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1.
Trop Biomed ; 40(1): 115-123, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356011

RESUMO

Toxoplasma gondii, the etiologic agent of toxoplasmosis, infects about 30 - 50% of the world population. The currently available anti-Toxoplasma agents have serious limitations. The present study aimed to investigate the effects of two antimalarials; buparvaquone (BPQ) and chloroquine (CQ), on immunocompromised mice with chronic cerebral toxoplasmosis, using spiramycin as a reference drug. The assessed parameters included the estimation of mortality rates (MR) among mice of the different study groups, in addition to the examination of the ultrastructural changes in the brain tissues by transmission electron microscopy. The results showed that only CQ treatment could decrease the MR significantly with zero deaths, while both spiramycin and BPQ caused an insignificant reduction of MR compared to the infected non-treated group. All the used drugs decreased the number of mature ruptured cysts significantly compared to the infected non-treated group, while only CQ increased the number of atrophic and necrotic cysts significantly. Furthermore, both spiramycin and BPQ improved the microvasculopathy and neurodegeneration accompanying the infection with different degrees of reactive astrocytosis and neuronal damage with the best results regarding the repair of the microvascular damage with less active glial cells, and normal neurons in the CQ-treated group. In conclusion, this study sheds light on CQ and its excellent impact on treating chronic cerebral toxoplasmosis in an immunocompromised mouse model.


Assuntos
Cistos , Espiramicina , Toxoplasma , Toxoplasmose Animal , Toxoplasmose Cerebral , Animais , Camundongos , Espiramicina/farmacologia , Espiramicina/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Modelos Animais de Doenças , Toxoplasmose Animal/tratamento farmacológico
2.
Pathog Glob Health ; 117(7): 664-673, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37032491

RESUMO

Toxoplasmosis is a frequent disease with an estimated prevalence of more than one billion human cases worldwide and over one million new infections each year. It is classified as a neglected tropical disease by the CDC since 2019. The disease may pass unnoticed in healthy individuals but could be fatal in the immunocompromised. Moreover, no effective treatment is available against the chronic form of the disease. Available anti-Toxoplasma drugs are associated with many side effects. Therefore, search for new more reliable, more efficient, and less toxic therapeutic agents is a continuous endeavor. This study assesses the potential use of nitrofurantoin, a compound with well-established antimicrobial properties, as a potential anti-Toxoplasma drug in vivo. It compares its efficacy to the commonly used anti-Toxoplasma agent spiramycin by molecular and histopathological methods in acute and chronic infection. The results demonstrate a significant ability to eliminate the parasite (P < 0.001) whether used as mono- or combined therapy with spiramycin in the acute and chronic stages. When compared to the anti-Toxoplasma drug spiramycin, nitrofurantoin achieved similar efficacy in the acute and chronic infection (P = 0.65 and P = 0.096, respectively). However, better results were obtained when using a combination of both drugs (P < 0.001). Additionally, nitrofurantoin showed good inhibitory effects on the inflammatory process in the liver, kidney, and uterus of the experimentally infected animals. In conclusion, nitrofurantoin can be considered as a potential anti-Toxoplasma agent. Nevertheless, further studies are recommended before consideration for clinical trials.


Assuntos
Espiramicina , Toxoplasma , Toxoplasmose , Feminino , Humanos , Animais , Camundongos , Nitrofurantoína/uso terapêutico , Nitrofurantoína/farmacologia , Espiramicina/uso terapêutico , Espiramicina/farmacologia , Infecção Persistente , Modelos Animais de Doenças , Toxoplasmose/tratamento farmacológico
3.
Eur Rev Med Pharmacol Sci ; 27(2 Suppl): 44-50, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36971220

RESUMO

OBJECTIVE: Through a cell culture test, we analyzed the cytotoxic effects of topical spiramycin on NIH/3T3 fibroblast cells. MATERIALS AND METHODS: Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin was used for the growth of NIH/3T3 fibroblast cells in a 5% CO2 incubator. Spiramycin's cytotoxicity was measured using the MTT assay. 5,000 NIH/3T3 cells per well of a 96-well plate were seeded in each well, and the cells were treated with spiramycin (3.13-100 µM) for 24, 48 and 72 hours while the plates were incubated at 37°C in a humidified 5% CO2 atmosphere. First, 105 NIH/3T3 cells were seeded onto coverslips in 6-well plates for morphological analysis of both untreated and spiramycin-treated cells. For 24 hours, NIH/3T3 cells were exposed to a 100 µM dosage of spiramycin. The cells in the control group were grown in complete growth media alone. RESULTS: Spiramycin was non-toxic to NIH/3T3 fibroblast cells in a MTT test. The concentration of spiramycin used to stimulate cell growth increased as the concentration was increased. After 24 and 48 hours of treatment with 100 µM NIH/3T3, the cells showed the most significant increase in size. Cell viability was shown to be significantly reduced at spiramycin doses of 50 and 100 µM. All MTT findings revealed that spiramycin enhanced cell viability and was not harmful to the fibroblast cells for short-term application of 24 and 48 hours but lowered the viability of fibroblast cells at the doses of 50 and 100 µM for long-term application duration of 72 hours. Confocal micrographs showed that spiramycin treatment did not affect the cytoskeleton or nucleus of fibroblast cells, in contrast to the control NIH/3T3 cells. Both untreated and treated with spiramycin, fibroblast cells were found to be fusiform and compact, with their nuclei remaining unaltered and unreduced in size. CONCLUSIONS: It was concluded that spiramycin has a beneficial effect on fibroblast cells and is safe for use over short periods. Spiramycin reduced fibroblast cell viability when applied for 72 hours. Confocal micrographs showed that fibroblast cell skeletons and nuclei were unharmed and undamaged, that cell shapes were fusiform and compact, and that nuclei were neither broken nor shrunken. Topical spiramycin could be recommended for septorhinoplasty procedures due to anti-inflammatory effects for short-term usage if clinical trials will confirm experimental data.


