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1.
Nature ; 563(7731): 416-420, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429545

RESUMEN

Ribonucleotide reductase (RNR) catalyses the only known de novo pathway for the production of all four deoxyribonucleotides that are required for DNA synthesis1,2. It is essential for all organisms that use DNA as their genetic material and is a current drug target3,4. Since the discovery that iron is required for function in the aerobic, class I RNR found in all eukaryotes and many bacteria, a dinuclear metal site has been viewed as necessary to generate and stabilize the catalytic radical that is essential for RNR activity5-7. Here we describe a group of RNR proteins in Mollicutes-including Mycoplasma pathogens-that possess a metal-independent stable radical residing on a modified tyrosyl residue. Structural, biochemical and spectroscopic characterization reveal a stable 3,4-dihydroxyphenylalanine (DOPA) radical species that directly supports ribonucleotide reduction in vitro and in vivo. This observation overturns the presumed requirement for a dinuclear metal site in aerobic ribonucleotide reductase. The metal-independent radical requires new mechanisms for radical generation and stabilization, processes that are targeted by RNR inhibitors. It is possible that this RNR variant provides an advantage under metal starvation induced by the immune system. Organisms that encode this type of RNR-some of which are developing resistance to antibiotics-are involved in diseases of the respiratory, urinary and genital tracts. Further characterization of this RNR family and its mechanism of cofactor generation will provide insight into new enzymatic chemistry and be of value in devising strategies to combat the pathogens that utilize it. We propose that this RNR subclass is denoted class Ie.


Asunto(s)
Dihidroxifenilalanina/química , Dihidroxifenilalanina/metabolismo , Metales , Mycoplasma/metabolismo , Ribonucleótidos/metabolismo , Secuencia de Aminoácidos , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/metabolismo , Sistema Inmunológico/metabolismo , Hierro/metabolismo , Metales/metabolismo , Modelos Moleculares , Mycoplasma/efectos de los fármacos , Mycoplasma/enzimología , Mycoplasma/genética , Operón/genética , Oxidación-Reducción , Ribonucleótido Reductasas/química , Ribonucleótido Reductasas/metabolismo , Ribonucleótidos/química , Tirosina/química , Tirosina/metabolismo
2.
Mar Drugs ; 19(10)2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34677427

RESUMEN

Mycoplasma hyorhinis most commonly causes polyserositis and arthritis in swine and is a common contaminant during the cell culture in the laboratory. In our continuing research for diverse bioactive compounds from Bacillus subtilis 109GGC020, we discovered uncommon cyclic lipotetrapeptides showing inhibitory activities against M. hyorhinis with similar structures to previously reported bacilotetrins A and B. Bacilotetrins C-E (1-3), new cyclic lipodepsipeptides, were isolated from the EtOAc extract obtained from the fermentation of marine-derived Bacillus subtilis isolated from a marine sponge sample collected from the Gageo reef, Republic of Korea. The structures of 1-3, consisting of three leucine residues, one glutamic acid, and a ß-hydroxy fatty acid, were elucidated by detailed analysis of 1D, 2D NMR, and HR-ESIMS data. The absolute configurations of the amino acids and ß-hydroxy fatty acid were established by advanced Marfey's method and Mosher's method, respectively. The localization of L- and D-amino acids within the compounds was determined by retention time comparison of each purchased dipeptide standard to the partial hydrolysate products using LC-MS. Compounds 1-3 exhibited anti-mycoplasma activity, with an MIC value of 31 µg/mL, twofold stronger than that of the positive control, BioMycoX®. Detailed analysis and comparison of the spectroscopic data between bacilotetrins A (4) and B (5) and 1-3 led us to revise the structures of 4 and 5.


Asunto(s)
Antibacterianos/farmacología , Bacillus subtilis , Mycoplasma/efectos de los fármacos , Péptidos Cíclicos/farmacología , Animales , Antibacterianos/química , Organismos Acuáticos , Pruebas de Sensibilidad Microbiana , Péptidos Cíclicos/química , Relación Estructura-Actividad
3.
Chem Biodivers ; 18(1): e2000711, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33200537

RESUMEN

Hydroalcoholic propolis extracts from the bee species Melipona quadrifasciata have been shown to possess antimicrobial activity against different mollicute strains, but a methanolic extract (ME) could contain an increased diversity of nonpolar bioactive components with a potentially higher antimicrobial activity. The ME obtained by maceration of the propolis sample was fractionated with solvents of different polarities and then, purified by silica gel column chromatography through biomonitoring of its antimicrobial activity against mollicute strains. Analysis by gas chromatography-mass spectrometry (GC/MS) enabled the identification of compounds using the NIST library. Minimum inhibitory concentrations (MICs) of the samples were determined by broth microdilution. Anti-adhesive assays were performed with Mycoplasma pneumoniae cells. The hexane (MIC=62.5 mg/L) and dichloromethane (MIC=125 mg/L) fractions presented the most promising results against M. pneumoniae. They were fractionated into 74 subfractions, and even the best ones did not show better results (MIC>250 mg/L) than their original fractions, likely due to the loss of terpene compounds that seem to act in synergy. The dichloromethane subfraction FD4 was highlighted in the anti-adhesive assay with an inhibitory activity of 21.6 %. A synergistic effect of the nonpolar compounds in M. quadrifasciata propolis may be responsible for its antibacterial activity, but several purified components can improve its anti-adhesive properties.


