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1.
Biomédica (Bogotá) ; 40(4): 722-733, oct.-dic. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1142437

ABSTRACT

Resumen: Introducción. La variante monofásica (1,4,[5],12:i:-) de Salmonella Typhimurium ocupa los primeros lugares en los programas de vigilancia de Salmonella a nivel mundial. En Colombia, Salmonella enterica variante monofásica alcanza el cuarto lugar en cuanto a los aislamientos clínicos recuperados por medio de la vigilancia por laboratorio del Grupo de Microbiología del Instituto Nacional de Salud, pero se desconoce si dichos aislamientos están relacionados con la variante monofásica de Typhimurium que circula a nivel global, y con sus características genéticas y fenotípicas. Objetivo. Caracterizar los aislamientos de Salmonella monofásica recuperados en Colombia entre el 2015 y el 2018 por el Grupo de Microbiología del Instituto Nacional de Salud. Materiales y métodos. Se analizaron 286 aislamientos clínicos de Salmonella enterica variante monofásica mediante PCR o secuenciación del genoma completo (Whole Genome Sequencing, WGS) para confirmar si correspondían a Salmonella Typhimurium variante monofásica, en tanto que, en 54 aislamientos, se determinó la estructura genética del operón que codifica la segunda fase flagelar y, en 23, se evaluó la motilidad, el crecimiento y la expresión de las proteínas de membrana externa. Resultados. El 61 % (n=174) de los aislamientos de Salmonella monofásica correspondió a Salmonella Typhimurium serovar monofásico. El 64,8 % (n=35/54) se relacionó con el clon europeo-español y, el 13 % (n=7/54), con el estadounidense. En dos aislamientos de orina se encontró una diferencia significativa en la motilidad y el crecimiento, así como ausencia de la porina OmpD en medio mínimo M9. Conclusiones. En el periodo de estudio, circuló en Colombia la variante monofásica de Salmonella Typhimurium relacionada con el clon europeo-español, y se registró ausencia total del operón fljAB. Los resultados evidenciaron cambios fenotípicos en los aislamientos provenientes de muestras de orina que sugieren adaptación en procesos invasivos.


Abstract: Introduction. The Salmonella Typhimurium monophasic variant (1,4,[5],12:i:-) is currently the most commonly detected variant in Salmonella surveillance programs worldwide. In Colombia, the Salmonella enterica monophasic variant is the fourth most common clinical isolate recovered through the laboratory surveillance of the Grupo de Microbiología from the Instituto Nacional de Salud; however, it is unknown whether these isolates are closely related to the monophasic Typhimurium variant, which circulates globally, and their genetic and phenotypic characteristics have not been reported. Objective. To characterize monophasic Salmonella enterica isolates identified in Colombia from 2015 to 2018 by the Instituto Nacional de Salud. Materials and methods. Two hundred eighty-six clinical isolates of the monophasic Salmonella enterica variant were analyzed by PCR or whole-genome sequencing to confirm whether they corresponded to the Salmonella Typhimurium monophasic variant while the genetic structure of the operon encoding the second flagellar phase was determined in 54 isolates. Motility, growth, and expression of the outer membrane proteins were evaluated in 23 isolates. Results. During the study period in Colombia, 61% (n=174) of Salmonella monophasic isolates belonged to Salmonella Typhimurium serovar monophasic (1,4,[5],12:i-). Of these, 64.8% (n=35/54) were related to the European/Spanish clone and 13% (n=7/54) to the U.S. clone. Two isolates recovered from urine samples showed differences in motility, growth, and the absence of the OmpD porin in M9 minimal medium. Conclusions. Most of the monophasic Salmonella Typhimurium variants that have circulated in Colombia since 2015 lacked the second phase of operon fljAB, which is related to the European/Spanish clone. The results evidenced phenotypic changes in urine samples suggesting bacterial adaptation in the case of these invasive samples.


Subject(s)
Salmonella typhimurium , Porins , Colombia , Surveillance , Flagella
2.
Rev. chil. nutr ; 47(2): 281-285, abr. 2020. tab
Article in English | LILACS | ID: biblio-1115499

ABSTRACT

Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.


Los conservantes sintéticos están ampliamente presentes en los alimentos procesados, pero la mayoría tienen potencial carcinogénico, lo que requiere el desarrollo de nuevas alternativas naturales para el control microbiano, como los extractos de frutas. El objetivo del estudio fue evaluar la caracterización química, la actividad antioxidante y antimicrobiana de la pulpa de manzana de azúcar (Annona squamosa L.). Se evaluaron las características fisicoquímicas, y se evaluó su actividad antioxidante mediante el método DPPH y antimicrobiano por difusión en disco, concentración inhibitoria mínima y concentración bactericida mínima contra cepas de Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes y Staphylococcus aureus. El análisis fisicoquímico reveló que la pulpa de manzana de azúcar tiene 75.0% de humedad, 3.0% de cenizas, 4.0% de proteínas, 0.2% de lípidos, 3.3% de fibras y 14.5% de carbohidratos. La actividad antioxidante del extracto por el método DPPH fue del 20.6%. El extracto de pulpa de la manzana de azúcar tenía zona de inhibición para Staphylococcus aureus, efecto inhibidor satisfactorio contra Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Salmonella Typhimurium, pero no presenta efecto bactericida. La pulpa de manzana de azúcar presenta niveles adecuados de nutrientes y potencial para la aplicación de alimentos debido a su actividad microbiológica y propiedades antioxidantes.


