scholarly journals Virulence Characterization of Listeria monocytogenes, Listeria innocua, and Listeria welshimeri Isolated from Fish and Shrimp Using In Vivo Early Zebrafish Larvae Models and Molecular Study

Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1028
Author(s):  
Arkadiusz Józef Zakrzewski ◽  
Wioleta Chajęcka-Wierzchowska ◽  
Anna Zadernowska ◽  
Piotr Podlasz
Keyword(s):  
Virulence Genes ◽  
Molecular Study ◽  
Larval Survival ◽  
Listeria Innocua ◽  
Foodborne Diseases ◽  
Zebrafish Larvae ◽  
Potential Impact ◽  
Listeria Welshimeri

Listeriosis is one of the most notable foodborne diseases and is characterized by high rates of mortality. L. monocytogenes is the main cause of human listeriosis outbreaks, however, there are isolated cases of disease caused by other species of the genus Listeria. The aim of this study was to evaluate strains of L. monocytogenes (n = 7), L. innocua (n = 6), and L. welshimeri (n = 2) isolated from fish and shrimps for their virulence based on the presence of virulence genes and the in vivo Danio rerio (zebrafish) larvae models. A total of 15 strains were analyzed. The zebrafish larvae model showed that the larvae injected with L. monocytogenes strains were characterized by the lowest survival rate (46.5%), followed by L. innocua strains (64.2%) and L. welshimeri (83.0%) strains. Multiplex PCRs were used for detection of selected virulence genes (luxS, actA2, prfA, inlB, rrn, iap, sigB, plcB, actA, hlyA), the majority of which were present in L. monocytogenes. Only a few virulence-related genes were found in L. welshimeri, however, no correlation between the occurrence of these genes and larval survival was confirmed. This research highlights the importance of the potential impact that Listeria spp. strains isolated from fish and shrimps may have on consumers.

scholarly journals Polystyrene nanoplastics accumulate in ZFL cell lysosomes and in zebrafish larvae after acute exposure, inducing a synergistic immune response in vitro without affecting larval survival in vivo

2020 ◽  
Vol 7 (8) ◽  
pp. 2410-2422
Author(s):  
Irene Brandts ◽  
Marlid Garcia-Ordoñez ◽  
Lluis Tort ◽  
Mariana Teles ◽  
Nerea Roher
Keyword(s):  
Immune Response ◽  
Larval Survival ◽  
Liver Cells ◽  
Acute Exposure ◽  
Zebrafish Larvae ◽  
Lethal Infection ◽  
Zebrafish Liver ◽  
Immune Response In Vitro

Polystyrene nanoplastics are internalized in zebrafish liver cells, accumulating in lysosomes, and in zebrafish larvae but do not affect the larval suvival to a lethal infection.

scholarly journals Molecular characterization of virulence factors in Aeromonas hydrophila obtained from fish

2012 ◽  
Vol 32 (8) ◽  
pp. 701-706 ◽  
Author(s):  
Samira T.L. Oliveira ◽  
Gisele Veneroni-Gouveia ◽  
Mateus M. Costa
Keyword(s):  
Virulence Factors ◽  
Aeromonas Hydrophila ◽  
Nile Tilapia ◽  
Virulence Genes ◽  
Saline Solution ◽  
Specific Primers ◽  
In Vivo Tests ◽  
Polymerase Chain

Multiple factors can be involved in the virulence processes of Aeromonas hydrophila. The objective of the present paper was to verify the presence of aerolysin, hidrolipase, elastase and lipase virulence genes through the polymerase chain reaction (PCR) in A. hydrophila isolates obtained from fish of the São Francisco River Valley, and to evaluate virulence according to the presence of these genes in Nile tilapia fingerlings. One hundred and fourteen isolates from the bacteria were used. DNA was heat extracted and PCR undertaken using specific primers described in the literature. For in vivo tests Nile tilapia fingerlings were used. From the PCR tests, negative isolates for all genes tested were selected, positive isolates for two genes (aerolysin and elastase) and positive for the four genes tested. These were inoculated at a concentration of 10(8) UFC/ml into the tilapias, considered as treatments; another group of animals was used as control (with inoculation of saline solution). In all, 12 distinct standards regarding the presence of virulence factors in isolates from A. hydrophila, were observed. Of the 114 isolates analyzed, 100 (87.72%) presented at least one of the virulence factors under study. The virulence factors were widely distributed among the A. hydrophila isolates. Aerolysin was the most frequent virulence factor present in the isolates analyzed. A. hydrophila led to the mortality of the Nile tilapia fingerlings, regardless of the absence or quantity of virulence genes tested.

