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Microorganisms develop biofilms on indwelling medical devices and are associated with biofilm-related infections, resulting in substantial morbidity and mortality. Therefore, to prevent and control biofilm-associated infections, the present study was designed to assess the anti-biofilm potential of postbiotics derived from probiotic organisms against most prevalent biofilm-forming Pseudomonas aeruginosa PAO1. Eighty lactic acid bacteria isolated from eight neonatal fecal samples possessed antibacterial activity against P. aeruginosa PAO1. Among these, only four lactic acid bacteria produced both bacteriocin and exopolysaccharides but only one isolate was found to maximally attenuate the P. aeruginosa PAO1 biofilm. More specifically, the phenotypic and probiotic characterization showed that the isolated lactic acid bacteria were gram positive, non-motile, and catalase and oxidase negative; tolerated acidic and alkaline pH; has bile salt concentration; showed 53% hydrophobicity; and was found to be non-hemolytic. Phylogenetically, the organism was found to be probiotic Lactobacillus fermentum with accession no. KT998657. Interestingly, pre-coating of a microtiter plate either with bacteriocin or with exopolysaccharides as well as their combination significantly (p < 0.05) reduced the number of viable cells forming biofilms to 41.7% compared with simultaneous coating of postbiotics that had 72.4% biofilm-forming viable cells as observed by flow cytometry and confocal laser scanning microscopy. Therefore, it can be anticipated that postbiotics as the natural biointerventions can be employed as the prophylactic agents for medical devices used to treat gastrointestinal and urinary tract infections. [ABSTRACT FROM AUTHOR]

Diet makes an important contribution to colorectal cancer (CRC) risk implying risks for CRC are potentially reducible. Therefore, the probiotics have been suggested as the prophylactic measure in colon cancer. In this study, different probiotics were used to compare their protective potential against 1,2 dimethylhydrazine dihydrochloride (DMH)-induced chemical colon carcinogenesis in Sprague Dawley rats. Animals belonging to different probiotic groups were fed orally with 1 × 109lactobacilli daily for 1 week, and then a weekly injection of DMH was given intraperitoneally for 6 wks with daily administration of probiotic.Lactobacillus GGandL.acidophilus+ DMH-treated animals had maximum percent reduction in ACF counts. A significant decrease (P< 0.05) in fecal nitroreductase activity was observed inL.casei+ DMH andL.plantarum+ DMH-treated rats whereas β-glucuronidase activity decreased inL.GG+ DMH andL.acidophilus+ DMH-treated rats. Animals treated withBifidobacterium bifidum+ DMH had significant decreased β-glucosidase activity. However, not much difference was observed in the colon morphology of animals belonging to various probiotic + DMH-treated rats compared with DMH-treated alone. The results indicated that probiotics,L.GG, andL.acidophiluscan be used as the better prophylactic agents for experimental colon carcinogenesis. [ABSTRACT FROM PUBLISHER]

Giardiasis is one of the major contributors of diarrheal cases globally with a higher prevalence rate amongst children. Over the past few years, the widespread use of drugs has lead to an emergence of drug resistance in Giardia lamblia. Thus, a major shift has been witnessed in search of natural biocompatible substances that could effectively counteract the problem. Terefore, the present study was aimed to evaluate the protective effect of Lactobacillus casei in murine giardiasis. The protective efficacy of L. casei was monitored in BALB/c mice infected with Giardia trophozoites. Experimentally, it was observed that oral administration of probiotic both prior and simultaneously with Giardia trophozoites reduced the severity of Giardia infection. Interestingly, transmission electron microscopy clearly showed the rapid restoration of gut atrophy as well as adherent lactobacilli to the intestinal epithelial cells in probiotic treated mice compare to Giardia infected mice. Moreover, nitrite levels decreased and anti Giardia serum IgG levels increased significantly in probiotic treated mice after peak infection. Thus, the data supports the protective effect of L. casei that can limit the jejunum brush border atrophy by alleviating the immune response and can be usqful as an oral adjuvant. [ABSTRACT FROM AUTHOR]