Assuntos
Espiramicina , Animais , Camundongos , Espiramicina/farmacologia , Dióxido de Carbono , Fibroblastos , Células NIH 3T3 , Técnicas de Cultura de Células
4.
Exp Parasitol ; 248: 108515, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36958594

RESUMO

Latent toxoplasmosis mostly reactivates which could result in acute encephalitis. Chronic toxoplasmosis treatments are severely constrained by Toxoplasma cyst resistance. Novel therapeutic approaches are therefore becoming more essential. In this study, the effects of levamisole (LEVA) and spiramycin on the early and late stages of experimental toxoplasmosis are investigated. MATERIALS AND METHODS: Seventy-five Me49 Toxoplasma gondii infected Swiss albino mice were divided into five groups; (GI): noninfected control group; (GII): infected untreated control group; (GIII): infected- LEVA treated group; (GIV): infected and received combination of spiramycin and LEVA and (GV): infected-spiramycin treated group. The impact was assessed through brain cyst count by Quantitative Real-Time Polymerase Chain Reaction (PCR), interferon gamma (IFN-γ) assay, histopathological study, and total blood counts. RESULTS: The progression of chronic toxoplasmosis could only be partially controlled by using either levamisole or spiramycin as a separate drug. The combined spiramycin and levamisole treatment significantly decreased the burden of Toxoplasma brain cyst, increased IFN-γ level, total blood parameters and improved the histopathological features especially at the late stage of infection. IN CONCLUSION: Levamisole effectively modulated Toxoplasma-induced immune responses, resulting in chronic toxoplasmosis remission. Further clinical trials will be needed to study the effect of these combination in HIV/AIDS (human immunodeficiency virus) patients with toxoplasmosis.


Assuntos
Espiramicina , Toxoplasma , Toxoplasmose , Animais , Camundongos , Humanos , Espiramicina/farmacologia , Espiramicina/uso terapêutico , Levamisol/farmacologia , Levamisol/uso terapêutico
5.
Acta Trop ; 239: 106823, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36608751

RESUMO

Treatment of chronic toxoplasmosis is challenging as the available drugs are effective only in the acute stage. Therefore, the current study aimed to investigate Nigella sativa oil (NSO) and wheat germ oil (WGO) loaded on copper-benzene tricarboxylic acid metal organic framework (Cu-BTC MOF) for treating chronic toxoplasmosis in a murine model. Eighty mice were divided into 8 groups (G); uninfected untreated negative control (GI), infected untreated positive control (GII), infected and treated with: Spiramycin (GIII), Spiramycin@Cu-BTC (GIV), Cu-BTC (GV), WGO@Cu-BTC (GVI), NSO@Cu-BTC (GVII) and combined WGO+NSO@Cu-BTC (GVIII). The infected groups were orally inoculated with 10 Toxoplasma gondii Me49 strain cysts/mouse. All drugs were orally administered for 14 consecutive days starting 8 weeks post-infection (wpi). The therapeutic efficacy was evaluated by parasitological (survival rate of mice and brain cyst burden) and histopathological (brain, liver, kidney, eye) parameters. At the end of 2-weeks therapy, the highest therapeutic outcome was achieved with GVII and GVIII exhibiting 100% survival, 64.3% and 51.4% reduction of brain cysts, and an apparent amendment of pathological insults. In the next place was GVI with 90% survival, 49.5% reduction of cysts and marked amelioration of pathological lesions. Meanwhile, GIII and GIV showed 80% survival, 42.4% and 41.8% reduction of cysts as well as minimal to moderate alleviation of tissue damage. The lowest effect was obtained with GV resulting in 70% survival and 24.4% reduction of cysts. The current results support the assertion that the new metal-based nanocomposites can be promising remedies of chronic toxoplasmosis particularly if conjugated with natural herbal extracts as NSO and WGO.


