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Ma Tongxun - One of the best experts on this subject based on the ideXlab platform.
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Relative bioavailability of Roxithromycin granule in healthy volunteers
Journa of Henan Medical University, 2000Co-Authors: Ma TongxunAbstract:Aim: To study the relative bioavailability of Roxithromycin granule.Methods: The Roxithromycin concentrations in serum were determined by microbiological method after a single oral dose of Roxithromycin granule and Roxithromycin tablet were respectively given to 8 volunteers in an open randomized cross over test. Results: The concentration time curves of Roxithromycin granule and tablet fitted to a two compartment open model. The C max was (11 40±1 60) mg·L -1 and (9 65±1 26) mg·L -1 ; T max was (1 36±0 24) h and (1 71±0 27) h; T 1/2 was (12 88±0 88) h and (13 46±0 95) h; AUC was (111 18±18 44) mg·h·L -1 and (108 91±16 94) mg·h·L -1 ,of Roxithromycin granule and Roxithromycin tablet respectively. The pharmacokinetic parameters obtained from our studies showed no significant difference between two formulations ( P 0 05). The relative bioavailability was (102 08±8 02)%(88 01%～115 53%) of Roxithromycin granule. Conclusion: The results of statistical analysis suggest that the two formulations be bioequivalent.
A Bryskier - One of the best experts on this subject based on the ideXlab platform.
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Roxithromycin: review of its antimicrobial activity.
The Journal of antimicrobial chemotherapy, 1998Co-Authors: A BryskierAbstract:Roxithromycin is a semi-synthetic 14-membered-ring macrolide antibiotic in which the erythronolide A lactone ring has been altered to prevent inactivation in the gastric milieu. The in-vitro activity of Roxithromycin is well documented and similar to that of other macrolide antibiotics. Roxithromycin is active against gram-positive and gram-negative cocci, gram-positive bacilli and some gram-negative bacilli, but has no significant effect on the predominant faecal flora. It also displays good activity against atypical pathogens, such as Mycobacterium avium complex, Helicobacter pylori and Borrelia spp. It penetrates and accumulates within cells, such as macrophages and polymorphonuclear neutrophils (PMNs), where it is distributed between the cytosol and cellular granules. Once inside the cells, it is active against intracellular pathogens, such as Legionella, Chlamydia, Mycobacterium, Rickettsia and Borrelia spp. Like other macrolides, Roxithromycin displays a significant post-antibiotic effect which is dependent on the pathogens under study, the concentration of Roxithromycin and the duration of exposure. In vivo, Roxithromycin is as effective or more effective than other macrolides in a wide range of infections.
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Intracellular activities of Roxithromycin used alone and in association with other drugs against Mycobacterium avium complex in human macrophages.
Antimicrobial Agents and Chemotherapy, 1995Co-Authors: N. Rastogi, V. Labrousse, A BryskierAbstract:Recent reports have shown that Roxithromycin possesses significant activity against atypical mycobacteria, including the Mycobacterium avium complex (MAC), and that its extracellular anti-MAC activity is further enhanced in two- or three-drug combinations with ethambutol, rifampin, amikacin, ofloxacin, and clofazimine. In accordance with the above data, the anti-MAC potential of Roxithromycin used alone and in combination with the above-mentioned antituberculous drugs was screened intracellularly against five clinical MAC isolates (from both human immunodeficiency virus-positive and human immunodeficiency virus-negative patients), phagocytized by human monocyte-derived macrophages. The results showed that Roxithromycin used alone and within clinically achievable levels was active against all of the MAC isolates tested. Screening of two-drug combinations showed that both rifampin and clofazimine further increased the intracellular activity of Roxithromycin against all five isolates by 35 to 80% (ethambutol, ofloxacin, and amikacin resulted in increased intracellular activity against one, two, and four isolates, respectively). For the three-drug combinations, the combination of Roxithromycin plus ethambutol used with rifampin or clofazimine was the most uniformly active against all five MAC isolates, with activity increases of 42 to 90%, followed by Roxithromycin plus ethambutol used with amikacin, which resulted in activity increases of 15 to 90%. The overall level of intracellular killing after 5 days of drug addition, in comparison with growth in untreated controls, varied from 1 to 3 log units depending on the individual MAC isolate and/or drug combination used.