The study describes the in vivo activity of Lactobacillus casei in malnourished Giardia lamblia-infected BALB/c mice. By experimentation, it was found that daily administration of the probiotic 7 days before inoculation with Giardia trophozoites in malnourished mice efficiently reduced both the severity and duration of giardiasis. More specifically, excretion of Giardia cysts and trophozoites counts were reduced, while faecal lactobacilli counts increased significantly in probiotic-fed malnourished mice, compared with control mice. Interestingly, it was also observed that oral feeding of the probiotic to malnourished mice abrogated all the anthropometric and biochemical anomalies. Histologically, morphological and cellular alteration of microvillus membrane integrity revealed that probiotic administration ameliorated the mucosal damage in malnourished, probiotic-inoculated, Giardia-infected mice compared with the severe microvillus atrophy, œdematous and vacuolated epithelial cells, and ileitis in malnourished Giardia-infected mice. The results clearly show the antigiardial effect of the probiotic in vivo by modulating the gut cells to inhibit the colonization and multiplication of Giardia trophozoites, thus reducing the severity and duration of murine giardiasis. Cette étude décrit l'activité de Lactobacillus casei in vivo chez des souris BALB/c malnutries et infectées par Giardia lamblia. Expérimentalement, l'administration quotidienne de probiotiques 7 jours avant l'inoculation de trophozoïtes de Giardia aux souris malnutries des réduisait efficacement tant la sévérité que la durée de la lambliase. Plus spécifiquement, l'excrétion de kystes de Giardia et la numération de trophozoïtes étaient réduites alors que les comptes de lactobacilles fécales augmentaient significativement chez les souris malnutries ayant reçu des probiotiques, comparativement aux souris contrôles. Fait intéressant, l'administration orale de probiotiques chez les souris malnutries annulait toutes les anomalies morphologiques et biochimiques. Histologiquement, la modification morphologique et cellulaire de l'intégrité de la membrane des microvillosités a révélé que l'administration de probiotiques atténuait les dommages causées par Giardia aux muqueuses des souris malnutries, alors que les souris malnutries et infectées n'ayant pas reçu de probiotiques présentaient une atrophie sévère des microvillosités, des cellules épithéliales oedémateuses et vaculolées ainsi que des signes d'iléite. Ces résultats démontrent clairement l'effet anti-lambliase des probiotiques in vivo, par la modulation de la capacité des cellules de l'intestin à inhiber la colonisation et la multiplication des trophozoïtes de Giardia, réduisant ainsi la sévérité et la durée de la lambliase chez la souris. [ABSTRACT FROM AUTHOR]

The gut microflora is an important constituent in the intestinal mucosal barrier and has been introduced as the concept of probiotic therapy that beneficially affects the host by improving its intestinal microbial balance. Therefore, the main objective of the study was to explore the protective potential of various lactobacilli strains for murine giardiasis. By experimentation, it was found that the probiotic supplementation of either Lactobacillus casei, L. acidophilus, L. plantarum, or L. rhamnosus GG, 7 days prior to inoculation with G. lamblia trophozoites, reduced the rate of cyst excretion compared with Giardia-infected mice. Interestingly, L. GG was found to be the most effective probiotic in reducing the duration of giardia cycle and acts as an effective prophylactic probiotic for murine giardiasis but needs to be clinically correlated due to entirely different human microflora. [ABSTRACT FROM AUTHOR]

This study describes the in vivo activity of Lactobacillus acidophilus in Giardia lamblia infected BALB/c mice. Experimentally, it was observed that daily administration of lactobacilli 7 days before or in simultaneous inoculation with Giardia trophozoites efficiently reduced G. lamblia infection in mice. More specifically, excretion of Giardia cysts were reduced significantly in probiotic-treated groups, and resolution of infection was observed by day 21 post-inoculation. It was also observed that the lactobacillus count increased tremendously and continuously in faeces of all probiotic-fed mice, and was significantly higher as compared with that in control mice. Histological analysis of microvilli membrane integrity revealed that probiotic administration also protected mice against parasite-induced mucosal damage, whereas Giardia-infected mice had severe villous atrophy, oedema, vacuolation and ileitis. Immunologically, the anti- Giardia serum IgG level was not stimulated significantly by probiotic treatment administered both prior to and simultaneous with Giardia infection, but remained high after the infection peak. Taken together, the data demonstrates the anti-giardial effect of the probiotic in vivo by modulation of the intestinal epithelial cells, inhibiting the colonization of Giardia trophozoites and thereby reducing the severity of Giardia infection. [ABSTRACT FROM AUTHOR]