Subject(s)
Plant Extracts/pharmacology , Annona/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effects , Carbohydrates/analysis , Plant Extracts/chemistry , Proteins/analysis , Microbial Sensitivity Tests , Escherichia coli/drug effects , Lipids/analysis , Listeria monocytogenes/drug effects , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry
3.
Braz. J. Pharm. Sci. (Online) ; 56: e18654, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132041

ABSTRACT

The 4-Hydroxycoumarin derivatives are known to show a broad spectrum of pharmacological applications. In this paper we are reporting the synthesis of a new series of 4-Hydroxycoumarin derivatives synthesized through Knovenegal condensation; they were characterized by using UV-Vis, FT-IR, NMR spectroscopies. The synthesized compounds were evaluated for antibacterial activity against Staphylococcus aureus and Salmonella typhimurium strains. The compounds (2), (3) and (8) showed favorable antibacterial activity with zone of inhibitions 26.5± 0.84, 26.0 ± 0.56 and 26.0 ± 0.26 against Staphylococcus aureus (Gram-positive) respectively. However, the compounds (5) and (9) were found more active with 19.5 ± 0.59 and 19.5 ± 0.32 zone of inhibitions against Salmonella typhimurium (Gram-negative). Whereas, in urease inhibition assay, none of the synthesized derivatives showed significant anti-urease activity; although, in carbonic anhydrase-II inhibition assay, the compound (2) and (6) showed enzyme inhibition activity with IC50 values 263±0.3 and 456±0.1, respectively.


Subject(s)
Carbonic Anhydrases/adverse effects , Inhibitory Concentration 50 , Salmonella typhimurium/classification , Urease/adverse effects , Magnetic Resonance Spectroscopy/methods , Condensation
4.
Braz. J. Pharm. Sci. (Online) ; 56: e18468, 2020. tab
Article in English | LILACS | ID: biblio-1249147

ABSTRACT

Origanum vulgare L. (OVEO) essential oil has been considered a candidate antimicrobial for use in food conservation systems. However, studies on the influence of concomitant variations of different food components or physicochemical parameters on the antibacterial properties of OVEO are scarce. This study assessed the influence of concomitant variations in amounts of proteins - PTN (4.0, 6.0 or 8.0 g/100 mL) and lipids - LIP (3.75, 5.0 or 6.25 g/100 mL) and pH values (5.0, 5.5 or 6.0) in cultivation medium on the inhibitory effects of OVEO against Escherichia coli (EC) and Salmonella Typhimurium (ST). Lowest minimum inhibitory concentration values of OVEO against EC and ST were observed in media with the highest LIP amounts regardless the PTN amount and pH value. In absorbance based microtiter plate assay (MPA), for both EC and ST, OVEO caused the lowest Grmax values in medium containing the highest LIP and PTN amounts and lowest pH value. Highest Grmax values for EC and ST were observed in medium containing the lowest LIP and PTN amount and highest pH value. Grmax values estimated from viable counts of EC and ST in tested media with OVEO confirmed bacterial growth behavior similar to that observed in MPA. Overall, the LIP amount in media was as the most influential factor to enhance the antibacterial effects of OVEO. These results indicate that the concomitant influence of LIP and PTN amounts and pH values on the antibacterial effects of OVEO should be considered for optimizing its antimicrobial efficacy in foods.


Subject(s)
Salmonella typhimurium/classification , Oils, Volatile/analysis , Origanum/classification , Escherichia coli/classification , Lipids/adverse effects , Proteins , Microbial Sensitivity Tests/instrumentation , Bacterial Growth , Efficacy , Food , Hydrogen-Ion Concentration
5.
Vaccimonitor (La Habana, Print) ; 28(1)ene.-abr. 2019. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1094616

ABSTRACT

Con la finalidad de evaluar la patogenia en cepas de Salmonella Typhimurium con mutaciones en los genes invG/invE de la Isla de Patogenicidad de Salmonella 1 (SPI-1) y de los genes ssaJ/ssaK en la SPI-2, se evaluaron los modelos asa intestinal ligada de ratón asociado a la observación de los tejidos por microscopía electrónica de transmisión (MET) y la producción de salmonelosis sistémica en ratón. Para ello, se utilizaron seis cepas de Salmonella: S. Typhimurium SL-1344 (cepa control) y sus derivadas mutantes: ∆invEG S. Typhimurium SL-1344 (mutante en SPI-1) y ∆ssaJK S. Typhimurium SL-1344 (mutante en SPI-2), S. Typhimurium (cepa clínica) y sus derivadas mutantes: ∆invEG S. Typhimurium y ∆ssaJK S. Typhimurium. Los resultados de MET permitieron verificar las alteraciones morfológicas del epitelio intestinal en el ratón infectado con cepas de Salmonella cuyos genes de patogenicidad estaban intactos. Fue comprobada la pérdida del poder invasivo solo en las cepas mutadas en la SPI-1. A través del modelo de salmonelosis sistémica en ratón se pudo comprobar la pérdida de la capacidad de diseminación en ambas mutantes. En conclusión los modelos permitieron verificar la importancia que tienen los genes invG/invE de la SPI-1 y ssaJ/ssaK de la SPI-2 en la patogenia de la salmonelosis, utilizando como modelo experimental de infección ratones BALB/c. Se sugieren estos modelos in vivo para evaluar mutantes de genes implicados en la patogenia de Salmonella, ya que representan una herramienta importante para la comprensión de la interacción Salmonella-hospedero(AU)


