RESUMO
Vibriosis, an illness caused by the Vibrio bacteria species, results in significant economic loss in olive flounder farms. Here we present a novel anti-Vibrio feed vaccine protecting multiple strains of Vibrio pathogens, a universal vaccine effect. The vaccine was generated by engineering Lactococcus lactis BFE920 to express the fusion antigens of Vibrio outer membrane protein K (OmpK) and flagellin B subunit (FlaB). These antigen genes are highly conserved among Vibrio species. Olive flounder (7.1 ± 0.8 g and 140 ± 10 g) were fed the vaccine adsorbed to a regular feed (1 × 107 CFU/g) for one week with a 1-week interval, repeating three times (a triple boost). The vaccinated fish increased the significant levels of antigen-specific antibodies, T cell numbers (CD4-1, CD4-2, and CD8α), cytokine production (T-bet and IFN-γ), and innate immune responses (TLR5M, IL-1ß, and IL-12p40). Also, the survival rates of adult and juvenile fish fed the vaccine were significantly elevated when challenged with V. anguillarum, V. alginolyticus, and V. harveyi. In addition, weight gain rate and feed conversion ratio were improved in vaccinated fish. The feed vaccine protected multiple Vibrio pathogens, a universal vaccine effect, by activating innate and adaptive immune responses. This oral vaccine may be developed as an anti-Vibrio vaccine to protect against a broad spectrum of Vibrio pathogens.
Assuntos
Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Linguado , Lactococcus lactis/metabolismo , Vibrioses/veterinária , Vibrio/metabolismo , Imunidade Adaptativa , Animais , Vacinas Bacterianas/administração & dosagem , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Imunidade Inata , Probióticos , Vibrio/imunologia , Vibrioses/prevenção & controleRESUMO
IL-12 is an important cytokine that connects the innate and adaptive immune systems. The complete gene structure of olive flounder IL-12 and its characteristics have not yet been formally reported. Here, we report the complete sequences of both subunits of olive flounder IL-12 (IL-12p35 and IL-12p40). In addition, its function was analyzed by generating the single-chain rIL-12 of which subunits were fused by a GS linker and the rIL-12-specific mouse antibody. The cDNA sequences of IL-12p35 and IL-12p40 were 1059 nucleotides and 1319 nucleotides, respectively. The analyses of their gene structures, deduced amino acid sequences, protein model structures, and phylogenetic trees confirmed the accurate identification of olive flounder IL-12. The protein structure model suggested that an inter-subunit disulfide bond might be formed between the Cys177 of p35 and Cys74 of p40 to link the subunits. Olive flounder expressed IL-12p40 at higher levels than IL-12p35 in the various tissues under natural conditions although both expression levels were low. However, when infected by Edwardsiella tarda or stimulated by LPS, the flounder expressed both of the subunit genes at similar maximized levels in 6â¯h and gradually reduced thereafter. Olive flounder PBMC induced with the rIL-12 increased IFN-γ and TNF-α expression but decreased IL-10 expression as did treatment with LPS. However, when the LPS-treated PBMC were neutralized with the rIL-12-specific antibody, the pattern of cytokine expression was precisely reversed. In conclusion, we have formally identified the gene structure and function of olive flounder IL-12.
