scholarly journals Concanavalin A Protects Mice from a Lethal Inoculation of Intragastric Klebsiella pneumoniae and Reduces the Induced Liver Damage

2007 ◽  
Vol 51 (9) ◽  
pp. 3122-3130 ◽  
Author(s):  
Chih-Feng Kuo ◽  
Ya-Hui Wang ◽  
Huan-Yao Lei ◽  
Chiou-Huey Wang ◽  
Nina Tsao
Keyword(s):  
Klebsiella Pneumoniae ◽  
Concanavalin A ◽  
Blood Levels ◽  
Dependent Manner ◽  
Vitro Assay ◽  
Invasive Diseases ◽  
Dose Dependent ◽  
Liver Infection ◽  
Liver Tissues

ABSTRACT Intragastric inoculation of Klebsiella pneumoniae can cause invasive diseases, including necrosis of liver tissues and bacteremia. The effect of concanavalin A (ConA) on K. pneumoniae was tested. Pretreatment with ConA was able to protect mice from K. pneumoniae infection in an intragastric model. K. pneumoniae-induced mouse death and liver injury such as liver necrosis, as well as blood levels of aspartate aminotransferase and alanine aminotransferase, were inhibited in a dose-dependent manner by ConA. ConA administered intravenously as late as 24 h after K. pneumoniae inoculation was still protective. In an in vitro assay, ConA was able to bind K. pneumoniae cells directly and further agglutinate them but had no effect on their in vitro growth. Surveys of bacterial counts of ConA-treated mice revealed that the bacteria were eliminated effectively in both blood and liver tissues. Furthermore, the bactericidal activity of macrophages against K. pneumoniae was also enhanced in a dose-dependent manner by ConA in an in vitro culture. These data suggest that ConA is a potentially therapeutic agent for K. pneumoniae-induced liver infection.

scholarly journals Protection against Klebsiella pneumoniae Using Lithium Chloride in an Intragastric Infection Model

2014 ◽  
Vol 59 (3) ◽  
pp. 1525-1533 ◽  
Author(s):  
Nina Tsao ◽  
Chih-Feng Kuo ◽  
Ching-Chen Chiu ◽  
Wei-Chen Lin ◽  
Wan-Hui Huang ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Lithium Chloride ◽  
Blood Levels ◽  
Infection Model ◽  
Dependent Manner ◽  
Toxic Dose ◽  
Content Type ◽  
Bipolar Mood Disorder ◽  
Liver Tissues

ABSTRACTIntragastricKlebsiella pneumoniaeinfections of mice can cause liver abscesses, necrosis of liver tissues, and bacteremia. Lithium chloride, a widely prescribed drug for bipolar mood disorder, has been reported to possess anti-inflammatory properties. Using an intragastric infection model, the effects of LiCl onK. pneumoniaeinfections were examined. Providing mice with drinking water containing LiCl immediately after infection protected them fromK. pneumoniae-induced death and liver injuries, such as necrosis of liver tissues, as well as increasing blood levels of aspartate aminotransferase and alanine aminotransferase, in a dose-dependent manner. LiCl administered as late as 24 h postinfection still provided protection. Monitoring of the LiCl concentrations in the sera ofK. pneumoniae-infected mice showed that approximately 0.33 mM LiCl was the most effective dose for protecting mice against infections, which is lower than the clinically toxic dose of LiCl. Surveys of bacterial counts and cytokine expression levels in LiCl-treated mice revealed that both were effectively inhibited in blood and liver tissues. Usingin vitroassays, we found that LiCl (5 μM to 1 mM) did not directly interfere with the growth ofK. pneumoniaebut madeK. pneumoniaecells lose the mucoid phenotype and become more susceptible to macrophage killing. Furthermore, low doses of LiCl also partially enhanced the bactericidal activity of macrophages. Taken together, these data suggest that LiCl is an alternative therapeutic agent forK. pneumoniae-induced liver infections.

scholarly journals Experimental Phage Therapy in TreatingKlebsiella pneumoniae-Mediated Liver Abscesses and Bacteremia in Mice

2011 ◽  
Vol 55 (4) ◽  
pp. 1358-1365 ◽  
Author(s):  
Chih-Hsin Hung ◽  
Chih-Feng Kuo ◽  
Chiou-Huey Wang ◽  
Ching-Ming Wu ◽  
Nina Tsao
Keyword(s):  
Low Dose ◽  
Therapeutic Agent ◽  
Blood Levels ◽  
Intragastric Administration ◽  
Dependent Manner ◽  
Inflammatory Cytokine Production ◽  
Liver Abscesses ◽  
Intraperitoneal Treatment ◽  
Dose Dependent ◽  
Liver Infection