With the aim of evaluate the pathogenesis in Salmonella Typhimurium strains with mutations in genes invG/invE of Salmonella Pathogenicity Island 1 (SPI-1) and genes ssaJ/ssaK in the SPI-2 models were evaluated ligated intestinal loop associated mouse tissues by observation by transmission electron microscopy (TEM) and the production of mouse systemic salmonellosis. For this, we used six Salmonella strains: S. Typhimurium SL-1344 (control strain) and its derived mutants: ΔinvEG S. Typhimurium SL-1344 (mutant in SPI-1) and ΔssaJK S. Typhimurium SL-1344 (mutant in SPI-2), S. Typhimurium (clinical isolate) and its derived mutants: ΔinvEG S.Typhimurium and ΔssaJK S. Typhimurium. TEM results allowed us to verify the morphological alterations of the intestinal epithelium in mice infected with Salmonella strains whose pathogenicity genes were intact. It was proven invasive power loss only in strains mutated in the SPI-1. Through systemic salmonellosis model mouse we noted the loss of the ability to spread in both mutants. In conclusion, the models allowed us to verify the importance of the invG/invE genes of SPI-1 and ssaJ/ssaK of SPI-2 in the pathogenesis of salmonellosis, using BALB/c mice as an experimental model of infection. These in vivo models are suggested to evaluate mutants of genes involved in the pathogenesis of Salmonella, since they represent an important tool for the understanding of the Salmonella-host interaction(AU)


Subject(s)
Animals , Mice , Salmonella typhimurium/pathogenicity , Genomic Islands/genetics , Microscopy, Electron, Transmission/methods , Mutation/genetics
6.
Article in English | WPRIM | ID: wpr-758914

ABSTRACT

Porcine proliferative enteropathy (PPE) caused by Lawsonia intracellularis (LI) is a global cause for substantial economic losses in the swine industry. Here, we constructed live attenuated Salmonella typhimurium (ST) mutant strains expressing and secreting 4 selected immunogenic LI antigens, namely, optA, optB, Lawsonia flagellin (LfliC), and Lawsonia hemolysin (Lhly); the resultant recombinant strains were designated Sal-optA, Sal-optB, Sal-LfliC, or Sal-Lhly, respectively. Using the BALB/c mouse model, we demonstrate that mice vaccinated once orally, either with a mixture of all 4 recombinant strains or with an individual recombinant strain, show significant (p < 0.05) production of LI-specific systemic immunoglobulin (Ig) G and mucosal IgA responses compared to the Salmonella alone group. Upon restimulation of vaccinated splenocytes with the LI-specific antigens, significant (p < 0.05) and comparable production of interferon-γ responses are found in all vaccinated groups, except the Sal-Lhly group, which shows non-significant levels. Challenge studies were performed in C57BL/6 vaccinated mice. On challenge with the LI (10(6.9) 50% tissue culture infectious dose) 14 days post-vaccination, 20% (1/5) of mice in all vaccinated groups, except Sal-Lhly group, show the presence of the LI-specific genomic DNA (gDNA) in stool samples. In contrast, 40% (2/5) and 60% (3/5) of mice vaccinated with the Sal-Lhly strain and the attenuated Salmonella alone, respectively, were found positive for the LI-specific gDNA. Furthermore, 0% mortality was observed in mice vaccinated against the ST challenge compared to the 30% mortality observed in the unvaccinated control group. In conclusion, we demonstrate that the Salmonella-based LI-vaccines induce LI-specific humoral and cell-mediated immunities, and encompass the potential to offer dual protection against PPE and salmonellosis.


Subject(s)
Animals , DNA , Flagellin , Immunity, Cellular , Immunoglobulin A , Immunoglobulins , Lawsonia Bacteria , Mice , Mortality , Salmonella Infections , Salmonella typhimurium , Salmonella , Swine
7.
Article in English | WPRIM | ID: wpr-758908

ABSTRACT

Gonadotropin-releasing hormone (GnRH) is secreted from the hypothalamus and anti-GnRH antibodies are not formed under normal conditions. However, administration an excess of recombinant GnRH protein results in the formation of anti-GnRH. We evaluated the efficacy of the recombinant Salmonella typhimurium flagellin fljB (STF2)-GnRH vaccine in inducing infertility in 17 intact male cats. The first vaccination and a boosting vaccine was injected for examination. Serum was obtained from blood collected at monthly intervals and anti-GnRH antibodies and testosterone concentrations were determined. Six months after the vaccination, testicular samples are obtained and used for histological examination. Compared with sham control group, the injection groups showed an increase in anti-GnRH antibody titers and testosterone concentrations tended to be reduced in the injection groups and increased in the control group. Histological evaluations and Johnsen's testicular biopsy scores revealed testicular hypoplasia in the 2 injection groups. Consequently, normal sexual maturation with sperm production was observed in the control group. In contrast, the cats that received the GnRH vaccine showed weak (2 of 7 cats) or moderate (4 out of 7 cats) dose-dependent infertility effects. On the basis of the results, the STF2-GnRH vaccine was identified to be effective in inducing infertility in male cats. The results of this study thus indicate the possibility of immunological castration targeting feral cats.


