scholarly journals Lactobacillus rhamnosusGG Suppresses MeningiticE. coliK1 Penetration across Human Intestinal Epithelial Cells In Vitro and Protects Neonatal Rats against Experimental Hematogenous Meningitis

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Sheng-He Huang ◽  
Lina He ◽  
Yanhong Zhou ◽  
Chun-Hua Wu ◽  
Ambrose Jong
Keyword(s):  
Neonatal Sepsis ◽  
Lactobacillus Rhamnosus ◽  
Inhibitory Effect ◽  
Neonatal Rat ◽  
Control Group ◽  
Dependent Manner ◽  
Neonatal Rats ◽  
E Coli

The purpose of this study was to examine prophylactic efficacy of probiotics in neonatal sepsis and meningitis caused byE. coliK1. The potential inhibitory effect ofLactobacillus rhamnosusGG (LGG) on meningiticE. coliK1 infection was examined by using (i) in vitro inhibition assays with E44 (a CSF isolate from a newborn baby withE. colimeningitis), and (ii) the neonatal rat model ofE. colisepsis and meningitis. The in vitro studies demonstrated that LGG blocked E44 adhesion, invasion, and transcytosis in a dose-dependent manner. A significant reduction in the levels of pathogen colonization,E. colibacteremia, and meningitis was observed in the LGG-treated neonatal rats, as assessed by viable cultures, compared to the levels in the control group. In conclusion, probiotic LGG strongly suppresses meningiticE. colipathogens in vitro and in vivo. The results support the use of probiotic strains such as LGG for prophylaxis of neonatal sepsis and meningitis.

scholarly journals Experimental Application of Sage in Rabbit Husbandry

2008 ◽  
Vol 77 (4) ◽  
pp. 581-588 ◽  
Author(s):  
R. Szabóová ◽  
A. Lauková ◽  
Ľ. Chrastinová ◽  
M. Simonová ◽  
V. Strompfová ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Negative Influence ◽  
Feed Consumption ◽  
Control Group ◽  
Coagulase Negative Staphylococci ◽  
E Coli ◽  
Commercial Feed ◽  
Experimental Group

Salvia spp. belongs to the Labiatae family and is characterized by antimicrobial and antiinflammatory effect. The aim of this study was to test its in vitro and in vivo inhibitory effect against bacteria as well as to find an alternative possibility to use sage in the rabbit ecosystem examining biochemical, zootechnical and inmunological indicators, compared to the commercial feed mixture Xtract. Using the sage extract in in vitro tests, its inhibitory effect was noted. Under in vivo conditions, in the experimental group with sage (EG1), reduction of Pseudomonas-like sp. (p < 0.01) and E. coli (p < 0.01) was noted after 7 days of sage application compared to the control group CG2 (with Robenidin) as well as after 21 days of sage extract application, when the reduction of coagulase-negative staphylococci (p < 0.01) was detected (in comparison with the experimental group-EG2, Xtract group). In the caecum of rabbits from EG1, higher values of lactic, acetic and butyric acids were noted. The values of propionic acid were not influenced. Biochemical indicators were not influenced; however, the values of GSH Px were lower in EG1 compared to EG2. Higher phagocytic activity (18%) was noted in EG1 than in EG2 (13%) after 21 days of additives application. The reduction of Eimeria sp. oocysts was demonstrated in EG1 (sage group) after 7 days of sage application comparing to CG2 (217 OPG to 566 OPG). The animals in both experimental groups achieved higher feed consumption and weight gain, lower mortality compared to both controls. Neither of the additives had a negative influence on the health status and growth performance of rabbits.

scholarly journals Effect of Synchronous Versus Sequential Regimens on the Pharmacokinetics and Biodistribution of Regorafenib with Irradiation

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh
Keyword(s):  
Stereotactic Body Radiation Therapy ◽  
In Vivo Studies ◽  
Control Group ◽  
High Dose ◽  
Dependent Manner ◽  
Hep G2 ◽  
Time Curve ◽  
Dose Dependent

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).

