analysis, and hierarchal clustering provided a global synopsis of gene expression relationships among the different developmental stages of the schistosome parasite. Results Gene expression profiles were linked to the major environmental settings through which the developmental stages of the fluke have to adapt during the course of its life cycle. Gene ontologies of the differentially expressed genes revealed a wide range of functions and processes. In addition, stage-specific, differentially expressed genes were identified that were involved in numerous biological pathways and functions including calcium signalling, sphingolipid metabolism and parasite defence. Conclusion The findings provide a comprehensive database of gene expression in an important human pathogen, including transcriptional changes in genes involved in evasion of the host immune response, nutrient acquisition, energy production, calcium signalling, sphingolipid metabolism, egg production and tegumental function during development. This resource should help facilitate the identification and prioritization of new anti-schistosome drug and vaccine targets for the control of schistosomiasis.

  17. Human mobility networks and persistence of rapidly mutating pathogens

    CERN Document Server

    Aleta, Alberto; Meloni, Sandro; Poletto, Chiara; Colizza, Vittoria; Moreno, Yamir

    2016-01-01

    Rapidly mutating pathogens may be able to persist in the population and reach an endemic equilibrium by escaping hosts' acquired immunity. For such diseases, multiple biological, environmental and population-level mechanisms determine the dynamics of the outbreak, including pathogen's epidemiological traits (e.g. transmissibility, infectious period and duration of immunity), seasonality, interaction with other circulating strains and hosts' mixing and spatial fragmentation. Here, we study a susceptible-infected-recovered-susceptible model on a metapopulation where individuals are distributed in subpopulations connected via a network of mobility flows. Through extensive numerical simulations, we explore the phase space of pathogen's persistence and map the dynamical regimes of the pathogen following emergence. Our results show that spatial fragmentation and mobility play a key role in the persistence of the disease whose maximum is reached at intermediate mobility values. We describe the occurrence of differen...

  18. From Environment to Man: Genome Evolution and Adaptation of Human Opportunistic Bacterial Pathogens

    OpenAIRE

    Estelle Jumas-Bilak; Hélène Marchandin; Brigitte Lamy; Anne Lotthé; Fabien Aujoulat; Frédéric Roger; Alice Bourdier

    2012-01-01

    Environment is recognized as a huge reservoir for bacterial species and a source of human pathogens. Some environmental bacteria have an extraordinary range of activities that include promotion of plant growth or disease, breakdown of pollutants, production of original biomolecules, but also multidrug resistance and human pathogenicity. The versatility of bacterial life-style involves adaptation to various niches. Adaptation to both open environment and human specific niches is a major challe...

  19. Management and Analysis of Monitoring of Food-borne Diseases%食源性疾病监测管理与分析

    Institute of Scientific and Technical Information of China (English)

    宁巧玲

    2016-01-01

    The paper studies the monitoring management of food-borne diseases and analyzes the related issues taking the food-borne disease as a topic, firstly make a brief summary of the development situation of world food-borne diseases, intro-duces the concept and connation of food-borne diseases according to the specific condition of our country, analyzes its de-velopment trend and causes, and especially discusses the related measures of active monitoring management on the basis of the above, hoping to arouse more attention and wider communication, thus providing some valuable information of the theo-retical research work and monitoring management practice work for reference.%本文以食源性疾病作为研究主题,探讨食源性疾病监测管理与分析及相关问题。首先结合世界食源性疾病的发展情况对其进行了简要概述;主要以我国的具体情况为准,介绍了食源性疾病的概念与内涵,分析了它的发展趋势及原因,并以此作为基础,重点讨论了主动监测管理的相关措施。希望能够通过本文初步论述可以引起更多的关注与更为广泛的交流,从而为该方面的理论研究工作怀监测管理实践工作提供一些有价值的信息,以供参考。

  20. Description of Clean and Healthy Behavior of Food Borne Disease Among by School Children Age in Babat Jerawat I Elementary School, District Pakal Surabaya

    OpenAIRE

    Hidayat Heny Sholikhah; Florentina Sustini

    2014-01-01

    Background: Incidence of food borne disease, such as diarrhea, typhoid and hookworm infection in school childrenwere still sufficient susceptible. Lack of clean and healthy behavior became primary cause, so that the agent can easilyenter to the body through the food consumed. The purpose of this study was to descript the clean and healthy behaviors by school children age at Babat Jerawat I Elementary School, District Pakal Surabaya. Methods: This study was a crosssectional study. The sample o...

  1. 建立食源性疾病危机管理机制探讨%Discussion of establishment of crisis management mechanism of food-borne diseases

    Institute of Scientific and Technical Information of China (English)

    刘新荣; 孙爱国; 郭琴; 王艳

    2011-01-01

    Food-borne diseases severely jeopardize public health and life safety, disrupt normal production and life orders and endanger social stability. In order to solve the problems such as lagged crisis management mechanism of food-borne diseases, personnel structure, professional handling skills and laboratory testing that exists in the current centers for disease control, this paper proposes the crisis management mechanism of food-borne diseases to strengthen the leadership, establish and improve the crisis management operating mechanism of food-borne diseases, improve the professional team quality and strengthen the responsibilities of centers for disease control, and speed up the construction of laboratory capacity and improve the conditions of laboratory equipment.%食源性疾病严重危害公众健康和生命安全,扰乱正常的生产生活秩序,危及社会安定.本文针对当前疾病预防控制机构存在的食源性疾病管理机制滞后、人员结构、专业处置技能、实验室检测等方面存在的问题,提出了强化领导;建立完善食源性疾病危机管理运行机制;提高专业队伍素质,强化疾病控制机构的责任;加快实验室能力建设,完善实验室设备条件的食源性疾病危机管理机制.

  2. The arable plant ecosystem as battleground for emergence of human pathogens

    Directory of Open Access Journals (Sweden)

    Leo eVan Overbeek

    2014-03-01

    Full Text Available Disease incidences related to Escherichia coli and Salmonella enterica infections by consumption of (fresh vegetables, sprouts and occasionally fruits made clear that these pathogens are not only transmitted to humans via the ‘classical’ routes of meat, eggs and dairy products, but also can be transmitted to humans via plants or products derived from plants. Nowadays, it is of major concern that these human pathogens, especially the ones belonging to the taxonomical family of Enterobacteriaceae, become adapted to environmental habitats without losing their virulence to humans. Adaptation to the plant environment would lead to longer persistence in plants, increasing their chances on transmission to humans via consumption of plant-derived food. One of the mechanisms of adaptation to the plant environment in human pathogens, proposed in this paper, is horizontal transfer of genes from different microbial communities present in the arable ecosystem, like the ones originating from soil, animal digestive track systems (manure, water and plants themselves. Genes that would confer better adaptation to the phytosphere might be genes involved in plant colonization, stress resistance and nutrient acquisition and utilization. Because human pathogenic enterics often were prone to genetic exchanges via phages and conjugative plasmids, it was postulated that these genetic elements may be hold key responsible for horizontal gene transfers between human pathogens and indigenous microbes in agroproduction systems. In analogy to zoonosis, we coin the term phytonosis for a human pathogen that is transmitted via plants and not exclusively via animals.

  3. Escherichia coli O157:H7 - An Emerging Pathogen in foods of Animal Origin

    Directory of Open Access Journals (Sweden)

    Ch. Bindu Kiranmayi

    Full Text Available Escherichia coli O157:H7 is an emerging public health concern in most countries of the world. E. coli O157:H7 was known to be a human pathogen for nearly 24 years. EHEC O157 infection is estimated to be the fourth most costly food borne disease in Canada and USA, not counting the cost of possible litigation. E. coli O157:H7 and Salmonella are the leading causes of produce related outbreaks, accounting for 20 and 30% respectively. The authority of the Federal Meat Inspection Act, FSIS (Food Safety and Inspection Service declared Escherichia coli O157:H7, an adulterant in raw ground beef and enforced “zero tolerance” (USDA-FSIS, 17 December 1998. Because of the severity of these illnesses and the apparent low infective dose (less than 10 cells, Escherichia coli O157:H7 is considered one of the most serious of known food borne pathogens. Escherichia coli O157:H7 is mainly pathogenic to human but in cattle and other animals, it did not induce any clinical disease except diarrhea. So, these animals act as carriers to Escherichia coli O157:H7. The majority transmission is through eating of undercooked contaminated ground meat and consumption of raw milk, raw vegetables, fruits contaminated by water, cheese, curd and also through consumption of sprouts, lettuce and juice. The conventional isolation procedure includes growth in enrichment broth like modified EC (E. coli broth or modified tryptic soy broth (mTSB Since the infection primarily occurs via faeco-oral route, the preventive measures include food hygiene measures like proper cooking of meat, consumption of pasteurized milk, washing fruits and vegetables especially those to be eaten raw and drinking chlorine treated water and personnel hygiene measures like washing hands after toilet visits. [Veterinary World 2010; 3(8.000: 382-389

  4. Cold plasma inactivation of human pathogens on foods and regulatory status update

    Science.gov (United States)

    Contamination of foods with human pathogens such as Salmonella, Listeria monocytogenes, Escherichia coli O157:H7, norovirus, and other pathogens is an ongoing challenge for growers and processors. In recent years, cold plasma has emerged as a promising antimicrobial treatment for fresh and fresh-cut...

  5. Pathogen sensing, subsequent signalling, and signalosome in human platelets.

    Science.gov (United States)

    Garraud, Olivier; Berthet, Julien; Hamzeh-Cognasse, Hind; Cognasse, Fabrice

    2011-04-01

    Beyond haemostasis, platelets exert a potent role in innate immunity and particularly in its inflammatory arm. The extent of this action remains however debatable, despite clear - and old - evidence of a link between platelets and infection. Platelets can sense infectious pathogens by pathogen recognition receptors and they can even discriminate between various types of infectious signatures. In reply, they can shape their capacity to respond by activating a signalosome and by producing different profiles of pro-inflammatory cytokines and related products. The links between pathogen sensing, signalosome activation and protein production, and their finely tuned regulation are still under investigation since platelets lack a nucleus and thus, canonical molecular biology and genomics apparati.

  6. Potentially pathogenic Escherichia coli in healthy, pasture-raised sheep on farms and at the abattoir in Brazil.

    Science.gov (United States)

    Maluta, Renato Pariz; Fairbrother, John Morris; Stella, Ariel Eurides; Rigobelo, Everlon Cid; Martinez, Roberto; de Ávila, Fernando Antonio

    2014-02-21

    Sheep harbor pathogenic Escherichia coli, which may cause severe disease in humans. In this study, the prevalence of Shiga toxin-producing E. coli (STEC) and enteropathogenic E. coli (EPEC) was examined in sheep feces and carcasses on three farms and at an abattoir in Brazil. The isolates were further characterized for the presence of markers recently associated with disease in humans, to investigate their possible origin and role as food-borne pathogens. At the abattoir, 99 carcass samples yielded two STEC and 10 EPEC isolates while 101 fecal samples yielded five EPEC and eight STEC isolates. On the other hand, on the farms, 202 samples yielded 44 STEC and eight EPEC isolates. The 77 isolates were typed by PFGE. Isolates with the same PFGE pattern and also those that were not restricted with XbaI were termed as "clones" (n=49). The isolates of any one clone mostly originated from the same sampling site. In addition, seven isolates encoded for novel Stx2 variants and five for Stx2e, the subtype related to porcine edema disease, which was for the first time isolated from sheep feces and carcasses. Also, three stx2-only isolates harbored genes of predicted Stx2 variants that were formed by A and B subunits of different types including Stx2a and Stx2d. The EPEC isolates were heterogeneous, 21 (91.3%) of them possessing efa1, ehxA, lpfAO113 or paa genes associated with diarrhea in humans. Thus, using markers recently associated with disease, we have demonstrated that E. coli similar to those pathogenic for humans are present in the sheep intestinal microflora, particularly at the abattoir, underlining the potential for food-borne transmission.

  7. Experimental Reservoirs of Human Pathogens: The Vibrio Cholerae Paradigm (7th Annual SFAF Meeting, 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Colwell, Rita [University of Maryland

    2012-06-01

    Rita Colwell on "Experimental Reservoirs of Human Pathogens: The Vibrio cholerae paradigm" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  8. Abundance of sewage-pollution indicator and human pathogenic bacteria in a tropical estuarine complex

    Digital Repository Service at National Institute of Oceanography (India)

    Nagvenkar, G.S.; Ramaiah, N.

    Studies on abundance and types of various pollution indicator bacterial populations from tropical estuaries are rare. This study was aimed to estimate current levels of pollution indicator as well as many groups of human pathogenic bacteria...

  9. [Advances in humans and animals opportunistic pathogens from environment infecting plants by crossing kingdoms].

    Science.gov (United States)

    Huang, Min; Wu, Yixin; He, Pengfei

    2016-02-04

    Some pathogenic microorganisms ubiquitous in the environment could cross kingdoms to infect diverse hosts. Several cross-kingdom human pathogens were summarized in this paper, including Serratia marcescens, Enterobacter cloacae and Pseudomonas aeuriginosa. They are ubiquitous in the nature and could cause plant diseases using the same or different infection strategies with which they infect humans and broaden host range. Among these bacteria, Klebsiella pneumoniae causes top rot disease of maize in the nature, revealing some plants in the environment could serve as a reservoir of various pathogens which might infect animals and probably humans when conditions are favorable, and even potentially harm food. Research on these cross-kingdom pathogens may play a very important role in the epidemiology of human, animal and plant diseases and be a hot topic in environment science.

  10. Genome sequence of the human pathogen Vibrio cholerae Amazonia.

    NARCIS (Netherlands)

    Thompson, C.C.; Marin, M.A.; Dias, G.M.; Dutilh, B.E.; Edwards, R.A.; Iida, T.; Thompson, F.L.; Vicente, A.C.

    2011-01-01

    Vibrio cholerae O1 Amazonia is a pathogen that was isolated from cholera-like diarrhea cases in at least two countries, Brazil and Ghana. Based on multilocus sequence analysis, this lineage belongs to a distinct profile compared to strains from El Tor and classical biotypes. The genomic analysis rev

  11. Human enteric pathogen internalization by root uptake into food crops

    Science.gov (United States)

    With an increasing number of outbreaks and illnesses associated with pre-harvest contaminated produce, understanding the potential and mechanisms of produce contamination by enteric pathogens can aid in the development of preventative measures and post-harvest processing to reduce microbial populati...

  12. Genome sequence of the human pathogen Vibrio cholerae Amazonia.

    NARCIS (Netherlands)

    Thompson, C.C.; Marin, M.A.; Dias, G.M.; Dutilh, B.E.; Edwards, R.A.; Iida, T.; Thompson, F.L.; Vicente, A.C.

    2011-01-01

    Vibrio cholerae O1 Amazonia is a pathogen that was isolated from cholera-like diarrhea cases in at least two countries, Brazil and Ghana. Based on multilocus sequence analysis, this lineage belongs to a distinct profile compared to strains from El Tor and classical biotypes. The genomic analysis

  13. Bottlenecks in the Transferability of Antibiotic Resistance from Natural Ecosystems to Human Bacterial Pathogens

    OpenAIRE

    Martínez, José L.

    2012-01-01

    It is generally accepted that resistance genes acquired by human pathogens through horizontal gene transfer originated in environmental, non-pathogenic bacteria. As a consequence, there is increasing concern on the roles that natural, non-clinical ecosystems, may play in the evolution of resistance. Recent studies have shown that the variability of determinants that can provide antibiotic resistance on their expression in a heterologous host is much larger than what is actually found in human...

  14. Characterization of the interaction between the human pathogen Listeria monocytogenes and the model host C. elegans

    DEFF Research Database (Denmark)

    Simonsen, Karina Trankjær; Nielsen, Jesper Sejrup; Thomsen, Line E.;

    . elegans. Finally, we have developed a liquid based killing assay which enables us to set up a high-throughput screening system for the identification of L. monocytogenes virulence genes required for host-pathogen interactions.     References:   [1]: Kurz, C. L., and Ewbank, J. J. (2007) Curr Opin....... In addition, C. elegans is a promising model for the identification of novel virulence factors in various pathogens. A large number of human, animal, plant and insect pathogens have been shown to kill the worm, when C. elegans was allowed to feed on pathogens in stead of its normal laboratory diet [1......, which has been shown to kill C. elegans through the production of a toxic secondary metabolite [3] and Staphylococcus aureus, which establishes a persistent infection in the gut of the worm, leading to its death [4].   Recently, the facultative intracellular human pathogen Listeria monocytogenes has...