Assuntos
Imunidade Adaptativa/genética , Doenças dos Peixes/imunologia , Linguados/genética , Linguados/imunologia , Imunidade Inata/genética , Interleucina-12/genética , Interleucina-12/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Edwardsiella tarda/fisiologia , Infecções por Enterobacteriaceae/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Linguado/genética , Linguado/imunologia , Perfilação da Expressão Gênica/veterinária , Interleucina-12/química , Lipopolissacarídeos/farmacologia , Filogenia , Alinhamento de Sequência/veterináriaRESUMO
A number of makgeolli (Korean traditional turbid rice wine) products are commercially available in various forms. To date, there has been no comprehensive investigation of these products. Here, we collected samples of almost all of the makgeolli products that are currently commercially available (nâ¯=â¯167), recorded their manufacturing variables, and examined physiochemical parameters and microbial communities, using quantitative and qualitative methods. The aerobic plate count (APC) and counts of lactic acid bacteria (LAB), acetic acid bacteria (AAB), fungi, total coliforms, and Bacillus cereus were obtained, and the presence of Escherichia coli and eight foodborne pathogens was also examined. The data obtained were segmented and analyzed based on multiple variables associated with the manufacturing characteristics. Despite high ethanol contents (up to 16.0%) and high acidities (pH 3.3-4.5), the rice wine products examined here had diverse and abundant microbiotas (mean values: APC, 5.3; LAB,4.4; AAB,1.5; fungi, 3.8 log CFU/ml). In particular, LAB and fungi, which are used as co-starter cultures during rice wine manufacturing, accounted for the majority of the microbiotas. Bivariate analyses revealed significant positive correlations between the individual micro-organism counts (Pearson correlation coefficientâ¯=â¯0.668-0.947). Among the manufacturing variables considered in this study, only the pasteurization status had a significant effect on the microbial communities of rice wine products (pâ¯<â¯0.05). When examining the presence of foodborne pathogens, B. cereus was isolated from some of the rice wine products (58.1%) at low levels (<100â¯CFU/ml), and its detection rate was not significantly lower in the pasteurized products than the raw products. Overall, the results presented here provide a comprehensive overview of the microbiotas of commercially available turbid rice wines and their relationships to manufacturing variables. These data will help to direct future studies focusing on rice wine quality and safety control measures.
Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Fungos/isolamento & purificação , Oryza/microbiologia , Vinho/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Qualidade de Produtos para o Consumidor , Etanol/análise , Etanol/metabolismo , Fermentação , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Concentração de Íons de Hidrogênio , Análise Multivariada , Oryza/química , República da Coreia , Vinho/análiseRESUMO
Edwardsiellosis is a major fish disease that causes a significant economic damage in the aquaculture industry. Here, we assessed vaccine efficacy after feeding oral vaccines to olive flounder (Paralichthys olivaceus), either L. lactis BFE920 expressing Edwardsiella tarda outer membrane protein A (OmpA), flagellar hook protein D (FlgD), or a fusion antigen of the two. Feed vaccination was done twice with a one-week interval. Fish were fed regular feed adsorbed with the vaccines. Feed vaccination was given over the course of one week to maximize the interaction between the feed vaccines and the fish intestine. Flounder fed the vaccine containing the fusion antigen had significantly elevated levels T cell genes (CD4-1, CD4-2, and CD8α), type 1 helper T cell (Th1) subset indicator genes (T-bet and IFN-γ), and antigen-specific antibodies compared to the groups fed the single antigen-expressing vaccines. Furthermore, the superiority of the fusion vaccine was also observed in survival rates when fish were challenged with E. tarda: OmpA-FlgD-expressing vaccine (82.5% survival); FlgD-vaccine (55.0%); OmpA-vaccine (50%); WT L. lactis BFE920 (37.5%); Ctrl (10%). In addition, vaccine-fed fish exhibited increased weight gain (â¼20%) and a decreased feed conversion ratio (â¼20%) during the four week vaccination period. Flounder fed the FlgD-expressing vaccine, either the single or the fusion form, had significantly increased expression of TLR5M, IL-1ß, and IL-12p40, suggesting that the FlgD may be a ligand of olive flounder TLR5M receptor or closely related to the TLR5M pathway. In conclusion, the present study demonstrated that olive flounder fed L. lactis BFE920 expressing a fusion antigen composed of E. tarda OmpA and FlgD showed a strong protective effect against edwardsiellosis indicating this may be developed as an E. tarda feed vaccine.
Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Edwardsiella tarda/imunologia , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/prevenção & controle , Linguados , Lactococcus lactis/imunologia , Animais , Proteínas da Membrana Bacteriana Externa/imunologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Proteínas de Escherichia coli/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Fusão de Membrana/imunologiaRESUMO
BACKGROUND: The present study examined the changes in microbiological composition during the production process of crab marinated in soy sauce, potential microbial hazards, potential contamination routes and effective critical control points. Crab and soy sauce samples were obtained from six different manufacturing plants at different stages, and their microbiological content was comprehensively assessed by quantitative and qualitative analyses. RESULTS: The results revealed the following: (1) the final products contained 4.0 log colony-forming units (CFU) g-1 aerobic plate counts (APCs) and 1.1 log CFU g-1 coliforms, which may have been introduced from the raw materials (the level of APCs in raw crab and soy sauce mixed with other ingredients was 3.8 log CFU g-1 and 4.0 log CFU mL-1 respectively); (2) marination of crab in soy sauce may allow cross-contamination by coliforms; (3) only Bacillus cereus and Staphylococcus aureus were qualitatively detected in samples at different stages of manufacture (detection rate of 28 and 5.6% respectively), and these bacteria may impact the microbiological quality and safety of crab marinated in soy sauce; and (4) bacterial counts were either maintained or increased during the manufacturing process (suggesting that no particular step can be targeted to reduce bacterial counts). CONCLUSION: Proper management of raw materials and the marination process are effective critical control points, and alternative interventions may be needed to control bacterial quantity. The results provide important basic information about the production of crab marinated in soy sauce and may facilitate effective implementation of sanitary management practices in related industries and research fields. © 2016 Society of Chemical Industry.
Assuntos
Bacillus cereus/isolamento & purificação , Braquiúros/microbiologia , Frutos do Mar/microbiologia , Alimentos de Soja/análise , Staphylococcus aureus/isolamento & purificação , Animais , Bacillus cereus/genética , Bacillus cereus/crescimento & desenvolvimento , Braquiúros/química , Contaminação de Alimentos/análise , Manipulação de Alimentos , Frutos do Mar/análise , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Estimating the actual occurrence of foodborne illness is challenging because only a small proportion of foodborne illnesses are confirmed and reported. Many studies have attempted to accurately estimate the overall number of cases of foodborne illness, but none have attempted to estimate the burden of foodborne disease in South Korea. This study used data from the Health Insurance Review and Assessment Service (HIRA), a public health surveillance system in South Korea, to calculate the number of cases and hospitalizations due to 18 specific pathogens and unspecified agents commonly transmitted through contaminated food between 2008 and 2012 in South Korea while accounting for uncertainty in the estimate. The estimated annual occurrences of foodborne illness were 336,138 (90% credible interval [CrI]: 258,379-430,740), with inpatient stays (hospitalizations), outpatient visits (foodborne disease infections), and patients' experiences (without visiting physicians) accounting for 2.3% (n=7809 [90% CrI: 7016-8616]), 14.4% (n=48,267 [90% CrI: 45,883-50,695]) and 83.3% (n=280,062 [90% CrI: 201,795-374,091]), respectively. Escherichia coli, including enterohemorrhagic E. coli, caused most illnesses, followed by nontyphoidal Salmonella spp., Staphylococcus aureus, hepatitis A virus, and norovirus. These results will be useful to food safety policymakers for the prevention and control of foodborne pathogens in South Korea.
Assuntos
Escherichia coli Êntero-Hemorrágica/patogenicidade , Contaminação de Alimentos/prevenção & controle , Doenças Transmitidas por Alimentos/epidemiologia , Efeitos Psicossociais da Doença , Inocuidade dos Alimentos , Vírus da Hepatite A/patogenicidade , Hospitalização , Humanos , Norovirus/patogenicidade , Pacientes Ambulatoriais , República da Coreia/epidemiologia , Salmonella/patogenicidade , Staphylococcus aureus/patogenicidadeRESUMO
Prevalence of asymptomatic norovirus infection was investigated in food handlers in South Korea. Among 6,441 subjects, 66 (1.02%) had norovirus infections confirmed by reverse transcription (RT)-PCR (real time and nested). GII-12 and GII-4 were the prevalent genotypes. Our data suggest that infection of asymptomatic food handlers is an important transmission source in norovirus outbreaks.