Asunto(s)
Antiinfecciosos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Mycoplasma/efectos de los fármacos , Própolis/química , Animales , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Abejas , Brasil , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Hexanos/química , Metanol/química , Pruebas de Sensibilidad Microbiana , Própolis/aislamiento & purificación , Própolis/farmacología
4.
BMC Vet Res ; 16(1): 107, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-32252763

RESUMEN

BACKGROUND: Mycoplasmas primarily cause respiratory or urogenital tract infections impacting avian, bovine, canine, caprine, murine, and reptilian hosts. In animal husbandry, mycoplasmas cause reduced feed-conversion, decreased egg production, arthritis, hypogalactia or agalactia, increased condemnations, culling, and mortality in some cases. Antibiotics reduce transmission and mitigate clinical signs; however, concerning levels of antibiotic resistance in Mycoplasma gallisepticum and M. capricolum isolates exist. To address these issues, we evaluated the minimum inhibitory concentrations (MICs) of halogenated phenazine and quinoline compounds, an N-arylated NH125 analogue, and triclosan against six representative veterinary mycoplasmas via microbroth or agar dilution methods. Thereafter, we evaluated the minimum bactericidal concentration (MBC) of efficacious drugs. RESULTS: We identified several compounds with MICs ≤25 µM against M. pulmonis (n = 5), M. capricolum (n = 4), M. gallisepticum (n = 3), M. alligatoris (n = 3), M. agassizii (n = 2), and M. canis (n = 1). An N-arylated NH125 analogue, compound 21, served as the most efficacious, having a MIC ≤25 µM against all mycoplasmas tested, followed by two quinolines, nitroxoline (compound 12) and compound 20, which were effective against four and three mycoplasma type strains, respectively. Nitroxoline exhibited bactericidal activity among all susceptible mycoplasmas, and compound 21 exhibited bactericidal activity when the MBC was able to be determined. CONCLUSIONS: These findings highlight a number of promising agents from novel drug classes with potential applications to treat veterinary mycoplasma infections and present the opportunity to evaluate preliminary pharmacokinetic indices using M. pulmonis in rodents as an animal model of human infection.


Asunto(s)
Antibacterianos/farmacología , Imidazoles/farmacología , Mycoplasma/efectos de los fármacos , Fenazinas/farmacología , Quinolinas/farmacología , Pruebas de Sensibilidad Microbiana
5.
J Vet Pharmacol Ther ; 43(1): 57-66, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31667880

RESUMEN

The pharmacokinetics of tylosin were investigated in 3 groups of ducks (n = 6). They received a single dose of tylosin (50 mg/kg) by intravenous (IV), intramuscular (IM), and oral administrations, respectively. Plasma samples were collected at various time points to 24 hr post-administration to evaluate tylosin concentration over time. Additionally, tylosin residues in tissues and its withdrawal time were assessed using 30 ducks which received tylosin orally (50 mg/kg) once daily for 5 consecutive days. After IV administration, the volume of distribution, elimination half-life, area under the plasma concentration-time curve, and the total body clearance were 7.07 ± 1.98 L/kg, 2.04 hr, 19.47 µg hr/ml, and 2.82 L hr-1  kg-1 , respectively. After IM and oral administrations, the maximum plasma concentrations were 3.70 and 2.75 µg/ml achieved at 1 and 2 hr, and the bioavailability was 93.95% and 75.77%, respectively. The calculated withdrawal periods of tylosin were 13, 8, and 5 days for kidney, liver, and muscle, respectively. For the pharmacodynamic profile, the minimum inhibitory concentration for tylosin against M. anatis strain 1,340 was 1 µg/ml. The calculated optimal oral dose of tylosin against M. anatis in ducks based on the ex vivo pharmacokinetic/pharmacodynamic modeling was 61 mg kg-1  day-1 .