  15. Human soil-borne pathogens and risks associated with land use change

    Science.gov (United States)

    Pereg, Lily

    2017-04-01

    Soil is a source of pathogenic, neutral and beneficial microorganisms. Natural events and anthropogenic activity can affect soil biodiversity and influence the balance and distribution of soil-borne human pathogens. Important bacterial and fungal pathogens, such as Bacillus anthracis, Coxiella bernetii, Clostridium tetani, Escherichia coli 0157:H7, Listeria monocytogenes, Aspergillus fumigatus and Sporothrix schenckii will be discussed. This presentation will concentrate on soil pathogenic microorganisms and the effects of land use change on their prevalence and distribution. In particular, the potential of agricultural soil cultivation to enhance pathogen transmission to human through the release of soil microbes into the air attached to dust particles, contamination of waterways and infection of food plants and animal. Emerging solutions, such as biocontrol and probiotics, will be discussed.

  16. Antibacterial Activity of Eighteen Edible Spice Extracts on Five Food-borne Bacteria%十八种辛香料对五种食源性致病菌的抑菌研究

    Institute of Scientific and Technical Information of China (English)

    卢惠妮; 潘迎捷; 赵勇; 孙晓红

    2010-01-01

    本实验研究18种辛香料对五种食源性病原菌:单增李斯特菌,大肠杆菌 O157:H7,肠炎沙门氏菌,副溶血性弧菌和金黄色葡萄球菌的抑制作用.辛香料以60℃蒸馏水浸提.研究各种辛香料的最低抑菌浓度(80~5 mg/mL)以及经100℃处理15 min和121 ℃处理15 min的稳定性.结果表明,大部分辛香料具有良好的抑菌效果,尤其是丁香和桂皮对副溶血弧菌和金黄色葡萄球菌的最低抑菌浓度为5 mg/mL.经热处理部分香料失去了抑制作用,如八角,茴香,五香粉,海南白和黑胡椒,但大多数香料保持抑菌效果.这些结果表明,香料可抑制感染海产品的病原菌,同时在加工香料的过程中应该避免高温处理.%The antimicrobial effects of eighteen spices were screened against five food-borne bacterial strains: Listeria monocytogenes,Escherichia coli O157 : H7,Salmonella enteritidis,Vibrio parahaemolyticus,and Staphylococcus aureus.Spices were extracted by hot water(60 ℃).The minimum inhibitory concentrations(MICs)of extracts were determined by the agar dilution method ranged from 80 to 5 mg/mL;The stability of extracts were measured by heat treatment(100℃-15 min;121 ℃-15 min).The results showed that most spices have nice antibacterial activity,especially clove and cinnamon powder;The lowest MIC was 5 mg/mL observed in clove and Cassia twig powder act on V.parahaemolyticus and Staphylococcus aureus.By heat treatment,part of the spices apparently lost its inhibitory effect,such as star anise,fermel,spiced powder,Hainan white and black pepper,but the majority of spices keep their antibacterial effect.These results suggest that the spices can be practical for protecting seafood from the risk of contamination by food-borne pathogens and avoid high temperature treatment during processing the spices.

  17. Results of monitoring of food-borne diseases in Nanshan District of Shenzhen in 2012%深圳市南山区2012年食源性疾病监测结果分析

    Institute of Scientific and Technical Information of China (English)

    胡永松; 李维克

    2013-01-01

    Objective understand the incidence of food-borne diseases in Nanshan district of Shenzhen city and to provide evidence for formulating prevention and control measures.Methods The data of food-borne diseases from march 2012 to February 2013 in Nanshan disrtrict of Zhenzhen were collected and the prevalent features were analyzed with descriptive epidemiologic mwthod.Results A totally of 4 237 cases including 2232 males and 2005 femaless.with a male to female ratio of 1.0541.without significant differences(P>0.05).The infection rate in 15~64years age group accounted for 79.92% amd 2 584 cases were infected with bacterial pathogens accountedfor 61.37%.The clinical symptoms from higher to the lowest were in the order of dirrhoea>stamochahe>vomiting>fever.Concltusions Food-borne diseases were prevalent in summer and suturn and the children in the age group of 15~64 years with diarrhea and stamochache were target population for monitoring.%目的 了解广东省深圳市南山区食源性疾病流行现状,掌握其发病的规律,为制定预防控制对策提供科学依据. 方法 收集2012年3月~2013年2月南山区食源性疾病监测资料,采用描述性流行病学方法,将获得的资料用SPSS 17.0进行处理,分析南山区食源性疾病流行特征. 结果 2012年3月~2013年2月共检测患食源性疾病4 237例,其中男性2 232例,女性2 005例,男女之比为1.0541,差异无统计学意义(P>0.05).15~64岁人群是食源性疾病高发人群,占79.92%.细菌性食源性疾病患者为2 584例,占61.37%,各种症状的发生率为:腹泻(68.73%)>腹痛(68.26%)>呕吐(26.50%)>发热(20.27%). 结论 夏季为食源性疾病高发季节,15~64岁人群和腹泻,腹痛和呕吐患者是监测的主要目标人群.

  18. Adhesins of human pathogens from the genus Yersinia.

    Science.gov (United States)

    Leo, Jack C; Skurnik, Mikael

    2011-01-01

    Bacteria of the Gram-negative genus Yersinia are environmentally ubiquitous. Three species are of medical importance: the intestinal pathogens Y. enterocolitica and Y. pseudotuberculosis, and the plague bacillus Y. pestis. The two former species, spread by contaminated food or water, cause a range of gastrointestinal symptoms and, rarely, sepsis. On occasion, the primary infection is followed by autoimmune sequelae such as reactive arthritis. Plague is a systemic disease with high mortality. It is a zoonosis spread by fleas, or more rarely by droplets from individuals suffering from pneumonic plague. Y. pestis is one of the most virulent of bacteria, and recent findings of antibiotic-resistant strains together with its potential use as a bioweapon have increased interest in the species. In addition to being significant pathogens in their own right, the yersiniae have been used as model systems for a number of aspects of pathogenicity. This chapter reviews the molecular mechanisms of adhesion in yersiniae. The enteropathogenic species share three adhesins: invasin, YadA and Ail. Invasin is the first adhesin required for enteric infection; it binds to β(1) integrins on microfold cells in the distal ileum, leading to the ingestion of the bacteria and allows them to cross the intestinal epithelium. YadA is the major adhesin in host tissues. It is a multifunctional protein, conferring adherence to cells and extracellular matrix components, serum and phagocytosis resistance, and the ability to autoagglutinate. Ail has a minor role in adhesion and serum resistance. Y. pestis lacks both invasin and YadA, but expresses several other adhesins. These include the pH 6 antigen and autotransporter adhesins. Also the plasminogen activator of Y. pestis can mediate adherence to host cells. Although the adhesins of the pathogenic yersiniae have been studied extensively, their exact roles in the biology of infection remain elusive.

  19. Phenotypic and genotypic characterization of Salmonella Typhimurium variant 5- isolates associated with an outbreak of food-borne disease in Paz de Rio, Boyacá, Colombia, in 2010 = Caracterización fenotípica y genotípica de Salmonella Typhimurium variante 5- asociada a un brote de enfermedad transmitida por alimentos en el municipio de Paz de Río, Boyacá, 2010 = Caracterización fenotípica y genotípica de Salmonella Typhimurium variante 5- asociada a un brote de enfermedad transmitida por alimentos en el municipio de Paz de Río, Boyacá, 2010

    Directory of Open Access Journals (Sweden)

    Díaz Osorio, Miguel Ángel

    2014-01-01

    Full Text Available Introduction: Salmonella enterica serotype Typhimuri-um variant 5- is a pathogen closely related to animals, especially pigeons, which has been also associ- ated in rare cases with sporadic infections in humans. However, epidemiological surveillance systems have enabled the detection of this variant in human out- breaks. Objective: To characterize by means of phenotypic and genotypic techniques the isolates of Salmonella Typhimurium variant 5- associated with an outbreak of food-borne disease in Paz de Rio, Boyacá, Colombia (2010, in order to establish their molecular relationships. Materials and methods: Twelve isolates of Salmonella -spp., were analyzed by biochemical, serotyping and antimicrobial susceptibility tests. Pulsed-field gel electrophoresis (PFGE with Xball Blnl enzymes was used to establish their molecular relationships Results: All isolates were confirmed as Salmonella spp. They were resistant to tetracycline and streptomycin and sensitive to the rest of antibiotics tested. Eleven isolates were identified as Salmonella Typhimurium variant 5- and grouped in COIN10.JPX.X01.0168 pattern using the enzyme Xball two isolates in this group were confirmed using the enzyme Blnl with the COIN10.JPX.A26.0002 pattern. One isolate was identified as Salmonella Typhimurium with COIN10.JPX.X01.0221 pattern with the enzyme Xbal Conclusion: This is the first outbreak in Colombia of foodborne illness epidemiologically associated with isolates of Typhimurium variant 5 -, which Epidemiologic Sur were phenotypically and genetically related.

  20. Occurrence of human pathogenic Clostridium botulinum among healthy dairy animals: an emerging public health hazard.

    Science.gov (United States)

    Abdel-Moein, Khaled A; Hamza, Dalia A

    2016-01-01

    The current study was conducted to investigate the occurrence of human pathogenic Clostridium botulinum in the feces of dairy animals. Fecal samples were collected from 203 apparently healthy dairy animals (50 cattle, 50 buffaloes, 52 sheep, 51 goats). Samples were cultured to recover C. botulinum while human pathogenic C. botulinum strains were identified after screening of all C. botulinum isolates for the presence of genes that encode toxins type A, B, E, F. The overall prevalence of C. botulinum was 18.7% whereas human pathogenic C. botulinum strains (only type A) were isolated from six animals at the rates of 2, 2, 5.8, and 2% for cattle, buffaloes, sheep, and goats, respectively. High fecal carriage rates of C. botulinum among apparently healthy dairy animals especially type A alarm both veterinary and public health communities for a potential role which may be played by dairy animals in the epidemiology of such pathogen.

  1. Pathogen inactivation of human serum facilitates its clinical use for islet cell culture and subsequent transplantation.

    Science.gov (United States)

    Ståhle, Magnus U; Brandhorst, Daniel; Korsgren, Olle; Knutson, Folke

    2011-01-01

    Serum is regarded as an essential supplement to promote survival and growth of cells during culture. However, the potential risk of transmitting diseases disqualifies the use of serum for clinical cell therapy in most countries. Hence, most clinical cell therapy programs have replaced human serum with human serum albumin, which can result in inferior quality of released cell products. Photochemical treatment of different blood products utilizing Intercept® technology has been shown to inactivate a broad variety of pathogens of RNA and DNA origin. The present study assesses the feasibility of using pathogen-inactivated, blood group-compatible serum for use in human pancreatic islet culture. Isolated human islets were cultured at 37°C for 3-4 days in CMRL 1066 supplemented with 10% of either pathogen-inactivated or nontreated human serum. Islet quality assessment included glucose-stimulated insulin release (perifusion), ADP/ATP ratio, cytokine expression, and posttransplant function in diabetic nude mice. No differences were found between islets cultured in pathogen-inactivated or control serum regarding stimulated insulin release, intracellular insulin content, and ADP/ATP ratio. Whether media was supplemented with treated or nontreated serum, islet expression of IL-6, IL-8, MCP-1, or tissue factor was not affected. The final diabetes-reversal rate of mice receiving islets cultured in pathogen-inactivated or nontreated serum was 78% and 87%, respectively (NS). As reported here, pathogen-inactivated human serum does not affect viability or functional integrity of cultured human islets. The implementation of this technology for RNA- and DNA-based pathogen inactivation should enable reintroduction of human serum for clinical cell therapy.

  2. STUDIES ON SYNBIOTIC BARLEY GRAIN EXTRACT AGAINST SOME HUMAN PATHOGENS

    Directory of Open Access Journals (Sweden)

    T. Sheela

    2012-01-01

    Full Text Available This study evaluated that effect of prebiotic food containing oligosaccharide to enhance the growth and activity of probiotic strains. Barley grains probioticated using different strains of probiotics are Lactobacillus kefiranofaciens, Candida kefir,and saccharomyces boluradii. To select a suitable prebiotics like inulin for the development of Synbiotic barley and tested for antibacterial activity against diarrhoea causing pathogen such as Esherichia coli, Staphylococcus aureus, Salmonella paratyphi A, Shigella dysenteriae, Vibrio cholerae. Analysis of identified compound from synbiotic barley grain using GC-MS.

  3. From Environment to Man: Genome Evolution and Adaptation of Human Opportunistic Bacterial Pathogens

    Science.gov (United States)

    Aujoulat, Fabien; Roger, Frédéric; Bourdier, Alice; Lotthé, Anne; Lamy, Brigitte; Marchandin, Hélène; Jumas-Bilak, Estelle

    2012-01-01

    Environment is recognized as a huge reservoir for bacterial species and a source of human pathogens. Some environmental bacteria have an extraordinary range of activities that include promotion of plant growth or disease, breakdown of pollutants, production of original biomolecules, but also multidrug resistance and human pathogenicity. The versatility of bacterial life-style involves adaptation to various niches. Adaptation to both open environment and human specific niches is a major challenge that involves intermediate organisms allowing pre-adaptation to humans. The aim of this review is to analyze genomic features of environmental bacteria in order to explain their adaptation to human beings. The genera Pseudomonas, Aeromonas and Ochrobactrum provide valuable examples of opportunistic behavior associated to particular genomic structure and evolution. Particularly, we performed original genomic comparisons among aeromonads and between the strictly intracellular pathogens Brucella spp. and the mild opportunistic pathogens Ochrobactrum spp. We conclude that the adaptation to human could coincide with a speciation in action revealed by modifications in both genomic and population structures. This adaptation-driven speciation could be a major mechanism for the emergence of true pathogens besides the acquisition of specialized virulence factors. PMID:24704914

  4. Description of Clean and Healthy Behavior of Food Borne Disease Among by School Children Age in Babat Jerawat I Elementary School, District Pakal Surabaya

    Directory of Open Access Journals (Sweden)

    Hidayat Heny Sholikhah

    2014-08-01

    Full Text Available Background: Incidence of food borne disease, such as diarrhea, typhoid and hookworm infection in school childrenwere still sufficient susceptible. Lack of clean and healthy behavior became primary cause, so that the agent can easilyenter to the body through the food consumed. The purpose of this study was to descript the clean and healthy behaviors by school children age at Babat Jerawat I Elementary School, District Pakal Surabaya. Methods: This study was a crosssectional study. The sample of this study were 112 of fifth grade students at Babat Jerawat I Elementary school, District Pakal Surabaya, selected by purposive sampling of 121 students who met the inclusion criteria. Data of clean and healthy behavior were collected by observation and interviews focused on a group of school children using questionnaires, checklists and interview guides. Data analysis was done by using descriptive analysis. Results: The results showed that the clean and healthy behaviors about food borne disease, the majority of school children in Elementary school Babat Jerawat I District Pakal Surabaya included in good criteria (51.8% and small portion of these included less category (48.2%. Conclusion:Clean and Healthy Behavior of food borne disease in school children age had good criteria, but still need attention formany factors that influence it, such as the availability of facilities, affordability snacks outside of school and examples ofunhealthy behaviors in family environment. Recommendation: Improve the cooperation between the school and localhealth officials to tighten rules on the management of snack vending around schools, and do continuous education both within the school and the child’s school community.

  5. Case Report: An Outbreak of Food-Borne Typhoid Fever Due to Salmonella enterica Serotype Typhi in Japan Reported for the First Time in 16 Years.