Immunomodulatory activities of whey fractions in efferent prefemoral lymph of sheep

1996 ◽  
Vol 63 (2) ◽  
pp. 257-267 ◽  
Author(s):  
Chun W. Wong ◽  
Geoffrey O. Regester ◽  
Geoffrey L. Francis ◽  
Dennis L. Watson
Keyword(s):  
Immune Responses ◽  
Bovine Milk ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Milk Whey ◽  
Significant Difference ◽  
Lymphocyte Phenotypes ◽  
Dose Dependent

SummaryStudies on the immunomodulatory activities of ruminant milk and colostral whey fractions were undertaken. By comparing with boiled colostral whey in a preliminary experiment, a putative heat-labile immunostimulatory factor for antibody responses was found to be present in ovine colostral whey. Studies were then undertaken in sheep in which the efferent prefemoral lymphatic ducts were cannulated bilaterally, and immune responses in the node were measured following subcutaneous injection in the flank fold of whey protein preparations of various purities. A significant sustained decline of efferent lymphocyte output was observed following injection with autologous crude milk whey or colostral whey preparations, but no changes were observed in interferon-gamma levels in lymph plasma. Two bovine milk whey fractions (lactoperoxidase and lactoferrin) of high purity were compared in bilaterally cannulated sheep. A transient decline over the first 6 h was seen in the efferent lymphocyte output and lymph flow rate after injection of both fractions. A significant difference was seen between the two fractions in interferongamma levels in lymph at 6 h after injection. However, no significant changes in the proportion of the various efferent lymphocyte phenotypes were seen following either treatment. Whereas both fractions showed a significant inhibitory effect in a dose-dependent manner on the proliferative response of T lymphocytes, but not B lymphocytes, to mitogenic stimulation in vitro, no similar changes were seen following in vivo stimulation with these two fractions.

Aqueous extracts of avocado pear (Persea americana Mill.) leaves and seeds exhibit anti-cholinesterases and antioxidant activities in vitro

2016 ◽  
Vol 27 (2) ◽  
Author(s):  
Ganiyu Oboh ◽  
Veronica O. Odubanjo ◽  
Fatai Bello ◽  
Ayokunle O. Ademosun ◽  
Sunday I. Oyeleye ◽  
...  
Keyword(s):  
Leaf Extract ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Inhibitory Effect ◽  
Seed Extract ◽  
Persea Americana ◽  
Dependent Manner ◽  
Natural Treatment

AbstractAvocado pear (The inhibitory effects of extracts on AChE and BChE activities and antioxidant potentials (inhibition of FeThe extracts inhibited AChE and BChE activities and prooxidant-induced TBARS production in a dose-dependent manner, with the seed extract having the highest inhibitory effect and the leaf extract exhibiting higher phenolic content and radical scavenging abilities, but lower Fe chelation ability compared with that of the seed. The phytochemical screening revealed the presence of saponins, alkaloids, and terpenoids in both extracts, whereas the total alkaloid profile was higher in the seed extract than in the leaf extract, as revealed by GC-FID.The anti-cholinesterase and antioxidant activities of avocado leaf and seed could be linked to their phytoconstituents and might be the possible mechanisms underlying their use as a cheap and natural treatment/management of AD. However, these extracts should be further investigated in vivo.

scholarly journals Tenovin-6 impairs autophagy by inhibiting autophagic flux

2017 ◽  
Vol 8 (2) ◽  
pp. e2608-e2608 ◽  
Author(s):  
Hongfeng Yuan ◽  
Brandon Tan ◽  
Shou-Jiang Gao
Keyword(s):  
Cell Types ◽  
Inhibitory Effect ◽  
Lymphocytic Leukemia ◽  
Autophagic Flux ◽  
Dependent Manner ◽  
Autophagy Pathway ◽  
Sarcoma Cells ◽  
Regulatory Functions

Abstract Tenovin-6 has attracted significant interest because it activates p53 and inhibits sirtuins. It has anti-neoplastic effects on multiple hematopoietic malignancies and solid tumors in both in vitro and in vivo studies. Tenovin-6 was recently shown to impair the autophagy pathway in chronic lymphocytic leukemia cells and pediatric soft tissue sarcoma cells. However, whether tenovin-6 has a general inhibitory effect on autophagy and whether there is any involvement with SIRT1 and p53, both of which are regulators of the autophagy pathway, remain unclear. In this study, we have demonstrated that tenovin-6 increases microtubule-associated protein 1 light chain 3 (LC3-II) level in diverse cell types in a time- and dose-dependent manner. Mechanistically, the increase of LC3-II by tenovin-6 is caused by inhibition of the classical autophagy pathway via impairing lysosomal function without affecting the fusion between autophagosomes and lysosomes. Furthermore, we have revealed that tenovin-6 activation of p53 is cell type dependent, and tenovin-6 inhibition of autophagy is not dependent on its regulatory functions on p53 and SIRT1. Our results have shown that tenovin-6 is a potent autophagy inhibitor, and raised the precaution in interpreting results where tenovin-6 is used as an inhibitor of SIRT1.