ABSTRACTIntragastric inoculation of mice withKlebsiella pneumoniaecan cause liver abscesses, necrosis of liver tissues, and bacteremia. A newly isolated phage (φNK5) with lytic activity forK. pneumoniaewas used to treatK. pneumoniaeinfection in an intragastric model. Both intraperitoneal and intragastric administration of a single dose of φNK5 lower than 2 × 108PFU at 30 min afterK. pneumoniaeinfection was able to protect mice from death in a dose-dependent manner, but the efficacy achieved with a low dose of φNK5 by intragastric treatment provided the more significant protection. Phage φNK5 administered as late as 24 h afterK. pneumoniaeinoculation was still protective, while intraperitoneal treatment with phage was more efficient than intragastric treatment as a result of the dissemination of bacteria into the circulation at 24 h postinfection. Surveys of bacterial counts for mice treated with φNK5 by the intraperitoneal route revealed that the bacteria were eliminated effectively from both blood and liver tissue.K. pneumoniae-induced liver injury, such as liver necrosis, as well as blood levels of aspartate aminotransferase and alanine aminotransferase and inflammatory cytokine production, was significantly inhibited by φNK5 treatment. These data suggest that a low dose of φNK5 is a potential therapeutic agent forK. pneumoniae-induced liver infection.

scholarly journals A New Immunosuppressive Pregnane Glycoside and Two Known Analogues from Epigynum cochinchinensis

2018 ◽  
Vol 13 (6) ◽  
pp. 1934578X1801300
Author(s):  
Yuting Shao ◽  
Yan Zhao ◽  
Hong Zhang ◽  
Mengjun Jiang ◽  
Afsar Khan ◽  
...  
Keyword(s):  
Concanavalin A ◽  
Soluble Fraction ◽  
Spectroscopic Techniques ◽  
Dependent Manner ◽  
Immunosuppressive Activity ◽  
Con A ◽  
Phytochemical Investigation ◽  
Pregnane Glycoside ◽  
Dose Dependent

Phytochemical investigation of the ethyl acetate soluble fraction from the leaves of Epigynum cochinchinensis led to the isolation of one new C21 pregnane glycoside, epigycoside C (1), along with two known analogues epigycoside A (2) and epigynoside G (3). Their structures were elucidated on the basis of extensive spectroscopic techniques. The in vitro immunosuppressive activity of compound 1 was evaluated against concanavalin A (Con A)- and lipopolysaccharides (LPS)-stimulated proliferation of mice splenocytes. Compound 1 displayed significant immunosuppressive activities in a dose-dependent manner.

Erythropoietin regulates endothelial progenitor cells

Blood ◽  
2004 ◽  
Vol 103 (3) ◽  
pp. 921-926 ◽  
Author(s):  
Ferdinand H. Bahlmann ◽  
Kirsten de Groot ◽  
Jens-Michael Spandau ◽  
Aimee L. Landry ◽  
Barbara Hertel ◽  
...  
Keyword(s):  
Progenitor Cells ◽  
Endothelial Progenitor Cells ◽  
Peripheral Blood ◽  
Healthy Subjects ◽  
Tube Formation ◽  
Dependent Manner ◽  
Endothelial Progenitor ◽  
Vitro Assay ◽  
Dose Dependent

AbstractCirculating bone marrow–derived endothelial progenitor cells (EPCs) promote vascular reparative processes and neoangiogenesis, and their number in peripheral blood correlates with endothelial function and cardiovascular risk. We tested the hypothesis that the cytokine erythropoietin (EPO) stimulates EPCs in humans. We studied 11 patients with renal anemia and 4 healthy subjects who received standard doses of recombinant human EPO (rhEPO). Treatment with rhEPO caused a significant mobilization of CD34+/CD45+ circulating progenitor cells in peripheral blood (measured by flow cytometry), and increased the number of functionally active EPCs (measured by in vitro assay) in patients (week 2, 312% ± 31%; week 8, 308% ± 40%; both P < .01 versus baseline) as well as in healthy subjects (week 8, 194% ± 15%; P < .05 versus baseline). The effect on EPCs was already observed with an rhEPO dose of about 30 IU/kg per week. Administration of rhEPO increased the number of functionally active EPCs by differentiation in vitro in a dose-dependent manner, assessed in cell culture and by tube formation assay. Furthermore, rhEPO activates the Akt protein kinase pathway in EPCs. Erythropoietin increases the number of functionally active EPCs in humans. Administration of rhEPO or EPO analogs may open new therapeutic strategies in regenerative cardiovascular medicine.