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Activities of Roxithromycin used alone and in combination with ethambutol, rifampin, amikacin, ofloxacin, and clofazimine against Mycobacterium avium complex.
Antimicrobial Agents and Chemotherapy, 1994Co-Authors: N. Rastogi, K. S. Goh, A BryskierAbstract:Preliminary studies showed that Roxithromycin possessed significant in vitro activity against a variety of atypical mycobacteria such as the Mycobacterium avium complex, M. scrofulaceum, M. szulgai, M. malmoense, M. xenopi, M. marinum, and M. kansasii and rare pathogens such as M. chelonae and M. fortuitum. In this investigation, radiometric MICs of Roxithromycin, ethambutol, rifampin, amikacin, ofloxacin, and clofazimine for 10 clinical isolates of the M. avium complex (5 each from human immunodeficiency virus [HIV]-positive and HIV-negative patients) were determined. Roxithromycin MICs against all the isolates were below the reported maximum concentration of drug in serum at the routine pH of 6.8, and the MICs were further lowered by 1 to 2 dilutions at a pH of 7.4. In vitro enhancement of Roxithromycin activity against all strains was further investigated by the previously established Bactec 460-TB method by combining the drugs at sub-MIC levels. Antibacterial activity of Roxithromycin was enhanced in all 10 strains by ethambutol, in 3 strains each by rifampin and clofazimine, in 2 strains by amikacin, and in 1 strain by ofloxacin. In vitro screening of three-drug combinations showed that combinations of Roxithromycin, ethambutol, and a third potential anti-M. avium drug (rifampin, amikacin, ofloxacin, or clofazimine) resulted in further enhancement of activity in 13 out of 20 drug combinations screened.
Henri Monteil - One of the best experts on this subject based on the ideXlab platform.
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Penetration of Roxithromycin into gingival tissue
Diagnostic Microbiology and Infectious Disease, 1992Co-Authors: François Jehl, René Kolbe, Andrès Scheimberg, Martine Rosembaum, Henri MonteilAbstract:Abstract Roxithromycin is a new macrolide with an antibacterial spectrum similar to that of erythromycin. Absorption is rapid and complete, resulting in high serum levels and a long half-life. Tissue distribution is extensive and sustained, as shown by the high concentrations measured in the lung, prostate, ovaries, liver, kidney, and skin. In this study, we measured the penetration of Roxithromycin into gingibal tissue at steady state in 30 patients treated orally with 150 mg every 12 hr for 5 days. Tissue specimens were sampled at 2, 4, 6, 8, or 12 hr ( n = 6 each time) after dose 10, and blood samples were taken simultaneously. Serum and tissue concentrations of Roxithromycin were measured by high-performance liquid chromatography. The peak serum level, reached 4 hr after dosing, was 6.60 ± 1.15 μ g/ml. The peak tissue level was 4.63 ± 1.84 μ g/g and was reached after 8 hr. From 4 to 10 hr after dosing, tissue concentrations were > 2 μg/g, that is, higher thant the MIC 90 of Roxithromycin against most oral pathogens. These data support the use of Roxithromycin in the treatment of oral infections.
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Penetration of Roxithromycin into gingival tissue.
Diagnostic microbiology and infectious disease, 1992Co-Authors: François Jehl, A. Scheimberg, René Kolbe, Martine Rosembaum, Henri MonteilAbstract:Roxithromycin is a new macrolide with an antibacterial spectrum similar to that of erythromycin. Absorption is rapid and complete, resulting in high serum levels and a long half-life. Tissue distribution is extensive and sustained, as shown by the high concentrations measured in the lung, prostate, ovaries, liver, kidney, and skin. In this study, we measured the penetration of Roxithromycin into gingival tissue at steady state in 30 patients treated orally with 150 mg every 12 hr for 5 days. Tissue specimens were sampled at 2, 4, 6, 8, or 12 hr (n = 6 each time) after dose 10, and blood samples were taken simultaneously. Serum and tissue concentrations of Roxithromycin were measured by high-performance liquid chromatography. The peak serum level, reached 4 hr after dosing, was 6.60 +/- 1.15 micrograms/ml. The peak tissue level was 4.63 +/- 1.84 micrograms/g and was reached after 8 hr. From 4 to 10 hr after dosing, tissue concentrations were greater than 2 micrograms/g, that is, higher than the MIC90 of Roxithromycin against most oral pathogens. These data support the use of Roxithromycin in the treatment of oral infections.