The present study aimed to improve solubility, dissolution and ultimate bioavailability of poorly soluble artemether, an antimalarial drug, by encapsulating it in β-cyclodextrin (β-CD) and its methyl and hydroxylpropyl derivatives. The effect of these complexes was confirmed by in vivo studies. Phase solubility studies indicated 1:1 stoichiometry and were supported by mass spectrometry and proton nuclear magnetic resonance (¹H-NMR) spectroscopy. True inclusion of artemether into the cyclodextrin cavity was observed in lyophilized complexes by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FT-IR) studies. The mode of inclusion was supported by two-dimensional (2D) NMR. Solution calorimetry was used to confirm 1:1 stiochiometry by determining the enthalpy of interaction between the drug and cyclodextrins. The stability constant (K) of inclusion and other thermodynamic parameters such as enthalpy (ΔH) as well as entropy (ΔS) of binding accompanying the encapsulation were determined. The calculated value of K indicated that M-β-CD has maximum complexing efficiency. Dissolution studies indicated that the highest release rate was observed for lyophilized complexes. In vivo studies of lyophilized complexes of M-β-CD showed a 3-fold increase in antimalarial activity compared to artemether and resulted in 100% eradication of parasite. However, 83% and 50% survival rates were achieved in 40 days using HP-β-CD and β-CD complexes respectively. The study concludes that encapsulation of artemether by cyclodextrins is a good alternative to enhance the bioavailability of the drug. [ABSTRACT FROM AUTHOR]

Microorganisms develop biofilms on indwelling medical devices and are associated with biofilm-related infections, resulting in substantial morbidity and mortality. Therefore, to prevent and control biofilm-associated infections, the present study was designed to assess the anti-biofilm potential of postbiotics derived from probiotic organisms against most prevalent biofilm-forming Pseudomonas aeruginosa PAO1. Eighty lactic acid bacteria isolated from eight neonatal fecal samples possessed antibacterial activity against P. aeruginosa PAO1. Among these, only four lactic acid bacteria produced both bacteriocin and exopolysaccharides but only one isolate was found to maximally attenuate the P. aeruginosa PAO1 biofilm. More specifically, the phenotypic and probiotic characterization showed that the isolated lactic acid bacteria were gram positive, non-motile, and catalase and oxidase negative; tolerated acidic and alkaline pH; has bile salt concentration; showed 53% hydrophobicity; and was found to be non-hemolytic. Phylogenetically, the organism was found to be probiotic Lactobacillus fermentum with accession no. KT998657. Interestingly, pre-coating of a microtiter plate either with bacteriocin or with exopolysaccharides as well as their combination significantly (p < 0.05) reduced the number of viable cells forming biofilms to 41.7% compared with simultaneous coating of postbiotics that had 72.4% biofilm-forming viable cells as observed by flow cytometry and confocal laser scanning microscopy. Therefore, it can be anticipated that postbiotics as the natural biointerventions can be employed as the prophylactic agents for medical devices used to treat gastrointestinal and urinary tract infections.

Background: Food borne infections caused by Salmonella enterica species are increasing globally and pregnancy poses a significant threat in developing countries, where sanitation facilities are inadequate. Thus, the present study was designed to delineate the effect of Salmonella infection during pregnancy., Method: Pregnant, BALB/c mice were challenged orally with Salmonella enterica serovar Typhimurium on gestational day 10 and were monitored for bacterial load, hepatic injury, histopathological alterations vis-a-vis oxidant and antioxidant levels., Results: Pregnant- Salmonella -infected mice had higher bacterial translocation in the liver, spleen as well as liver enzymes mainly aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase compared with Salmonella- infected mice. The levels of lipid peroxidation were significantly higher in all the organs of both pregnant- Salmonella- infected and Salmonella -infected mice compared with control mice. However, the activities of antioxidant enzymes (reduced glutathione, superoxide dismutase and catalase) were lower in the liver, spleen and placenta of pregnant, pregnant- Salmonella -infected and Salmonella- infected mice compared with control mice, but the decrease was more in pregnant- Salmonella -infected mice indicating depression of antioxidant defense system. Histopathologically, pregnant- Salmonella -infected mice had more architectural damage in the liver, spleen and placenta compared with other groups., Conclusion: Pregnancy makes the host more vulnerable to typhoid fever by affecting the physiology of pivotal organs and highlighting the importance of early and prompts diagnosis so as to avoid the further materno-fetal complications.

Malaria leads to pathophysiological and biochemical alterations in placenta and blood of pregnant mice. A significant decrease in the sugar, protein and lipid levels in the placental homogenate of pregnant-infected mice was observed compared to the pregnant mice. However, serum protein content was not altered much in the pregnant-infected mice as compared to the levels in control mice. The serum lipid level enhanced significantly in both pregnant and non pregnant-infected mice. The enzymatic activities of alkaline phosphatase and acid phosphatase altered significantly in malaria-infected placenta. Our study clearly highlights the possible role of these enzymes in damaging the placenta which in turn may jeoparadise the fetal growth together with altered biochemistry of placenta. Therefore biochemical along with pathological alterations occurring during malaria infection in pregnancy may account for compromised maternal fetal relationship.