Asunto(s)
Antibacterianos/farmacocinética , Infecciones por Mycoplasma/veterinaria , Mycoplasma/efectos de los fármacos , Tilosina/farmacocinética , Animales , Antibacterianos/uso terapéutico , Área Bajo la Curva , Residuos de Medicamentos , Patos , Semivida , Pruebas de Sensibilidad Microbiana , Infecciones por Mycoplasma/tratamiento farmacológico , Infecciones por Mycoplasma/microbiología , Tilosina/uso terapéutico
6.
Artículo en Inglés | MEDLINE | ID: mdl-30642935

RESUMEN

Escalating levels of antibiotic resistance in mycoplasmas, particularly macrolide resistance in Mycoplasma pneumoniae and M. genitalium, have narrowed our antibiotic arsenal. Further, mycoplasmas lack a cell wall and do not synthesize folic acid, rendering common antibiotics, such as beta-lactams, vancomycin, sulfonamides, and trimethoprim, of no value. To address this shortage, we screened nitroxoline, triclosan, and a library of 20 novel, halogenated phenazine, quinoline, and NH125 analogues against Ureaplasma species and M. hominis clinical isolates from urine. We tested a subset of these compounds (n = 9) against four mycoplasma type strains (M. pneumoniae, M. genitalium, M. hominis, and Ureaplasma urealyticum) using a validated broth microdilution or agar dilution method. Among 72 Ureaplasma species clinical isolates, nitroxoline proved most effective (MIC90, 6.25 µM), followed by an N-arylated NH125 analogue (MIC90, 12.5 µM). NH125 and its analogue had significantly higher MICs against U. urealyticum isolates than against U. parvum isolates, whereas nitroxoline did not. Nitroxoline exhibited bactericidal activity against U. parvum isolates but bacteriostatic activity against the majority of U. urealyticum isolates. Among the type strains, the compounds had the greatest activity against M. pneumoniae and M. genitalium, with 8 (80%) and 5 (71.4%) isolates demonstrating MICs of ≤12.5 µM, respectively. Triclosan also exhibited lower MICs against M. pneumoniae and M. genitalium Overall, we identified a promising range of quinoline, halogenated phenazine, and NH125 compounds that showed effectiveness against M. pneumoniae and M. genitalium and found that nitroxoline, approved for use outside the United States for the treatment of urinary tract infections, and an N-arylated NH125 analogue demonstrated low MICs against Ureaplasma species isolates.


Asunto(s)
Antibacterianos/farmacología , Imidazoles/farmacología , Mycoplasma/efectos de los fármacos , Fenazinas/farmacología , Quinolinas/farmacología , Ureaplasma urealyticum/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Mycoplasma/clasificación , Mycoplasma/aislamiento & purificación , Infecciones por Mycoplasma/tratamiento farmacológico , Infecciones por Ureaplasma/tratamiento farmacológico , Ureaplasma urealyticum/aislamiento & purificación
7.
Appl Environ Microbiol ; 84(21)2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30171000

RESUMEN

One hundred seventy-eight mycoplasma strains isolated from South African poultry flocks between 2003 and 2015 were identified by full-genome sequencing and phylogenetic analysis of the 16S rRNA gene and were classified as follows: Mycoplasma gallisepticum (25%), M. gallinarum (25%), M. gallinaceum, (23%), M. pullorum (14%), M. synoviae (10%), and M. iners (3%), as well as one Acheoplasma laidlawii strain (1%). MIC testing was performed on the axenic samples, and numerous strains of each species were resistant to either chlortetracycline or tylosin or both, with variable sensitivity to enrofloxacin. The strains of all species tested remained sensitive to tiamulin, except for one M. gallinaceum sample that demonstrated intermediate sensitivity. The mutation of A to G at position 2059 (A2059G) in the 23S rRNA gene, which is associated with macrolide resistance, was found in the South African M. gallisepticum and M. synoviae strains, as well as a clear correlation between macrolide resistance in M. gallinarum and M. gallinaceum and mutations G354A and G748A in the L4 ribosomal protein and 23S rRNA gene, respectively. No correlation between resistance and point mutations in the genes studied could be found for M. pullorum Only a few strains were resistant to enrofloxacin, apart from one M. synoviae strain with point mutation D420N, which has been associated with quinolone resistance, and no other known markers for quinolone resistance were found in this study. Proportionally more antimicrobial-resistant strains were detected in M. gallinaceum, M. gallinarum, and M. pullorum than in M. gallisepticum and M. synoviae Of concern, three M. gallinaceum strains showed multidrug resistance to chlortetracycline, tylosin, and oxytetracycline.IMPORTANCE Nonpathogenic poultry Mycoplasma species are often overlooked due to their lesser impact on poultry health and production compared to the OIE-listed pathogenic strains M. gallisepticum and M. synoviae The use of antimicrobials as in-feed growth promoters and for the control of mycoplasmosis is common in poultry production across the world. Here, we provide evidence that certain nonpathogenic Mycoplasma species are acquiring multidrug resistance traits. This would have significant implications if these species, for which no vaccines are applied, are able to transfer their antibiotic resistance genes to other mycoplasmas and bacteria that may enter the human food chain.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Mycoplasma/veterinaria , Mycoplasma/efectos de los fármacos , Mycoplasma/aislamiento & purificación , Enfermedades de las Aves de Corral/microbiología , Animales , Pollos , Clortetraciclina/farmacología , Diterpenos/farmacología , Pruebas de Sensibilidad Microbiana , Mycoplasma/clasificación , Mycoplasma/genética , Infecciones por Mycoplasma/microbiología , Filogenia , Sudáfrica , Tilosina/farmacología
8.
J Transl Med ; 15(1): 100, 2017 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-28490346

