Study the Ability of Salmonella typhimiurm to Induce Cytokine TNFα in Mice Treated with Olive Leaves Extract and Ciprofloxacin.

TNF-α is a type of cytokine that is produced by inflammatory cells. These inflammatory cells produce cytokines such as TNF-α, IFN- γ, IL-1, etc. Ciprofloxacin is the last drug of choice to clear the infection. Ciprofloxacin, a grace inhibitor, kills bacteria by inducing chromosome fragmentation and reactive oxygen species (ROS) in the bacterial cell. This study was designed to investigate the ability of Salmonella typhimiurm to induce TNF-α in cells. 30 NMRI mice from both genders were divided randomly into 3 groups (n=10) and treated as follows: The first group was intraperitoneally (I.P.) injected with a 0.1 ml/4×108 CFU/ ml bacterial suspension of S. typhimiurm as a positive control. The second group was injected (I.P.) with S. typhimiurm 0.1 ml (4×108 CFU/ml and then injected with 30 mg/kg/0.3 ml of CiprofloxacinCiprofloxacin intramuscular (I.M.). The olive leaf alcoholic extract was given to the third group through a gavage tube for two weeks before giving I/P 0.1 ml/4×108 CFU/ml S. typhimiurm. Afterward, they were post-treated with 30 mg/kg/0.3 ml of olive leaf extract orally by gavage tube until the end of the experiment (30 days). The recorded data from group 1 showed heavy deposition of TNF-α marker in the spleen and liver, and examination showed dark brown cellular components. Also, in the second group, the spleen and liver tissue sections showed heavy deposition of TNF-α marker; other sections showed moderated deposition of TNF-α marker. In the third group, TNF marker was found in small amounts or not in tissue samples from the spleen and liver. Histopathological examination of infected 1st group liver and spleen tissue sections shows lobular hepatic necrosis with mononuclear cells. Aggregation manifests as granuloma lesions, particularly lymphocytes in the portal area around the bile duct and blood vessels, with the proliferation of macrophages known as kupffer cells and depletion of white pulp in spleen tissue when compared to the second and third groups, which demonstrated moderated lesions in infected and treated mice. The results showed that olive leaf extract reduces the infection of Salmonella typhimiurm in the pre and post-treated groups better than CiprofloxacinCiprofloxacin.

Beneficial effect of immunobiotic strains on attenuation of Salmonella induced inflammatory response in human intestinal epithelial cells.

Probiotic bacteria have the ability to modulate host immune responses and have potent therapeutic functional effects against several diseases, including inflammatory diseases. However, beneficial effects of probiotics are strain specific and their interactions with host immune cells to modulate inflammatory response are largely unknown. Intestinal epithelial cells (IECs), which are the first line of defense against invading pathogens, and connects between commensals/probiotics and immune system; therefore, in this study, we used human IECs to assess the probiotic effects of three selected Lactobacillus strains in vitro. An HT-29 colonic epithelial cell and HT-29/blood mononuclear cells co-culture system were stimulated with Lactobacillus followed by Salmonella for different hours, after which the mRNA level of cytokines, ß-defensin-2 and negative regulators for TLR signaling and protein levels of ZO-1 and IκB-α were analyzed by real-time polymerase chain reaction and western blot analysis. L. brevis decreased Salmonella induced IL-6, IL-8, MCP-1 and IL-1ß levels, whereas L. pentosus suppressed IL-6 and MCP-1 in HT-29 cells. Moreover, L. brevis was able to increase the mRNA levels of A20, Tollip, SIGIRR and IRAKM, while L. pentosus reduced the levels of A20, and IRAKM in response to Salmonella. In addition, decrease in protein level of TNF-α and increase in mRNA level of IL-10 was observed in L. brevis and L. pentosus treated HT-29 cells. Lactobacillus strains were differentially modulated ZO-1 and p-IκB-α in HT-29 cells treated with Salmonella. Overall, the results of this study indicate that Lactobacillus strains attenuate Salmonella induced inflammatory responses through beneficial modulation of TLR negative regulators and the NF-κB pathway.

Anti-virulence activities of biflavonoids from Mesua ferrea L. flower.