Lactoferrin protects neonatal rats from gut-related systemic infection

2001 ◽  
Vol 281 (5) ◽  
pp. G1140-G1150 ◽  
Author(s):  
Lynn Edde ◽  
Ronaldo B. Hipolito ◽  
Freda F. Y. Hwang ◽  
Denis R. Headon ◽  
Robert A. Shalwitz ◽  
...  
Keyword(s):  
Systemic Infection ◽  
In Vitro Studies ◽  
Peptide Antibiotics ◽  
Neonatal Rats ◽  
Vitro Assay ◽  
E Coli ◽  
Severity Scores ◽  
Factor Α

Lactoferrin is a milk protein that reportedly protects infants from gut-related, systemic infection. Proof for this concept is limited and was addressed during in vivo and in vitro studies. Neonatal rats pretreated orally with recombinant human lactoferrin (rh-LF) had less bacteremia and lower disease severity scores ( P < 0.001) after intestinal infection with Escherichia coli. Control animals had 1,000-fold more colony-forming units of E. coli per milliliter of blood than treated animals ( P < 0.001). Liver cultures from control animals had a twofold increase in bacterial counts compared with cultures from rh-LF-treated pups ( P < 0.02). Oral therapy with rh-LF + FeSO4did not alter the protective effect. In vitro studies confirmed that rh-LF interacted with the infecting bacterium and rat macrophages. An in vitro assay showed that rh-LF did not kill E. coli, but a combination of rh-LF + lysozyme was microbicidal. In vitro studies showed that rat macrophages released escalating amounts of nitric oxide and tumor necrosis factor-α when stimulated with increasing concentrations of rh-LF. The in vitro studies suggest that rh-LF may act with other “natural peptide antibiotics” or may prime macrophages to kill E. coli in vivo.

scholarly journals In vitro inhibitory effect of obtusofolin on the activity of CYP3A4, 2C9, and 2E1

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Na Liu ◽  
Ping Chen ◽  
Xiaojun Du ◽  
Junxia Sun ◽  
Shasha Han
Keyword(s):  
Human Liver ◽  
Competitive Inhibition ◽  
Liver Microsomes ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Cytochrome P450 Enzymes ◽  
Inhibition Model ◽  
Dose Dependent

Abstract Background Obtusofolin is the major active ingredient of Catsia tora L., which possesses the activity of improving eyesight and protecting the optic nerve. Investigation on the interaction of obtusofolin with cytochrome P450 enzymes (CYP450s) could provide a reference for the clinical application of obtusofolin. Methods The effect of obtusofolin on the activity of CYP450s was investigated in the presence of 100 μM obtusofolin in pooled human liver microsomes (HLMs) and fitted with the Lineweaver–Burk plots to characterize the specific inhibition model and kinetic parameters. Results Obtusofolin was found to significantly inhibited the activity of CYP3A4, 2C9, and 2E1. In the presence of 0, 2.5, 5, 10, 25, 50, and 100 μM obtusofolin, the inhibition of these CYP450s showed a dose-dependent manner with the IC50 values of 17.1 ± 0.25, 10.8 ± 0.13, and 15.5 ± 0.16 μM, respectively. The inhibition of CYP3A4 was best fitted with the non-competitive inhibition model with the Ki value of 8.82 μM. While the inhibition of CYP2C9 and 2E1 was competitive with the Ki values of 5.54 and 7.79 μM, respectively. After incubating for 0, 5, 10, 15, and 30 min, the inhibition of CYP3A4 was revealed to be time-dependent with the KI value of 4.87 μM− 1 and the Kinact value of 0.0515 min− 1. Conclusions The in vitro inhibitory effect of obtusofolin implying the potential drug-drug interaction between obtusofolin and corresponding substrates, which needs further in vivo validations.

scholarly journals Development and Optimization of a Neonatal Rat Model of Sepsis

2018 ◽  
Vol 3 (1) ◽  
Keyword(s):  
Blood Culture ◽  
Rat Model ◽  
Neonatal Sepsis ◽  
Neonatal Rat ◽  
Neonatal Rats ◽  
Minimum Effective Dose ◽  
Biochemical Tests ◽  
E Coli ◽  
Common Causes ◽  
Neonatal Rat Model

Neonatal sepsis is the most common cause of mortality in newborns. Currently antibiotics and supportive care are the mainstay of treatment. Blood culture is considered as the gold standard for confirmation of diagnosis of neonatal sepsis. Here we have tried to develop a neonatal rat model of sepsis in order to better understand its progression. Lipopolysaccharide (LPS) is one of the common agents used to induce sepsis in rats. Here we found that LPS was ineffective in inducing sepsis in neonatal rats. We found that induction of live dose of Escherichia coli, one of the most common causes of neonatal sepsis was more effective than LPS injection. The rats were continuously monitored for the visual indications of sepsis development. Body weight, body temperature and the activity of rats were monitored continuously. Blood culture was done to check for the confirmation of diagnosis of sepsis. Further biochemical tests such as citrate, urease, indole and kliger-ion tests were done to confirm for E coli in the colonies of blood culture. The minimum effective dose of E coli needed to induce sepsis in neonatal rats was found to be 5*106 CFU of E coli.