Assuntos
Estruturas Metalorgânicas , Espiramicina , Toxoplasma , Toxoplasmose , Animais , Camundongos , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/uso terapêutico , Espiramicina/farmacologia , Espiramicina/uso terapêutico , Toxoplasmose/tratamento farmacológico
6.
Exp Parasitol ; 242: 108397, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36195177

RESUMO

Botanical medicinal plants have aroused our interest to deal with Toxoplasmosis which can causes serious public health problems. Nipagic acid, gallic acid, ethyl gallate, phloretic acid, protocatechuic acid, methyl p-coumarate, arbutin, and homoprotocatechuic acid are first isolated from Orostachys malacophylla (Pallas) Fischer, their inhibition rate, survival rate, biochemical and viscera index are evaluated using gastric epithelia strain-1(GES-1). Among them, arbutin can effectively prolong the survival time of mice acutely infected with T. gondii, and exhibit the same curative effect as Spiramycin (Spi) group in terms of the glutathione (GSH) and malondialdehyde (MDA) content, alleviate hepatomegaly and splenomegaly. Structure-activity relationship (SAR) and molecular docking implies that phenolic hydroxyl group would be preferred for improvement of activity. In a summary, arbutin is a potential anti-T. gondii candidate for clinical application.


Assuntos
Espiramicina , Toxoplasma , Animais , Camundongos , Espiramicina/farmacologia , Simulação de Acoplamento Molecular , Arbutina/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Malondialdeído , Glutationa , Ácido Gálico/farmacologia , Ácido Gálico/uso terapêutico
7.
BMC Microbiol ; 22(1): 152, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35681117

RESUMO

BACKGROUND: Ribosome stalling on ermBL at the tenth codon (Asp) and mRNA stabilization are believed to be mechanisms by which erythromycin (Ery) induces ermB expression. Expression of ermB is also induced by 16-membered ring macrolides (tylosin, josamycin and spiramycin), but the mechanism underlying this induction is unknown. METHODS: We introduced premature termination codons, alanine-scanning mutagenesis and amino acid mutations in ermBL and ermBL2. RESULTS: In this paper, we demonstrated that 16-membered ring macrolides can induce ermB expression but not ermC expression. The truncated mutants of the ermB-coding sequence indicate that the regulatory regions of ermB whose expression is induced by Ery and 16-membered ring macrolides are different. We proved that translation of the N-terminal region of ermBL is key for the induction of ermB expression by Ery, spiramycin (Spi) and tylosin (Tyl). We also demonstrated that ermBL2 is critical for the induction of ermB expression by erythromycin but not by 16-membered ring macrolides. CONCLUSIONS: The translation of ermBL and the RNA sequence of the C-terminus of ermBL are critical for the induction of ermB expression by Spi and Tyl.


Assuntos
Eritromicina , Espiramicina , Antibacterianos/farmacologia , Eritromicina/farmacologia , Macrolídeos/farmacologia , Espiramicina/farmacologia , Tilosina
8.
Molecules ; 27(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630676

RESUMO

Drug repurposing is a simple concept with a long history, and is a paradigm shift that can significantly reduce the costs and accelerate the process of bringing a new small-molecule drug into clinical practice. We attempted to uncover a new application of spiramycin, an old medication that was classically prescribed for toxoplasmosis and various other soft-tissue infections; specifically, we initiated a study on the anti-inflammatory capacity of spiramycin. For this purpose, we used murine macrophage RAW 264.7 as a model for this experiment and investigated the anti-inflammatory effects of spiramycin by inhibiting the production of pro-inflammatory mediators and cytokines. In the present study, we demonstrated that spiramycin significantly decreased nitric oxide (NO), interleukin (IL)-1ß, and IL-6 levels in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Spiramycin also inhibited the expression of NO synthase (iNOS), potentially explaining the spiramycin-induced decrease in NO production. In addition, spiramycin inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs); extracellular signal-regulated kinase (ERK) and c-Jun N terminal kinase (JNK) as well as the inactivation and subsequent nuclear translocation of nuclear factor κB (NF-κB). This indicated that spiramycin attenuates macrophages' secretion of IL-6, IL-1ß, and NO, inducing iNOS expression via the inhibition of the NF-κB and MAPK signaling pathways. Finally, we tested the potential application of spiramycin as a topical material by human skin primary irritation tests. It was performed on the normal skin (upper back) of 31 volunteers to determine whether 100 µM and µM of spiramycin had irritation or sensitization potential. In these assays, spiramycin did not induce any adverse reactions. In conclusion, our results demonstrate that spiramycin can effectively attenuate the activation of macrophages, suggesting that spiramycin could be a potential candidate for drug repositioning as a topical anti-inflammatory agent.