A. Scheimberg - One of the best experts on this subject based on the ideXlab platform.
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Roxithromycin versus penicillin in the treatment of erysipelas in adults: a comparative study
The British journal of dermatology, 1992Co-Authors: Philippe Bernard, Y. Rezvani, P. Plantin, H. Roger, Bruno Sassolas, E. Villaret, V. Legrain, Jean-claude Roujeau, A. ScheimbergAbstract:A prospective, randomized, multicentre trial was conducted to evaluate the efficacy and safety of Roxithromycin (150 mg b.i.d. orally) and penicillin (2.5 MU x 8 daily intravenously, then 6 MU daily orally) in the treatment of hospitalized adult patients with erysipelas. Seventy-two patients entered the study. Thirty-one patients in the Roxithromycin group and 38 patients in the penicillin group completed the trial. The overall efficacy rates (cure without additional antibiotics) were 84% (26/31) in the Roxithromycin group and 76% (29/38) in the penicillin group (P = 0.43). No side-effects were observed in the Roxithromycin-treated patients whereas rashes occurred in two cases in the penicillin group, leading to exclusion from the study. Oral Roxithromycin can thus be considered an effective and well-tolerated treatment for erysipelas in adult hospitalized patients.
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Penetration of Roxithromycin into gingival tissue.
Diagnostic microbiology and infectious disease, 1992Co-Authors: François Jehl, A. Scheimberg, René Kolbe, Martine Rosembaum, Henri MonteilAbstract:Roxithromycin is a new macrolide with an antibacterial spectrum similar to that of erythromycin. Absorption is rapid and complete, resulting in high serum levels and a long half-life. Tissue distribution is extensive and sustained, as shown by the high concentrations measured in the lung, prostate, ovaries, liver, kidney, and skin. In this study, we measured the penetration of Roxithromycin into gingival tissue at steady state in 30 patients treated orally with 150 mg every 12 hr for 5 days. Tissue specimens were sampled at 2, 4, 6, 8, or 12 hr (n = 6 each time) after dose 10, and blood samples were taken simultaneously. Serum and tissue concentrations of Roxithromycin were measured by high-performance liquid chromatography. The peak serum level, reached 4 hr after dosing, was 6.60 +/- 1.15 micrograms/ml. The peak tissue level was 4.63 +/- 1.84 micrograms/g and was reached after 8 hr. From 4 to 10 hr after dosing, tissue concentrations were greater than 2 micrograms/g, that is, higher than the MIC90 of Roxithromycin against most oral pathogens. These data support the use of Roxithromycin in the treatment of oral infections.
Prabhati Ray - One of the best experts on this subject based on the ideXlab platform.
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ANTI-CYTOTOXIC AND ANTI-INFLAMMATORY EFFECTS OF THE MACROLIDE ANTIBIOTIC Roxithromycin IN SULFUR MUSTARD-EXPOSED HUMAN AIRWAY
2016Co-Authors: Epithelial Cells, Xiugong Gao, Radharaman Ray, Yan Xiao, Peter E. Barker, Prabhati RayAbstract:Inhalation of sulfur mustard (SM) causes airway inflammation and injury. There is increasing evidence of the effectiveness of macrolide antibiotics in treating chronic airway inflammatory diseases. In this study, the anti-cytotoxic and anti-inflammatory effects of a representative macrolide antibiotic, Roxithromycin, were tested in vitro using SM-exposed normal human small airway epithelial (SAE) cells and bronchial/tracheal epithelial (BTE) cells. Cells were exposed to varying concentrations of SM with or without Roxithromycin. Cytotoxicity was measured with the MTS assay and Calcein AM/ethidium homodimer (EthD-1) fluorescence staining. Cytokine protein expression was analyzed by enzyme-linked immunosorbent assay (ELISA) and cytokine mRNA expression by real-time RT-PCR. Inducible nitric oxide synthase (iNOS) protein expression was examined by a new immunocytochemical method using quantum dots as the fluorophore. Our results show that Roxithromycin decreased SM cytotoxicity in both SAE and BTE cells. Also, Roxithromycin inhibited the SM-stimulated over-production of the proinflammatory cytokines interleukin (IL)-1β, IL-6, IL-8 and TNF at both the mRNA level and the protein level. In addition, Roxithromycin inhibited the SM-induced overexpression of iNOS. In conclusion, the present study demonstrates that Roxithromycin has anti-cytotoxic and anti-inflammatory activities in human airway epithelial cells that likely depend on the ability of Roxithromycin to down-regulate the production of proinflammatory mediators and cytokines, and suggests that macrolide antibiotics may serve as potential vesicant respiratory therapeutics through mechanisms independent of their antibacterial activity. 1