RESUMEN

Hydrogen sulfide (H2S), previously only considered a toxic environmental air pollutant, is now increasingly recognized as an important signaling molecule able to modulate several cellular pathways in many human tissues. As demonstrated in recent studies, H2S is produced endogenously in response to different cellular stimuli and plays different roles in controlling a number of physiological responses. The precise role of H2S in inflammation is still largely unknown. In particular, the role of H2S in the regulation of the inflammatory response in acute and chronic infections is being actively investigated because of its potential therapeutic use. To study the effect of H2S as an anti-inflammatory mediator during bacterial infections, we developed an ex vivo model of primary cells and cell lines infected with Mycoplasma. Our data demonstrate a dichotomic effect of H2S on the NF-kB and Nrf-2 molecular pathways, which were inhibited and stimulated, respectively.


Asunto(s)
Antiinflamatorios/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Sulfuro de Hidrógeno/uso terapéutico , Enfermedad Aguda , Animales , Humanos , Modelos Biológicos , Mycoplasma/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
9.
Cell Mol Biol (Noisy-le-grand) ; 63(7): 112-115, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28838350

RESUMEN

Bacterial infections play a significant role in causing or intensifying the attacks in MS and there are reports based on the interference of Mycoplasma with a global distribution. Mycoplasma causes autoimmune attacks by imitating the host cell membrane, which is a way of resistance to antibiotics. The purpose of this study was to evaluate the molecular identification of mutations causing resistance to tetracycline in Mycoplasma isolated from MS patients. A total number of 32 cerebrospinal fluid samples and 48 urinal fluid samples were collected from MS patients. The samples were enriched in 7 PPLO broth for one night and continuous cultivation in agar PPLO and PPLO broth for one week. DNA was extracted, and then nested PCR and Doublex PCR were used for bacteria genus identification and the presence of potential tetracycline-resistant alleles (rrs4 and rrs3), respectively.  A total number of 12 samples created colonies. However, only 5 samples (1 cerebrospinal fluid and 4 urinal samples) were detected to be Mycoplasma. The urinal samples showed the desired alleles and were tetracycline-resistant. By sequencing the PCR products, it was shown that these alleles have mutated in various points. Based on the results it seems that the resistant mutated Mycoplasma can be detected in MS patients in our population and may be considered as a risk factor for the disease.


Asunto(s)
Farmacorresistencia Bacteriana/genética , Esclerosis Múltiple/microbiología , Mutación/genética , Mycoplasma/genética , Tetraciclina/farmacología , Humanos , Mycoplasma/efectos de los fármacos , Reacción en Cadena de la Polimerasa
10.
Pak J Pharm Sci ; 30(2): 541-549, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28649082

RESUMEN

The present study was conducted to investigate the quality and efficacy of commercially available preparations of tylosin and doxycycline available in the local market at Peshawar for poultry. In vitro and in vivo, tests were conducted to check the quality of these antimicrobial drugs. In vitro quality control test was performed by High performance liquid chromatographic (HPLC) and micro dilution method. In vivo, efficacy of the test drugs was checked in broilers infected with Mycoplasma gallisepticum. Results of HPLC indicated that test drug-2 contains doxycycline hydrochloride within specified limits but contain high quantity of active ingredient (Tylosin tartrate 120%). Recovery percentage of test drugs (3, 4, 5) were below the pharmacopoeial limit, which contained low quantity of tylosin tartrate (85%, 87.5%, 85%) respectively however, percent recovery of doxycycline were in the appropriate limits. All the tested drugs were effective against Mycoplasma gallisepticum and showed minimum inhibitory concentration (MIC) at 1.9µg/ml. The in vivo result indicated that all tested drugs decreased morbidity and mortality in infected chicks. The birds treated with test drugs (3 and 5) showed mortality of 9.5%, which was slightly higher than the other test groups. The current study suggested that there are incidences of substandard drugs in Pakistan and the drug regularity authorities should take strict actions against the manufacturing companies.