Assuntos
Infecções por Caliciviridae/epidemiologia , Manipulação de Alimentos , Norovirus/genética , Infecções por Caliciviridae/transmissão , Proteínas do Capsídeo/genética , Surtos de Doenças , Genótipo , Humanos , Dados de Sequência Molecular , Norovirus/classificação , Filogenia , Prevalência , República da Coreia/epidemiologia , Estações do AnoRESUMO
We investigated the clinical characteristics, neuroimaging findings, and final diagnosis of patients with acute isolated or prominent dysarthria who visited the emergency department (ED) between 1 January 2020 and 31 December 2021. Of 2028 patients aged ≥ 18 years with neurologic symptoms treated by a neuro-emergency expert, 75 with acute isolated or predominant dysarthria within 1 week were enrolled. Patients were categorized as having isolated dysarthria (n = 28, 37.3%) and prominent dysarthria (n = 47, 62.7%). The causes of stroke were acute ischemic stroke (AIS) (n = 37, 49.3%), transient ischemic attack (TIA) (n = 14, 18.7%), intracerebral hemorrhage (n = 1, 1.3%), and non-stroke causes (n = 23, 30.7%). The most common additional symptoms were gait disturbance or imbalance (n = 8, 15.4%) and dizziness (n = 3, 13.0%) in the stroke and non-stroke groups, respectively. The isolated dysarthria group had a higher rate of TIA (n = 7, 38.9%), single and small lesions (n = 10, 83.3%), and small-vessel occlusion in Trial of Org 101072 in acute stroke treatment (n = 8, 66.7%). Acute isolated or prominent dysarthria in the ED mostly presented as clinical symptoms of AIS, but other non-stroke and medical causes were not uncommon. In acute dysarthria with ischemic stroke, multiple territorial and small and single lesions are considered a cause.
RESUMO
Acupuncture has been widely used as a therapeutic intervention, and the brain network plays a crucial role in its neural mechanism. This study aimed to investigate the acupuncture mechanism from peripheral to central by identifying how the peripheral molecular signals induced by acupuncture affect the brain neural responses and its functional connectivity. We confirmed that peripheral ERK activation by acupuncture plays a role in initiating acupuncture-induced peripheral proteomic changes in mice. The brain neural activities in the neocortex, hippocampus, thalamus, hypothalamus, periaqueductal grey, and nucleus of the solitary tract (Sol) were significantly changed after acupuncture, and these were altered by peripheral MEK/MAPK inhibition. The arcuate nucleus and lateral hypothalamus were the most affected by acupuncture and peripheral MEK/MAPK inhibition. The hypothalamic area was the most contributing brain region in contrast task PLS analysis. Acupuncture provoked extensive changes in brain functional connectivity, and the posterior hypothalamus showed the highest betweenness centrality after acupuncture. After brain hub identification, the Sol and cingulate cortex were selected as hub regions that reflect both degree and betweenness centrality after acupuncture. These results suggest that acupuncture activates brain functional connectivity and that peripheral ERK induced by acupuncture plays a role in initiating brain neural activation and its functional connectivity.