Based on the anti-virulence activity on Salmonella, the ethyl acetate extract (EAE) of Mesua ferrea flower was investigated for its chemical constituents. Ten purified compounds were identified and assayed for their inhibitory activity against Type III secretion system (T3SS) by polyacrylamide gel electrophoresis (SDS-PAGE) and Western blots experiments. We found the biflavonoids, rhusflavanone and mesuaferrone B, exhibited inhibitory effects on the secretion of Salmonella pathogenicity island 1 (SPI-1) effector proteins (SipA, B, C and D) without effecting the bacterial growth. In addition, 5, 6, 6'-trihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid (6) is a new natural product from M. ferrea flower.

Lactic acid fermentation of legume seed sprouts as a method of increasing the content of isoflavones and reducing microbial contamination.

Legume seeds and sprouts are a rich source of phytoestrogens in the form of isoflavonoids. For the first time, lactic acid fermentation of four types of legume sprouts was used to increase the content of isoflavonoids and microbiological safety. After germination, the highest content of isoflavonoids was observed in the clover and chickpea sprouts, which amounted to 1.1 g/100 g dw., whereas the lactic acid fermentation allowed the increase to as much as 5.5 g/100 g dw. The most beneficial properties were shown by fermented chickpea sprouts germinated in blue light. During fermentation the number of lactic acid bacteria increased by 2 Log10 CFU/mL (LU), whereas mold decreased by 1 LU, E. coli and Klebsiella sp. by 2 LU, Salmonella sp. and Shigella sp. did not occur after fermentation, similar to Staphylococcus epidermidis, while S. aureus and S. saprophyticus decreased by 3 LU and in some trials were not detected.

Tolerance to benzalkonium chloride and antimicrobial activity of Butia odorata Barb. Rodr. extract in Salmonella spp. isolates from food and food environments.

Salmonellosis, caused by the consumption of contaminated foods, is a major health problem worldwide. The aims of this study were to assess the susceptibility of Salmonella spp. isolates to benzalkonium chloride (BC) disinfectant and the antimicrobial activity of Butia odorata Barb. Rodr. extract against the same isolates from food and food environments. Moreover, phenotypic and genotypic resistance profiles, the presence of virulence genes and biofilm forming ability were determined. The minimum inhibitory concentration (MIC) of B. odorata extract against Salmonella spp. ranged from 10 to >19 mg.mL-1. Resistance to ampicillin, streptomycin, nalidixic acid, sulfonamide, trimethoprim/sulfamethoxazole, trimethoprim, tetracycline, and chloramphenicol was observed. In addition, multidrug resistance was observed in seven isolates (26.92%). The MIC of BC ranged from 32 to 64 mg.L-1, higher concentrations in comparison with wild-type MICs, and therefore were considered tolerant. Several resistance genes were detected, of which the most common were aadA, qacEΔ1, blaTEM, int1, sul1, and tetA. All isolates carried at least one virulence gene and produced biofilms on stainless steel surfaces at 10 and 22 °C. On the other hand, the B. odorata extract showed activity against Salmonella spp., and it has the potential to be used as a natural antimicrobial to control this important foodborne pathogen, despite its virulence potential and antimicrobial resistance profile.

Salmonella infection - prevention and treatment by antibiotics and probiotic yeasts: a review.

Global Salmonella infection, especially in developing countries, is a health and economic burden. The use of antibiotic drugs in treating the infection is proving less effective due to the alarming rise of antibiotic-resistant strains of Salmonella, the effects of antibiotics on normal gut microflora and antibiotic-associated diarrhoea, all of which bring a growing need for alternative treatments, including the use of probiotic micro-organisms. However, there are issues with probiotics, including their potential to be opportunistic pathogens and antibiotic-resistant carriers, and their antibiotic susceptibility if used as complementary therapy. Clinical trials, animal trials and in vitro investigations into the prophylactic and therapeutic efficacies of probiotics have demonstrated antagonistic properties against Salmonella and other enteropathogenic bacteria. Nonetheless, there is a need for further studies into the potential mechanisms, efficacy and mode of delivery of yeast probiotics in Salmonella infections. This review discusses Salmonella infections and treatment using antibiotics and probiotics.

Tuberculosis in an autosomal recessive case of chronic granulomatous disease due to mutation of the NCF1 gene

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Effect of water-soluble fraction of cherry tomatoes on the adhesion of probiotics and Salmonella to intestinal epithelial cells.