Subject(s)
Animals , Antibodies , Biopsy , Castration , Cats , Contraception, Immunologic , Fertility Agents , Flagellin , Gonadotropin-Releasing Hormone , Humans , Hypothalamus , Infertility , Male , Salmonella typhimurium , Sexual Maturation , Spermatozoa , Testis , Testosterone , Vaccination , Vaccines
8.
Rev. Soc. Bras. Med. Trop ; 52: e20180254, 2019. graf
Article in English | LILACS | ID: biblio-985162

ABSTRACT

Abstract INTRODUCTION: Antimicrobial resistance has been reported in the drugs used for the treatment of typhoid fever. The immunomodulatory substance β-glucan can be used as an alternative therapy as it potentiates host immunity. The aims of this study are to observe the effect of Candida albicans cell wall (CCW) extract towards host immunity (TCD8+ and TCD4+ cells in spleen, intestinal sIgA) and its capacity to kill Salmonella in the intestine and liver of typhoid fever mice models. METHODS: Typhoid fever mice models were created by infecting mice with S. Typhimurium orally. Mice were divided into four groups: the Non-Infected, Infected, CCW (infected mice treated with 300 µg CCW extract/mouse once a day), and Ciprofloxacin groups (infected mice treated with 15 mg/kg BW ciprofloxacin twice a day). RESULTS: Secretory IgA (sIgA) concentrations of mice in the CCW group remained unchanged. However, their TCD4+ and TCD8+ cells increased substantially compared to those in the Non-Infected group. In the Ciprofloxacin group, sIgA concentrations increased markedly compared to those in the Non-Infected and CCW groups; TCD4+ and TCD8+ cells also increased significantly compared to those in the Infected Group, but not significant compared to those in the CCW group. Colonization of S. Typhimurium in the intestine and liver decreased significantly in the CCW and Ciprofloxacin groups compared to that in the Infected group, with the lowest reduction being found in the Ciprofloxacin group. CONCLUSIONS The inhibition of S. Typhimurium colonization by CCW is associated with the increase in TCD4+ and TCD8+ cells.


Subject(s)
Animals , Male , Salmonella typhimurium/drug effects , Typhoid Fever/microbiology , Candida albicans/chemistry , beta-Glucans/pharmacology , Immunoglobulin A, Secretory , CD4-Positive T-Lymphocytes/microbiology , Ciprofloxacin , Microbial Sensitivity Tests , Cell Wall , CD8-Positive T-Lymphocytes/microbiology , Disease Models, Animal , Immunity, Cellular/immunology , Intestines/microbiology , Liver/microbiology , Mice , Mice, Inbred BALB C
9.
Pesqui. vet. bras ; 38(11): 2037-2043, Nov. 2018. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-976392

ABSTRACT

The aim of the present study was to investigate the presence of Salmonella spp. in samples collected from beef meat at three points of the slaughter line (after skinning, washing and cooling) at three slaughterhouses in Brazil that export meat. Detection was based on ISO 6579:2002 and confirmed by PCR and qPCR. The isolates were typified using slide agglutination tests and PFGE. The antibiotic sensitivity profile was determined using the disk diffusion method. Contamination was detected in only one slaughterhouse. The overall frequency of contamination by Salmonella spp. was 6.7% of carcasses (6/90) and 2.6% of carcass surface samples (7/270). All isolates were confirmed by PCR and qPCR. The serological analysis and the PFGE showed a single profile: Typhimurium. The strains demonstrated 100% susceptibility to ampicillin, cefotaxime, ciprofloxacin, chloramphenicol, gentamicin and tetracycline. Positive carcasses after cooling pose a direct risk to consumers, since the meat is considered ready to be marketed after this process.(AU)


O objetivo deste trabalho foi investigar a presença de Salmonella spp. em amostras coletadas de carcaças de bovinos, em três pontos da linha de abate (após a esfola, lavagem e refrigeração) de três frigoríficos exportadores no Brasil. A detecção foi realizada pela ISO 6579:2002, e confirmada por PCR e qPCR. Os isolados foram tipificados por testes de soroaglutinação e PFGE e avaliado o perfil de sensibilidade aos antibióticos pelo método de difusão em disco. A contaminação foi detectada em apenas um abatedouro-frigorífico. As contaminações das carcaças (n=90) e amostras de carne (n=270) por Salmonella spp. foram 6 (6,7%) e 7 (2,6%), respectivamente. Todos os isolados foram confirmados por PCR e qPCR. A análise sorológica e o PFGE mostraram um único perfil: Typhimurium. As cepas apresentaram 100% de suscetibilidade à ampicilina, cefotaxima, ciprofloxacina, cloranfenicol, gentamicina e tetraciclina. As carcaças positivas após a refrigeração apresentam um risco direto para o consumidor, uma vez que, após este processo, a carne está pronta para ser comercializada.(AU)


Subject(s)
Animals , Cattle , Salmonella Infections , Salmonella typhimurium , Drug Resistance, Microbial , Cattle Diseases/microbiology , Cattle Diseases/epidemiology , Meat Industry , Red Meat/microbiology , Food Microbiology , Brazil/epidemiology , Abattoirs
10.
Braz. j. infect. dis ; 22(5): 424-432, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-974235