Asunto(s)
Doxiciclina/análisis , Doxiciclina/farmacología , Infecciones por Mycoplasma/tratamiento farmacológico , Mycoplasma/efectos de los fármacos , Tilosina/análisis , Tilosina/farmacología , Animales , Antibacterianos/análisis , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pollos , Doxiciclina/uso terapéutico , Pruebas de Sensibilidad Microbiana , Infecciones por Mycoplasma/veterinaria , Control de Calidad , Tilosina/uso terapéutico , Drogas Veterinarias/análisis , Drogas Veterinarias/farmacología , Drogas Veterinarias/uso terapéutico
11.
BMC Vet Res ; 12(1): 170, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27543140

RESUMEN

BACKGROUND: Mycoplasma sp. 1220 can induce inflammation primarily in the genital and respiratory tracts of waterfowl, leading to serious economic losses. Adequate housing and appropriate antibiotic treatment are promoted in the control of the disease. The aim of the present study was to determine the in vitro susceptibility to thirteen different antibiotics and an antibiotic combination of thirty-eight M. sp. 1220 strains isolated from geese and a duck in several parts of Hungary, Central Europe between 2011 and 2015. RESULTS: High MIC50 values were observed in the cases of tilmicosin (>64 µg/ml), oxytetracycline (64 µg/ml), norfloxacin (>10 µg/ml) and difloxacin (10 µg/ml). The examined strains yielded the same MIC50 values with spectinomycin, tylosin and florfenicol (8 µg/ml), while enrofloxacin (MIC50 5 µg/ml), doxycycline (MIC50 5 µg/ml), lincomycin (MIC50 4 µg/ml) and lincomycin-spectinomycin (1:2) combination (MIC50 4 µg/ml) inhibited the growth of the bacteria with lower concentrations. Tylvalosin (MIC50 0.5 µg/ml) and two pleuromutilins (tiamulin MIC50 0.625 µg/ml; valnemulin MIC50 ≤ 0.039 µg/ml) were found to be the most effective drugs against M. sp. 1220. However, strains with elevated MIC values were detected for all applied antibiotics. CONCLUSIONS: Valnemulin, tiamulin and tylvalosin were found to be the most effective antibiotics in the study. Increasing resistance was observed in the cases of several antibiotics. The results highlight the importance of testing Mycoplasma species for antibiotic susceptibility before therapy.


Asunto(s)
Antibacterianos/farmacología , Gansos , Infecciones por Mycoplasma/veterinaria , Mycoplasma/efectos de los fármacos , Enfermedades de las Aves de Corral/microbiología , Animales , Patos , Hungría , Pruebas de Sensibilidad Microbiana , Infecciones por Mycoplasma/microbiología , Especificidad de la Especie
12.
Antimicrob Agents Chemother ; 59(6): 3627-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25824220

RESUMEN

In this study, susceptibilities were determined for AZD0914, a spiropyrimidinetrione DNA gyrase inhibitor, azithromycin, doxycycline, and levofloxacin against Mycoplasma and Ureaplasma species. The activity of AZD0914 was comparable to that of levofloxacin and doxycycline against Mycoplasma genitalium and Mycoplasma pneumoniae. The AZD0914 MIC90 against Mycoplasma hominis was 8-fold greater than that for levofloxacin. The AZD0914 MIC90 against Ureaplasma species was 4-fold less than that for azithromycin and 8-fold less than that for levofloxacin and doxycycline.


Asunto(s)
Antibacterianos/farmacología , Barbitúricos/farmacología , Mycoplasma/efectos de los fármacos , Compuestos de Espiro/farmacología , Ureaplasma/efectos de los fármacos , Azitromicina/farmacología , Doxiciclina/farmacología , Humanos , Isoxazoles , Levofloxacino/farmacología , Pruebas de Sensibilidad Microbiana , Morfolinas , Mycoplasma genitalium/efectos de los fármacos , Mycoplasma pneumoniae/efectos de los fármacos , Oxazolidinonas
13.
Eur J Clin Microbiol Infect Dis ; 34(6): 1087-90, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25630539