Assuntos
Terapia por Acupuntura/efeitos adversos , Encéfalo/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteômica , Animais , Encéfalo/diagnóstico por imagem , Hipocampo/metabolismo , Humanos , Hipotálamo/metabolismo , Imageamento por Ressonância Magnética , Camundongos , Neocórtex/metabolismo , Substância Cinzenta Periaquedutal/metabolismo , Núcleo Solitário/metabolismo , Tálamo/metabolismoRESUMO
In this study, a simplified method for the extraction and determination of seven fluoroquinolone residues (danofloxacin, difloxacin, enrofloxacin, marbofloxacin, orbifloxacin, ofloxacin, and sarafloxacin) and three quinolones (oxolinic acid, flumequine, and nalidixic acid), in porcine muscle, table eggs, and commercial whole milk, which required no cleanup step, was devised. This procedure involves the extraction of analytes from the samples via liquid-phase extraction, and the subsequent quantitative determination was accomplished via LC-fluorescence detection. Analyte separation was successfully conducted on an XBridge-C(18) column, with a linear gradient mobile phase composed of acetonitrile and 0.01 M oxalic acid buffer at pH=3.5. The one-step liquid-liquid extraction method evidenced good selectivity, precision (RSDs=0.26-15.07%), and recovery of the extractable analytes, ranging from 61.12 to 115.93% in matrices. The LOQs ranged from 0.3 to 25 microg/kg. A survey of ten samples purchased from local markets was conducted, and none of the samples harbored fluoroquinolone residues. This method is an improvement over existing methodologies, since no additional cleanup was necessary.
Assuntos
Resíduos de Drogas/análise , Ovos/análise , Leite/química , Músculo Esquelético/química , Quinolonas/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Medições Luminescentes , Reprodutibilidade dos Testes , SuínosRESUMO
Because conventional methods for detecting emetic-toxin-producing B. cereus are laborious and costly, various PCR assays, which are easy and cheap, have recently been reported. Therefore, this study estimated and compared the ability of various PCR assays to detect emetic-toxin-producing B. cereus strains isolated in Korea. The PCR assays were performed on 160 B. cereus strains, including 40 emetic-toxin-producing strains. Although the species-specific PCR assays were all shown to be highly specific, the sensitivities varied greatly. The accuracies of the primers were 97.5% (CER), 95.6% (EM1), 96.3% (RE234), 89.4% (CES), and 83.1% (Ces3R/CESR2). Moreover, the CER primer had a higher sensitivity (100%) than all the other primers tested, and a specificity of 96.7%. Thus, the CER primer was shown to be the most effective for screening the emetic-toxin-producing B. cereus strains tested in this study. However, the ability of these PCR assays to identify emetic-toxin-producing B. cereus should also be confirmed using other methods.
Assuntos
Bacillus cereus/metabolismo , Toxinas Bacterianas/biossíntese , Depsipeptídeos/biossíntese , Microbiologia de Alimentos , Reação em Cadeia da Polimerase/métodos , Bacillus cereus/genética , Toxinas Bacterianas/genética , Primers do DNA , DNA Bacteriano/química , DNA Bacteriano/genética , Depsipeptídeos/genética , Coreia (Geográfico) , Sensibilidade e EspecificidadeRESUMO
The current study was undertaken to validate the performance for the determination of both TBA and beta-trenbolone (beta-TB) residues in porcine muscle at concentrations required to monitor compliance with the maximum residue limit (MRL). The method involves a one phase liquid-liquid extraction, cleanup with low-temperature fat precipitation, separation of the respective compounds by HPLC on a Capcell pak C(18) column, use of a methanol-water isocratic system as an eluent, and measurement by UV absorbance detection at 340 nm. Both compounds were confirmed using LC-MS/MS with electrospray interface (ESI) and a triple quadrupole (QqQ) analyzer. The method was found to be precise and accurate, with a linearity range of 1-10 microg/kg (r(2) >0.973). The intra- and interday precision showed good reproducibility with RSDs < or =13.25%. The LODs were 0.12 and 0.22 microg/kg, and the LOQs were 0.37 and 0.66 microg/kg, for TBA and beta-TB, respectively. The applicability of the method was demonstrated by analyzing real samples collected from major cities in the Republic of Korea. No residues of the selected compounds were detected in any of the samples. The advantages of our method are that it is: selective, sensitive, requires a short time for analysis (13 min), and performs simple sample extraction and clean-up procedure with low-temperature fat precipitation as compared to the previously published methods.