ABSTRACT

ABSTRACT Introduction: Nontyphoidal Salmonella serotypes are the main cause of human food-borne infection, including several hospitalization cases in the developing countries. Aim: To detect the main serotypes and to characterize the antibiotic resistance of human non-enteric and enteric nontyphoidal Salmonella from clinical isolates in Brazil. Methods: Salmonella serotypes were identified by microbiological and molecular methods. Susceptibility testing to antibiotics was performed by agar disk diffusion. Real-time PCRs were carried out for the detection of the genus Salmonella as well as serotypes Typhimurium and Enteritidis. Results: A total of 307 nontyphoidal Salmonella were isolated from 289 different patients in a reference laboratory (LACEN-RS) from Southern Brazil in a six-year period (2010-2015). There were 45 isolates from emerging cases and 244 from sporadic cases in hospitalized patients. Non-enteric isolates were detected in 42.6% of the patients from sources such as urine, blood and other clinical fluids. Serological and PCR-specific tests demonstrated that Typhimurium (48.4%) and Enteritidis (18.3%) were the most frequent serotypes. Typhimurium isolates were generally resistant to three or more antibiotic classes, while Enteritidis isolates to one or two classes. Typhimurium was the most frequent serotype in all samples (48.4%), mainly among the hospitalized patients (55.6%), and presented the highest rates of multidrug resistance (59.3% of the isolates of this serotype). Further, the prevalence of this serotype increased along the years of the study in comparison to other nontyphoidal Salmonella serotypes. Conclusion: Greater public health attention should be given to prevent salmonellosis in the community and in hospital settings to reduce the rates of Typhimurium strains with multidrug resistance.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Young Adult , Salmonella Infections/microbiology , Salmonella Infections/epidemiology , Salmonella typhimurium/drug effects , Drug Resistance, Multiple, Bacterial , Hospitalization/statistics & numerical data , Salmonella enteritidis/isolation & purification , Salmonella enteritidis/drug effects , Salmonella typhimurium/isolation & purification , Time Factors , Brazil/epidemiology , Microbial Sensitivity Tests , Serotyping , Cross Infection/microbiology , Cross Infection/epidemiology , Prevalence , Real-Time Polymerase Chain Reaction , Serogroup , Anti-Bacterial Agents/pharmacology
11.
Braz. j. biol ; 78(2): 345-350, May-Aug. 2018. tab
Article in English | LILACS | ID: biblio-888873

ABSTRACT

Abstract Salacia crassifolia (Mart. Ex. Schult.) G. Don. is a bush which belongs to Celastraceae family and occurs specially in Brazilian Cerrado. Its leaves, stem, seeds and fruits are popularly used for several medicinal purposes, such as antitumoral, antirheumatic, anti-inflammatory and antimicrobial. In this study, the mutagenic and antimutagenic activities of S. crassifolia stem bark fractions (hexane, ethyl acetate and hydroalcoholic) were evaluated by the Ames mutagenicity assay in Salmonella typhimurium TA98 and TA100 strains. By the obtained results, all S. crassifolia fractions did not significantly increase the number of prototrophic revertants for histidine (His+) in both S. typhimurium strains tested (p > 0.05), suggesting absence of mutagenicity. Regarding antimutagenicity, the fractions ethyl acetate and hydroalcoholic significantly decreased the number of His+ revertants colonies induced by positive control for strain TA98 (p < 0.05), demonstrating protection against mutagenicity induced by 4-nitroquinolile1-oxide, whereas the hexane fraction did not show antimutagenic effect in this strain. In the TA100 strain, all fractions of S. crassifolia protected DNA against the harmful action of sodium azide, and the hexane fraction exhibited the greatest protection in this work. Thus, it's possible conclude that the fractions of S. crassifolia tested in this study could be used in chemoprevention.


Resumo Salacia crassifolia (Mart. Ex. Schult.) G. Don. é uma árvore que pertence à família Celastraceae e ocorre especialmente no Cerrado Brasileiro. Suas folhas, caule, sementes e frutos são popularmente utilizados para vários fins medicinais, tais como antitumoral, antirreumático, anti-inflamatório e antimicrobiano. Neste estudo, nós avaliamos as atividades mutagênica e antimutagênica de frações da casca do caule de S. crassifolia (hexânica, acetato de etila e hidroalcoólica) pelo ensaio de mutagenicidade de Ames em Salmonella typhimurium, cepas TA98 e TA100. Pelos resultados obtidos todas as frações de S. crassifolia não aumentaram significativamente o número de revertentes prototróficas para histidina (His+) em ambas as cepas de S. typhimurium testadas (p > 0.05), sugerindo ausência de mutagenicidade. Em relação à antimutagenicidade, as frações acetate de etila e hidroalcoólica reduziram significativamente o número de colônias revertentes His+ induzidas pelo controle positive para a cepa TA98 (p < 0.05), demonstrando sua ação protetora contra a mutagenicidade induzida por 4-nitroquinolile1-oxide, enquanto a fração hexânica não demonstrou efeito antimutagênico nesta cepa. Na cepa TA100, todas as frações de S. crassifolia protegeram o DNA contra a ação lesiva de azida sódica, e a fração hexânica exibiu a maior proteção desse trabalho. Assim, concluímos que as frações de S. crassifolia testadas neste estudo poderiam ser utilizadas em quimioprevenção.