scholarly journals Evaluation of Anti-Mycobacterial Compounds in a Silkworm Infection Model with Mycobacteroides abscessus

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4971
Author(s):  
Kanji Hosoda ◽  
Nobuhiro Koyama ◽  
Hiroshi Hamamoto ◽  
Akiho Yagi ◽  
Ryuji Uchida ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
In Vitro Assay ◽  
Infection Model ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Vitro Assay ◽  
Infection Assay ◽  
Microbial Products ◽  
Dose Dependent

Among four mycobacteria, Mycobacterium avium, M. intracellulare, M. bovis BCG and Mycobacteroides (My.) abscessus, we established a silkworm infection assay with My. abscessus. When silkworms (fifth-instar larvae, n = 5) were infected through the hemolymph with My. abscessus (7.5 × 107 CFU/larva) and bred at 37 °C, they all died around 40 h after injection. Under the conditions, clarithromycin and amikacin, clinically used antimicrobial agents, exhibited therapeutic effects in a dose-dependent manner. Furthermore, five kinds of microbial compounds, lariatin A, nosiheptide, ohmyungsamycins A and B, quinomycin and steffimycin, screened in an in vitro assay to observe anti-My. abscessus activity from 400 microbial products were evaluated in this silkworm infection assay. Lariatin A and nosiheptide exhibited therapeutic efficacy. The silkworm infection model with My. abscessus is useful to screen for therapeutically effective anti-My. abscessus antibiotics.

Oxygenation of 18-hydroxycorticosterone as the final reaction for aldosterone biosynthesis

1984 ◽  
Vol 107 (3) ◽  
pp. 395-400 ◽  
Author(s):  
Itaru Kojima ◽  
Etsuro Ogata ◽  
Hiroshi Inano ◽  
Bun-ichi Tamaoki
Keyword(s):  
Carbon Monoxide ◽  
Hydroxysteroid Dehydrogenase ◽  
Dependent Manner ◽  
In Vitro Production ◽  
Mitochondrial Preparation ◽  
Final Reaction ◽  
Vitro Production ◽  
Dose Dependent ◽  
Cytochrome P 450

Abstract. Incubation of 18-hydroxycorticosterone with the sonicated mitochondrial preparation of bovine adrenal glomerulosa tissue leads to the production of aldosterone, as measured by radioimmunoassay. The in vitro production of aldosterone from 18-hydroxycorticosterone requires both molecular oxygen and NADPH, and is inhibited by carbon monoxide. Cytochrome P-450 inhibitors such as metyrapone, SU 8000. SU 10603, SKF 525A, amphenone B and spironolactone decrease the biosynthesis of aldosterone from 18-hydroxycorticosterone. These results support the conclusion that the final reaction in aldosterone synthesis from 18-hydroxycorticosterone is catalyzed by an oxygenase, but not by 18-hydroxysteroid dehydrogenase. By the same preparation, the production of [3H]aldosterone but not [3H]18-hydroxycorticosterone from [1,2-3H ]corticosterone is decreased in a dose-dependent manner by addition of non-radioactive 18-hydroxycorticosterone.

Appraisal of Immunological Impacts of Melaleuca leucadendra Extract over Macrophage Performance in Vitro

2020 ◽  
Keyword(s):  
Nitric Oxide ◽  
Interleukin 2 ◽  
Dependent Manner ◽  
Reduced Pressure ◽  
Medical Plant ◽  
Dose Dependent ◽  
Level Production ◽  
Melaleuca Leucadendra ◽  
Phagocytic Killing

This trial research was performed to discuss the immune-influence of Melaleuca leucadendra ‘paper-bark tree’ dried leaves which is an important medical plant known in many regions in the world. The leaves were dissolved in a mixture of (ethanol + water) (3:1) mixture, then filtered, evaporated and dried under reduced pressure to obtain leaves extract. The macrophages of blood derived origin were provided from rats and mixed with three different leaves extracts doses in tissue culture plates and incubated then stained with fluorescent acridine orange and examined under fluorescent microscope to assess the phagocytic and killing potency. The wells contents were aspirated and assayed for nitric oxide and interleukin-2 levels. The results displayed an obvious increase in phagocytic, killing performance as well as nitric oxide and IL-2 level production than control in a dose dependent manner. The obtained results suggested the immune-stimulant impact of the paper-bark tree leaves.