Assuntos
Anabolizantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Músculo Esquelético/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta/métodos , Espectrometria de Massas em Tandem/métodos , Acetato de Trembolona/análogos & derivados , Animais , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos , Acetato de Trembolona/análiseRESUMO
Every acupoint has specific indications for acupuncture treatment. These indications, primarily established based on the meridian system, have spatial patterns of symptoms on the human body. We investigated the associations between acupoints and symptom locations in 75 patients with chronic pain who were asked to sketch the localization of their symptoms on body schemes using the bodily sensation map (BSM) system. Combining the BSM and clinical information, we estimated the statistical parameters of relationships between acupoints and spatial information on symptoms. We further visualized spatial patterns of indications of the representative acupoints on the human body template using a Z score. Using a statistical parametric map method, we observed significant activation patterns of 12 acupoint indications with spatial patterns. The 1st group of patterns was distant from the acupoint locus and was strongly associated with the route of the corresponding meridian. The 2nd group was found around the acupoint locus, the majority of which was located at the trunk or back areas. Intensive investigations of the spatial patterns of acupoint indications would be a novel paradigm to explain point specificity of acupuncture treatment based on the original concept of the meridian system. Future studies should include more meaningful clinical data with larger sample sizes.
Assuntos
Pontos de Acupuntura , Dor Crônica/terapia , Dor Crônica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise EspacialRESUMO
The present study examined 469 commercially available fermented alcoholic beverages (FABs), including beer (draft, microbrewed, and pasteurized), fruit wine (grape and others), refined rice wine, and yakju (raw and pasteurized). Samples were screened for Escherichia coli and eight foodborne pathogens (Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Yersinia enterocolitica), and the aerobic plate count, lactic acid bacteria, acetic acid bacteria, fungi, and total coliforms were also enumerated. Microbrewed beer contained the highest number of microorganisms (average aerobic plate count, 3.5; lactic acid bacteria, 2.1; acetic acid bacteria, 2.0; and fungi, 3.6 log CFU/ml), followed by draft beer and yakju (P < 0.05), whereas the other FABs contained , 25 CFU/25 ml microorganisms. Unexpectedly, neither microbial diversity nor microbial count correlated with the alcohol content (4.7 to 14.1%) or pH (3.4 to 4.2) of the product. Despite the harsh conditions, coliforms (detected in 23.8% of microbrewed beer samples) and B. cereus (detected in all FABs) were present in some products. B. cereus was detected most frequently in microbrewed beer (54.8% of samples) and nonpasteurized yakju (50.0%), followed by pasteurized yakju (28.8%), refined rice wine (25.0%), other fruit wines (12.3%), grape wine (8.6%), draft beer (5.6%), and pasteurized beer (2.2%) (P < 0.05). The finding that spore-forming B. cereus and coliform bacteria can survive the harsh conditions present in alcoholic beverages should be taken into account (alongside traditional quality indicators such as the presence of lactic acid-producing bacteria, acetic acid-producing bacteria, or both) when developing manufacturing systems and methods to prolong the shelf life of high-quality FAB products. New strategic quality management plans for various FABs are needed.
Assuntos
Bebidas Alcoólicas/microbiologia , Cerveja/microbiologia , Fermentação , Vinho/microbiologia , Bacillus cereus/isolamento & purificação , Bactérias/isolamento & purificação , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Frutas , Fungos , Oryza , VitisRESUMO
Many strains of Bacillus cereus cause gastrointestinal diseases, and the closely related insect pathogen Bacillus thuringiensis has also been involved in outbreaks of diarrhea. The diarrheal diseases are attributed to enterotoxins. Sixteen reference strains of B. cereus and nine commercial and 12 reference strains of B. thuringiensis were screened by PCR for the presence of 10 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, bceT, entFM, and entS), one emetogenic gene (ces), seven hemolytic genes (hlyA, hlyII, hlyIII, plcA, cerA, cerB, and cerO), and a pleiotropic transcriptional activator gene (plcR). These genes encode various enterotoxins and other virulence factors thought to play a role in infections of mammals. Amplicons were successfully generated from the strains of B. cereus and B. thuringiensis for each of these sequences, except the ces gene. Intriguingly, the majority of these B. cereus enterotoxin genes and other virulence factor genes appeared to be widespread among B. thuringiensis strains as well as B. cereus strains.