Subject(s)
Antimutagenic Agents/pharmacology , Salacia/chemistry , Mutagens/toxicity , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics , Plant Extracts/toxicity , Plant Extracts/pharmacology , Mutagenicity Tests , 4-Nitroquinoline-1-oxide/toxicity
12.
Article in English | WPRIM | ID: wpr-758849

ABSTRACT

Salmonella is an intracellular pathogen with a cellular infection mechanism similar to that of Brucella, making it a suitable choice for use in an anti-Brucella immune boost system. This study explores the efficacy of a Salmonella Typhimurium delivery-based combination vaccine for four heterologous Brucella antigens (Brucella lumazine synthase, proline racemase subunit A, outer-membrane protein 19, and Cu/Zn superoxide dismutase) targeting brucellosis in goats. We inoculated the attenuated Salmonella delivery-based vaccine combination subcutaneously at two different inoculation levels; 5 × 10⁹ colony-forming unit (CFU)/mL (Group B) and 5 × 10¹⁰ CFU/mL (Group C) and challenged the inoculations with virulent Brucella abortus at 6 weeks post-immunization. Serum immunoglobulin G titers against individual antigens in Salmonella immunized goats (Group C) were significantly higher than those of the non-immunized goats (Group A) at 3 and 6 weeks after vaccination. Upon antigenic stimulation, interferon-γ from peripheral blood mononuclear cells was significantly elevated in Groups B and C compared to that in Group A. The immunized goats had a significantly higher level of protection as demonstrated by the low bacterial loads in most tissues from the goats challenged with B. abortus. Relative real-time polymerase chain reaction results revealed that the expression of Brucella antigens was lower in spleen, kidney, and lung of immunized goats than of non-immunized animals. Also, treatment with our combination vaccine ameliorated histopathological lesions induced by the Brucella infection. Overall, the Salmonella Typhimurium delivery-based combination vaccine was effective in delivering immunogenic Brucella proteins, making it potentially useful in protecting livestock from brucellosis.


Subject(s)
Animals , Bacterial Load , Brucella abortus , Brucella Vaccine , Brucella , Brucellosis , Goats , Immunoglobulin G , Kidney , Livestock , Lung , Proline , Real-Time Polymerase Chain Reaction , Salmonella typhimurium , Salmonella , Spleen , Stem Cells , Superoxides , Vaccination
13.
Article in English | WPRIM | ID: wpr-758812

ABSTRACT

An anti-Brucella vaccine candidate comprised of purified Brucella lipopolysaccharide (LPS) and a cocktail of four Salmonella Typhimurium (ST)-Brucella vectors was reported previously. Each vector constitutively expressed highly conserved Brucella antigens (rB), viz., lumazine synthase (BLS), proline racemase subunit A, outer membrane protein-19 (Omp19), and Cu-Zn superoxide dismutase (SOD). The present study determined a relative level of protection conferred by each single strain. Upon virulent challenge, the challenge strain was recovered most abundantly in non-immunized control mice, with the ST-Omp19-, ST-BLS-, LPS-, and ST-SOD-immunized mice showing much less burden. Indirect enzyme-linked immunosorbent assay-based assay also confirmed the induction of antigen-specific immunoglobulin G for each antigen delivered. In a route-wise comparison of the combined vaccine candidate, intraperitoneal (IP), intramuscular (IM), and subcutaneous immunizations revealed an indication of highly efficient routes of protection. Splenocytes of mice immunized via IM and IP routes showed significant relative expression of IL-17 upon antigenic pulsing. Taken together, each of the Brucella antigens delivered by ST successfully induced an antigen-specific immune response, and it was also evident that an individual antigen strain can confer a considerable degree of protection. More effective protection was observed when the candidate was inoculated via IP and IM routes.


Subject(s)
Animals , Brucella , Brucellosis , Immunization , Immunoglobulin G , Interleukin-17 , Membranes , Mice , Proline , Salmonella typhimurium , Salmonella , Superoxide Dismutase , Vaccination
14.
Chonnam Medical Journal ; : 17-23, 2018.
Article in English | WPRIM | ID: wpr-787262

ABSTRACT

Salmonella enterica serovar Typhimurium is one of the most important bacterial pathogens causing diarrhea. The resistance of S. typhimurium to antimicrobial agents, which has recently been isolated from patients, is causing serious problems. We investigated the effects of salicylic acid (Sal) and acetyl salicylate (AcSal) on the susceptibility of S. typhimurium to cephalosporin antibiotics, which are known to increase resistance to cephalosporin and quinolone antibiotics. The MIC of cephalosporin antibiotics was higher than that of the media without Sal. The rate of accumulation of ethidium bromide (EtBr) in the bacteria by the outer membrane protein (Omp) was not different from that of the bacteria cultured in the medium containing Sal. However, Carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an inhibitor of bacterial efflux pumps, significantly reduced the rate of accumulation of EtBr in bacteria cultured on Sal containing medium. In the medium containing CCCP, the MIC of the antimicrobial agent tended to decrease as compared with the control. In addition, the MIC of the bacteria treated with CCCP and Sal was higher than that of the antimicrobial agent against the CCCP treated experimental bacteria. These results suggest that Sal decreases the expression of OmpF in the Omp of S. typhimurium and reduces the permeability of cephalosporin antibiotics to bacteria, which may induce tolerance to cephalosporin antibiotics.


Subject(s)
Anti-Bacterial Agents , Anti-Infective Agents , Bacteria , Carbonyl Cyanide m-Chlorophenyl Hydrazone , Cephalosporin Resistance , Cephalosporins , Diarrhea , Ethidium , Humans , Membrane Proteins , Permeability , Salicylic Acid , Salmonella enterica , Salmonella typhimurium , Salmonella , Serogroup
15.
Arq. bras. med. vet. zootec. (Online) ; 70(2): 637-640, mar.-abr. 2018.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-910980