    Science.gov (United States)

    Kobayashi, Tetsuro; Kutsuna, Satoshi; Hayakawa, Kayoko; Kato, Yasuyuki; Ohmagari, Norio; Uryu, Hideko; Yamada, Ritsuko; Kashiwa, Naoyuki; Nei, Takahito; Ehara, Akihito; Takei, Reiko; Mori, Nobuaki; Yamada, Yasuhiro; Hayasaka, Tomomi; Kagawa, Narito; Sugawara, Momoko; Suzaki, Ai; Takahashi, Yuno; Nishiyama, Hiroyuki; Morita, Masatomo; Izumiya, Hidemasa; Ohnishi, Makoto

    2016-02-01

    For the first time in 16 years, a food-borne outbreak of typhoid fever due to Salmonella enterica serotype Typhi was reported in Japan. Seven patients consumed food in an Indian buffet at a restaurant in the center of Tokyo, while one was a Nepali chef in the restaurant, an asymptomatic carrier and the implicated source of this outbreak. The multiple-locus variable-number tandem repeat analysis showed 100% consistency in the genomic sequence for five of the eight cases. © The American Society of Tropical Medicine and Hygiene.

  6. Disinfection and removal of human pathogenic bacteria in arctic waste stabilization ponds

    DEFF Research Database (Denmark)

    Huang, Yannan; Hansen, Lisbeth Truelstrup; Ragush, Colin M.

    2017-01-01

    Wastewater stabilization ponds (WSPs) are commonly used to treat municipal wastewater in Arctic Canada. The biological treatment in the WSPs is strongly influenced by climatic conditions. Currently, there is limited information about the removal of fecal and pathogenic bacteria during the short...... cool summer treatment season. With relevance to public health, the objectives of this paper were to determine if treatment in arctic WSPs resulted in the disinfection (i.e., removal of fecal indicator bacteria, Escherichia coli) and removal of selected human bacterial pathogens from the treated...... treatment of the wastewater with a 2–3 Log removal of generic indicator E. coli. The bacterial pathogens Salmonella spp., pathogenic E. coli, and Listeria monocytogenes, but not Campylobacter spp. and Helicobacter pylori, were detected in the untreated and treated wastewater, indicating that human...

  7. Plants as a habitat for beneficial and/or human pathogenic bacteria.

    Science.gov (United States)

    Tyler, Heather L; Triplett, Eric W

    2008-01-01

    Non-plant pathogenic endophytic bacteria can promote plant growth, improve nitrogen nutrition, and, in some cases, are human pathogens. Recent work in several laboratories has shown that enteric bacteria are common inhabitants of the interior of plants. These observations led to the experiments that showed the entry into plants of enteric human pathogens such as Salmonella and E. coli O157:H7. The extent of endophytic colonization by strains is regulated by plant defenses and several genetic determinants necessary for this interior colonization in endophytic bacteria have been identified. The genomes of four endophytic bacteria now available should promote discovery of other genes that contribute to this phenotype. Common virulence factors in plant and animal pathogens have also been described in bacteria that can infect both plant and animal models. Future directions in all of these areas are proposed.

  8. Bottlenecks in the transmission of antibiotic resistance from natural ecosystems to human bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Jose L Martinez

    2012-01-01

    Full Text Available It is generally accepted that resistance genes acquired by human pathogens trough horizontal gene transfer have been originated in environmental, non pathogenic bacteria. As the consequence, there exists an increasing concern on the role that natural, non-clinical ecosystems, may play on the evolution of resistance. Recent studies have shown that the variability of determinants that can provide antibiotic resistance upon their expression in a heterologous host is much larger than what is actually found in human pathogens. Along the review, the role that different processes as founder effect, ecological connectivity, fitness costs or second-order selection may have on the establishment of a specific resistance determinant in the population of bacterial pathogens is analysed.

  9. Immune Recognition of Latency-insitigating Pathogens by Human Dendritic Cells

    DEFF Research Database (Denmark)

    Søndergaard, Jonas Nørskov

    Latent infections with the human pathogenic microorganisms Mycobacterium tuberculosis (Mtb) and the human immunodeficiency virus (HIV) are creating some of the most devastating pandemics to date, with great impact on the infected people’s lives, their expected lifetime, as well as general costs...

  10. Disease induction by human microbial pathogens in plant-model systems: potential, problems and prospects

    NARCIS (Netherlands)

    Baarlen, van P.; Belkum, van A.; Thomma, B.P.H.J.

    2007-01-01

    Relatively simple eukaryotic model organisms such as the genetic model weed plant Arabidopsis thaliana possess an innate immune system that shares important similarities with its mammalian counterpart. In fact, some human pathogens infect Arabidopsis and cause overt disease with human symptomology.

  11. Interaction of Campylobacter spp. and human probiotics in chicken intestinal mucus.

    Science.gov (United States)

    Ganan, M; Martinez-Rodriguez, A J; Carrascosa, A V; Vesterlund, S; Salminen, S; Satokari, R

    2013-03-01

    Campylobacter is the most common cause of bacterial food-borne diarrhoeal disease throughout the world. The principal risk of human contamination is handling and consumption of contaminated poultry meat. To colonize poultry, Campylobacter adheres to and persists in the mucus layer that covers the intestinal epithelium. Inhibiting adhesion to the mucus could prevent colonization of the intestine. The aim of this study was to investigate in vitro the protective effect of defined commercial human probiotic strains on the adhesion of Campylobacter spp. to chicken intestinal mucus, in a search for alternatives to antibiotics to control this food-borne pathogen. The probiotic strains Lactobacillus rhamnosus GG and Propionibacterium freudenreichii ssp. shermanii JS and a starter culture strain Lactococcus lactis ssp. lactis adhered well to chicken intestinal mucus and were able to reduce the binding of Campylobacter spp. when the mucus was colonized with the probiotic strain before contacting the pathogen. Human-intended probiotics could be useful as prophylactics in poultry feeding for controlling Campylobacter spp. colonization. © 2012 Blackwell Verlag GmbH.

  12. Prevalence of plant beneficial and human pathogenic bacteria isolated from salad vegetables in India.

    Science.gov (United States)

    Nithya, Angamuthu; Babu, Subramanian

    2017-03-14

    The study aimed at enumerating, identifying and categorizing the endophytic cultivable bacterial community in selected salad vegetables (carrot, cucumber, tomato and onion). Vegetable samples were collected from markets of two vegetable hot spot growing areas, during two different crop harvest seasons. Crude and diluted vegetable extracts were plated and the population of endophytic bacteria was assessed based on morphologically distinguishable colonies. The bacterial isolates were identified by growth in selective media, biochemical tests and 16S rRNA gene sequencing. The endophytic population was found to be comparably higher in cucumber and tomato in both of the sampling locations, whereas lower in carrot and onion. Bacterial isolates belonged to 5 classes covering 46 distinct species belonging to 19 genera. Human opportunistic pathogens were predominant in carrot and onion, whereas plant beneficial bacteria dominated in cucumber and tomato. Out of the 104 isolates, 16.25% are human pathogens and 26.5% are human opportunistic pathogens. Existence of a high population of plant beneficial bacteria was found to have suppressed the population of plant and human pathogens. There is a greater potential to study the native endophytic plant beneficial bacteria for developing them as biocontrol agents against human pathogens that are harboured by plants.

  13. Generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies.

    Science.gov (United States)

    Ijaz, M Khalid; Zargar, Bahram; Wright, Kathryn E; Rubino, Joseph R; Sattar, Syed A

    2016-09-02

    Indoor air can be an important vehicle for a variety of human pathogens. This review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. The following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (Aspergillus, Penicillium, and Cladosporium spp and Stachybotrys chartarum), enteric viruses (noro- and rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (Clostridium difficile and Bacillus anthracis). An overview of methods for experimentally generating and recovering airborne human pathogens is included, along with a discussion of factors that influence microbial survival in indoor air. Available guidelines from the U.S. Environmental Protection Agency and other global regulatory bodies for the study of airborne pathogens are critically reviewed with particular reference to microbial surrogates that are recommended. Recent developments in experimental facilities to contaminate indoor air with microbial aerosols are presented, along with emerging technologies to decontaminate indoor air under field-relevant conditions. Furthermore, the role that air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings is discussed.

  14. Pathogen prevalence predicts human cross-cultural variability in individualism/collectivism.

    Science.gov (United States)

    Fincher, Corey L; Thornhill, Randy; Murray, Damian R; Schaller, Mark

    2008-06-07

    Pathogenic diseases impose selection pressures on the social behaviour of host populations. In humans (Homo sapiens), many psychological phenomena appear to serve an antipathogen defence function. One broad implication is the existence of cross-cultural differences in human cognition and behaviour contingent upon the relative presence of pathogens in the local ecology. We focus specifically on one fundamental cultural variable: differences in individualistic versus collectivist values. We suggest that specific behavioural manifestations of collectivism (e.g. ethnocentrism, conformity) can inhibit the transmission of pathogens; and so we hypothesize that collectivism (compared with individualism) will more often characterize cultures in regions that have historically had higher prevalence of pathogens. Drawing on epidemiological data and the findings of worldwide cross-national surveys of individualism/collectivism, our results support this hypothesis: the regional prevalence of pathogens has a strong positive correlation with cultural indicators of collectivism and a strong negative correlation with individualism. The correlations remain significant even when controlling for potential confounding variables. These results help to explain the origin of a paradigmatic cross-cultural difference, and reveal previously undocumented consequences of pathogenic diseases on the variable nature of human societies.

  15. Multiparameter viability assay for stress profiling applied to the food pathogen Listeria monocytogenes F2365

    NARCIS (Netherlands)

    Nocker, A.; Caspers, M.; Esveld-Amanatidou, A.; Vossen, J. van der; Schuren, F.; Montijn, R.; Kort, R.

    2011-01-01

    A novel generic approach for stress profiling was applied to Listeria monocytogenes strain F2365. This food-borne pathogen was exposed to gradients of five different stresses of increasing intensity, typically ranging from moderate to lethal conditions. The stress factors included heat, acidic pH, a

  16. High throughput screening strategies and technology platforms for detection of pathogens: An Introduction

    Science.gov (United States)

    Globally, foodborne pathogens are a major public health concern. In this chapter, we provide a broad description of the problem of food-borne diseases and current and future detection technologies for food safety assurance and prevention of foodborne illnesses. Current detection approaches include s...

  17. Targeted Disruption of Melanin Biosynthesis Genes in the Human Pathogenic Fungus Lomentospora prolificans and Its Consequences for Pathogen Survival

    Directory of Open Access Journals (Sweden)

    Ayat Al-Laaeiby

    2016-03-01

    Full Text Available The dematiaceous (melanised fungus Lomentospora (Scedosporium prolificans is a life-threatening opportunistic pathogen of immunocompromised humans, resistant to anti-fungal drugs. Melanin has been shown to protect human pathogenic fungi against antifungal drugs, oxidative killing and environmental stresses. To determine the protective role of melanin in L. prolificans to oxidative killing (H2O2, UV radiation and the polyene anti-fungal drug amphotericin B, targeted gene disruption was used to generate mutants of the pathogen lacking the dihydroxynaphthalene (DHN-melanin biosynthetic enzymes polyketide synthase (PKS1, tetrahydroxynapthalene reductase (4HNR and scytalone dehydratase (SCD1. Infectious propagules (spores of the wild-type strain 3.1 were black/brown, whereas spores of the PKS-deficient mutant ΔLppks1::hph were white. Complementation of the albino mutant ΔLppks1::hph restored the black-brown spore pigmentation, while the 4HNR-deficient mutant ΔLp4hnr::hph and SCD-deficient mutant ΔLpscd1::hph both produced orange-yellow spores. The mutants ΔLppks1::hph and ΔLp4hnr::hph showed significant reductions in spore survival following H2O2 treatment, while spores of ΔLpscd1::hph and the ΔLppks1::hph complemented strain ΔLppks1::hph:PKS showed spore survivals similar to strain 3.1. Spores of the mutants ΔLp4hnr::hph and ΔLpscd1::hph and complemented strain ΔLppks1::hph:PKS showed spore survivals similar to 3.1 following exposure to UV radiation, but survival of ΔLppks1::hph spores was significantly reduced compared to the wild-type strain. Strain 3.1 and mutants ΔLp4hnr::hph and ΔLppks1::hph:PKS were resistant to amphotericin B while, paradoxically, the PKS1- and SCD1-deficient mutants showed significant increases in growth in the presence of the antifungal drug. Taken together, these results show that while melanin plays a protective role in the survival of the pathogen to oxidative killing and UV radiation, melanin does not

  18. Targeted Disruption of Melanin Biosynthesis Genes in the Human Pathogenic Fungus Lomentospora prolificans and Its Consequences for Pathogen Survival.

    Science.gov (United States)

    Al-Laaeiby, Ayat; Kershaw, Michael J; Penn, Tina J; Thornton, Christopher R

    2016-03-24

    The dematiaceous (melanised) fungus Lomentospora (Scedosporium) prolificans is a life-threatening opportunistic pathogen of immunocompromised humans, resistant to anti-fungal drugs. Melanin has been shown to protect human pathogenic fungi against antifungal drugs, oxidative killing and environmental stresses. To determine the protective role of melanin in L. prolificans to oxidative killing (H₂O₂), UV radiation and the polyene anti-fungal drug amphotericin B, targeted gene disruption was used to generate mutants of the pathogen lacking the dihydroxynaphthalene (DHN)-melanin biosynthetic enzymes polyketide synthase (PKS1), tetrahydroxynapthalene reductase (4HNR) and scytalone dehydratase (SCD1). Infectious propagules (spores) of the wild-type strain 3.1 were black/brown, whereas spores of the PKS-deficient mutant ΔLppks1::hph were white. Complementation of the albino mutant ΔLppks1::hph restored the black-brown spore pigmentation, while the 4HNR-deficient mutant ΔLp4hnr::hph and SCD-deficient mutant ΔLpscd1::hph both produced orange-yellow spores. The mutants ΔLppks1::hph and ΔLp4hnr::hph showed significant reductions in spore survival following H₂O₂ treatment, while spores of ΔLpscd1::hph and the ΔLppks1::hph complemented strain ΔLppks1::hph:PKS showed spore survivals similar to strain 3.1. Spores of the mutants ΔLp4hnr::hph and ΔLpscd1::hph and complemented strain ΔLppks1::hph:PKS showed spore survivals similar to 3.1 following exposure to UV radiation, but survival of ΔLppks1::hph spores was significantly reduced compared to the wild-type strain. Strain 3.1 and mutants ΔLp4hnr::hph and ΔLppks1::hph:PKS were resistant to amphotericin B while, paradoxically, the PKS1- and SCD1-deficient mutants showed significant increases in growth in the presence of the antifungal drug. Taken together, these results show that while melanin plays a protective role in the survival of the pathogen to oxidative killing and UV radiation, melanin does not

  19. Antimicrobial activity of Uncaria tomentosa against oral human pathogens

    OpenAIRE

    Renzo Alberto Ccahuana-Vasquez; Silvana Soléo Ferreira dos Santos; Cristiane Yumi Koga-Ito; Antonio Olavo Cardoso Jorge

    2007-01-01

    Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria t...