BACKGROUND: Tomato is one of the most consumed vegetables in the world and contains many valuable nutritional components. Here we investigate the prebiotic effects of cherry tomatoes for improving gut health. RESULTS: Water-soluble dietary fiber was prepared from fresh and processed (heat treatment at 80 °C for 15 min) cherry tomato samples, each with and without Viscozyme L treatment. In the adhesion assays, all water-soluble dietary fiber samples improved adhesion of probiotics (Lactobacillus rhamnosus and Bifidobacterium bifidum) to intestinal epithelial cells (Caco-2 cells). Heat treatment in the preparation of juice from cherry tomatoes showed no significant effect on the adhesion of probiotics to Caco-2 cells. The oligofructose content of samples affected the intestinal adhesion of probiotic bacteria, with higher oligosaccharide concentrations associated with greater adhesion of probiotics and more inhibition of the adhesion of pathogens to Caco-2 cells. CONCLUSION: The present results suggest that cherry tomato can act as a prebiotic, with oligofructose potentially being one of its major prebiotic components.

The iron link between malaria and invasive non-typhoid Salmonella infections.

Epidemiological studies have demonstrated an association between malaria and invasive non-typhoid Salmonella (NTS) infections, especially in children. We explore the role of iron as a possible cofactor in this association. Malarial disease, among others, is associated with enhanced erythrophagocytosis and inflammation, which increases the iron content of macrophages and thereby also the survival of Salmonella spp. within macrophages. Whether iron supplementation programs augment the risk of invasive NTS infections in malaria-endemic regions is an important global health issue that still needs to be determined.

Use of Carbapenems against clinical, nontyphoid Salmonella isolates: results from in vitro and in vivo animal studies.

The emergence of multidrug-resistant Salmonella isolates has created the need for new therapeutic agents. We evaluated the intracellular activity of four carbapenem compounds against clinical nontyphoid Salmonella (NTS) isolates in vitro and ex vivo. Subsequently, the efficacy of carbapenem treatment against selected Salmonella isolates in vivo was assessed using a murine peritonitis model. The MIC(50) and MIC(90) for doripenem, ertapenem, imipenem, and meropenem against 126 NTS isolates were found to be 0.062 and 0.062, 0.015 and 0.015, 0.5 and 1, and 0.031 and 0.031 µg/ml, respectively. The intracellular killing effect of ertapenem was sustained for 24 h and was superior to that of imipenem, meropenem, and doripenem; its effect was comparable to that of ceftriaxone. Ertapenem demonstrated an excellent pharmacokinetic profile with a percent time above the MIC of 75.5% and an area under the concentration-time curve/MIC ratio of 20,733. When peritoneal exudate cells were examined directly ex vivo from mice with Salmonella-induced peritonitis, cells from mice treated with ertapenem and ceftriaxone had intracellular and extracellular bacterial counts reduced 10(2)- to 10(4)-fold and exhibited killing effects similar to each other. The survival rates of mice inoculated with 1 × 10(5) and 10(6) CFU of a ceftriaxone-susceptible Salmonella isolate that were subsequently treated with ertapenem or ceftriaxone were 100% and 90%, respectively. When mice were inoculated with 5 × 10(4) and 10(5) CFU of a ceftriaxone-resistant and ciprofloxacin-resistant Salmonella isolate, mice treated with ertapenem had a higher survival rate than mice treated with ceftriaxone (70% versus 0% and 50% versus 0%, respectively; P < 0.001). Our results suggest that ertapenem is at least as effective as ceftriaxone in treating murine Salmonella infections and show that further clinical investigations on the potential use of ertapenem in treatment of human Salmonella infections are warranted.

Enteric pathogens associated with childhood diarrhea in Tripoli-Libya.

Stool samples from children < 5 years of age with diarrhea (N = 239) were examined for enteric pathogens using a combination of culture, enzyme-immunoassay, and polymerase chain reaction methods. Pathogens were detected in 122 (51%) stool samples; single pathogens were detected in 37.2% and co-pathogens in 13.8% of samples. Norovirus, rotavirus, and diarrheagenic Escherichia coli (DEC) were the most frequently detected pathogens (15.5%, 13.4%, and 11.2%, respectively); Salmonella, adenovirus, and Aeromonas were detected less frequently (7.9%, 7.1%, and 4.2%). The most commonly detected DEC was enteroaggregative E. coli (5.4%). Resistance to ≥ 3 antimicrobials was observed in 60% (18/30) of the bacterial pathogens. Salmonella resistance to ciprofloxacin (63.1%) has become a concern. Enteric viral pathogens were the most significant causative agents of childhood diarrhea in Tripoli. Bacterial pathogens were also important contributors to pediatric diarrhea. The emergence of ciprofloxacin-resistant Salmonella represents a serious health problem that must be addressed by Libyan health authorities.