ABSTRACT

The maintenance of wild animals in captivity can be a source for transmission of infectious and zoonotic diseases. In February 2016, blue-fronted amazon parrots that were kept at the Centro de Reabilitação de Animais Silvestres (CRAS) of Campo Grande - MS died suddenly. The specimens were sent to the Universidade Federal de Mato Grosso do Sul (UFMS), Faculdade de Medicina Veterinária e Zootecnia (FAMEZ) to be necropsied. Anatomopathological exams were performed and organ fragments from all systems were collected for histopathological exams. Liver and spleen fragments were also collected for bacteriological exams. Histopathological exam revealed bacterial aggregates distributed through the organs. Bacteriological exam isolated Salmonella spp. from the fragments of liver and spleen. The confirmation of the genus was made by serum agglutination on slide and by the polymerase chain reaction (PCR). The genetic sequencing identified the sample as Salmonella Typhimurium.(AU)


Subject(s)
Animals , Amazona/microbiology , Salmonella Infections/microbiology , Salmonella typhimurium/pathogenicity , Polymerase Chain Reaction/veterinary
16.
Braz. J. Pharm. Sci. (Online) ; 54(1): e17229, 2018. tab, graf
Article in English | LILACS | ID: biblio-951909

ABSTRACT

ABSTRACT The present study evaluated the antibacterial and antibiofilm activity of carvacrol against Salmonella Typhimurium. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined and the time-kill curve and scanning electron microscopy (SEM) were performed to evaluate antibacterial activity. Antibiofilm activity was evaluated by quantifying total biomass using crystal violet assay, and metabolic activity was determined using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The action of carvacrol against preformed biofilm on polypropylene and stainless steel was also evaluated by colony counting and SEM. The MIC and MBC was 312 µg mL-1. Carvacrol at MIC and 2 x MIC eliminated cells after 6 and 1 h of treatment, respectively, as exhibited in the time-kill curve. The greatest reduction in biofilm biomass and metabolic activity was 1,719 OD550 and 0,089 OD550 respectively, both at 4 x MIC of carvacrol. In carvacrol treated biofilms of S. Typhimurium on polypropylene, a reduction of 5.12 log was observed with 4 x MIC, while on stainless steel, carvacrol at 4 x MIC reduced bacterial counts by 5 log. The results showed that carvacrol exhibits antibacterial activity and can be used as an alternative for the control of S. Typhimurium biofilms.


Subject(s)
Salmonella typhimurium/immunology , Biofilms , Anti-Bacterial Agents/analysis , Microbial Sensitivity Tests/instrumentation
17.
Rev. chil. infectol ; 34(4): 359-364, ago. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-899724

ABSTRACT

Resumen Introducción: Salmonella sp puede causar infecciones asintomáticas, gastroenteritis, bacteriemia e infecciones focales como meningitis y osteomielitis. Objetivo: Describir aspectos microbiológicos y clínicos de las infecciones por Salmonella spp en niños en un hospital de referencia pediátrico Centro Hospitalario Pereira Rossell. Montevideo Uruguay. Material y Métodos: Estudio descriptivo y retrospectivo de pacientes en quienes se aislara Salmonella spp en el período 1 de enero de 2005 al 31 de diciembre de 2010. Resultados: Se aisló Salmonella spp en 46 niños menores de 15 años. Dieciocho eran menores de 2 años y 5 niños menores de tres meses. 24% de los pacientes presentaba factores de riesgo (infección por VIH; enfermedad hemato-oncológica, desnutrición) y co-morbilidades (bajo peso al nacer y neumonía). No hubo fallecidos. Los serotipos más frecuentes fueron: Typhimurium y Enteritidis. La mayoría de las cepas eran sensibles a ampicilina y cefalosporinas de tercera generación. Discusión: La presentación clínica predominante fue diarrea con sangre, no se presentaron brotes. Basados en los perfiles de susceptibilidad antimicrobiana, se pueden mantener las recomendaciones hasta el momento sugeridas. Conclusiones: Se debe tener en cuenta la infección por Salmonella sp en niños febriles con riesgo de enfermedad bacteriana invasora, con o sin focalidad.


Background: Salmonella can cause asymptomatic infections, diarrhea, bacteremia and focal infections such as meningitis and osteomyelitis. Aim: To describe clinical and microbiological aspects of infections by Salmonella spp. in children in a pediatric referral hospital: Centro Hospitalario Pereira Rossell, in Montevideo, Uruguay. Materials and Methods: Descriptive and retrospective study of 46 patients, from which Salmonella spp was isolated between January 1, 2005 and December 31, 2010. Results: Salmonella spp was isolated in 46 children younger than 15 years old. 18 were below 2 years old and 5 children below three months. 24% of the children had risk factors, such as HIV infection, oncological diseases and malnutrition; low birth weight and pneumonia were associated conditions. No deaths were reported. The serotypes more frequently found were: Typhimurium and Enteritidis. Most of the strains were susceptible to ampicillin and third generation of cephalosporins. Discussion: Diarrhea with blood was the predominant clinical presentation, and there were no outbreaks. Typhimurium and Enteritidis were the most common serotypes. Based on the profiles of susceptibility antimicrobial, we could maintain the same recommendations until the moment suggested. Conclusions: we must consider the Salmonella infection in febrile children under risk of an invasive bacterial disease, with or without focal infection.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Salmonella Infections/microbiology , Salmonella enteritidis/isolation & purification , Salmonella Infections/epidemiology , Salmonella typhimurium/isolation & purification , Time Factors , Uruguay/epidemiology , Intensive Care Units, Pediatric , Comorbidity , HIV Infections/epidemiology , Retrospective Studies , Risk Factors , Diarrhea/microbiology , Diarrhea/epidemiology
18.
Pesqui. vet. bras ; 37(4): 379-384, Apr. 2017. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-895421