  20. Human pathogen shown to cause disease in the threatened eklhorn coral Acropora palmata.

    Directory of Open Access Journals (Sweden)

    Kathryn Patterson Sutherland

    Full Text Available Coral reefs are in severe decline. Infections by the human pathogen Serratia marcescens have contributed to precipitous losses in the common Caribbean elkhorn coral, Acropora palmata, culminating in its listing under the United States Endangered Species Act. During a 2003 outbreak of this coral disease, called acroporid serratiosis (APS, a unique strain of the pathogen, Serratia marcescens strain PDR60, was identified from diseased A. palmata, human wastewater, the non-host coral Siderastrea siderea and the corallivorous snail Coralliophila abbreviata. In order to examine humans as a source and other marine invertebrates as vectors and/or reservoirs of the APS pathogen, challenge experiments were conducted with A. palmata maintained in closed aquaria to determine infectivity of strain PDR60 from reef and wastewater sources. Strain PDR60 from wastewater and diseased A. palmata caused disease signs in elkhorn coral in as little as four and five days, respectively, demonstrating that wastewater is a definitive source of APS and identifying human strain PDR60 as a coral pathogen through fulfillment of Koch's postulates. A. palmata inoculated with strain PDR60 from C. abbreviata showed limited virulence, with one of three inoculated fragments developing APS signs within 13 days. Strain PDR60 from non-host coral S. siderea showed a delayed pathogenic effect, with disease signs developing within an average of 20 days. These results suggest that C. abbreviata and non-host corals may function as reservoirs or vectors of the APS pathogen. Our results provide the first example of a marine "reverse zoonosis" involving the transmission of a human pathogen (S. marcescens to a marine invertebrate (A. palmata. These findings underscore the interaction between public health practices and environmental health indices such as coral reef survival.

  1. Genome sequence of E. coli O104:H4 leads to rapid development of a targeted antimicrobial agent against this emerging pathogen.

    Science.gov (United States)

    A recent widespread outbreak of Escherichia coli O104:H4 in Germany demonstrates the dynamic nature of emerging and re-emerging food-borne pathogens, particularly STECs and related pathogenic E. coli. Rapid genomic sequencing and public availability of these data from the German outbreak strain allo...

  2. CaPSID: A bioinformatics platform for computational pathogen sequence identification in human genomes and transcriptomes

    Directory of Open Access Journals (Sweden)

    Borozan Ivan

    2012-08-01

    Full Text Available Abstract Background It is now well established that nearly 20% of human cancers are caused by infectious agents, and the list of human oncogenic pathogens will grow in the future for a variety of cancer types. Whole tumor transcriptome and genome sequencing by next-generation sequencing technologies presents an unparalleled opportunity for pathogen detection and discovery in human tissues but requires development of new genome-wide bioinformatics tools. Results Here we present CaPSID (Computational Pathogen Sequence IDentification, a comprehensive bioinformatics platform for identifying, querying and visualizing both exogenous and endogenous pathogen nucleotide sequences in tumor genomes and transcriptomes. CaPSID includes a scalable, high performance database for data storage and a web application that integrates the genome browser JBrowse. CaPSID also provides useful metrics for sequence analysis of pre-aligned BAM files, such as gene and genome coverage, and is optimized to run efficiently on multiprocessor computers with low memory usage. Conclusions To demonstrate the usefulness and efficiency of CaPSID, we carried out a comprehensive analysis of both a simulated dataset and transcriptome samples from ovarian cancer. CaPSID correctly identified all of the human and pathogen sequences in the simulated dataset, while in the ovarian dataset CaPSID’s predictions were successfully validated in vitro.

  3. Conserved differences in protein sequence determine the human pathogenicity of Ebolaviruses

    Science.gov (United States)

    Pappalardo, Morena; Juliá, Miguel; Howard, Mark J.; Rossman, Jeremy S.; Michaelis, Martin; Wass, Mark N.

    2016-01-01

    Reston viruses are the only Ebolaviruses that are not pathogenic in humans. We analyzed 196 Ebolavirus genomes and identified specificity determining positions (SDPs) in all nine Ebolavirus proteins that distinguish Reston viruses from the four human pathogenic Ebolaviruses. A subset of these SDPs will explain the differences in human pathogenicity between Reston and the other four ebolavirus species. Structural analysis was performed to identify those SDPs that are likely to have a functional effect. This analysis revealed novel functional insights in particular for Ebolavirus proteins VP40 and VP24. The VP40 SDP P85T interferes with VP40 function by altering octamer formation. The VP40 SDP Q245P affects the structure and hydrophobic core of the protein and consequently protein function. Three VP24 SDPs (T131S, M136L, Q139R) are likely to impair VP24 binding to human karyopherin alpha5 (KPNA5) and therefore inhibition of interferon signaling. Since VP24 is critical for Ebolavirus adaptation to novel hosts, and only a few SDPs distinguish Reston virus VP24 from VP24 of other Ebolaviruses, human pathogenic Reston viruses may emerge. This is of concern since Reston viruses circulate in domestic pigs and can infect humans, possibly via airborne transmission. PMID:27009368

  4. Zoonotic Babesia: possibly emerging pathogens to be considered for tick-infested humans in Central Europe.

    Science.gov (United States)

    Hunfeld, K P; Brade, V

    2004-04-01

    The three host-tick Ixodes (I.) ricinus is regarded as an important vector of tick-borne microorganisms pathogenic for humans in central Europe and is primarily known as the main vector of Borrelia (B.) burgdorferi and the virus causing tick-borne encephalitis (TBE), the most clinically relevant tick transmitted pathogens for humans in European countries. Furthermore, it is now well established that I. ricinus also transmits Ehrlichia (E.) phagocytophila, Babesia (Ba.) divergens, and Ba. microti, all agents of zoonotic infections in dear, sheep, cattle, dogs, and horses. In addition to their known zoonotic potential, recent molecular-epidemiological and seroepidemiological surveys as well as increasingly reported clinical cases of infections caused by these tick-borne organisms other than B. burgdorferi (TOBB) also strongly suggest a possible relevance of Babesia, Ehrlichia and Rickettsia for humans at risk in Europe. However, there are few medical microbiological investigations and epidemiological data on the distribution and relevance of Babesia for humans in our part of the northern hemisphere. There is also very little diagnostic and clinical knowledge on human babesiosis in many regions of Europe. Furthermore, sophisticated diagnostic tools designed for the reliable detection of the underlying pathogens, are not yet generally available to the microbiological laboratory. This review aims to provide basic information on human babesiosis and the most relevant causative pathogens of the disease in Europe and to draw attention to this parasitic infection as a possibly emerging and probably under-diagnosed disease in this part of the northern hemisphere.

  5. Probiotic Potential of Lactobacillus Strains with Antimicrobial Activity against Some Human Pathogenic Strains

    Directory of Open Access Journals (Sweden)

    Parisa Shokryazdan

    2014-01-01

    Full Text Available The objective of this study was to isolate, identify, and characterize some lactic acid bacterial strains from human milk, infant feces, and fermented grapes and dates, as potential probiotics with antimicrobial activity against some human pathogenic strains. One hundred and forty bacterial strains were isolated and, after initial identification and a preliminary screening for acid and bile tolerance, nine of the best isolates were selected and further identified using 16 S rRNA gene sequences. The nine selected isolates were then characterized in vitro for their probiotic characteristics and their antimicrobial activities against some human pathogens. Results showed that all nine isolates belonged to the genus Lactobacillus. They were able to tolerate pH 3 for 3 h, 0.3% bile salts for 4 h, and 1.9 mg/mL pancreatic enzymes for 3 h. They exhibited good ability to attach to intestinal epithelial cells and were not resistant to the tested antibiotics. They also showed good antimicrobial activities against the tested pathogenic strains of humans, and most of them exhibited stronger antimicrobial activity than the reference strain L. casei Shirota. Thus, the nine Lactobacillus strains could be considered as potential antimicrobial probiotic strains against human pathogens and should be further studied for their human health benefits.

  6. Extraintestinal Pathogenic Escherichia coli, a Common Human Pathogen: Challenges for Vaccine Development and Progress in the Field.

    Science.gov (United States)

    Poolman, Jan T; Wacker, Michael

    2016-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) is the most common gram-negative bacterial pathogen in humans. ExPEC causes the vast majority of urinary tract infections (UTIs), is a leading cause of adult bacteremia, and is the second most common cause of neonatal meningitis. Increasing multidrug resistance among ExPEC strains constitutes a major obstacle to treatment and is implicated in increasing numbers of hospitalizations and deaths and increasing healthcare costs associated with ExPEC infections. An effective vaccine against ExPEC infection is urgently needed. The O antigen, a component of the surface lipopolysaccharide, has been identified as a promising vaccine target. With the availability of a novel bioconjugation technology it is expected that multivalent O antigen conjugate vaccines can be produced at industrial scale. Clinical proof of concept of a 4-valent O antigen conjugate vaccine is ongoing. An ExPEC vaccine effective against strains that are associated with major diseases and resistant to multiple drugs could be routinely delivered to individuals at risk of developing severe E. coli infection, such as elderly people, individuals undergoing abdominal surgery and prostatic biopsy procedures, and persons at risk of recurrent and/or complicated UTI.

  7. MYCOBACTERIUM AVIUM AS AN ACTUAL PATHOGEN OF HUMAN MYCOBACTERIOSIS

    Directory of Open Access Journals (Sweden)

    D. A. Starkova

    2013-01-01

    Full Text Available Abstract. Mycobacteriosis is an infectious disease of animals and humans caused by non-tuberculosis mycobacteria including M. avium complex. Despite the fact that the transmission of M. avium from human to human has not been proved, and mycobacteriosis has been sporadic, the number of cases of disseminated forms of disease caused by M. avium among HIV-positive patients during the last ten years was increasing. Limited knowledge about the structure of M. avium population in Russia and the lack of simple methods for the microbiological diagnosis make difficult the epidemiological monitoring of mycobacteriosis. This facilitates the use of modern, efficient molecular genetic methods for the species and subspecies identification and typing of M. avium. Thus, the detection of mobile element IS901, restriction fragment polymorphism analysis of hsp65 gene and IS1245 allow the detection and subspecies identification of M. avium. The study of genomic polymorphisms of bacterial strains for the assessment of M. avium population structure became feasible due to a complex of molecular techniques: VNTR-typing, IS1245-and IS1311-RFLP-typing.

  8. Aerially transmitted human fungal pathogens: what can we learn from metagenomics and comparative genomics?

    Science.gov (United States)

    Aliouat-Denis, Cécile-Marie; Chabé, Magali; Delhaes, Laurence; Dei-Cas, Eduardo

    2014-01-01

    In the last few decades, aerially transmitted human fungal pathogens have been increasingly recognized to impact the clinical course of chronic pulmonary diseases, such as asthma, cystic fibrosis or chronic obstructive pulmonary disease. Thanks to recent development of culture-free high-throughput sequencing methods, the metagenomic approaches are now appropriate to detect, identify and even quantify prokaryotic or eukaryotic microorganism communities inhabiting human respiratory tract and to access the complexity of even low-burden microbe communities that are likely to play a role in chronic pulmonary diseases. In this review, we explore how metagenomics and comparative genomics studies can alleviate fungal culture bottlenecks, improve our knowledge about fungal biology, lift the veil on cross-talks between host lung and fungal microbiota, and gain insights into the pathogenic impact of these aerially transmitted fungi that affect human beings. We reviewed metagenomic studies and comparative genomic analyses of carefully chosen microorganisms, and confirmed the usefulness of such approaches to better delineate biology and pathogenesis of aerially transmitted human fungal pathogens. Efforts to generate and efficiently analyze the enormous amount of data produced by such novel approaches have to be pursued, and will potentially provide the patients suffering from chronic pulmonary diseases with a better management. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

  9. Investigation on food borne diseases due to Vibrio parahaemolyticus in suburb county of Beijing from 2005 to 2011%北京市某郊区县2005年-2011年副溶血性弧菌食源性疾患调查

    Institute of Scientific and Technical Information of China (English)

    高雷

    2012-01-01

    目的:查明北京市某郊区县2005年-2011年四起食源性疾患的原因,及时有效地发现、诊断并处理食源性疾患,为制定科学的防控策略提供依据.方法:对四起事件进行现场流行病学调查,依据相关国家标准方法对所采集的62件样品进行病原学检测.结果:前三起食源性疾患均因食用被副溶血性弧菌污染且加热不充分的海鲜类食品所致.第四起食源性疾患只在病人粪便中检测出,其它样品未分离出副溶血性弧菌.从采集到的62件样品中共检测出副溶血性弧菌26株,阳性率41.9%.结论:要高度重视海鲜类食品加工安全,控制食源性致病菌的污染.同时,做好对餐饮企业的食品安全监督管理,落实餐饮企业食品留样制度,以便及时查明食源性疾患的原因.另外应加大食品安全宣传力度,提高民众预防食源性疾患的能力.%Objective:To find out the causes of four cases of food borne disease which broke out in suburb county of Beijing from 2005 to 2011. To discover, diagnose and treat food borne disease timely and effectively and to provide basis for making scientific prevention and control strategies. Methods: Epidemiological investigation was carried out on four incidents. The samples collected from scenes were tested in accordance with national standard methods. Results : Three cases of food borne disease were caused by seafood contaminated by Vibrio parahaemolyticus. In the fourth case, Vibrio parahaemolyticus were only isolated from feces. 26 strains of Vibrio parahaemolyticus were isolated from 62 samples. The positive rate was 41. 9% . Conclusion: The safety of processing seafood and the control of contamination from food borne pathogen should be given great attention. The supervision and management of catering enterprises for food safety also should be strengthened. At the same time, the food sample keeping system in food enterprises should be strictly implemented in order to find out the

  10. 食品行业中常用消毒剂对食源性单核细胞增生李斯特菌的抑菌作用研究%Bacteriostatic effect of common disinfectants in food industry to food-borne Listeria monocytogenes

    Institute of Scientific and Technical Information of China (English)

    徐冬旸; 石磊; 曾晓敏; 何建华; 闫鹤

    2013-01-01

    Objective The bacteriostatic effect of common disinfectants in food industry to Listeria monocytogenes, an important food-borne pathogenic bacteria, were investigated, to obtain more knowledge of the tolerance of Listeria monocytogenes to various disinfectants, and to provides the basis for the scientific use of disinfectant. Methods The bacterial inhibition ring test was employed to detect the bacteriostatic effect of 5 common disinfectants in food industry to a total of 73 food-borne Listeria monocytogenes isolates. Results In general use concentration, peracetic acid, iodophor and chlorhexidine do not have antibacterial effect to food-borne Listeria monocytogenes, 84 disinfection and bromogeramine have antibacterial effect. Peracetic acid has the complete bacteriostatic action with the concentration of 0.9% or higher. Chlorhexidine with the concentration of 0.5% or higher also confers complete bacteriostatic action to Listeria monocytogenes. Conclusion 84 disinfection, bromogeramine, peracetic acid with the concentration of 0.9% or higher, and chlorhexidine with the concentration of 0.5% or higher have bacteriostatic effect to food-borne Listeria monocytogenes, and thus are suitable to be applied in sterilization in the prevention and control of food-borne Listeria monocytogenes.%目的 研究食品行业中常用消毒剂对重要食源性致病菌单核细胞增生李斯特菌的抑菌效果,明确食源性单核细胞增生李斯特菌对各种消毒剂的耐受情况,为消毒剂的科学使用提供依据.方法 选取5大类食品行业常用消毒剂,采用抑菌环试验检测其对73株食源性单核细胞增生李斯特菌的抑菌效果.结果 过氧乙酸、碘伏及洗必泰在常规使用浓度下对食源性单核细胞增生李斯特菌不具备有效抑菌作用,84消毒液及新洁尔灭在常规使用浓度下具备抑菌作用,过氧乙酸浓度达0.9%及以上,洗必泰浓度达0.5%及以上时,具有完全抑菌作用.结论 对于

  11. Use of Mass-Participation Outdoor Events to Assess Human Exposure to Tickborne Pathogens.

    Science.gov (United States)

    Hall, Jessica L; Alpers, Kathrin; Bown, Kevin J; Martin, Stephen J; Birtles, Richard J

    2017-03-01

    Mapping the public health threat of tickborne pathogens requires quantification of not only the density of infected host-seeking ticks but also the rate of human exposure to these ticks. To efficiently sample a high number of persons in a short time, we used a mass-participation outdoor event. In June 2014, we sampled ≈500 persons competing in a 2-day mountain marathon run across predominantly tick-infested habitat in Scotland. From the number of tick bites recorded and prevalence of tick infection with Borrelia burgdoferi sensu lato and B. miyamotoi, we quantified the frequency of competitor exposure to the pathogens. Mass-participation outdoor events have the potential to serve as excellent windows for epidemiologic study of tickborne pathogens; their concerted use should improve spatial and temporal mapping of human exposure to infected ticks.