Assuntos
Anti-Inflamatórios , Macrófagos , Espiramicina , Animais , Anti-Inflamatórios/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Células RAW 264.7 , Espiramicina/farmacologia
9.
Eur J Med Res ; 26(1): 143, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895348

RESUMO

PURPOSE: We aimed to investigate the effect of antepartum treatment with spiramycin with or without subsequent pyrimethamine-sulfonamide-folinic acid, compared to no treatment, on the rate of mother-to-child transmission (MTCT) of Toxoplasma gondii (T. gondii) and incidence/severity of sequelae in the offspring. METHODS: Embase and PubMed were searched for literature on spiramycin in pregnant women suspected/diagnosed with T. gondii infection. Meta-analyses were performed using random-effects model. RESULTS: Thirty-three studies (32 cohorts and 1 cross-sectional study), with a total of 15,406 mothers and 15,250 offspring, were pooled for analyses. The MTCT rate for all treated patients was significantly lower than the untreated [19.5% (95% CI 14-25.5%) versus 50.7% (95% CI 31.2-70%), p < 0.001]. The transmission rate in patients on spiramycin monotherapy was also significantly lower than untreated [17.6% (95% CI 9.9-26.8%) versus 50.7% (95% CI 31.2-70%), p < 0.001]. CONCLUSION: Results indicate significant reduction in MTCT rates following spiramycin treatment of suspected/diagnosed maternal T. gondii infection.


Assuntos
Doenças Negligenciadas/prevenção & controle , Estudos Observacionais como Assunto , Complicações Infecciosas na Gravidez/prevenção & controle , Espiramicina/farmacologia , Antibacterianos/farmacologia , Feminino , Humanos , Gravidez
10.
Biomed Res ; 41(6): 259-268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33268670

RESUMO

Recently, opportunistic nosocomial infections caused by Acinetobacter baumannii have become increasingly prevalent worldwide. The pathogen often establishes biofilms that adhere to medical devices, causing chronic infections refractory to antimicrobial therapy. Clinical reports have indicated that some macrolide antibiotics are effective against chronic biofilm-related infections. In this study, we examined the direct anti-biofilm effects of seven macrolides (azithromycin, clarithromycin, erythromycin, josamycin, spiramycin, fidaxomicin, and ivermectin) on A. baumannii using a simple and newly established in vitro assay system for the swift and serial spectrophotometric determinations of two biofilm-amount indexes of viability and biomass. These macrolides were found to possess direct anti-biofilm effects exerting specific anti-biofilm effects not exclusively depending on their bacteriostatic/bactericidal effects. The anti-biofilm effect of azithromycin was found to be the strongest, while those of fidaxomicin and ivermectin were weak and limited. These results provide insights into possible adjunctive chemotherapy with macrolides for A. baumannii infection. Common five macrolides also interfered with the Agrobacterium tumefaciens NTL(pCF218) (pCF372) bioassay system of N-acyl homoserine lactones, providing insights into sample preparation for the bioassay, and putatively suggesting the actions of macrolides as remote signals in bacterial quorum sensing systems.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Acil-Butirolactonas/antagonistas & inibidores , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/metabolismo , Acil-Butirolactonas/metabolismo , Agrobacterium tumefaciens/efeitos dos fármacos , Agrobacterium tumefaciens/crescimento & desenvolvimento , Agrobacterium tumefaciens/metabolismo , Azitromicina/farmacologia , Biofilmes/crescimento & desenvolvimento , Bioensaio , Claritromicina/farmacologia , Eritromicina/farmacologia , Fidaxomicina/farmacologia , Humanos , Ivermectina/farmacologia , Josamicina/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Espiramicina/farmacologia
11.
Exp Parasitol ; 216: 107935, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32569599

RESUMO

Toxoplasma gondii is an important pathogen that causes serious public health problems. Currently, therapeutic drugs for toxoplasmosis cause serious side effects, and more effective and novel substances with relatively low toxicity are urgently needed. Ursolic acid (UA) has many properties that can be beneficial to healthcare. In this study, we synthesized eight series of UA derivatives bearing a tetrazole moiety and evaluated their anti-T. gondii activity in vitro using spiramycin as a positive control. Most of the synthesized derivatives exhibited better anti-T. gondii activity in vitro than UA, among which compound 12a exhibited the most potent anti-T. gondii activity. Furthermore, the results of biochemical parameter determination indicated that 12a effectively restored the normal body weight of mice infected with T. gondii, reduced hepatotoxicity, and exerted significant anti-oxidative effects compared with the findings for spiramycin. Additionally, our molecular docking study indicated that the synthesized compounds could act as potential inhibitors of T. gondii calcium-dependent protein kinase 1 (TgCDPK1), with 12a possessing strong affinity for TgCDPK1 via binding to the key amino acids GLU129 and TYR131.


Assuntos
Anti-Infecciosos/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose/tratamento farmacológico , Triterpenos/farmacologia , Alanina Transaminase/sangue , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Aspartato Aminotransferases/sangue , Coccidiostáticos/química , Coccidiostáticos/farmacologia , Modelos Animais de Doenças , Feminino , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Malondialdeído/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Tamanho do Órgão/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases , Distribuição Aleatória , Espiramicina/farmacologia , Baço/efeitos dos fármacos , Baço/patologia , Triterpenos/química , Triterpenos/uso terapêutico
12.
Microb Drug Resist ; 26(7): 727-731, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32031922