scholarly journals Detection of virulence-associated genes in Salmonella Enteritidis isolates from chicken in South of Brazil

2013 ◽  
Vol 33 (12) ◽  
pp. 1416-1422 ◽  
Author(s):  
Karen A. Borges ◽  
Thales Q. Furian ◽  
Anderlise Borsoi ◽  
Hamilton L.S. Moraes ◽  
Carlos T.P. Salle ◽  
...  
Keyword(s):  
Salmonella Enteritidis ◽  
Virulence Genes ◽  
In Vivo Studies ◽  
Salmonella Spp ◽  
Complex Processes ◽  
South Of Brazil ◽  
Different Strains ◽  
Genetic Profiles

Salmonella spp. are considered the main agents of foodborne disease and Salmonella Enteritidis is one of the most frequently isolated serovars worldwide. The virulence of Salmonella spp. and their interaction with the host are complex processes involving virulence factors to overcome host defenses. The purpose of this study was to detect virulence genes in S. Enteritidis isolates from poultry in the South of Brazil. PCR-based assays were developed in order to detect nine genes (lpfA, agfA, sefA, invA, hilA, avrA, sopE, sivH and spvC) associated with the virulence in eighty-four isolates of S. Enteritidis isolated from poultry. The invA, hilA, sivH, sefA and avrA genes were present in 100% of the isolates; lpfA and sopE were present in 99%; agfA was present in 96%; and the spvC gene was present in 92%. It was possible to characterize the isolates with four different genetic profiles (P1, P2, P3 and P4), as it follows: P1, positive for all genes; P2, negative only for spvC; P3, negative for agfA; and P4, negative for lpfA, spvC and sopE. The most prevalent profile was P1, which was present in 88% of the isolates. Although all isolates belong to the same serovar, it was possible to observe variations in the presence of these virulence-associated genes between different isolates. The characterization of the mechanisms of virulence circulating in the population of Salmonella Enteritidis is important for a better understanding of its biology and pathogenicity. The frequency of these genes and the establishment of genetic profiles can be used to determine patterns of virulence. These patterns, associated with in vivo studies, may help develop tools to predict the ability of virulence of different strains.

scholarly journals Phenotypic and molecular characterization of Salmonella enterica serovar Sofia, an avirulent species in Australian poultry

Microbiology ◽  
2011 ◽  
Vol 157 (4) ◽  
pp. 1056-1065 ◽  
Author(s):  
Emily Gan ◽  
Fiona J. Baird ◽  
Peter J. Coloe ◽  
Peter M. Smooker
Keyword(s):  
Salmonella Enterica ◽  
Virulence Genes ◽  
Meat Products ◽  
Virulence Gene ◽  
Cleavage Sites ◽  
Pathogenic Potential ◽  
Serovar Typhimurium ◽  
Restriction Cleavage