Quiste esplénico sobreinfectado en paciente inmunocompetente / Superinfected splenic cyst in immunocompetent patient

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Antimicrobial therapy of salmonelloses--current state and perspectives.

Salmonellosis in humans is most often manifested as a self-limiting gastroenteritis. Antimicrobial therapy is superfluous in the milder forms of the disease and in Salmonella carriage but can be life saving for patients with septic salmonellosis and patients at risk of extraintestinal dissemination of the infection. The therapeutic approach is based on the clinical course of the disease and the patient's immune reactivity. Antimicrobial therapy is usually initiated before the in vitro susceptibility tests of the isolate become available. Currently, the drugs of choice for empiric treatment of acute infectious diarrhea, in which Salmonella spp are etiologically implicated, are fluoroquinolones in adults and third generation cephalosporins in children. Alternative treatment may use azithromycin and imipenem in life-threatening systemic Salmonella infections. Aminoglycosides are considered ineffective in gastrointestinal salmonelloses. The emerging resistance to fluoroquinolones, production of extended-spectrum beta-lactamases, and the increase of multidrug resistant Salmonella strains are major problems in the search for efficient antimicrobial therapy of Salmonella infection.

Artritis séptica por Salmonella no typhi: presentación de un caso y revisión de la bibliografía / Non-typhi Salmonella septic arthritis: case report and review of the literature

La artritis séptica por Salmonella no typhi representa menos del 2 por ciento del total de las artritis sépticas1. El serotipo etiológico más frecuente es Salmonella enteritidis. Su clínica, precedida o no de una gastroenteritis, no difiere de otras artritis sépticas, y se presenta con fiebre y sinovitis monoarticular, habitualmente en rodilla, cadera y hombro. La inmunosupresión (terapéutica, virus de la inmunodeficiencia humana [VIH], lupus eritematoso sistémico [LES], etc.) es el principal factor de riesgo en su desarrollo. La drepanocitosis, la hemofilia, las neoplasias y las edades extremas de la vida también predisponen a su aparición. El diagnóstico se realiza por cultivo de líquido sinovial. El tratamiento está condicionado por las resistencias descritas a múltiples antibióticos, incluso a los más actuales, como son las fluoroquinolonas. Las complicaciones locales más frecuentes son la limitación residual funcional y la osteomielitis. El pronóstico, marcado por la enfermedad de base, presenta una elevada mortalidad (AU)

Elimination of enteric bacteria in biological-chemical wastewater treatment and tertiary filtration units.

The occurrence and removal of salmonellae and faecal indicators in four conventional municipal wastewater treatment plants (MWTP) were investigated. In addition, we tested the efficiency of a semi-technical scale biological nutrient removal process and three pilot-scale tertiary filtration units in microbial removal. All influent samples collected from MWTPs contained salmonellae from 93 to 11,000 MPN/100 ml and indicator bacteria from about 10(7) to 10(8) CFU/100 ml. The reductions in salmonella numbers achieved in full-scale biological-chemical wastewater treatment and semi-technical scale biological nutrient removal processes were usually between 94% and virtually 100% (99.9%) and indicator bacteria reductions between 2 and 3 log units. Microbial numbers in MWTP effluents could be modelled as a function of effluent residual organic matter, suspended solids and total phosphorus concentrations. Pilot-scale tertiary treatment by rapid sand contact filter, chemical contact filter and biological-chemical contact filter reduced salmonella numbers below the detection limit and faecal coliform numbers on average by 99%, 39% and 71%, respectively. A total of 32 Salmonella serovars were identified among 197 Salmonella isolates from municipal wastewaters. Of the isolates, 32% were resistant to nalidixic acid, indicating reduced sensitivity to ciprofloxacin, the drug of choice in the treatment of salmonellosis. In addition, 18% of the isolates were multiresistant. Our results, especially antibiotic resistant Salmonella strains, indicate that conventional municipal wastewater treatment without efficient tertiary treatment, like filtration or disinfection, may constitute a risk for public health.