Serotonin elicits long-lasting enhancement of rhythmic respiratory activity in turtle brain stems in vitro

2001 ◽  
Vol 91 (6) ◽  
pp. 2703-2712 ◽  
Author(s):  
Stephen M. Johnson ◽  
Julia E. R. Wilkerson ◽  
Daniel R. Henderson ◽  
Michael R. Wenninger ◽  
Gordon S. Mitchell
Keyword(s):  
Brain Stem ◽  
Respiratory Activity ◽  
Dependent Manner ◽  
Frequency Increase ◽  
Burst Frequency ◽  
Bath Application ◽  
Burst Amplitude ◽  
Dose Dependent ◽  
The Brain

Brain stem preparations from adult turtles were used to determine how bath-applied serotonin (5-HT) alters respiration-related hypoglossal activity in a mature vertebrate. 5-HT (5–20 μM) reversibly decreased integrated burst amplitude by ∼45% ( P < 0.05); burst frequency decreased in a dose-dependent manner with 20 μM abolishing bursts in 9 of 13 preparations ( P < 0.05). These 5-HT-dependent effects were mimicked by application of a 5-HT1A agonist, but not a 5-HT1B agonist, and were abolished by the broad-spectrum 5-HT antagonist, methiothepin. During 5-HT (20 μM) washout, frequency rebounded to levels above the original baseline for 40 min ( P < 0.05) and remained above baseline for 2 h. A 5-HT3 antagonist (tropesitron) blocked the post-5-HT rebound and persistent frequency increase. A 5-HT3 agonist (phenylbiguanide) increased frequency during and after bath application ( P < 0.05). When phenylbiguanide was applied to the brain stem of brain stem/spinal cord preparations, there was a persistent frequency increase ( P < 0.05), but neither spinal-expiratory nor -inspiratory burst amplitude were altered. The 5-HT3receptor-dependent persistent frequency increase represents a unique model of plasticity in vertebrate rhythm generation.

Changes in growth rate and thyroid- and sex-hormones blood levels in rats under sub-chronic lithium treatment

2006 ◽  
Vol 25 (5) ◽  
pp. 243-250 ◽  
Author(s):  
M S Allagui ◽  
N Hfaiedh ◽  
C Vincent ◽  
F Guermazi ◽  
J-C Murat ◽  
...  
Keyword(s):  
Growth Rate ◽  
Lithium Treatment ◽  
Lithium Carbonate ◽  
Serum Levels ◽  
Antagonistic Effect ◽  
Blood Levels ◽  
Vaginal Mucosa ◽  
Dependent Manner ◽  
Serum Concentrations ◽  
Dose Dependent

Lithium therapy, mainly used in curing some psychiatric diseases, is responsible for numerous undesirable side effects. The present study is a contribution to the understanding of the pathophysiological mechanisms underlying lithium toxicity. Male and female mature rats were divided into three batches and fed commercial pellets: one batch was the control and the second and third batches were given 2 g (Li1) and 4 g (Li2) of lithium carbonate/kg of food/day, respectively. After 7, 14, 21 and 28 days, serum levels of free tri-iodothyronine (FT3), thyroxine (FT4), testosterone and estradiol were measured. Attention was also paid to growth rate and a histological examination of testes or vaginal mucosa was carried out. In treated rats, a dose-dependent loss of appetite and a decrease in growth rate were observed, together with symptoms of polydypsia, polyuria and diarrhea. Lithium serum concentrations increased from 0.44 mM (day 7) to 1.34 mM (day 28) in Li1 rats and from 0.66 to 1.45 mM (day 14) in Li2 rats. Li2 treatment induced a high mortality after 14 days, reaching 50-60% in female and male animals. From these data, the LD50 (14 days Li2 chronic treatment) was calculated to be about 0.3 g/day per kilogram of animal, leading to Li serum concentrations of about 1.4 mM. A significant decrease of FT3 and FT4 was observed in treated rats. This effect appeared immediately for the highest dose and was more pronounced for FT3, resulting in an increase of the FT4/FT3 ratio. In males, testosterone decreased and spermatogenesis was stopped. Conversely, in females, estradiol increased in a dose-dependent manner as the animals were blocked in the diestrus phase at day 28. This finding supports a possible antagonistic effect of lithium on the estradiol receptors.

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