Salmonella enterica serovar Sofia (S. Sofia) is often isolated from chickens in Australia. However, despite its high frequency of isolation from chicken and chicken meat products, S. Sofia is rarely associated with animal or human salmonellosis, presumably because this serovar is avirulent in nature. The objective of this work was to investigate the phenotypic and molecular properties of S. Sofia in order to assess its pathogenic potential. Our in vivo studies support the observation that this serovar can colonize tissues, but does not cause disease in chickens. This was further confirmed with tissue culture assays, which showed that the ability of S. Sofia to adhere, invade and survive intracellularly is significantly diminished compared with the pathogenic Salmonella enterica serovar Typhimurium (S. Typhimurium) 82/6915. Molecular analysis of Salmonella pathogenicity islands (SPIs) showed that most of the differences observed in SPI1 to SPI5 of S. Sofia could be attributed to minor changes in the sequences, as indicated by a loss or gain of restriction cleavage sites within these regions. Sequence analysis demonstrated that the majority of virulence genes identified were predicted to encode proteins sharing a high identity (75–100 %) with corresponding proteins from S. Typhimurium. However, a number of virulence genes in S. Sofia have accumulated mutations predicted to affect transcription and/or translation. The avirulence of this serovar is probably not the result of a single genetic change but rather of a series of alterations in a large number of virulence-associated genes. The acquisition of any single virulence gene will almost certainly not be sufficient to restore S. Sofia virulence.

scholarly journals Atypical HemolyticListeria innocuaIsolates Are Virulent, albeit Less thanListeria monocytogenes

2019 ◽  
Vol 87 (4) ◽  
Author(s):  
Alexandra Moura ◽  
Olivier Disson ◽  
Morgane Lavina ◽  
Pierre Thouvenot ◽  
Lei Huang ◽  
...  
Keyword(s):  
Human Exposure ◽  
Functional Characterization ◽  
Listeria Innocua ◽  
Whole Genome ◽  
Gene Products ◽  
Content Type ◽  
Functional Assays

ABSTRACTListeria innocuais considered a nonpathogenicListeriaspecies. Natural atypical hemolyticL. innocuaisolates have been reported but have not been characterized in detail. Here, we report the genomic and functional characterization of representative isolates from the two known natural hemolyticL. innocuaclades. Whole-genome sequencing confirmed the presence ofListeriapathogenicity islands (LIPI) characteristic ofListeria monocytogenesspecies. Functional assays showed that LIPI-1 andinlAgenes are transcribed, and the corresponding gene products are expressed and functional. Usingin vitroandin vivoassays, we show that atypical hemolyticL. innocuais virulent, can actively cross the intestinal epithelium, and spreads systemically to the liver and spleen, albeit to a lesser degree than the referenceL. monocytogenesEGDe strain. Although human exposure to hemolyticL. innocuais likely rare, these findings are important for food safety and public health. The presence of virulence traits in someL. innocuaclades supports the existence of a common virulent ancestor ofL. monocytogenesandL. innocua.

Functional characterization of human brown adipose tissue metabolism

2020 ◽  
Vol 477 (7) ◽  
pp. 1261-1286 ◽  
Author(s):  
Marie Anne Richard ◽  
Hannah Pallubinsky ◽  
Denis P. Blondin
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Functional Characterization ◽  
Human Infants ◽  
Positron Emission ◽  
Brown Adipose ◽  
Treatment Of Obesity ◽  
And Function

Brown adipose tissue (BAT) has long been described according to its histological features as a multilocular, lipid-containing tissue, light brown in color, that is also responsive to the cold and found especially in hibernating mammals and human infants. Its presence in both hibernators and human infants, combined with its function as a heat-generating organ, raised many questions about its role in humans. Early characterizations of the tissue in humans focused on its progressive atrophy with age and its apparent importance for cold-exposed workers. However, the use of positron emission tomography (PET) with the glucose tracer [18F]fluorodeoxyglucose ([18F]FDG) made it possible to begin characterizing the possible function of BAT in adult humans, and whether it could play a role in the prevention or treatment of obesity and type 2 diabetes (T2D). This review focuses on the in vivo functional characterization of human BAT, the methodological approaches applied to examine these features and addresses critical gaps that remain in moving the field forward. Specifically, we describe the anatomical and biomolecular features of human BAT, the modalities and applications of non-invasive tools such as PET and magnetic resonance imaging coupled with spectroscopy (MRI/MRS) to study BAT morphology and function in vivo, and finally describe the functional characteristics of human BAT that have only been possible through the development and application of such tools.