RESUMEN

We investigated the antimicrobial susceptibilities of mycoplasmas in Gabonese men and women. A total of 1,332 men and women were included in the study. Sperm, urine, ureteral or vaginal swabs were collected from the subjects. Mycoplasmas identification and antimicrobial susceptibility to azithromycin, clarithromycin, erythromycin, josamycin, pristinamycin, doxycycline, tetracycline, ofloxacin and ciprofloxacin were tested using the Mycoplasma IST 2 kit. 794 subjects were positive for Mycoplasma. Respectively, 1.6 % and 82.24 % of subjects were singly infected with M. hominis and Ureaplasma urealyticum and 15.87 % had a mixed infection. M. hominis isolates were resistant to erythromycin and had an intermediate (I) to resistant (R) profile to azithromycin and clarithromycin. 84.6 % of M. hominis strains were sensitive (S) to josamycin and pristinamycin. 30.8 % and 92.3 % of M. hominis strains were sensitive to tetracycline and doxycycline, respectively. 76.9 and 84.6 % of M. hominis isolates were sensitive to ciprofloxacin and ofloxacin, respectively. The sensitivity rates of U. urealyticum strains were 45.23 %, 47.7 %, 63.84 %, 90.8 % and 92 % for azithromycin, erythromycin, clarithromycin, pristinamycin and josamycin, respectively. U. urealyticum strains showed 62.2 % and 79.7 % sensitivity to tetracycline and doxycycline, respectively. The resistance rates to azithromycin, clarithromycin and erythromycin for samples with mixed infection were 72.8 %, 84.7 % and 85.6 %, respectively. Josamycin and pristinamycin were 81.5 % effective on samples with mixed infection. The sensitivity rates of samples with mixed infection to tetracycline, doxycycline, ciprofloxacin and ofloxacin were 32 %, 69.6 %, 8.9 % and 18.5 %, respectively. Sub-Saharan Africa needs to use antibiotics rationally, as falling to do so would compromise the management of infectious diseases.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Infecciones por Mycoplasma/epidemiología , Mycoplasma/efectos de los fármacos , Mycoplasma/aislamiento & purificación , Infecciones del Sistema Genital/epidemiología , Adolescente , Adulto , Anciano , Coinfección/epidemiología , Coinfección/microbiología , Femenino , Gabón/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Mycoplasma/microbiología , Infecciones del Sistema Genital/microbiología , Infecciones por Ureaplasma/epidemiología , Infecciones por Ureaplasma/microbiología , Ureaplasma urealyticum/efectos de los fármacos , Ureaplasma urealyticum/aislamiento & purificación , Adulto Joven
14.
Poult Sci ; 103(7): 103690, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38663076

RESUMEN

Routine antibiotic administration has been used in intensive animal industries for a long time for health and production benefits. There is now a concerted effort to limit antibiotics administration to only treatment of clinically affected animals and to look for other alternative solutions combined with better husbandry practices for the benefits routine antibiotic administration seems to provide in intensive farming systems. In this paper it is argued that the benefits from routine antibiotics in chickens administration in lay are from suppression of the effects of mycoplasma infections. Mycoplasma freedom has been recommended but is not always practical. Vaccination of mycoplasma negative chickens with live mycoplasma vaccines is now being used (with biosecurity) to decrease antibiotic dependence in lay of poultry in many parts of the world.


Asunto(s)
Crianza de Animales Domésticos , Antibacterianos , Pollos , Farmacorresistencia Bacteriana , Infecciones por Mycoplasma , Enfermedades de las Aves de Corral , Animales , Crianza de Animales Domésticos/métodos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Vacunas Bacterianas , Mycoplasma/efectos de los fármacos , Infecciones por Mycoplasma/veterinaria , Infecciones por Mycoplasma/tratamiento farmacológico , Infecciones por Mycoplasma/prevención & control , Salud Única , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/prevención & control
15.
J Bacteriol ; 195(3): 429-35, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23123913

RESUMEN

Mycoplasmas, which have been shown to be the causative pathogens in recent human pneumonia epidemics, bind to solid surfaces and glide in the direction of the membrane protrusion at a pole. During gliding, the legs of the mycoplasma catch, pull, and release sialylated oligosaccharides fixed on a solid surface. Sialylated oligosaccharides are major structures on animal cell surfaces and are sometimes targeted by pathogens, such as influenza virus. In the present study, we analyzed the inhibitory effects of 16 chemically synthesized sialylated compounds on the gliding and binding of Mycoplasma mobile and Mycoplasma pneumoniae and concluded the following. (i) The recognition of sialylated oligosaccharide by mycoplasma legs proceeds in a "lock-and-key" fashion, with the binding affinity dependent on structural differences among the sialylated compounds examined. (ii) The binding of the leg and the sialylated oligosaccharide is cooperative, with Hill constants ranging from 2 to 3. (iii) Mycoplasma legs may generate a drag force after a stroke, because the gliding speed decreased and pivoting motion occurred more frequently when the number of working legs was reduced by the addition of free sialylated compounds.


Asunto(s)
Movimiento/efectos de los fármacos , Mycoplasma/efectos de los fármacos , Mycoplasma/fisiología , Polisacáridos/química , Polisacáridos/farmacología , Fenómenos Fisiológicos Bacterianos/efectos de los fármacos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Fenómenos Biomecánicos , Conformación de Carbohidratos , Regulación Bacteriana de la Expresión Génica , Unión Proteica
16.
BMC Microbiol ; 13: 32, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23394970