ABSTRACT

The role of Escherichia coli in healthy microbiota of psittacine is controversial, and the presence of Salmonella sp. indicates possible disease. Therefore, this study aimed to identify the presence of E. coli and Salmonella spp. in a psittacine pet that died in Fortaleza, Brazil, correlating pathogenicity aspects of the isolates through the evaluation of lesions and antimicrobial susceptibility. Psittacine pets sent to the Laboratory of Ornithological Studies, State University of Ceará, that died in 2014 and 2015 were necropsied. Fragments of liver, kidneys, intestine, lung, heart, spleen and brain were collected for microbiological and histopathological analyses. Scores were attributed to lesions and isolated strains submitted to antimicrobial susceptibility test. From the seventy necropsied birds, nineteen were positive for E. coli and one for Salmonella Typhimurium. Congestive lesions and lymphoplasmocitic inflammatory infiltrate were observed varying from light to moderate and were the main findings. In the analyzed strains, multidrug resistance against different groups of antibiotics was observed. In conclusion, according to the results, E. coli strains and the Salmonella Typhimurium isolate produced significant lesions in the psittacine pets, and multidrug resistance may hinder treatments with antibiotics used in avian pet medicine.(AU)


A participação de Escherichia coli na microbiota saudável de Psicittaciformes e a de Salmonella spp. já indica possível doença. O objetivo deste estudo foi pesquisar a presença de E. coli e Salmonella spp. em psittaciformes de companhia na cidade de Fortaleza/Ceará, traçando os aspectos de patogenicidade destas cepas através das lesões e da sensibilidade antimicrobiana. Foram necropsiados os psittaciformes de companhia encaminhados ao Laboratório de Estudos Ornitológicos da Universidade Estadual do Ceará durante o período de 2014 a 2015. No momento da necropsia foram coletados fragmentos de fígado, rins, intestino, pulmão, coração, baço e encéfalo para posterior processamento microbiológico e histopatológico. As lesões foram graduadas e as cepas isoladas submetidas a antibiograma. Das setenta aves necropsiadas, dezenove foram positivas para E. coli e apenas uma para Salmonella Typhimurium. As lesões de congestão e infiltrado inflamatório linfoplasmocitário variaram de leve a moderado, e foram as principais lesões encontradas. Nas cepas analisadas foi constatada multiresistência a diferentes grupos de antibióticos testados. De acordo com os achados, pode-se concluir que os isolados de E. coli e Salmonella Typhimurium produziram lesões significativas em psittaciformes em Fortaleza, Brasil, e a multirresistência pode dificultar o tratamento com antibióticos usados na clínica de aves de companhia.(AU)


Subject(s)
Animals , Psittaciformes/microbiology , Salmonella typhimurium , Escherichia coli
19.
Article in English | WPRIM | ID: wpr-115138

ABSTRACT

The present study developed an oral hepatocyte growth factor (HGF) gene therapy strategy for gastric ulcers treatment. An attenuated Salmonella typhimurium that stably expressed high HGF (named as TPH) was constructed, and the antiulcerogenic effect of TPH was evaluated in a rat model of gastric ulcers that created by acetic acid subserosal injection. From day 5 after injection, TPH (1 × 10⁹ cfu), vehicle (TP, 1 × 10⁹ cfu), or sodium bicarbonate (model control) was administered orally every alternate day for three times. Then ulcer size was measured at day 21 after ulcer induction. The ulcer area in TPH-treated group was 10.56 ± 3.30 mm², which was smaller when compared with those in the TP-treated and model control groups (43.47 ± 4.18 and 56.25 ± 6.38 mm², respectively). A higher level of reepithelialization was found in TPH-treated group and the crawling length of gastric epithelial cells was significantly longer than in the other two groups (P < 0.05). The microvessel density in the ulcer granulation tissues of the TPH-treated rats was 39.9 vessels/mm², which was greater than in the TP-treated and model control rats, with a significant statistical difference. These results suggest that TPH treatment significantly accelerates the healing of gastric ulcers via stimulating proliferation of gastric epithelial cells and enhancing angiogenesis on gastric ulcer site.


Subject(s)
Acetic Acid , Animals , Epithelial Cells , Genetic Therapy , Granulation Tissue , Hepatocyte Growth Factor , Hepatocytes , Microvessels , Models, Animal , Rats , Salmonella typhimurium , Salmonella , Sodium Bicarbonate , Stomach Ulcer , Ulcer
20.
Article in English | WPRIM | ID: wpr-122305

ABSTRACT

The probiotic properties of Enterococcus (E.) faecalis PSCT3-7, a new strain isolated from the intestines of pigs fed dietary fiber containing 50% sawdust, were investigated. E. faecalis PSCT3-7 tolerated a pH range of 3 to 8 and 0.3% bile salts, and it inhibited the growth of Salmonella Typhimurium in a concentration-dependent manner. In addition, E. faecalis showed resistance to several antibacterial agents. Vermiculite, a nutrient and microbial carrier, increased the bile tolerance of the strain. Scanning electron microscope images revealed good adsorption of E. faecalis PSCT3-7 onto vermiculite. E. faecalis PSCT3-7 represents a potential probiotic candidate to administer with vermiculite to swine.


Subject(s)
Adsorption , Anti-Bacterial Agents , Bile , Bile Acids and Salts , Dietary Fiber , Enterococcus faecalis , Enterococcus , Hydrogen-Ion Concentration , Intestines , Probiotics , Salmonella typhimurium , Swine
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