Comparison of Immunological and Functional Assays for Measurement of Soluble Fibrin

1995 ◽  
Vol 74 (02) ◽  
pp. 673-679 ◽  
Author(s):  
C E Dempfle ◽  
S A Pfitzner ◽  
M Dollman ◽  
K Huck ◽  
G Stehle ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Low Grade ◽  
Plasma Samples ◽  
Normal Range ◽  
Soluble Fibrin ◽  
Discriminating Power ◽  
Fibrin Monomer ◽  
Cerebral Ischemic

SummaryVarious assays have been developed for quantitation of soluble fibrin or fibrin monomer in clinical plasma samples, since this parameter directly reflects in vivo thrombin action on fibrinogen. Using plasma samples from healthy blood donors, patients with cerebral ischemic insult, patients with septicemia, and patients with venous thrombosis, we compared two immunologic tests using monoclonal antibodies against fibrin-specific neo-epitopes, and two functional tests based on the cofactor activity of soluble fibrin complexes in tPA-induced plasminogen activation. Test A (Enzymun®-Test FM) showed the best discriminating power among normal range and pathological samples. Test B (Fibrinostika® soluble fibrin) clearly separated normal range from pathological samples, but failed to discriminate among samples from patients with low grade coagulation activation in septicemia, and massive activation in venous thrombosis. Functional test C (Fibrin monomer test Behring) displayed good discriminating power between normal and pathological range samples, and correlated with test A (r = 0.61), whereas assay D (Coa-Set® Fibrin monomer) showed little discriminating power at values below 10 μg/ml and little correlation with other assays. Standardization of assays will require further characterization of analytes detected.

Vibrio harveyi virulence gene expression in vitro and in vivo during infection in black tiger shrimp Penaeus monodon

2020 ◽  
Vol 139 ◽  
pp. 153-160
Author(s):  
S Peeralil ◽  
TC Joseph ◽  
V Murugadas ◽  
PG Akhilnath ◽  
VN Sreejith ◽  
...  
Keyword(s):  
Gene Expression ◽  
Virulence Genes ◽  
Vibrio Harveyi ◽  
Penaeus Monodon ◽  
Challenge Test ◽  
Virulence Gene ◽  
Economic Losses ◽  
Virulence Gene Expression

Luminescent Vibrio harveyi is common in sea and estuarine waters. It produces several virulence factors and negatively affects larval penaeid shrimp in hatcheries, resulting in severe economic losses to shrimp aquaculture. Although V. harveyi is an important pathogen of shrimp, its pathogenicity mechanisms have yet to be completely elucidated. In the present study, isolates of V. harveyi were isolated and characterized from diseased Penaeus monodon postlarvae from hatcheries in Kerala, India, from September to December 2016. All 23 tested isolates were positive for lipase, phospholipase, caseinase, gelatinase and chitinase activity, and 3 of the isolates (MFB32, MFB71 and MFB68) showed potential for significant biofilm formation. Based on the presence of virulence genes, the isolates of V. harveyi were grouped into 6 genotypes, predominated by vhpA+ flaB+ ser+ vhh1- luxR+ vopD- vcrD+ vscN-. One isolate from each genotype was randomly selected for in vivo virulence experiments, and the LD50 ranged from 1.7 ± 0.5 × 103 to 4.1 ± 0.1 × 105 CFU ml-1. The expression of genes during the infection in postlarvae was high in 2 of the isolates (MFB12 and MFB32), consistent with the result of the challenge test. However, in MFB19, even though all genes tested were present, their expression level was very low and likely contributed to its lack of virulence. Because of the significant variation in gene expression, the presence of virulence genes alone cannot be used as a marker for pathogenicity of V. harveyi.

Insulinomimetic properties of trace elements and characterization of their in vivo mode of action

Diabetes ◽  
1990 ◽  
Vol 39 (10) ◽  
pp. 1243-1250 ◽  
Author(s):  
L. Rossetti ◽  
A. Giaccari ◽  
E. Klein-Robbenhaar ◽  
L. R. Vogel
Keyword(s):  
Trace Elements ◽  
Mode Of Action
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