  12. Characterization and Identification of Two Opportunistic Human Bacterial Pathogens in Rice

    Institute of Scientific and Technical Information of China (English)

    LUO Yuan-chan; XIE Guan-lin; ZHANG Li-xin; AN Gilmyong; FANG Yuan; LUO Jin-yan; HAO Xiao-juan; ZHAO Si-feng

    2006-01-01

    Burkholderia cepacia (Bc) and Pseudomonas aeruginosa (Pa) are both biocontrol agents in agriculture and opportunistic human pathogens in hospitals. Effective management and utilization practice is needed to understand their characteristics and distribution in rice. During the last decade, the two opportunistic human pathogens were detected in 631 samples of rice seed and 117 samples of rice plant in plain, highland and mountainous rice growing areas of China. Bc and Pa were primarily differentiated by common bacteriological characteristics and pathogenic tests and then identified into species by Biolog and FAME tests. However,the genotypes of Bc still could not be distinguished. It has been noted that the Bc and Pa mainly existed in rice root with the highest distribution frequency in plain areas ( 6.1% and 16.1%) and lowest in the mountainous areas (1.0% and 7.8%).

  13. Antimicrobial activity of Uncaria tomentosa against oral human pathogens.

    Science.gov (United States)

    Ccahuana-Vasquez, Renzo Alberto; Santos, Silvana Soléo Ferreira dos; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2007-01-01

    Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria tomentosa was tested in vitro to determine the minimum inhibitory concentration (MIC) on selected microbial strains. The tested strains were oral clinical isolates of Streptococcus mutans, Staphylococcus spp., Candida albicans, Enterobacteriaceae and Pseudomonas aeruginosa. The tested concentrations of Uncaria tomentosa ranged from 0.25-5% in Müeller-Hinton agar. Three percent Uncaria tomentosa inhibited 8% of Enterobacteriaceae isolates, 52% of S. mutans and 96% of Staphylococcus spp. The tested concentrations did not present inhibitory effect on P. aeruginosa and C. albicans. It could be concluded that micropulverized Uncaria tomentosa presented antimicrobial activity on Enterobacteriaceae, S. mutans and Staphylococcus spp. isolates.

  14. The role of human movement in the transmission of vector-borne pathogens.

    Directory of Open Access Journals (Sweden)

    Steven T Stoddard

    Full Text Available BACKGROUND: Human movement is a key behavioral factor in many vector-borne disease systems because it influences exposure to vectors and thus the transmission of pathogens. Human movement transcends spatial and temporal scales with different influences on disease dynamics. Here we develop a conceptual model to evaluate the importance of variation in exposure due to individual human movements for pathogen transmission, focusing on mosquito-borne dengue virus. METHODOLOGY AND PRINCIPAL FINDINGS: We develop a model showing that the relevance of human movement at a particular scale depends on vector behavior. Focusing on the day-biting Aedes aegypti, we illustrate how vector biting behavior combined with fine-scale movements of individual humans engaged in their regular daily routine can influence transmission. Using a simple example, we estimate a transmission rate (R(0 of 1.3 when exposure is assumed to occur only in the home versus 3.75 when exposure at multiple locations--e.g., market, friend's--due to movement is considered. Movement also influences for which sites and individuals risk is greatest. For the example considered, intriguingly, our model predicts little correspondence between vector abundance in a site and estimated R(0 for that site when movement is considered. This illustrates the importance of human movement for understanding and predicting the dynamics of a disease like dengue. To encourage investigation of human movement and disease, we review methods currently available to study human movement and, based on our experience studying dengue in Peru, discuss several important questions to address when designing a study. CONCLUSIONS/SIGNIFICANCE: Human movement is a critical, understudied behavioral component underlying the transmission dynamics of many vector-borne pathogens. Understanding movement will facilitate identification of key individuals and sites in the transmission of pathogens such as dengue, which then may provide

  15. Human caspase-4 mediates noncanonical inflammasome activation against gram-negative bacterial pathogens

    Science.gov (United States)

    Casson, Cierra N.; Yu, Janet; Reyes, Valeria M.; Taschuk, Frances O.; Yadav, Anjana; Copenhaver, Alan M.; Nguyen, Hieu T.; Collman, Ronald G.; Shin, Sunny

    2015-01-01

    Inflammasomes are critical for host defense against bacterial pathogens. In murine macrophages infected by gram-negative bacteria, the canonical inflammasome activates caspase-1 to mediate pyroptotic cell death and release of IL-1 family cytokines. Additionally, a noncanonical inflammasome controlled by caspase-11 induces cell death and IL-1 release. However, humans do not encode caspase-11. Instead, humans encode two putative orthologs: caspase-4 and caspase-5. Whether either ortholog functions similar to caspase-11 is poorly defined. Therefore, we sought to define the inflammatory caspases in primary human macrophages that regulate inflammasome responses to gram-negative bacteria. We find that human macrophages activate inflammasomes specifically in response to diverse gram-negative bacterial pathogens that introduce bacterial products into the host cytosol using specialized secretion systems. In primary human macrophages, IL-1β secretion requires the caspase-1 inflammasome, whereas IL-1α release and cell death are caspase-1–independent. Instead, caspase-4 mediates IL-1α release and cell death. Our findings implicate human caspase-4 as a critical regulator of noncanonical inflammasome activation that initiates defense against bacterial pathogens in primary human macrophages. PMID:25964352

  16. Can Plant Viruses Cross the Kingdom Border and Be Pathogenic to Humans?

    Directory of Open Access Journals (Sweden)

    Fanny Balique

    2015-04-01

    Full Text Available Phytoviruses are highly prevalent in plants worldwide, including vegetables and fruits. Humans, and more generally animals, are exposed daily to these viruses, among which several are extremely stable. It is currently accepted that a strict separation exists between plant and vertebrate viruses regarding their host range and pathogenicity, and plant viruses are believed to infect only plants. Accordingly, plant viruses are not considered to present potential pathogenicity to humans and other vertebrates. Notwithstanding these beliefs, there are many examples where phytoviruses circulate and propagate in insect vectors. Several issues are raised here that question if plant viruses might further cross the kingdom barrier to cause diseases in humans. Indeed, there is close relatedness between some plant and animal viruses, and almost identical gene repertoires. Moreover, plant viruses can be detected in non-human mammals and humans samples, and there are evidence of immune responses to plant viruses in invertebrates, non-human vertebrates and humans, and of the entry of plant viruses or their genomes into non-human mammal cells and bodies after experimental exposure. Overall, the question raised here is unresolved, and several data prompt the additional extensive study of the interactions between phytoviruses and non-human mammals and humans, and the potential of these viruses to cause diseases in humans.

  17. Developing a Salivary Antibody Multiplex Immunoassay to Measure Human Exposure to Environmental Pathogens

    Science.gov (United States)

    The etiology and impacts of human exposure to environmental pathogens are of major concern worldwide and, thus, the ability to assess exposure and infections using cost effective, high-throughput approaches would be indispensable. The principal objective of this work is to devel...

  18. Draft Genome Sequence of the Animal and Human Pathogen Malassezia pachydermatis Strain CBS 1879

    NARCIS (Netherlands)

    Triana, Sergio; González, Andrés; Ohm, Robin A|info:eu-repo/dai/nl/304837628; Wosten, Han|info:eu-repo/dai/nl/120693186; de Cock, Hans|info:eu-repo/dai/nl/087737116; Restrepo, Silvia; Celis, Adriana

    2015-01-01

    Malassezia pachydermatis is a basidiomycetous yeast that causes infections in humans and animals. Here, we report the genome sequence of Malassezia pachydermatis strain CBS 1879, which will facilitate the study of mechanisms underlying pathogenicity of the only non-lipid-dependent Malasezzia

  19. Draft Genome Sequence of the Animal and Human Pathogen Malassezia pachydermatis Strain CBS 1879.

    Science.gov (United States)

    Triana, Sergio; González, Andrés; Ohm, Robin A; Wösten, Han A B; de Cock, Hans; Restrepo, Silvia; Celis, Adriana

    2015-10-15

    Malassezia pachydermatis is a basidiomycetous yeast that causes infections in humans and animals. Here, we report the genome sequence of Malassezia pachydermatis strain CBS 1879, which will facilitate the study of mechanisms underlying pathogenicity of the only non-lipid-dependent Malasezzia species. Copyright © 2015 Triana et al.

  20. Misidentification of Streptococcus uberis as a Human Pathogen: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Enea Gino Di Domenico

    2015-04-01

    Full Text Available Streptococcus uberis is an environmental bacterium responsible for bovine mastitis. It is occasionally described as a human pathogen, though in most cases the identification was based on biochemical phenotyping techniques. This report shows that the biochemical phenotyping may incorrectly identify Enterococcus faecium as S. uberis.

  1. Misidentification of Streptococcus uberis as a human pathogen: a case report and literature review.

    Science.gov (United States)

    Di Domenico, Enea Gino; Toma, Luigi; Prignano, Grazia; Pelagalli, Lorella; Police, Andrea; Cavallotti, Claudia; Torelli, Riccardo; Sanguinetti, Maurizio; Ensoli, Fabrizio

    2015-04-01

    Streptococcus uberis is an environmental bacterium responsible for bovine mastitis. It is occasionally described as a human pathogen, though in most cases the identification was based on biochemical phenotyping techniques. This report shows that the biochemical phenotyping may incorrectly identify Enterococcus faecium as S. uberis.

  2. Rhizobium pusense is the main human pathogen in the genus Agrobacterium/Rhizobium.

    Science.gov (United States)

    Aujoulat, F; Marchandin, H; Zorgniotti, I; Masnou, A; Jumas-Bilak, E

    2015-05-01

    Rhizobium pusense was recently described after isolation from the rhizosphere of chickpea. Multilocus sequence-based analysis of clinical isolates identified as Agrobacterium (Rhizobium) radiobacter demonstrated that R. pusense is the main human pathogen within Agrobacterium (Rhizobium) spp. Clinical microbiology of Agrobacterium (Rhizobium) should be considered in the light of recent taxonomic changes.

  3. The dose-response relation in human volunteers for gastro-intestinal pathogens

    NARCIS (Netherlands)

    Teunis PFM; van der Heijden OG; van der Giessen JWB; Havelaar AH; MGB

    1996-01-01

    Gepubliceerde gegevens omtrent infectie van humane proefpersonen met pathogene micro-organismen die gastro-enteritis veroorzaken (protozoa, bacterien en virussen), worden gebruikt om een kwantitatieve relatie vast te stellen tussen de ingenomen dosis en het risico op infectie. Voor alle bestudeerde

  4. Potential human pathogenic bacteria in a mixed urban watershed as revealed by pyrosequencing

    Science.gov (United States)

    Current microbial source tracking (MST) methods for water depend on testing for fecal indicator bacterial counts or specific marker gene sequences to identify fecal contamination where potential human pathogenic bacteria could be present. In this study, we applied 454 high-throughput pyrosequencing ...

  5. The arable ecosystem as battleground for emergence of new human pathogens

    NARCIS (Netherlands)

    Overbeek, van L.S.; Doorn, van J.; Wichers, J.H.; Amerongen, van A.; Roermund, van H.J.W.; Willemsen, P.T.J.

    2014-01-01

    Disease incidences related to Escherichia coli and Salmonella enterica infections by consumption of (fresh) vegetables, sprouts, and occasionally fruits made clear that these pathogens are not only transmitted to humans via the “classical” routes of meat, eggs, and dairy products, but also can be tr

  6. wKinMut-2: Identification and Interpretation of Pathogenic Variants in Human Protein Kinases

    DEFF Research Database (Denmark)

    Vazquez, Miguel; Pons, Tirso; Brunak, Søren;

    2016-01-01

    is often scattered across different sources, which makes the integrative analysis complex and laborious. wKinMut-2 constitutes a solution to facilitate the interpretation of the consequences of human protein kinase variation. Nine methods predict their pathogenicity, including a kinase-specific random...... forest approach. To understand the biological mechanisms causative of human diseases and cancer, information from pertinent reference knowledgebases and the literature is automatically mined, digested and homogenized. Variants are visualized in their structural contexts and residues affecting catalytic...

  7. wKinMut-2: Identification and Interpretation of Pathogenic Variants in Human Protein Kinases

    DEFF Research Database (Denmark)

    Vazquez, Miguel; Pons, Tirso; Brunak, Søren

    2016-01-01

    is often scattered across different sources, which makes the integrative analysis complex and laborious. wKinMut-2 constitutes a solution to facilitate the interpretation of the consequences of human protein kinase variation. Nine methods predict their pathogenicity, including a kinase-specific random...... forest approach. To understand the biological mechanisms causative of human diseases and cancer, information from pertinent reference knowledgebases and the literature is automatically mined, digested and homogenized. Variants are visualized in their structural contexts and residues affecting catalytic...

  8. Combined effect of enterocin AS-48 and high hydrostatic pressure to control food-borne pathogens inoculated in low acid fermented sausages.

    Science.gov (United States)

    Ananou, Samir; Garriga, Margarita; Jofré, Anna; Aymerich, Teresa; Gálvez, Antonio; Maqueda, Mercedes; Martínez-Bueno, Manuel; Valdivia, Eva

    2010-04-01

    The single and combined effects of enterocin AS-48 and high hydrostatic pressure (HHP) on Listeria monocytogenes, Salmonellaenterica, and Staphylococcus aureus was investigated in fuet (a low acid fermented sausage) during ripening and storage at 7 degrees C or at room temperature. AS-48 (148 AU g(-1)) caused a drastic 5.5 log cfu g(-1) decrease in L. monocytogenes (Ppressurization (400 MPa) and storage Listeria counts remained below 5 cfu g(-1) in all fuets containing AS-48 (pressurized or not). HHP alone had no anti-Listeria effect. HHP treatment significantly reduced Salmonella counts, with lowest levels in pressurized fuets with AS-48. S. aureus showed similar growth for all treatments and storage conditions. These results indicate that AS-48 can be applied alone to control L. monocytogenes and combined with HHP treatment to control Salmonella in fuets.

  9. Action mechanism of small and large molecule surfactant-based clove oil nanoemulsions against food-borne pathogens and real-time detection of their subpopulations.

    Science.gov (United States)

    Majeed, Hamid; Antoniou, John; Shoemaker, Charles F; Fang, Zhong

    2015-01-01

    Flow cytometry exactly discriminated three subpopulations, i.e., viable, damage and sublethal cells of L. monocytogenes, S. aureus and E. coli when treated at their MIC values. Purity gum ultra (PGU) a large molecule surfactant-based CO nanoemulsion exerted significant impact on cellular subpopulations of L. monocytogenes and S. aureus, with more membrane-damaged cells. On the other hand, when compared with bulk CO the results showed minimum membrane damage and more viable cells, whereas PGU CO nanoemulsion showed minimum effect on cellular subpopulation and represented more viable than damaged cells in case of E. coli. Similarly, Tween 80 a small molecule surfactant-based CO nanoemulsion showed limited overall activity against three tested microorganisms with more viable cells. We conclude that it was due to sequestration of CO constituents in interfaces, less availability in aqueous phase and finally inhibit bactericidal activity. Moreover, both CO and CO nanoemulsions showed membrane damage as primary inactivation mechanism of tested bacterial cells.

  10. Chemical composition and antioxidative activity of Echinophora platyloba DC. essential oil, and its interaction with natural antimicrobials against food-borne pathogens and spoilage organisms.