RESUMEN

BACKGROUND: Mycoplasmas-contamination of Orientia tsutsugamushi, one of the obligated intracellular bacteria, is a very serious problem in in vitro studies using cell cultures because mycoplasmas have significant influence on the results of scientific studies. Only a recommended decontamination method is to passage the contaminated O. tsutsugamushi strains through mice to eliminate only mycoplasmas under influence of their immunity. However, this method sometimes does not work especially for low virulent strains of O. tsutsugamushi which are difficult to propagate in mice. In this study, we tried to eliminate mycoplasmas contaminants from both high virulent and low virulent strains of the contaminated O. tsutsugamushi by repeating passage through cell cultures with antibiotics in vitro. RESULTS: We cultured a contaminated, high virulent strain of O. tsutsugamushi using a mouse lung fibroblasts cell line, L-929 cell in the culture medium containing lincomycin at various concentrations and repeated passages about every seven days. At the passage 5 only with 10 µg/ml of lincomycin, we did not detect mycoplasmas by two PCR based methods whereas O. tsutsugamushi continued good growth. During following four passages without lincomycin, mycoplasmas did not recover. These results suggested that mycoplasmas were completely eliminated from the high virulent strain of O. tsutsugamushi. Furthermore, by the same procedures with 10 µg/ml of lincomycin, we also eliminated mycoplasmas from a contaminated, low virulent strain of O. tsutsugamushi. Our additional assay showed that 50 µg/ml of lyncomycin did not inhibit the growth of O. tsutsugamushi, although MICs of many mycoplasmas contaminants were less than 6 µg/ml as shown previously. CONCLUSION: Our results showed an alternative method to eliminate mycoplasmas from the contaminated O. tsutsugamushi strains in place of in vivo passage through mice. Especially this notable method works for the decontamination not only from the high virulent strain also from the low virulent strain of O. tsutsugamushi. For further elimination, lincomycin at the limit concentration, which does not inhibit the growth of O. tsutsugamushi, can possibly eliminate most mycoplasmas from contaminated O. tsutsugamushi strains.


Asunto(s)
Antibacterianos/farmacología , Medios de Cultivo/química , Lincomicina/farmacología , Mycoplasma/efectos de los fármacos , Orientia tsutsugamushi/aislamiento & purificación , Animales , Técnicas de Cultivo de Célula/métodos , Línea Celular , Descontaminación/métodos , Fibroblastos/microbiología , Ratones , Orientia tsutsugamushi/crecimiento & desarrollo , Pase Seriado
17.
Artículo en Ruso | MEDLINE | ID: mdl-23805670

RESUMEN

AIM: Study the influence of low temperature (cold) electrolyte plasma (CEP) on survivability of some mycoplasma strains growing in agar as well as mycoplasma that most frequently contaminate transplantable human cell lines of normal and malignant origin with the aim of decontamination. MATERIALS AND METHODS: Mycoplasma hominis, Mycoplasma arginini and Aholeplasma laidlawii grown in agar and mycoplasma that contaminated transplantable human cell lines of normal (MT4) and malignant (HeLa) origin. Plasma source--Plasmatom device that generates CEP at normal atmosphere pressure and environment temperature. Exposure to plasma was carried out with adherence to the same modes for all the variants of biological substrate. The duration of exposure was selected randomly from 15 to 300 seconds. RESULTS: A pronounced bactericidal effect of high doses of CEP on all the tested mycoplasma variants exposed immediately after seeding into agar was shown. However after a passage a residual number of survived colonies was registered. Passage of colonies exposed in grown state even to high doses of CEP also showed survival of a residual number of bacteria in all the tested mycoplasma species. Exposure of M. hominis immediately after seeding to low doses of CEP resulted in formation of unusual mini-colonies identical to those isolated from humans infected by the same mycoplasma. During microbiological seeding into agar of cultural fluid from 2 spontaneously contaminated strains of transplantable human cells and exposed to CEP growth ofmycoplasma was not detected. CONCLUSION: CEP has pronounced bactericidal properties on various mycoplasma strains growing in both agar and contaminating eukaryotic cells. However even at high doses of exposure to CEP an insignificant part of bacterial cells growing in agar still survives. This may indicate a high degree of heterogeneity and adaptation of mycoplasma subjected to even such hard exposure as cold plasma with plasma-chemical mechanism of destruction of biological substrate.


Asunto(s)
Acholeplasma laidlawii/efectos de los fármacos , Adaptación Fisiológica , Mycoplasma hominis/efectos de los fármacos , Mycoplasma/efectos de los fármacos , Gases em Plasma/farmacología , Acholeplasma laidlawii/crecimiento & desarrollo , Agar , Carga Bacteriana/efectos de los fármacos , Línea Celular , Frío , Medios de Cultivo , Células HeLa , Humanos , Viabilidad Microbiana/efectos de los fármacos , Mycoplasma/crecimiento & desarrollo , Mycoplasma hominis/crecimiento & desarrollo
18.
Eksp Klin Farmakol ; 76(7): 39-42, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24006616

RESUMEN

The article describes the clinical forms of chronic hyperplastic laryngitis, characterized by persistent and recurrent course, a tendency to the formation of oncological pathology, at the expense of hyperplastic changes in the larynx, leading to a malignancy of the inflammatory process. It was demonstrated the bacterization of larynx by Epstein-Barr virus (EBV) and Mycoplasma in imbalance of system of interferon. Clinical recovery, depending on the clinical form of the disease, using cycloferon, was observed in 57.4% of patients. The inclusion in the complex of the medical support of chronic hyperplastic laryngitis inducer of interferon - cycloferon, provided the reduction of the number of relapses.