RESUMO

Objectives: The aim of the study was to characterize phenotypically and genotypically an uncommon mechanism of resistance to macrolides, lincosamides, and streptogramins (MLS) in a Streptococcus milleri group clinical isolate. Materials and Methods: The isolate UCN96 was recovered from an osteoradionecrosis wound, and was identified using the matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and the partial sequencing of the sodA gene. Antimicrobial susceptibility testing were carried out by the disk diffusion method and minimal inhibitory concentrations (MICs) were determined by the broth microdilution technique. PCR screening was performed for MLS resistance genes described in Gram-positive bacteria. Specific mutations in the ribosomal proteins L3-, L4-, and L22-encoding genes were also screened and those in domain V of the 23S rRNA gene (rrl). The number of mutated copies of the rrl gene was determined using amplification-refractory mutation system quantitative-polymerase chain reaction (qPCR) analysis. Results: The clinical isolate UCN96 was unambiguously identified as Streptococcus constellatus. It was susceptible to all macrolides and lincosamides (ML) antibiotics except spiramycin (MIC >256 mg/L) while it was also resistant to streptogramins. Screening for all acquired resistance genes was negative and no mutation was found in genes coding for L3, L4, and L22 ribosomal proteins. Of interest, a single mutation, A2062C (according to Escherichia coli numbering), was detected in the domain V of 23S rRNA. Conclusion: Mutations at the position 2062 of 23S rRNA have been detected once in Streptococcus pneumoniae, and not yet in other Streptococcus spp. This mechanism is very likely uncommon in Gram-positive bacteria because different copies of 23S rRNA operons should be mutated for development of such a resistance pattern.


Assuntos
Antibacterianos/farmacologia , Eritromicina/farmacologia , RNA Ribossômico 23S/genética , Espiramicina/farmacologia , Streptococcus milleri (Grupo)/efeitos dos fármacos , Streptococcus milleri (Grupo)/genética , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Genótipo , Humanos , Lincosamidas/farmacologia , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Streptococcus constellatus/efeitos dos fármacos , Streptococcus constellatus/genética , Estreptograminas/farmacologia , Superóxido Dismutase/genética
13.
PLoS One ; 14(11): e0224903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31697761

RESUMO

Mycoplasma synoviae (MS) is a highly prevalent bacterial species in poultry causing disease and severe economic losses. Antibiotic treatment is one of the control strategies that can be applied to contain clinical outbreaks in MS-free flocks, especially because this bacterium can be transmitted in ovo. It becomes, then, very important for veterinarians to know the antibiotic susceptibility of the circulating strains in order to choose the most appropriate first-line antibiotic molecule as a proactive role in fighting antibiotic resistance. We evaluated the Minimum Inhibitory Concentrations (MICs) of enrofloxacin, oxytetracycline, doxycycline, erythromycin, tylosin, tilmicosin, spiramycin, tiamulin, florfenicol and lincomycin for MS isolates collected between 2012 and 2017 in Italy. A total of 154 MS isolates from different poultry commercial categories (broiler, layer, and turkey sectors) was tested using commercial MIC plates. All MS isolates showed very high MIC values of erythromycin (MIC90 ≥8 µg/mL) and enrofloxacin (MIC90 ≥16 µg/mL). MIC values of doxycycline and oxytetracycline obtained were superimposable to each other with only a one-fold dilution difference. Discrepancies between MIC values of tylosin and tilmicosin were observed. Interestingly, seven isolates showed very high MIC values of lincomycin and tilmicosin, but not all of them showed very high MIC values of tylosin. Most of the MS isolates showed low MIC values of spiramycin, but seven strains showed a MIC ≥16 µg/mL. In the observation period, the frequency of the different MIC classes varied dependently on the tested antibiotic. Interestingly, tilmicosin MICs clearly showed a time-dependent progressive shift towards high-concentration classes, indicative of an on-going selection process among MS isolates. Until standardized breakpoints become available to facilitate data interpretation, it will be fundamental to continue studying MIC value fluctuations in the meantime in order to create a significant database that would facilitate veterinarians in selecting the proper drug for treating this impactful Mycoplasma.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Lectinas/genética , Mycoplasma synoviae/efeitos dos fármacos , Aves Domésticas/microbiologia , Animais , Diterpenos/farmacologia , Doxiciclina/farmacologia , Enrofloxacina/farmacologia , Eritromicina/farmacologia , Itália , Lincomicina/farmacologia , Testes de Sensibilidade Microbiana , Mycoplasma synoviae/genética , Mycoplasma synoviae/isolamento & purificação , Oxitetraciclina/farmacologia , Espiramicina/farmacologia , Tianfenicol/análogos & derivados , Tianfenicol/farmacologia , Tilosina/análogos & derivados , Tilosina/farmacologia
14.
Med Hypotheses ; 133: 109376, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31472369

RESUMO

Congenital toxoplasmosis is caused by in utero infection of the fetus with the intracellular parasite Toxoplasma gondii. Upon infection, the parasite forms life-long cysts in fetal brain and eyes which are resistant to the currently accepted therapy of pyrimethamine and sulfadiazine. These cysts commonly reactivate later in life causing chorioretinitis and visual impairment, and rarely cause neurological complications. I hypothesize that adjunctive, bradyzoite-directed therapies have the potential to alleviate a significant burden of disease by reducing cyst burden in neonatal brain and eyes. Atovaquone is perhaps the most promising drug for further evaluation given its low side-effect profile, established safety, and efficacy in animal models reducing cyst burden. Very limited observational data in humans suggests atovaquone may prevent Toxoplasma-associated chorioretinitis recurrence. Clinical trials are needed to evaluate it and other potential drugs as adjunctive treatment in congenital toxoplasmosis.