    Science.gov (United States)

    Saei-Dehkordi, S Siavash; Fallah, Aziz A; Saei-Dehkordi, S Saeid; Kousha, Sanaz

    2012-11-01

    This study was undertaken to determine the chemical composition and antioxidative capacity of Echinophora platyloba DC. essential oil, and its antimicrobial potency against Listeria monocytogenes, Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Salmonella typhimurium, Escherichia coli O157:H7, Pseudomonas aeruginosa, Candida albicans, Candida tropicalis, Rhodotorula rubra, and Rhodotorula mucilaginosa. The essential oil was analyzed by GC and GC-MS; and evaluated for its antioxidative and antimicrobial (singly or in combination with chitosan, nisin, monolaurin, or amphotericin B) activity. Thirty-three components were characterized representing 95.69% of the total oil composition in which thymol, trans-ocimene, carvacrol, and (E)-sesqui-lavandulol were the major constituents. The oil exhibited high scavenging (IC(50): 49.7 ± 2.3 μg/mL) and relative antioxidative activity (RAA%: 85.21 ± 0.4) in 1,1-diphenyl-2-picrylhydrazyl radicals and β-carotene/linoleic acid bleaching assays, respectively. The oil showed antimicrobial activity against L. monocytogenes, B. cereus, B. subtilis, S. aureus, S. typhimurium, E. coli O157:H7, P. aeruginosa, C. albicans, C. tropicalis, R. Rubra, and R. mucilaginosa. Moreover, R. mucilaginosa and P. aeruginosa were the most susceptible and most resistant organisms, respectively. Regarding the checkerboard data, 47 fractional inhibitory concentration index (FICIs) (≤ 0.5) indicated synergistic, whereas 7 FICIs (>0.5 to 1) indicated additive effect. Consequently, E. platyloba DC. essential oil could be used as a recommended natural antioxidant and antimicrobial substance for food preservation.

  11. Lactase persistence and augmented salivary alpha-amylase gene copy numbers might have been selected by the combined toxic effects of gluten and (food born) pathogens

    NARCIS (Netherlands)

    Pruimboom, Leo; Fox, Tom; Muskiet, Frits A. J.

    2014-01-01

    Various positively selected adaptations to new nutrients have been identified. Lactase persistence is among the best known, conferring the ability for drinking milk at post weaning age. An augmented number of amylase gene (AMY1) copies, giving rise to higher salivary amylase activity, has been impli

  12. Lactase persistence and augmented salivary alpha-amylase gene copy numbers might have been selected by the combined toxic effects of gluten and (food born) pathogens

    NARCIS (Netherlands)

    Pruimboom, Leo; Fox, Tom; Muskiet, Frits A. J.

    Various positively selected adaptations to new nutrients have been identified. Lactase persistence is among the best known, conferring the ability for drinking milk at post weaning age. An augmented number of amylase gene (AMY1) copies, giving rise to higher salivary amylase activity, has been

  13. Development of a novel approach for the production of dried genomic DNA for use as standards for qualitative PCR testing of food-borne pathogens

    DEFF Research Database (Denmark)

    Trapmann, S.; Catalani, P.; Hoorfar, Jeffrey

    2004-01-01

    As part of a multi-centre European project, FOOD-PCR, the feasibility of a novel approach for production of dried bacterial DNA that could be used as certified reference materials (CRM) was assessed. Selected strains of Salmonella typhimurium, Listeria monocytogenes, Escherichia coli O157...

  14. Isolation of Bacillus strains from the rhizosphere of cereals and in vitro screening for antagonism against phytopathogenic, food-borne pathogenic and spoilage micro-organisms.

    Science.gov (United States)

    Földes, T; Bánhegyi, I; Herpai, Z; Varga, L; Szigeti, J

    2000-11-01

    Bacillus strains were isolated from the rhizosphere of cereals in order to be used as natural biocontrol agents (BCAs). They were screened for antagonism in vitro against various test micro-organisms. The isolates showing antagonism were identified to species level. A combination of techniques was employed for the isolation of Bacillus species. Using the direct method, only one of the 25 isolates screened showed antagonistic properties. This strain (IFS-01) was identified by means of API test strips and the ATB Plus computer programme. It proved to be Bacillus subtilis and consequently has been designated as Bacillus subtilis IFS-01. This strain produced either a broad spectrum antimicrobial compound or several compounds with different activities. The fungi and Gram-positive bacteria were more sensitive to the antagonistic isolate than the Gram-negative bacteria. A Bacillus strain producing BCAs which can be used as biopesticides or organic preservatives has been isolated and identified.

  15. Exserohilum rostratum: characterization of a cross-kingdom pathogen of plants and humans.

    Directory of Open Access Journals (Sweden)

    Kalpana Sharma

    Full Text Available Pathogen host shifts represent a major source of new infectious diseases. There are several examples of cross-genus host jumps that have caused catastrophic epidemics in animal and plant species worldwide. Cross-kingdom jumps are rare, and are often associated with nosocomial infections. Here we provide an example of human-mediated cross-kingdom jumping of Exserohilum rostratum isolated from a patient who had received a corticosteroid injection and died of fungal meningitis in a Florida hospital in 2012. The clinical isolate of E. rostratum was compared with two plant pathogenic isolates of E. rostratum and an isolate of the closely related genus Bipolaris in terms of morphology, phylogeny, and pathogenicity on one C3 grass, Gulf annual rye grass (Lolium multiflorum, and two C4 grasses, Japanese stilt grass (Microstegium vimineum and bahia grass (Paspalum notatum. Colony growth and color, as well as conidia shape and size were the same for the clinical and plant isolates of E. rostratum, while these characteristics differed slightly for the Bipolaris sp. isolate. The plant pathogenic and clinical isolates of E. rostratum were indistinguishable based on morphology and ITS and 28S rDNA sequence analysis. The clinical isolate was as pathogenic to all grass species tested as the plant pathogenic strains that were originally isolated from plant hosts. The clinical isolate induced more severe symptoms on stilt grass than on rye grass, while this was the reverse for the plant isolates of E. rostratum. The phylogenetic similarity between the clinical and plant-associated E. rostratum isolates and the ability of the clinical isolate to infect plants suggests that a plant pathogenic strain of E. rostratum contaminated the corticosteroid injection fluid and was able to cause systemic disease in the affected patient. This is the first proof that a clinical isolate of E. rostratum is also an effective plant pathogen.

  16. Antigenic Relationships among Human Pathogenic Orientia tsutsugamushi Isolates from Thailand

    Science.gov (United States)

    Nawtaisong, Pruksa; Tanganuchitcharnchai, Ampai; Smith, Derek J.; Day, Nicholas P. J.; Paris, Daniel H.

    2016-01-01

    Background Scrub typhus is a common cause of undiagnosed febrile illness in certain tropical regions, but can be easily treated with antibiotics. The causative agent, Orientia tsutsugamushi, is antigenically variable which complicates diagnosis and efforts towards vaccine development. Methodology/Principal Findings This study aimed to dissect the antigenic and genetic relatedness of O. tsutsugamushi strains and investigate sero-diagnostic reactivities by titrating individual patient sera against their O. tsutsugamushi isolates (whole-cell antigen preparation), in homologous and heterologous serum-isolate pairs from the same endemic region in NE Thailand. The indirect immunofluorescence assay was used to titrate Orientia tsutsugamushi isolates and human sera, and a mathematical technique, antigenic cartography, was applied to these data to visualise the antigenic differences and cross-reactivity between strains and sera. No functional or antigen-specific analyses were performed. The antigenic variation found in clinical isolates was much less pronounced than the genetic differences found in the 56kDa type-specific antigen genes. The Karp-like sera were more broadly reactive than the Gilliam-like sera. Conclusions/Significance Antigenic cartography worked well with scrub typhus indirect immunofluorescence titres. The data from humoral responses suggest that a Karp-like strain would provide broader antibody cross-reactivity than a Gilliam-like strain. Although previous exposure to O. tsutsugamushi could not be ruled out, scrub typhus patient serum antibody responses were characterised by strong homologous, but weak heterologous antibody titres, with little evidence for cross-reactivity by Gilliam-like sera, but a broader response from some Karp-like sera. This work highlights the importance of antigenic variation in O. tsutsugamushi diagnosis and determination of new serotypes. PMID:27248711

  17. Antigenic Relationships among Human Pathogenic Orientia tsutsugamushi Isolates from Thailand.

    Directory of Open Access Journals (Sweden)

    Sarah L James

    2016-06-01

    Full Text Available Scrub typhus is a common cause of undiagnosed febrile illness in certain tropical regions, but can be easily treated with antibiotics. The causative agent, Orientia tsutsugamushi, is antigenically variable which complicates diagnosis and efforts towards vaccine development.This study aimed to dissect the antigenic and genetic relatedness of O. tsutsugamushi strains and investigate sero-diagnostic reactivities by titrating individual patient sera against their O. tsutsugamushi isolates (whole-cell antigen preparation, in homologous and heterologous serum-isolate pairs from the same endemic region in NE Thailand. The indirect immunofluorescence assay was used to titrate Orientia tsutsugamushi isolates and human sera, and a mathematical technique, antigenic cartography, was applied to these data to visualise the antigenic differences and cross-reactivity between strains and sera. No functional or antigen-specific analyses were performed. The antigenic variation found in clinical isolates was much less pronounced than the genetic differences found in the 56kDa type-specific antigen genes. The Karp-like sera were more broadly reactive than the Gilliam-like sera.Antigenic cartography worked well with scrub typhus indirect immunofluorescence titres. The data from humoral responses suggest that a Karp-like strain would provide broader antibody cross-reactivity than a Gilliam-like strain. Although previous exposure to O. tsutsugamushi could not be ruled out, scrub typhus patient serum antibody responses were characterised by strong homologous, but weak heterologous antibody titres, with little evidence for cross-reactivity by Gilliam-like sera, but a broader response from some Karp-like sera. This work highlights the importance of antigenic variation in O. tsutsugamushi diagnosis and determination of new serotypes.

  18. Molecular epidemiology and pathogenic potential of underdiagnosed human papillomavirus types

    Directory of Open Access Journals (Sweden)

    Sisti Stefano

    2008-07-01

    Full Text Available Abstract Background Human papillomavirus (HPV tests are crucial diagnostic tools for the prevention of neoplastic lesions of the uterine cervix. However most commercial methods are designed to detect high-risk (HR HPV types and a limited selection of low-risk ones, thus missing a fair number of intermediate/low-risk types. As a result, many HPV infections remain undiagnosed, generating distrust in virological diagnosis among gynaecologists, who continue to rely preferentially on cytological and colposcopic findings. Results In this study, we tested 6,335 consecutive clinical samples, most of them from Italian patients with cytological abnormalities. The samples, collected in 2000–2007, were analyzed using PCR amplification of a 173–206 bp (depending on HPV type conserved region in the L1 open reading frame, restriction endonuclease analysis and, where required, sequence analysis for type determination. Analysis of a smaller male sample and long term follow-up of a few female subjects was also performed. A total of 2,161 samples tested positive for HPV DNA (32.1%; 21.3% of them were mixed infections. Overall, 59 known and 2 unknown HPV types were detected. Their relative prevalence was calculated; notably, types not clearly identifiable using the most common commercial method accounted for 36% of infections. Clinical findings associated with the underdiagnosed types ranged from H-SIL to low-grade abnormalities, although none of these infections resulted in invasive cancer. Conclusion Given the high prevalence of some underdiagnosed HPV types in the population (principally HPV53, HPV66, HPV84, and HPV87 and their frequent association with cytological abnormalities, techniques capable of detecting and typing them would prove extremely useful.

  19. Bed bugs and possible transmission of human pathogens: a systematic review.

    Science.gov (United States)

    Lai, Olivia; Ho, Derek; Glick, Sharon; Jagdeo, Jared

    2016-10-01

    The global population of bed bugs (Cimex lectularius and Cimex hemipterus, family Cimicidae) has undergone a significant resurgence since the late 1990s. This is likely due to an increase in global travel, trade, and the number of insecticide-resistant bed bugs. The global bed bug population is estimated to be increasing by 100-500 % annually. The worldwide spread of bed bugs is concerning, because they are a significant socioeconomic burden and a major concern to public health. According to the United States Environmental Protection Agency, bed bugs are "a pest of significant health importance." Additionally, 68 % of U.S. pest professionals reported that bed bugs are the most challenging pest to treat. Upwards of 45 disease pathogens have been reported in bed bugs. Recent studies report that bed bugs may be competent vectors for pathogens, such as Bartonella quintana and Trypanosoma cruzi. However, public health reports have thus far failed to produce evidence that major infectious disease outbreaks have been associated with bed bugs. Since many disease pathogens have previously been reported in bed bugs and the worldwide bed bug population is now drastically increasing, it stands to reason to wonder if bed bugs might transmit human pathogens. This review includes a literature search on recently published clinical and laboratory studies (1990-2016) investigating bed bugs as potential vectors of infectious disease, and reports the significant findings and limitations of the reviewed studies. To date, no published study has demonstrated a causal relationship between bed bugs and infectious disease transmission in humans. Also, we present and propose to expand on previous hypotheses as to why bed bugs do not transmit human pathogens. Bed bugs may contain "neutralizing factors" that attenuate pathogen virulence and, thereby, decrease the ability of bed bugs to transmit infectious disease.

  20. Galleria mellonella as a model host for human pathogens: recent studies and new perspectives.

    Science.gov (United States)

    Junqueira, Juliana Campos

    2012-10-01

    The number of studies using G. mellonella as a model host for human pathogens has increased significantly in the last few years. Important studies were published from different countries for evaluating the pathogenesis of bacterial and fungal infections and for exploring the host defenses against pathogens. Therefore, standardized conditions for the use of G. melonella larvae need to be established. Recent research showed that the deprivation of G. mellonella larvae of food during the experiment caused a reduction in immune responses and an increased susceptibility to infection, suggesting that incubating of larvae in the presence or absence of nutrition may affect the results and comparisons among different laboratories.

  1. [ASSESSMENT OF POTENTIAL RISK FOR CONTAMINATION OF SURFACE WATER RESERVOIRS BY PATHOGENS OF HUMAN PARASITIC DISEASES].

    Science.gov (United States)

    Khromenkova, E P; Dimidova, L L; Dumbadze, O S; Aidinov, G T; Shendo, G L; Agirov, A Kh; Batchaev, Kh Kh

    2015-01-01

    Sanitary and parasitological studies of the waste effluents and surface reservoir waters were conducted in the south of Russia. The efficiency of purification of waste effluents from the pathogens of parasitic diseases was investigated in the region's sewage-purification facilities. The water of the surface water reservoirs was found to contain helminthic eggs and larvae and intestinal protozoan cysts because of the poor purification and disinfection of service fecal sewage waters. The poor purification and disinvasion of waste effluents in the region determine the potential risk of contamination of the surface water reservoirs and infection of the population with the pathogens of human parasitic diseases.

  2. 76 FR 30705 - Problem Formulation for Human Health Risk Assessments of Pathogens in Land-Applied Biosolids

    Science.gov (United States)

    2011-05-26

    ... AGENCY Problem Formulation for Human Health Risk Assessments of Pathogens in Land-Applied Biosolids... the availability of a final report titled, ``Problem Formulation for Human Health Risk Assessments of... health risk assessments on potential pathogens in land-applied biosolids. The document does not represent...

  3. 要重视小儿食源性疾病的防治%Paying attention to the prevention and treatment of food-borne disease in infants

    Institute of Scientific and Technical Information of China (English)

    董永绥

    2003-01-01

    @@ 1 食源性疾病的概念 1988年冬春上海市民因生食毛蚶发生31万余例甲型肝炎大流行,2002年又有南京市误食混有毒鼠强的早餐发生42例死亡、300余例中毒的悲惨事件,这两起事件都是食源性的,即食源性疾病(food-borne disease).食源性疾病是指饮水(包括饮料)和食物内含有对人体有害物质,或被微生物、寄生虫和有毒物质污染所引起的疾病[与饮水有关的又称水源性疾病(water-borne illness)].

  4. Stress responses in pathogenic Yersinia enterocolitica with reference to the stability of the virulence plasmid in food

    Science.gov (United States)

    Yersinia enterocolitica has been associated with food-borne illness, most often due the ingestion of pork products. The pathogenic effects induced by a Y. enterocolitica infection are caused by the interplay of chromosomal genes and a virulence plasmid, pYV. Generally, the plasmid is lost during g...

  5. Differences in pathogen colonization and mortality of genetically selected Japanese quail lines subjected to heat stress and Escherichia coli challenge

    Science.gov (United States)

    Japanese quail selected for divergent corticosterone response to restraint stress were evaluated for their resistance to heat stress and aerosol challenge with avian pathogenic Escherichia coli (APEC) to determine the impact of stress response on APEC pathogenesis and colonization with food-borne pa...