IMB-BZ as an Inhibitor Targeting ESX-1 Secretion System to Control Mycobacterial Infection

2021 ◽  
Author(s):  
Pingping Jia ◽  
Yi Zhang ◽  
Jian Xu ◽  
Mei Zhu ◽  
Shize Peng ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Mycobacterial Infection ◽  
Underlying Mechanism ◽  
Inhibitory Effect ◽  
New Drugs ◽  
Dependent Manner ◽  
High Potency ◽  
Resistance Development

Abstract Background Resistance to anti-tuberculosis (TB) drug is a major issue in TB control, and demands the discovery of new drugs targeting virulence factor ESX-1. Methods We first established a high-throughput screen (HTS) assay for the discovery of ESX-1 secretion inhibitors. The positive hits were then evaluated for the potency of diminishing the survival of virulent mycobacterium and reducing bacterial virulence. We further investigated the probability of inducing drug-resistance and the underlying mechanism using M-PFC. Results A robust HTS assay was developed to identify small molecules that inhibit ESX-1 secretion without impairing bacterial growth in vitro. A hit named IMB-BZ specifically inhibits the secretion of CFP-10 and reduces virulence in an ESX-1-dependent manner, therefore resulting in significant reduction in intracellular and in vivo survival of mycobacteria. Blocking the CFP-10-EccCb1 interaction directly or indirectly underlies the inhibitory effect of IMB-BZ on the secretion of CFP-10. Importantly, our finding shows that the ESX-1 inhibitors pose low risk of drug resistance development by mycobacteria in vitro as compared with traditional anti-TB drug, and exhibit high potency against chronic mycobacterial infection. Conclusion Targeting ESX-1 may lead to the development of novel therapeutics for tuberculosis. IMB-BZ holds the potential for future development into a new anti-TB drug.

scholarly journals Sevoflurane Promotes Bactericidal Properties of Macrophages through Enhanced Inducible Nitric Oxide Synthase Expression in Male Mice

2019 ◽  
Vol 131 (6) ◽  
pp. 1301-1315 ◽  
Author(s):  
Thomas J. Gerber ◽  
Valérie C. O. Fehr ◽  
Suellen D. S. Oliveira ◽  
Guochang Hu ◽  
Randal Dull ◽  
...  
Keyword(s):  
Early Stage ◽  
No Synthase ◽  
Control Group ◽  
Male Mice ◽  
Proinflammatory Response ◽  
E Coli ◽  
Inducible No Synthase ◽  
Bactericidal Properties

Abstract Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Sevoflurane with its antiinflammatory properties has shown to decrease mortality in animal models of sepsis. However, the underlying mechanism of its beneficial effect in this inflammatory scenario remains poorly understood. Macrophages play an important role in the early stage of sepsis as they are tasked with eliminating invading microbes and also attracting other immune cells by the release of proinflammatory cytokines such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Thus, the authors hypothesized that sevoflurane mitigates the proinflammatory response of macrophages, while maintaining their bactericidal properties. Methods Murine bone marrow–derived macrophages were stimulated in vitro with lipopolysaccharide in the presence and absence of 2% sevoflurane. Expression of cytokines and inducible NO synthase as well as uptake of fluorescently labeled Escherichia coli (E. coli) were measured. The in vivo endotoxemia model consisted of an intraperitoneal lipopolysaccharide injection after anesthesia with either ketamine and xylazine or 4% sevoflurane. Male mice (n = 6 per group) were observed for a total of 20 h. During the last 30 min fluorescently labeled E. coli were intraperitoneally injected. Peritoneal cells were extracted by peritoneal lavage and inducible NO synthase expression as well as E. coli uptake by peritoneal macrophages was determined using flow cytometry. Results In vitro, sevoflurane enhanced lipopolysaccharide-induced inducible NO synthase expression after 8 h by 466% and increased macrophage uptake of fluorescently labeled E. coli by 70% compared with vehicle-treated controls. Inhibiting inducible NO synthase expression pharmacologically abolished this increase in bacteria uptake. In vivo, inducible NO synthase expression was increased by 669% and phagocytosis of E. coli by 49% compared with the control group. Conclusions Sevoflurane enhances phagocytosis of bacteria by lipopolysaccharide-challenged macrophages in vitro and in vivo via an inducible NO synthase–dependent mechanism. Thus, sevoflurane potentiates bactericidal and antiinflammatory host-defense mechanisms in endotoxemia.

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