Assuntos
Antiprotozoários/uso terapêutico , Coriorretinite/tratamento farmacológico , Toxoplasma/efeitos dos fármacos , Toxoplasmose Cerebral/tratamento farmacológico , Toxoplasmose Ocular/tratamento farmacológico , Animais , Antiprotozoários/farmacologia , Atovaquona/farmacologia , Atovaquona/uso terapêutico , Encéfalo/parasitologia , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Olho/parasitologia , Humanos , Lactente , Recém-Nascido , Camundongos , Modelos Biológicos , Recidiva , Espiramicina/farmacologia , Espiramicina/uso terapêutico , Toxoplasma/crescimento & desenvolvimento , Toxoplasmose Animal/congênito , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Congênita
15.
Med Chem ; 14(6): 604-616, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29332592

RESUMO

BACKGROUND: RNase P-mediated cleavage of target RNAs has been proposed as a promising tool for gene silencing. Ets-2 proto-oncogene controls the expression of a wide variety of genes involved in cancer and immunity. OBJECTIVE: Construction of a functional RNase P-based ribozyme (M1GS303) that targets Ets-2 mRNA. METHODS: The accessible sites for targeting of Ets-2 mRNA were identified by footprinting analysis. M1GS303 ribozyme was constructed by cloning. The activity of the ribozyme in the presence or absence of spiramysin in E. coli cells and human cell lines was quantified by RT-PCR. The efficiency of the ribozyme in silencing the endogenous expression of Ets-2 in human cell lines was examined by RT-PCR, western blot and immunofluorescence analysis. RESULTS: In E. coli cells co-transformed with plasmids bearing M1GS303 and the ets-2 target gene, Ets-2 mRNA was decreased by 93% 12h after IPTG induction in the absence, and after 4h in the presence of spiramycin. Ets-2 was rapidly downregulated in the human embryonic kidney cell line HEK293 and the T-cell line Jurkat transfected with an M1GS303 plasmid; the silencing effect of M1GS303 was considerably faster when the cells were cultured with spiramycin. In Jurkat cells, Ets-2-downregulation resulted in upregulation of the expression of IL-2, IL-4 and IFN-α cytokine genes that have Ets-2 binding sites on their promoters, whereas it had no effect on the expression of the IL-10 gene that lacks Ets-2 binding sites on its promoter. CONCLUSIONS: M1GS303 ribozyme cleaves effectively Ets-2 mRNA in bacteria and mammalian cells, and its activity is enhanced by spiramycin. Downregulation of ets-2 gene in the T-cell line Jurkat upregulates IL-2, IL-4 and IFN-α cytokine genes. M1GS technology may be a better alternative to conventional gene-interference therapies and the delineation of the effects of gene silencing in various pathologies.


Assuntos
Oncogenes/genética , Engenharia de Proteínas , Proteína Proto-Oncogênica c-ets-2/genética , RNA Catalítico/genética , RNA Mensageiro/genética , Regulação para Baixo , Escherichia coli/genética , Células HEK293 , Humanos , Interferon-alfa/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Células Jurkat , Proto-Oncogene Mas , Proteína Proto-Oncogênica c-ets-2/antagonistas & inibidores , Proteína Proto-Oncogênica c-ets-2/metabolismo , Ribonuclease P/genética , Espiramicina/farmacologia , Regulação para Cima
16.
Bioorg Med Chem Lett ; 27(19): 4576-4577, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28867456

RESUMO

The antimicrobial activity of bitespiramycin (BT) against Chlamydia trachomatis (Ct), Chlamydia pneumoniae (Cp), Ureaplasma urealyticum (Uu), and Mycoplasma pneumoniae (Mp), was compared with those of azithromycin (AZM) and acetylspiramycin (AT-SP) in vitro. Furthermore, the anti-Mp activities of BT and AZM were evaluated in a hamster model. The activities of BT in vitro were similar to those of AZM but were more effective than those of AT-SP. BT effectively inhibited Mp infection at a dose of 200mg/kg in a hamster model.