  6. New insight into bacterial zoonotic pathogens posing health hazards to humans

    Directory of Open Access Journals (Sweden)

    Marcin Ciszewski

    2014-12-01

    Full Text Available This article presents the problem of evolutionary changes of zoonotic pathogens responsible for human diseases. Everyone is exposed to the risk of zoonotic infection, particularly employees having direct contact with animals, i.e. veterinarians, breeders, butchers and workers of animal products’ processing industry. The article focuses on pathogens monitored by the European Centre for Disease Prevention and Control (ECDC, which has been collecting statistical data on zoonoses from all European Union countries for 19 years and publishing collected data in annual epidemiological reports. Currently, the most important 11 pathogens responsible for causing human zoonotic diseases are being monitored, of which seven are bacteria: Salmonella spp., Campylobacter spp., Listeria monocytogenes, Mycobacterium bovis, Brucella spp., Coxiella burnetti and Verotoxin- producing E. coli (VTEC / Shiga-like toxin producing E. coli (STEC. As particularly important are considered foodborne pathogens. The article also includes new emerging zoonotic bacteria, which are not currently monitored by ECDC but might pose a serious epidemiological problem in a foreseeable future: Streptococcus iniae, S. suis, S. dysgalactiae and staphylococci: Staphylococcus intermedius, S. pseudintermedius. Those species have just crossed the animal-human interspecies barrier. The exact mechanism of this phenomenon remains unknown, it is connected, however, with genetic variability, capability to survive in changing environment. These abilities derive from DNA rearrangement and horizontal gene transfer between bacterial cells. Substantial increase in the number of scientific publications on this subject, observed over the last few years, illustrates the importance of the problem. Med Pr 2014;65(6:819–829

  7. Molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans.

    Science.gov (United States)

    Zadoks, Ruth N; Middleton, John R; McDougall, Scott; Katholm, Jorgen; Schukken, Ynte H

    2011-12-01

    Mastitis, inflammation of the mammary gland, can be caused by a wide range of organisms, including gram-negative and gram-positive bacteria, mycoplasmas and algae. Many microbial species that are common causes of bovine mastitis, such as Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae and Staphylococcus aureus also occur as commensals or pathogens of humans whereas other causative species, such as Streptococcus uberis, Streptococcus dysgalactiae subsp. dysgalactiae or Staphylococcus chromogenes, are almost exclusively found in animals. A wide range of molecular typing methods have been used in the past two decades to investigate the epidemiology of bovine mastitis at the subspecies level. These include comparative typing methods that are based on electrophoretic banding patterns, library typing methods that are based on the sequence of selected genes, virulence gene arrays and whole genome sequencing projects. The strain distribution of mastitis pathogens has been investigated within individual animals and across animals, herds, countries and host species, with consideration of the mammary gland, other animal or human body sites, and environmental sources. Molecular epidemiological studies have contributed considerably to our understanding of sources, transmission routes, and prognosis for many bovine mastitis pathogens and to our understanding of mechanisms of host-adaptation and disease causation. In this review, we summarize knowledge gleaned from two decades of molecular epidemiological studies of mastitis pathogens in dairy cattle and discuss aspects of comparative relevance to human medicine.

  8. Dissection of the host-pathogen interaction in human tuberculosis using a bioengineered 3-dimensional model

    Science.gov (United States)

    Tezera, Liku B; Bielecka, Magdalena K; Chancellor, Andrew; Reichmann, Michaela T; Shammari, Basim Al; Brace, Patience; Batty, Alex; Tocheva, Annie; Jogai, Sanjay; Marshall, Ben G; Tebruegge, Marc; Jayasinghe, Suwan N; Mansour, Salah; Elkington, Paul T

    2017-01-01

    Cell biology differs between traditional cell culture and 3-dimensional (3-D) systems, and is modulated by the extracellular matrix. Experimentation in 3-D presents challenges, especially with virulent pathogens. Mycobacterium tuberculosis (Mtb) kills more humans than any other infection and is characterised by a spatially organised immune response and extracellular matrix remodelling. We developed a 3-D system incorporating virulent mycobacteria, primary human blood mononuclear cells and collagen–alginate matrix to dissect the host-pathogen interaction. Infection in 3-D led to greater cellular survival and permitted longitudinal analysis over 21 days. Key features of human tuberculosis develop, and extracellular matrix integrity favours the host over the pathogen. We optimised multiparameter readouts to study emerging therapeutic interventions: cytokine supplementation, host-directed therapy and immunoaugmentation. Each intervention modulates the host-pathogen interaction, but has both beneficial and harmful effects. This methodology has wide applicability to investigate infectious, inflammatory and neoplastic diseases and develop novel drug regimes and vaccination approaches. DOI: http://dx.doi.org/10.7554/eLife.21283.001 PMID:28063256

  9. Human pathogenic bacteria, fungi, and viruses in Drosophila: disease modeling, lessons, and shortcomings.

    Science.gov (United States)

    Panayidou, Stavria; Ioannidou, Eleni; Apidianakis, Yiorgos

    2014-02-15

    Drosophila has been the invertebrate model organism of choice for the study of innate immune responses during the past few decades. Many Drosophila-microbe interaction studies have helped to define innate immunity pathways, and significant effort has been made lately to decipher mechanisms of microbial pathogenesis. Here we catalog 68 bacterial, fungal, and viral species studied in flies, 43 of which are relevant to human health. We discuss studies of human pathogens in flies revealing not only the elicitation and avoidance of immune response but also mechanisms of tolerance, host tissue homeostasis, regeneration, and predisposition to cancer. Prominent among those is the emerging pattern of intestinal regeneration as a defense response induced by pathogenic and innocuous bacteria. Immunopathology mechanisms and many microbial virulence factors have been elucidated, but their relevance to human health conventionally necessitates validation in mammalian models of infection.

  10. Human milk blocks DC-SIGN - pathogen interaction via MUC1

    Directory of Open Access Journals (Sweden)

    Nathalie eKoning

    2015-03-01

    Full Text Available Beneficial effects of breastfeeding are well-recognized and include both immediate neonatal protection against pathogens, as well as long term protection against allergies and autoimmune diseases. Although several proteins have been identified to have anti-viral or anti-bacterial effects like secretory IgA or lactoferrin, the mechanisms of immune modulation are not fully understood. Recent studies identified important beneficial effects of glycans in human milk, such as those expressed in oligosaccharides or on glycoproteins. Glycans are recognized by the carbohydrate receptors C-type lectins on DC and specific tissue macrophages, which exert important functions in immune modulation and immune homeostasis. A well-characterized C-type lectin is DC-SIGN, which binds terminal fucose. The present study shows that in human milk, MUC1 is the major milk glycoprotein that binds to the lectin domain of DC-SIGN and prevents pathogen interaction through the presence of Lewis x-type oligosaccharides. Surprisingly, this was specific for human milk, as formula, bovine or camel milk did not show any presence of proteins that interacted with DC-SIGN. The expression of DC-SIGN is found in young infants along the entire gastro-intestinal tract. Our data thus suggest the importance of human milk glycoproteins for blocking pathogen interaction to DC in young children. Moreover, a potential benefit of human milk later in life in shaping the infants immune system through DC-SIGN cannot be ruled out.

  11. Assessing microbial decontamination of indoor air with particular focus on human pathogenic viruses.

    Science.gov (United States)

    Duchaine, Caroline

    2016-09-01

    Transmission of bacterial, fungal, and viral pathogens is of primary importance in public and occupational health and infection control. Although several standardized protocols have been proposed to target microbes on fomites through surface decontamination, use of microbicidal agents, and cleaning processes, only limited guidance is available on microbial decontamination of indoor air to reduce the risk of pathogen transmission between individuals. This article reviews the salient aspects of airborne transmission of infectious agents, exposure assessment, in vitro assessment of microbicidal agents, and processes for air decontamination for infection prevention and control. Laboratory-scale testing (eg, rotating chambers, wind tunnels) and promising field-scale methodologies to decontaminate indoor air are also presented. The potential of bacteriophages as potential surrogates for the study of airborne human pathogenic viruses is also discussed.

  12. Phage display-based strategies for cloning and optimization of monoclonal antibodies directed against human pathogens.

    Science.gov (United States)

    Clementi, Nicola; Mancini, Nicasio; Solforosi, Laura; Castelli, Matteo; Clementi, Massimo; Burioni, Roberto

    2012-01-01

    In the last two decades, several phage display-selected monoclonal antibodies (mAbs) have been described in the literature and a few of them have managed to reach the clinics. Among these, the anti-respiratory syncytial virus (RSV) Palivizumab, a phage-display optimized mAb, is the only marketed mAb directed against microbial pathogens. Palivizumab is a clear example of the importance of choosing the most appropriate strategy when selecting or optimizing an anti-infectious mAb. From this perspective, the extreme versatility of phage-display technology makes it a useful tool when setting up different strategies for the selection of mAbs directed against human pathogens, especially when their possible clinical use is considered. In this paper, we review the principal phage display strategies used to select anti-infectious mAbs, with particular attention focused on those used against hypervariable pathogens, such as HCV and influenza viruses.

  13. UV Light Inactivation of Human and Plant Pathogens in Unfiltered Surface Irrigation Water

    Science.gov (United States)

    Jones, Lisa A.; Worobo, Randy W.

    2014-01-01

    Fruit and vegetable growers continually battle plant diseases and food safety concerns. Surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. Treatment methods for surface water are currently limited, and there is a need for suitable treatment options. A liquid-processing unit that uses UV light for the decontamination of turbid juices was analyzed for its efficacy in the treatment of surface waters contaminated with bacterial or oomycete pathogens, i.e., Escherichia coli, Salmonella enterica, Listeria monocytogenes, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, and Phytophthora capsici. Five-strain cocktails of each pathogen, containing approximately 108 or 109 CFU/liter for bacteria or 104 or 105 zoospores/liter for Ph. capsici, were inoculated into aliquots of two turbid surface water irrigation sources and processed with the UV unit. Pathogens were enumerated before and after treatment. In general, as the turbidity of the water source increased, the effectiveness of the UV treatment decreased, but in all cases, 99.9% or higher inactivation was achieved. Log reductions ranged from 10.0 to 6.1 and from 5.0 to 4.2 for bacterial pathogens and Ph. capsici, respectively. PMID:24242253

  14. UV light inactivation of human and plant pathogens in unfiltered surface irrigation water.

    Science.gov (United States)

    Jones, Lisa A; Worobo, Randy W; Smart, Christine D

    2014-02-01

    Fruit and vegetable growers continually battle plant diseases and food safety concerns. Surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. Treatment methods for surface water are currently limited, and there is a need for suitable treatment options. A liquid-processing unit that uses UV light for the decontamination of turbid juices was analyzed for its efficacy in the treatment of surface waters contaminated with bacterial or oomycete pathogens, i.e., Escherichia coli, Salmonella enterica, Listeria monocytogenes, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, and Phytophthora capsici. Five-strain cocktails of each pathogen, containing approximately 10(8) or 10(9) CFU/liter for bacteria or 10(4) or 10(5) zoospores/liter for Ph. capsici, were inoculated into aliquots of two turbid surface water irrigation sources and processed with the UV unit. Pathogens were enumerated before and after treatment. In general, as the turbidity of the water source increased, the effectiveness of the UV treatment decreased, but in all cases, 99.9% or higher inactivation was achieved. Log reductions ranged from 10.0 to 6.1 and from 5.0 to 4.2 for bacterial pathogens and Ph. capsici, respectively.

  15. Identification of tick-borne pathogens in ticks feeding on humans in Turkey.

    Directory of Open Access Journals (Sweden)

    Ömer Orkun

    2014-08-01

    Full Text Available The importance of tick-borne diseases is increasing all over the world, including Turkey. The tick-borne disease outbreaks reported in recent years and the abundance of tick species and the existence of suitable habitats increase the importance of studies related to the epidemiology of ticks and tick-borne pathogens in Turkey. The aim of this study was to investigate the presence of and to determine the infection rates of some tick-borne pathogens, including Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in the ticks removed from humans in different parts of Ankara.A total of 169 ticks belonging to the genus Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus were collected by removing from humans in different parts of Ankara. Ticks were molecularly screened for Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae by PCR and sequencing analysis. We detected 4 Babesia spp.; B. crassa, B. major, B. occultans and B. rossi, one Borrelia spp.; B. burgdorferi sensu stricto and 3 spotted fever group rickettsiae; R. aeschlimannii, R. slovaca and R. hoogstraalii in the tick specimens analyzed. This is the report showing the presence of B. rossi in a region that is out of Africa and in the host species Ha. parva. In addition, B. crassa, for which limited information is available on its distribution and vector species, and B. occultans, for which no conclusive information is available on its presence in Turkey, were identified in Ha. parva and H. marginatum, respectively. Two human pathogenic rickettsia species (R. aeschlimannii and R. slovaca were detected with a high prevalence in ticks. Additionally, B. burgdorferi sensu stricto was detected in unusual tick species (H. marginatum, H. excavatum, Hyalomma spp. (nymph and Ha. parva.This study investigates both the distribution of several tick-borne pathogens affecting humans and animals, and the presence of new tick-borne pathogens in Turkey

  16. Identification of tick-borne pathogens in ticks feeding on humans in Turkey.

    Science.gov (United States)

    Orkun, Ömer; Karaer, Zafer; Çakmak, Ayşe; Nalbantoğlu, Serpil

    2014-08-01

    The importance of tick-borne diseases is increasing all over the world, including Turkey. The tick-borne disease outbreaks reported in recent years and the abundance of tick species and the existence of suitable habitats increase the importance of studies related to the epidemiology of ticks and tick-borne pathogens in Turkey. The aim of this study was to investigate the presence of and to determine the infection rates of some tick-borne pathogens, including Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in the ticks removed from humans in different parts of Ankara. A total of 169 ticks belonging to the genus Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus were collected by removing from humans in different parts of Ankara. Ticks were molecularly screened for Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae by PCR and sequencing analysis. We detected 4 Babesia spp.; B. crassa, B. major, B. occultans and B. rossi, one Borrelia spp.; B. burgdorferi sensu stricto and 3 spotted fever group rickettsiae; R. aeschlimannii, R. slovaca and R. hoogstraalii in the tick specimens analyzed. This is the report showing the presence of B. rossi in a region that is out of Africa and in the host species Ha. parva. In addition, B. crassa, for which limited information is available on its distribution and vector species, and B. occultans, for which no conclusive information is available on its presence in Turkey, were identified in Ha. parva and H. marginatum, respectively. Two human pathogenic rickettsia species (R. aeschlimannii and R. slovaca) were detected with a high prevalence in ticks. Additionally, B. burgdorferi sensu stricto was detected in unusual tick species (H. marginatum, H. excavatum, Hyalomma spp. (nymph) and Ha. parva). This study investigates both the distribution of several tick-borne pathogens affecting humans and animals, and the presence of new tick-borne pathogens in Turkey. More

  17. Horizontal gene transfers link a human MRSA pathogen to contagious bovine mastitis bacteria.

    Directory of Open Access Journals (Sweden)

    Thomas Brody

    Full Text Available BACKGROUND: Acquisition of virulence factors and antibiotic resistance by many clinically important bacteria can be traced to horizontal gene transfer (HGT between related or evolutionarily distant microflora. Comparative genomic analysis has become an important tool for identifying HGT DNA in emerging pathogens. We have adapted the multi-genome alignment tool EvoPrinter to facilitate discovery of HGT DNA sequences within bacterial genomes and within their mobile genetic elements. PRINCIPAL FINDINGS: EvoPrinter analysis of 13 different Staphylococcus aureus genomes revealed that one of the human isolates, the hospital epidemic methicillin-resistant MRSA252 strain, uniquely shares multiple putative HGT DNA sequences with different causative agents of bovine mastitis that are not found in the other human S. aureus isolates. MRSA252 shares over 14 different DNA sequence blocks with the bovine mastitis ET3 S. aureus strain RF122, and many of the HGT DNAs encode virulence factors. EvoPrinter analysis of the MRSA252 chromosome also uncovered virulence-factor encoding HGT events with the genome of Listeria monocytogenes and a Staphylococcus saprophyticus associated plasmid. Both bacteria are also causal agents of contagious bovine mastitis. CONCLUSIONS: EvoPrinter analysis reveals that the human MRSA252 strain uniquely shares multiple DNA sequence blocks with different causative agents of bovine mastitis, suggesting that HGT events may be occurring between these pathogens. These findings have important implications with regard to animal husbandry practices that inadvertently enhance the contact of human and livestock bacterial pathogens.