Assuntos
Bacillus cereus/genética , Bacillus thuringiensis/genética , Enterotoxinas/genética , Genes Bacterianos , Fatores de Virulência/genética , Testes Genéticos , Reação em Cadeia da PolimeraseRESUMO
Ready-to-eat (RTE) Jokbal (Pig's trotter), which consists of pig's feet cooked in soy sauce and various spices, is a very popular and widely sold in Korean retail markets. Commercially, the anaerobically packed Jokbal have also become a popular RTE food in several convenience stores. This study evaluates the effects of storage temperature and packaging methods for the growth of C. perfringens in Jokbal. Growth kinetic parameters of C. perfringens in aerobically and anaerobically packed Jokbals are determined at each temperature by the modified Gompertz equation. The lag time, specific growth rate, and maximum population density of C. perfringens are being analyzed as a function of temperature and packaging method. The minimum growth temperature of C. perfringens in aerobically and anaerobically packed Jokbal is 24â and 18â, respectively. The C. perfringens in Jokbal did not grow under conditions of over 50â regardless of the packaging methods, indicating that the holding temperature of Jokbal in markets must be maintained at above 50â or below 18â. Growth of C. perfringens in anaerobically packed Jokbal is faster than in aerobically packed Jokbal when stored under the same conditions. This indicates that there are a higher risks associated with C. perfringens for anaerobically packed meat products.
RESUMO
The decontamination efficacy of neutral electrolyzed water (NEW) was evaluated using shredded cabbages and carrots in both a scalable laboratory system (experiment I) and an actual processing line in a plant (experiment II). In experiment I, the antimicrobial effect of highly concentrated NEW (up to the maximum regulated level: 200ppm) was tested to determine the appropriate conditions for use in an actual plant test: (1) hypochlorous acid (HClO) concentration (100, 150, and 200ppm), (2) ratio of sample weight to NEW volume (1:5, 1:10, and 1:20), and (3) treatment time (5, 10, 20, and 30min), using 2kg of shredded cabbages and carrots. In experiment II, the feasibility of the NEW treatment was validated on an actual processing line (treatment unit: 20kg), including cutting, three washing steps (two air bubble washes for 5min each and 150ppm NEW for 5min at ratio of 1:10), rinsing (5min), and dehydration (5min). Overall, the microbial reductions tended to increase as the HClO concentration, ratio of sample to NEW, and treatment time increased. The results obtained from experiment I indicated that the maximum conditions (NEW 200ppm, 1:20, 30min) achieved 3.3-3.5 log CFU/g reductions in the coliform counts. After treatment with 200ppm NEW for >10min, however, there were noticeable color changes (color differences, DE>5.0) in both the shredded cabbages and carrots. In the experiment II, the microbial populations were not affected by cutting and two air bubble treatments, whereas washing with NEW greatly reduced both the aerobic plate counts (1.93-2.17 log CFU/g) and coliform counts (0.97-1.51 log CFU/g). More than 2 log CFU/g of indigenous flora were reduced from raw materials to final products with both shredded cabbages (2.05-2.48 log CFU/g) and carrots (2.34-2.76 log CFU/g). These results may provide useful recommendations for the practical application of highly concentrated NEW in the fresh-cut produce industry to improve the microbiological safety without quality deterioration.