Stressed salmonella are exposed to reactive oxygen species from two independent sources during recovery in conventional culture media.

Previously, Stephens et al. [J. Appl. Microbiol. 83 (1997) 445-455] developed a sensitive technique for studying the resuscitation of low levels of stressed Salmonella. Using this technique the influence on recovery performance of the peptone component of buffered peptone water was investigated. Within 12 different peptone types as much as 3.5 log10 cells/ml difference was observed between the best and worst performing formulations. Poor recovery performance was linked to reactive oxygen species (ROS) generation through auto-oxidation of reducing sugars and photo-sensitisation of sensitive components such as riboflavin. Supplementary recovery agents were explored with only Oxyrase, which has both enzymes to degrade ROS and the ability to rapidly turn a medium anaerobic, having any significant effect. It improved the speed of recovery and increased, by up to 100-fold, the number of stressed cells recovered. Stressed cells were further studied by flow cytometry with cell sorting, based on the staining pattern from a novel fluorochrome combination, into good and poor recovery media. It was identified that within a stressed population the removal of all oxygen protected actively respiring cells the most by forcing them to generate energy from anaerobic metabolism thus avoiding any risk from accidental endogenous ROS generation. The recognition of two independent sources of oxidative stress in the routine use of conventional culture media is discussed in relation to pathogen detection and other areas of food microbiology.

Norepinephrine stimulates in vitro growth but does not increase pathogenicity of Salmonella choleraesuis in an in vivo model.

Norepinephrine stimulates growth of Escherichia coli, Yersinia enterocolitica, and Pseudomonas aeruginosa in serum-supplemented media, and in vivo increases in norepinephrine may be important in the pathogenesis of sepsis by gram-negative bacteria. Because salmonellosis often is associated with stress, the effects of norepinephrine on in vitro growth, and in vivo pathogenicity of the swine pathogen Salmonella choleraesuis were investigated. When RPMI 1640 with and without pig serum was inoculated with fewer than 100 S. choleraesuis/ml and incubated overnight, bacterial numbers were 10(4) to 10(6) lower in RPMI containing serum. Norepinephrine restored bacterial growth in RPMI with serum to normal levels, but it did not increase growth in serum-free RPMI. Similar results were obtained with SAPI, a nutrient-poor medium previously used to study the effect of norepinephrine on growth of gram-negative bacteria. Conditioned media were produced by growing S. choleraesuis in RPMI containing serum with and without norepinephrine and filter sterilizing. Conditioned medium produced with norepinephrine stimulated growth of S. choleraesuis but not E. coli, whereas conditioned medium produced without norepinephrine stimulated growth of both bacteria. To determine the in vivo effects of norepinephrine, rats were implanted with tablets that secrete norepinephrine for 20 to 24 hours or with identical tablets without norepinephrine and infected intraperitoneally with graded doses of S. choleraesuis. The LD-50 of S. choleraesuis was the same in both groups, and norepinephrine did not affect the carrier rate at 30 days after infection. We concluded that although norepinephrine stimulates in vitro growth of S. choleraesuis in serum-based media, the increase in norepinephrine levels in the present in vivo system was probably not sufficient to influence the pathogenesis of S. choleraesuis infection.

Potential use of live viral and bacterial vectors for vaccines. WHO meeting, Geneva, 19-22 June, 1989.

The use of vaccinia virus vector for the delivery of antigens was first described by Moss and Paoletti and their colleagues in 1982. Such vaccines could be of particular value in developing countries because they would be cheap, stable, easy to administer and provide long-lasting immunity. WHO recognized the potential value of such a delivery system by convening two meetings, one at the National Institutes of Health, USA in November 1984 and the second at WHO headquarters, Geneva, Switzerland in September 1985, to discuss the possibility of using such products, particularly with regard to their safety. Since that time, other vehicles which could be useful for the delivery of antigens have been described. These include Escherichia coli, Salmonella typhimurium, BCG, all other poxviruses, adenovirus, herpesvirus and poliovirus. At its meeting in July 1988, the Scientific Advisory Group of Experts of the Programme for Vaccine Development (SAGE) concluded that it was appropriate to discuss the general topic of live vectors and proceeded to arrange a meeting to discuss the present position and to prepare a report on the following key issues: requirements for safety and efficacy; immunological factors which may influence efficacy; medical constraints on use. The present report results from a meeting held in Geneva from 19 to 22 June 1989.