  18. Signatures of environmental genetic adaptation pinpoint pathogens as the main selective pressure through human evolution.

    Science.gov (United States)

    Fumagalli, Matteo; Sironi, Manuela; Pozzoli, Uberto; Ferrer-Admetlla, Anna; Ferrer-Admettla, Anna; Pattini, Linda; Nielsen, Rasmus

    2011-11-01

    Previous genome-wide scans of positive natural selection in humans have identified a number of non-neutrally evolving genes that play important roles in skin pigmentation, metabolism, or immune function. Recent studies have also shown that a genome-wide pattern of local adaptation can be detected by identifying correlations between patterns of allele frequencies and environmental variables. Despite these observations, the degree to which natural selection is primarily driven by adaptation to local environments, and the role of pathogens or other ecological factors as selective agents, is still under debate. To address this issue, we correlated the spatial allele frequency distribution of a large sample of SNPs from 55 distinct human populations to a set of environmental factors that describe local geographical features such as climate, diet regimes, and pathogen loads. In concordance with previous studies, we detected a significant enrichment of genic SNPs, and particularly non-synonymous SNPs associated with local adaptation. Furthermore, we show that the diversity of the local pathogenic environment is the predominant driver of local adaptation, and that climate, at least as measured here, only plays a relatively minor role. While background demography by far makes the strongest contribution in explaining the genetic variance among populations, we detected about 100 genes which show an unexpectedly strong correlation between allele frequencies and pathogenic environment, after correcting for demography. Conversely, for diet regimes and climatic conditions, no genes show a similar correlation between the environmental factor and allele frequencies. This result is validated using low-coverage sequencing data for multiple populations. Among the loci targeted by pathogen-driven selection, we found an enrichment of genes associated to autoimmune diseases, such as celiac disease, type 1 diabetes, and multiples sclerosis, which lends credence to the hypothesis that some

  19. Signatures of environmental genetic adaptation pinpoint pathogens as the main selective pressure through human evolution.

    Directory of Open Access Journals (Sweden)

    Matteo Fumagalli

    2011-11-01

    Full Text Available Previous genome-wide scans of positive natural selection in humans have identified a number of non-neutrally evolving genes that play important roles in skin pigmentation, metabolism, or immune function. Recent studies have also shown that a genome-wide pattern of local adaptation can be detected by identifying correlations between patterns of allele frequencies and environmental variables. Despite these observations, the degree to which natural selection is primarily driven by adaptation to local environments, and the role of pathogens or other ecological factors as selective agents, is still under debate. To address this issue, we correlated the spatial allele frequency distribution of a large sample of SNPs from 55 distinct human populations to a set of environmental factors that describe local geographical features such as climate, diet regimes, and pathogen loads. In concordance with previous studies, we detected a significant enrichment of genic SNPs, and particularly non-synonymous SNPs associated with local adaptation. Furthermore, we show that the diversity of the local pathogenic environment is the predominant driver of local adaptation, and that climate, at least as measured here, only plays a relatively minor role. While background demography by far makes the strongest contribution in explaining the genetic variance among populations, we detected about 100 genes which show an unexpectedly strong correlation between allele frequencies and pathogenic environment, after correcting for demography. Conversely, for diet regimes and climatic conditions, no genes show a similar correlation between the environmental factor and allele frequencies. This result is validated using low-coverage sequencing data for multiple populations. Among the loci targeted by pathogen-driven selection, we found an enrichment of genes associated to autoimmune diseases, such as celiac disease, type 1 diabetes, and multiples sclerosis, which lends credence to the

  20. Oral pathogens change proliferation properties of oral tumor cells by affecting gene expression of human defensins.

    Science.gov (United States)

    Hoppe, T; Kraus, D; Novak, N; Probstmeier, R; Frentzen, M; Wenghoefer, M; Jepsen, S; Winter, J

    2016-10-01

    The impact of oral pathogens onto the generation and variability of oral tumors has only recently been investigated. To get further insights, oral cancer cells were treated with pathogens and additionally, as a result of this bacterial cellular infection, with human defensins, which are as anti-microbial peptide members of the innate immune system. After cell stimulation, proliferation behavior, expression analysis of oncogenic relevant defensin genes, and effects on EGFR signaling were investigated. The expression of oncogenic relevant anti-microbial peptides was analyzed with real-time PCR and immunohistochemistry. Cell culture experiments were performed to examine cellular impacts caused by stimulation, i.e., altered gene expression, proliferation rate, and EGF receptor-dependent signaling. Incubation of oral tumor cells with an oral pathogen (Porphyromonas gingivalis) and human α-defensins led to an increase in cell proliferation. In contrast, another oral bacterium used, Aggregatibacter actinomycetemcomitans, enhanced cell death. The bacteria and anti-microbial peptides exhibited diverse effects on the transcript levels of oncogenic relevant defensin genes and epidermal growth factor receptor signaling. These two oral pathogens exhibited opposite primary effects on the proliferation behavior of oral tumor cells. Nevertheless, both microbe species led to similar secondary impacts on the proliferation rate by modifying expression levels of oncogenic relevant α-defensin genes. In this respect, oral pathogens exerted multiplying effects on tumor cell proliferation. Additionally, human defensins were shown to differently influence epidermal growth factor receptor signaling, supporting the hypothesis that these anti-microbial peptides serve as ligands of EGFR, thus modifying the proliferation behavior of oral tumor cells.

  1. Phlebotomine sand fly-borne pathogens in the Mediterranean Basin: Human leishmaniasis and phlebovirus infections.

    Science.gov (United States)

    Moriconi, Martina; Rugna, Gianluca; Calzolari, Mattia; Bellini, Romeo; Albieri, Alessandro; Angelini, Paola; Cagarelli, Roberto; Landini, Maria P; Charrel, Remi N; Varani, Stefania

    2017-08-01

    Pathogens transmitted to humans by phlebotomine sand flies are neglected, as they cause infectious diseases that are not on the priority list of national and international public health systems. However, the infections caused by protozoa of the Leishmania genus and viruses belonging to the Phlebovirus genus (family Phenuiviridae)-the most significant group of viruses transmitted by sand flies-have a relevant role for human pathology. These infections are emerging in the Mediterranean region and will likely spread in forthcoming decades, posing a complex threat to human health. Four species and 2 hybrid strains of Leishmania are pathogenic for humans in the Mediterranean Basin, with an estimated annual incidence of 239,500-393,600 cases of cutaneous leishmaniasis and 1,200-2,000 cases of visceral leishmaniasis. Among the phleboviruses, Toscana virus can cause neuroinvasive infections, while other phleboviruses are responsible for a typical "3-day fever"; the actual incidence of Phlebovirus infections in the Mediterranean area is unknown, although at least 250 million people are exposed. Here, we reviewed the current literature on epidemiology of sand fly-borne infections in the Mediterranean Basin, with a focus on humans. Our analysis indicates the need for increased public health activities directed to determine the disease burden of these infections as well as to improve their surveillance. Among the emerging challenges concerning sand fly-borne pathogens, the relationships between sand fly-borne protozoa and viruses should be considered in future studies, including epidemiological links between Leishmania and phleboviruses as well as the conditional capacity for these pathogens to be involved in interactions that may evolve towards increased virulence.

  2. Identification and analysis of cation channel homologues in human pathogenic fungi.

    Directory of Open Access Journals (Sweden)

    David L Prole

    Full Text Available Fungi are major causes of human, animal and plant disease. Human fungal infections can be fatal, but there are limited options for therapy, and resistance to commonly used anti-fungal drugs is widespread. The genomes of many fungi have recently been sequenced, allowing identification of proteins that may become targets for novel therapies. We examined the genomes of human fungal pathogens for genes encoding homologues of cation channels, which are prominent drug targets. Many of the fungal genomes examined contain genes encoding homologues of potassium (K(+, calcium (Ca(2+ and transient receptor potential (Trp channels, but not sodium (Na(+ channels or ligand-gated channels. Some fungal genomes contain multiple genes encoding homologues of K(+ and Trp channel subunits, and genes encoding novel homologues of voltage-gated K(v channel subunits are found in Cryptococcus spp. Only a single gene encoding a homologue of a plasma membrane Ca(2+ channel was identified in the genome of each pathogenic fungus examined. These homologues are similar to the Cch1 Ca(2+ channel of Saccharomyces cerevisiae. The genomes of Aspergillus spp. and Cryptococcus spp., but not those of S. cerevisiae or the other pathogenic fungi examined, also encode homologues of the mitochondrial Ca(2+ uniporter (MCU. In contrast to humans, which express many K(+, Ca(2+ and Trp channels, the genomes of pathogenic fungi encode only very small numbers of K(+, Ca(2+ and Trp channel homologues. Furthermore, the sequences of fungal K(+, Ca(2+, Trp and MCU channels differ from those of human channels in regions that suggest differences in regulation and susceptibility to drugs.

  3. Human and Pathogen Factors Associated with Chlamydia trachomatis-Related Infertility in Women

    Science.gov (United States)

    Menon, S.; Timms, P.; Allan, J. A.; Alexander, K.; Rombauts, L.; Horner, P.; Keltz, M.; Hocking, J.

    2015-01-01

    SUMMARY Chlamydia trachomatis is the most common bacterial sexually transmitted pathogen worldwide. Infection can result in serious reproductive pathologies, including pelvic inflammatory disease, ectopic pregnancy, and infertility, in women. However, the processes that result in these reproductive pathologies have not been well defined. Here we review the evidence for the human disease burden of these chlamydial reproductive pathologies. We then review human-based evidence that links Chlamydia with reproductive pathologies in women. We present data supporting the idea that host, immunological, epidemiological, and pathogen factors may all contribute to the development of infertility. Specifically, we review the existing evidence that host and pathogen genotypes, host hormone status, age of sexual debut, sexual behavior, coinfections, and repeat infections are all likely to be contributory factors in development of infertility. Pathogen factors such as infectious burden, treatment failure, and tissue tropisms or ascension capacity are also potential contributory factors. We present four possible processes of pathology development and how these processes are supported by the published data. We highlight the limitations of the evidence and propose future studies that could improve our understanding of how chlamydial infertility in women occurs and possible future interventions to reduce this disease burden. PMID:26310245

  4. [Human plague and pneumonic plague : pathogenicity, epidemiology, clinical presentations and therapy].

    Science.gov (United States)

    Riehm, Julia M; Löscher, Thomas

    2015-07-01

    Yersinia pestis is a highly pathogenic gram-negative bacterium and the causative agent of human plague. In the last 1500 years and during three dreaded pandemics, millions of people became victims of Justinian's plague, the Black Death, or modern plague. Today, Y. pestis is endemic in natural foci of Asian, African and American countries. Due to its broad dissemination in mammal species and fleas, eradication of the pathogen will not be possible in the near future. In fact, plague is currently classified as a "re-emerging disease". Infection may occur after the bite of an infected flea, but also after oral ingestion or inhalation of the pathogen. The clinical presentations comprise the bubonic and pneumonic form, septicemia, rarely pharyngitis, and meningitis. Most human cases can successfully be treated with antibiotics. However, the high transmission rate and lethality of pneumonic plague require international and mandatory case notification and quarantine of patients. Rapid diagnosis, therapy and barrier nursing are not only crucial for the individual patient but also for the prevention of further spread of the pathogen or of epidemics. Therefore, WHO emergency schedules demand the isolation of cases, identification and surveillance of contacts as well as control of zoonotic reservoir animals and vectors. These sanctions and effective antibiotic treatment usually allow a rapid containment of outbreaks. However, multiple antibiotic resistant strains of Y. pestis have been isolated from patients in the past. So far, no outbreaks with such strains have been reported.

  5. Leptospira wolffii, a potential new pathogenic Leptospira species detected in human, sheep and dog.

    Science.gov (United States)

    Zakeri, Sedigheh; Khorami, Nargess; Ganji, Zahra F; Sepahian, Neda; Malmasi, Abdol-Ali; Gouya, Mohammad Mehdi; Djadid, Navid D

    2010-03-01

    Leptospirosis is the most common zoonotic disease, which is transmitted to humans through contaminated water or direct exposure to the urine of infected animals. In this study, the presence and prevalence of Leptospira species in the infected samples of human (n=369) and sheep (n=75) sera and also dogs' urine (n=150), collected from four provinces of Iran, were investigated by using nested-PCR/RFLP assay followed by sequencing analysis. Nested-PCR assay detected that 98/369 (26.5%) human, 13/75 (17.33%) of sheep's sera and 33/150 (22%) dogs' urine samples were positive for Leptospira DNA. RFLP assay detected that all positive cases had either pathogenic or intermediate Leptospira species. By sequence analysis, Leptospira interrogans was the most prevalent species among the examined samples of human (53/82, 64.6%) and sheep (11/13, 84.6%). However, in dog samples, Leptospira wolffii (27/29, 93.1%) was detected for the first time and was the dominant species. The presence of L. wolffii with 100% identity in clinical human samples and animals suspected with Leptospira may provide evidence for circulation of L. wolffii and its role in transmission cycle within human and animal hosts. In addition, this species can be potentially pathogenic to human and probably animal hosts. A large epidemiology survey would be needed to define the presence and the prevalence of this species in global endemic regions.

  6. 食源性大肠杆菌的PCR检测%PCR Detection of Food-borne E.coli

    Institute of Scientific and Technical Information of China (English)

    席美丽; 只帅; 王小璞; 杨保伟; 王新

    2011-01-01

    In order to apply PCR technology in the food safety, a multiple PCR protocol was developed to detect pathogenic E. Coli in food. Primers for uidA and seven virulence genes were designed, and the detection limit of E. Coli were determined in artificially contaminated water and milk using general PCR and real-time PCR. It was demonstrated that two multiple PCRs can identify seven virulence gene and uidA gene for pathogenic E. Coli. The detection limits of general PCR and real-time PCR test were the same: for artificially contaminated water, the detection limit was 2. 8 X 102 cfu/mL; for contaminated milk, the detection limit was 2. 8 X 104 cfu/mL.%为了将PCR技术更好地应用于食品安全检测,利用多重PCR对大肠杆菌uidA基因和7种毒理基因进行扩增,并对人为污染大肠杆菌的水和牛奶进行普通和实时定量PCR限度检测.结果发现,2组多重PCR反应即可完成uidA和7种毒理基因的检测;普通PCR和实时定量PCR检测限度相同,对人为污染水检测限度为2.8×102 cfu/mL,对人为污染牛奶的检测限度为2.8×104 cfu/mL.

  7. Role of Non-coding Regulatory RNA in the Virulence of Human Pathogenic Vibrios

    Science.gov (United States)

    Pérez-Reytor, Diliana; Plaza, Nicolás; Espejo, Romilio T.; Navarrete, Paola; Bastías, Roberto; Garcia, Katherine

    2017-01-01

    In recent decades, the identification of small non-coding RNAs in bacteria has revealed an important regulatory mechanism of gene expression involved in the response to environmental signals and to the control of virulence. In the family Vibrionaceae, which includes several human and animal pathogens, small non-coding RNAs (sRNAs) are closely related to important processes including metabolism, quorum sensing, virulence, and fitness. Studies conducted in silico and experiments using microarrays and high-throughput RNA sequencing have led to the discovery of an unexpected number of sRNAs in Vibrios. The present review discusses the most relevant reports regarding the mechanisms of action of sRNAs and their implications in the virulence of the main human pathogens