Assuntos
Antibacterianos/farmacologia , Chlamydia trachomatis/efeitos dos fármacos , Chlamydophila pneumoniae/efeitos dos fármacos , Mycoplasma pneumoniae/efeitos dos fármacos , Espiramicina/análogos & derivados , Ureaplasma urealyticum/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Espiramicina/síntese química , Espiramicina/química , Espiramicina/farmacologia , Relação Estrutura-Atividade
17.
Exp Parasitol ; 181: 111-118, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28803905

RESUMO

Trophoblast infection by Toxoplasma gondii plays a pivotal role in the vertical transmission of toxoplasmosis. Here, we investigate whether the antibiotic therapy with azithromycin, spiramycin and sulfadiazine/pyrimethamine are effective to control trophoblast infection by two Brazilian T. gondii genotypes, TgChBrUD1 or TgChBrUD2. Two antibiotic protocols were evaluated, as follow: i) pre-treatment of T. gondii-tachyzoites with selected antibiotics prior trophoblast infection and ii) post-treatment of infected trophoblasts. The infection index/replication and the impact of the antibiotic therapy on the cytokine milieu were characterized. It was observed that TgChBrUD2 infection induced lower infection index/replication as compared to TgChBrUD1. Regardless the therapeutic protocol, azithromycin was more effective to control the trophoblast infection with both genotypes when compared to conventional antibiotics. Azithromycin induced higher IL-12 production in TgChBrUD1-infected cells that may synergize the anti-parasitic effect. In contrast, the effectiveness of azithromycin to control the TgChBrUD2-infection was not associated with the IL-12 production. BeWo-trophoblasts display distinct susceptibility to T. gondii genotypes and the azithromycin treatment showed to be more effective than conventional antibiotics to control the T. gondii infection/replication regardless the parasite genotype.


Assuntos
Antiprotozoários/farmacologia , Azitromicina/farmacologia , Toxoplasma/efeitos dos fármacos , Trofoblastos/parasitologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Combinação de Medicamentos , Genótipo , Humanos , Interleucina-12/metabolismo , Pirimetamina/farmacologia , Espiramicina/farmacologia , Sulfadiazina/farmacologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Trofoblastos/efeitos dos fármacos
18.
Biomedica ; 37(0): 86-91, 2017 Apr 01.
Artigo em Espanhol | MEDLINE | ID: mdl-28527270

RESUMO

INTRODUCTION: Gestational toxoplasmosis is frequent and severe. There is still debate about the benefits of treatment against ocular manifestations in the newborn. Spiramycin treatment is used for this purpose, unfortunately prenatal diagnosis is sometimes delayed and pregnant women are not treated. OBJECTIVE: To describe the relationship between treatment with spiramycin during pregnancy in mothers with gestational toxoplasmosis and development of ocular toxoplasmosis in newborns. MATERIALS AND METHODS: We conducted a descriptive study of a case series. We evaluated a prospective cohort of patients diagnosed with gestational toxoplasmosis during three years at the Retinology Service at the Clínica Universitaria Bolivariana in Medellín. RESULTS: Gestational toxoplasmosis was found in 23 mothers; 15 (65%) were treated during pregnancy with 3 g per day of spiramycin, eight (35%) patients were untreated. In the treated group just one newborn developed ocular toxoplasmosis (6.6%), in contrast with five (62.5%) of the eight patients who did not receive treatment. These results suggest that pregnancy treatment reduces the relative risk of ocular toxoplasmosis in the newborn by 96% (95% CI: 33 - 100%). Only two (14%) of the patients who were evaluated, had nervous system involvement related to toxoplasmosis in CT scan or cerebral ultrasound. These two patients also developed ocular pathology and were diagnosed at the time of birth, so they did not received antenatal treatment. CONCLUSIONS: A protective effect was found against the ocular involvement in patients whose mother received treatment with spiramycin (OR=0.04;95% CI: 0.00-0.67), p<0.01 (Fisher's Exact Test).


Assuntos
Espiramicina/farmacologia , Toxoplasmose Congênita/tratamento farmacológico , Toxoplasmose/epidemiologia , Colômbia , Feminino , Humanos , Recém-Nascido , Gravidez , Diagnóstico Pré-Natal , Estudos Prospectivos , Espiramicina/química , Toxoplasmose/genética , Toxoplasmose/prevenção & controle , Toxoplasmose/terapia , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/epidemiologia , Toxoplasmose Congênita/prevenção & controle
19.
Environ Geochem Health ; 39(6): 1595-1605, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28551881

RESUMO

The occurrence of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs) has been intensively investigated for wastewater treatment systems treating single class of antibiotic in recent years. However, the impacts of alternately occurring antibiotics in antibiotic production wastewater on the behavior of ARGs in biological treatment systems were not well understood yet. Herein, techniques including high-capacity quantitative PCR and quantitative PCR (qPCR) were used to investigate the behavior of ARGs in an anaerobic-aerobic full-scale system. The system alternately treated three kinds of antibiotic production wastewater including ribostamycin, spiramycin and paromomycin, which referred to stages 1, 2 and 3. The aminoglycoside ARGs (52.1-79.3%) determined using high-capacity quantitative PCR were the most abundant species in all sludge samples of the three stages. The total relative abundances of macrolide-lincosamide-streptogramin (MLS) resistance genes and aminoglycoside resistance genes measured using qPCR were significantly higher (P < 0.05) in aerobic sludge than in sewage sludge. However, the comparison of ARGs acquired from three alternate stages revealed that MLS genes and the aminoglycoside ARGs did not vary significantly (P > 0.05) in both aerobic and anaerobic sludge samples. In aerobic sludge, one acetyltransferase gene (aacA4) and the other three nucleotidyltransferase genes (aadB, aadA and aadE) exhibited positive correlations with intI1 (r 2 = 0.83-0.94; P < 0.05), implying the significance of horizontal transfer in their proliferation. These results and facts will be helpful to understand the abundance and distribution of ARGs from antibiotic production wastewater treatment systems.