Asunto(s)
Acridinas/uso terapéutico , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Hiperplasia/tratamiento farmacológico , Inductores de Interferón/uso terapéutico , Laringitis/tratamiento farmacológico , Infecciones por Mycoplasma/tratamiento farmacológico , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Enfermedad Crónica , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/patología , Herpesvirus Humano 4/efectos de los fármacos , Herpesvirus Humano 4/fisiología , Humanos , Hiperplasia/complicaciones , Hiperplasia/inmunología , Hiperplasia/patología , Interferón-alfa/sangre , Interferón-alfa/inmunología , Interferón gamma/sangre , Interferón gamma/inmunología , Laringitis/complicaciones , Laringitis/inmunología , Laringitis/patología , Laringe/efectos de los fármacos , Laringe/inmunología , Laringe/patología , Mycoplasma/efectos de los fármacos , Mycoplasma/crecimiento & desarrollo , Infecciones por Mycoplasma/complicaciones , Infecciones por Mycoplasma/inmunología , Infecciones por Mycoplasma/patología , Prevención Secundaria
19.
Antibiot Khimioter ; 58(5-6): 24-31, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24757822

RESUMEN

The clinical course of various forms of chronic laryngitis, including contact granulomas not only persistant and relapsing, but also inclined to oncologic pathology due to hyperplastic changes in the larynx resulting in malignization was described. Inhibition of the leukocyte interferon-synthesizing activity was observed in more than 88.1% of the subjects. Pathogenic viruses were isolated from 48.2% of the patients, EBV and mycoplasma prevailing. High direct correlation between chronic laryngitis and Herpes viruses was shown. The presence of three-component virus associations in the larynx mucosa was likely indicative of the bening process malignancy. The use of the interferon inductor cycloferon in the complex surgical and medicamentous management of chronic laryngitis was shown valid. The rate of the relapses lowered to 1.7 episodes a year.


Asunto(s)
Acridinas/uso terapéutico , Infecciones por Virus de Epstein-Barr/terapia , Granuloma/terapia , Inductores de Interferón/uso terapéutico , Laringitis/terapia , Infecciones por Mycoplasma/terapia , Adulto , Enfermedad Crónica , Coinfección , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/microbiología , Infecciones por Virus de Epstein-Barr/virología , Granuloma/inmunología , Granuloma/microbiología , Granuloma/virología , Herpesvirus Humano 4/efectos de los fármacos , Herpesvirus Humano 4/inmunología , Humanos , Laringitis/inmunología , Laringitis/microbiología , Laringitis/virología , Laringe/efectos de los fármacos , Laringe/inmunología , Laringe/microbiología , Laringe/virología , Mycoplasma/efectos de los fármacos , Mycoplasma/inmunología , Infecciones por Mycoplasma/inmunología , Infecciones por Mycoplasma/microbiología , Infecciones por Mycoplasma/virología , Prevención Secundaria , Resultado del Tratamiento
20.
J Bacteriol ; 194(1): 122-30, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22001513

RESUMEN

Mycoplasma mobile glides on solid surfaces by the repeated binding of leg structures to sialylated oligosaccharide fixed on a solid surface. To obtain information about the propulsion caused by the leg, we made elongated and stiff cells using a detergent. Within 30 min after the cells were treated with 0.1% Tween 60, the cells were elongated from 0.8 µm to 2.2 µm in length while maintaining their gliding activity. Fluorescence and electron microscopy showed that a part of the cytoskeletal structure was elongated, while the localization of proteins involved in the gliding was not modified significantly. The elongated cells glided with repeated pivoting around the cellular position of gliding machinery by 10 degrees of amplitude at a frequency of 2 to 3 times per second, suggesting that the propulsion in a line perpendicular to the cell axis can occur with different timings. The pivoting speed decreased as the cell length increased, probably from the load generated by the friction. The torque required to achieve the actual pivoting increased with the cell length without saturation, reaching 54.7 pN nm at 4.3 µm in cell length.


Asunto(s)
Detergentes/farmacología , Mycoplasma/citología , Mycoplasma/efectos de los fármacos , Polisorbatos/farmacología , Fenómenos Fisiológicos Bacterianos , Fenómenos Biomecánicos , Mycoplasma/fisiología , Octoxinol/farmacología
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