RESUMO
Microbiological quality of laver, one of the edible seaweeds, has not been reported in a real processing line. Laver or supplements were collected from six manufacturers (A to F) to assess potential microbiological hazards and the critical control points in commercial processing lines. Aerobic plate counts (APC), coliform counts, Bacillus cereus, Staphylococcus aureus, and Vibrio parahaemolyticus were enumerated, and the presence of B. cereus, Listeria monocytogenes, Salmonella, S. aureus, and V. parahaemolyticus were confirmed during processing. The raw material, i.e., dried laver, had a high initial APC level (4.4 to 7.8 log CFU/g), which decreased gradually during processing (final products, 1.3 to 5.9 log CFU/g). Coliforms and B. cereus were not detected in any of the final products, but they were present in some raw materials and semiprocessed products in quantitative analysis. After enrichment for recovery of stress-injured cells, E. coli and foodborne pathogens were not detected in any samples, with the exception of B. cereus. Heat-injured and spore-forming B. cereus isolates were occasionally obtained from some of the raw materials and products after enrichment, thus B. cereus may be a potential microbiological hazard that should be controlled using strategic intervention measures. Secondary roasting (260 to 400°C, 2 to 10 s) significantly reduced the APC (maximum log reduction, 4.7 log CFU/g), and this could be a key intervention step for controlling microbiological hazards during processing (critical control point). When this step was performed appropriately, according to the processing guide for each plant, the microorganisms were inactivated more successfully in the products. This study provides scientific evidence that may facilitate the development of strategies for microbiological hazard control and hygienic management guidelines for real manufacturing plants.
Assuntos
Manipulação de Alimentos/normas , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/prevenção & controle , Alga Marinha/microbiologia , Bacillus cereus/isolamento & purificação , Contagem de Colônia Microbiana , Manipulação de Alimentos/métodos , Alimentos em Conserva/microbiologia , Doenças Transmitidas por Alimentos/microbiologia , Temperatura Alta , Listeria monocytogenes/isolamento & purificação , Gestão da Segurança , Salmonella/isolamento & purificação , Estações do Ano , Staphylococcus aureus/isolamento & purificação , Vibrio parahaemolyticus/isolamento & purificaçãoRESUMO
The facial feedback hypothesis suggests that feedback from cutaneous and muscular afferents influences our emotions during the control of facial expressions. Enhancing facial expressiveness produces an increase in autonomic arousal and self-reported emotional experience, whereas limiting facial expression attenuates these responses. The present study investigated differences in autonomic responses during imitated versus observed facial expressions. Thus, we obtained the facial electromyogram (EMG) of the corrugator muscle, and measured the skin conductance response (SCR) and pupil size (PS) of participants while they were either imitating or simply observing emotional expressions of anger. We found that participants produced significantly greater responses across all three measures (EMG, SCR, and PS) during active imitation than during passive observation. These results show that amplified feedback from facial muscles during imitation strengthens sympathetic activation in response to negative emotional cues. Our findings suggest that manipulations of muscular feedback could be used to modulate the bodily expression of emotion, including autonomic responses to the emotional cues.
Assuntos
Sinais (Psicologia) , Emoções/fisiologia , Músculos Faciais/fisiologia , Pele/inervação , Sistema Nervoso Simpático/fisiologia , Adolescente , Adulto , Eletromiografia , Face , Expressão Facial , Retroalimentação , Feminino , Resposta Galvânica da Pele , Humanos , Masculino , Músculo Esquelético/inervação , Adulto JovemRESUMO
Background. The rubber hand illusion (RHI) is an experimental paradigm that manipulates important aspects of body self-awareness. Objectives. We were interested in whether modifying bodily self-awareness by manipulation of body ownership and visual expectations using the RHI would change the subjective perception of pain as well as the autonomic response to acupuncture needle stimulation. Methods. Acupuncture needle stimulation was applied to the real hand during the RHI with (experiment 1) or without (experiment 2) visual expectation while measuring concurrent autonomic changes such as the skin conductance response (SCR). Subjective responses such as perception of the RHI and perceived pain were measured by questionnaires. Results. In experiment 1, the amplitude of the increase in SCR was visibly higher during the synchronous session compared with that of the asynchronous session. In experiment 2, the amplitude of the increase of SCR was lower for the synchronous session compared with that for the asynchronous session. Comparing these two experiments, the visual expectation of needle stimulation produced a greater autonomic response to acupuncture stimulation. Conclusions. Our findings suggest that the sympathetic response to acupuncture needle stimulation is primarily influenced by visual expectation rather than by modifications of body ownership.