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pathological studies on the protective effect of a macrolide antibiotic Roxithromycin against sulfur mustard inhalation toxicity in a rat model
Toxicologic Pathology, 2011Co-Authors: Xiugong Gao, D R Anderson, Ammon W Brown, Hsiuling Lin, Jack Amnuaysirikul, Aileen L Chua, Wesley W Holmes, Prabhati RayAbstract:Macrolide antibiotics have been shown to protect airway epithelial cells and macrophages from sulfur mustard (SM)-induced cytotoxicity. In the current study, the efficacy of Roxithromycin in ameliorating SM-induced respiratory injury was further evaluated in a rat model. Anesthetized rats (N = 8/group) were intratracheally exposed to SM by vapor inhalation. For the drug treatment groups, rats were orally given 10, 20, or 40 mg/kg Roxithromycin one hr prior to exposure and every twenty-four hr thereafter. After one, three, or seven days of treatment, sections of the lung were examined and scored for histopathological parameters. Treatment with Roxithromycin ameliorated many of the symptoms caused by SM in some animals. In particular, treatment at 40 mg/kg for three days showed significant improvements (p < .05) over the untreated group. When the evaluation was focused on trachea, treatment with Roxithromycin for three days showed a trend of dose-dependent protection; moreover, the groups treated with 20 or 40 mg/kg of Roxithromycin were statistically different (p < .001 and p < .05, respectively) from the untreated group. These results suggest that Roxithromycin protects against some damages associated with SM injury in the lung, particularly in the upper respiratory tract.
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inhibition of sulfur mustard induced cytotoxicity and inflammation by the macrolide antibiotic Roxithromycin in human respiratory epithelial cells
BMC Cell Biology, 2007Co-Authors: Xiugong Gao, Radharaman Ray, Yan Xiao, Peter E. Barker, Prabhati RayAbstract:Sulfur mustard (SM) is a potent chemical vesicant warfare agent that remains a significant military and civilian threat. Inhalation of SM gas causes airway inflammation and injury. In recent years, there has been increasing evidence of the effectiveness of macrolide antibiotics in treating chronic airway inflammatory diseases. In this study, the anti-cytotoxic and anti-inflammatory effects of a representative macrolide antibiotic, Roxithromycin, were tested in vitro using SM-exposed normal human small airway epithelial (SAE) cells and bronchial/tracheal epithelial (BTE) cells. Cell viability, expression of proinflammatory cytokines including interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor (TNF), and expression of inducible nitric oxide synthase (iNOS) were examined, since these proinflammatory cytokines/mediators are import indicators of tissue inflammatory responses. We suggest that the influence of Roxithromycin on SM-induced inflammatory reaction could play an important therapeutic role in the cytotoxicity exerted by this toxicant. MTS assay and Calcein AM/ethidium homodimer (EthD-1) fluorescence staining showed that Roxithromycin decreased SM cytotoxicity in both SAE and BTE cells. Also, Roxithromycin inhibited the SM-stimulated overproduction of the proinflammatory cytokines IL-1β, IL-6, IL-8 and TNF at both the protein level and the mRNA level, as measured by either enzyme-linked immunosorbent assay (ELISA) or real-time RT-PCR. In addition, Roxithromycin inhibited the SM-induced overexpression of iNOS, as revealed by immunocytochemical analysis using quantum dots as the fluorophore. The present study demonstrates that Roxithromycin has inhibitory effects on the cytotoxicity and inflammation provoked by SM in human respiratory epithelial cells. The decreased cytotoxicity in Roxithromycin-treated cells likely depends on the ability of the macrolide to down-regulate the production of proinflammatory cytokines and/or mediators. The results obtained in this study suggest that macrolide antibiotics may serve as potential vesicant respiratory therapeutics through mechanisms independent of their antibacterial activity.