Assuntos
Resistência Microbiana a Medicamentos/genética , Paromomicina/química , Ribostamicina/química , Espiramicina/química , Águas Residuárias/química , Aerobiose , Anaerobiose , Bactérias/efeitos dos fármacos , Bactérias/genética , Transferência Genética Horizontal , Mutação , Paromomicina/farmacologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Ribostamicina/farmacologia , Esgotos , Espiramicina/farmacologia
20.
Biomédica (Bogotá) ; 37(supl.1): 86-91, abr. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-888514

RESUMO

Resumen Introducción. La toxoplasmosis de la gestación es frecuente y grave. Hasta ahora no hay consenso sobre la utilidad del tratamiento para prevenir complicaciones oculares en el neonato. En la actualidad, uno de los medicamentos utilizados en las madres diagnosticadas es la espiramicina oral. Infortunadamente, en algunas mujeres gestantes no se hace el diagnóstico prenatal y, por esta u otras razones, no reciben el tratamiento. Objetivo. Describir la relación entre el tratamiento con espiramicina durante el embarazo en madres con toxoplasmosis de la gestación y la presentación de toxoplasmosis ocular en los recién nacidos. Materiales y métodos. Se llevó a cabo un estudio observacional descriptivo de serie de casos. Se evaluó una serie prospectiva de pacientes con toxoplasmosis de la gestación durante tres años de seguimiento en el Servicio de Retinología de la Clínica Universitaria Bolivariana de Medellín. Resultados. Se registraron 23 madres con diagnóstico de toxoplasmosis de la gestación. Quince de ellas (65 %) recibieron durante la gestación tratamiento con espiramicina en dosis de 3 g al día; uno de los neonatos (6,6 %) presentó toxoplasmosis ocular. De las ocho (35 %) pacientes que no recibieron tratamiento, cinco (62,5 %) tuvieron hijos con compromiso ocular por toxoplasma. La razón de momios (odds ratio, OR) del efecto protector contra dicho compromiso en los pacientes cuyas madres recibieron tratamiento fue de 0,04 (IC95% 0,00-0,67), con valor de p menor de 0,01 en la prueba exacta de Fisher. Solo se evidenció compromiso del sistema nervioso central por toxoplasmosis mediante las imágenes de tomografía o ecografía cerebral en dos (14 %) pacientes de las 14 en quienes se hicieron estos estudios. Los dos pacientes presentaron, además, compromiso ocular; ambos fueron diagnosticados en el momento del nacimiento y sus madres no habían recibido tratamiento prenatal. Conclusiones. Estos resultados evidencian que el tratamiento con espiramicina durante el embarazo en la toxoplasmosis de la gestación redujo en 96 % (IC95% 33-100 %) el riesgo relativo de presentar la enfermedad en el recién nacido.


Abstrat Introduction: Gestational toxoplasmosis is frequent and severe. There is still debate about the benefits of treatment against ocular manifestations in the newborn. Spiramycin treatment is used for this purpose, unfortunately prenatal diagnosis is sometimes delayed and pregnant women are not treated. Objective: To describe the relationship between treatment with spiramycin during pregnancy in mothers with gestational toxoplasmosis and development of ocular toxoplasmosis in newborns. Materials and methods: We conducted a descriptive study of a case series. We evaluated a prospective cohort of patients diagnosed with gestational toxoplasmosis during three years at the Retinology Service at the Clínica Universitaria Bolivariana in Medellín. Results: Gestational toxoplasmosis was found in 23 mothers; 15 (65%) were treated during pregnancy with 3 g per day of spiramycin, eight (35%) patients were untreated. In the treated group just one newborn developed ocular toxoplasmosis (6.6%), in contrast with five (62.5%) of the eight patients who did not receive treatment. These results suggest that pregnancy treatment reduces the relative risk of ocular toxoplasmosis in the newborn by 96% (95% CI: 33 - 100%). Only two (14%) of the patients who were evaluated, had nervous system involvement related to toxoplasmosis in CT scan or cerebral ultrasound. These two patients also developed ocular pathology and were diagnosed at the time of birth, so they did not received antenatal treatment. Conclusions: A protective effect was found against the ocular involvement in patients whose mother received treatment with spiramycin (OR=0.04;95% CI: 0.00-0.67), p<0.01 (Fisher's Exact Test).


Assuntos
Feminino , Humanos , Recém-Nascido , Gravidez , Espiramicina/farmacologia , Toxoplasmose/epidemiologia , Toxoplasmose Congênita/tratamento farmacológico , Diagnóstico Pré-Natal , Espiramicina/química , Toxoplasmose/genética , Toxoplasmose/prevenção & controle , Toxoplasmose/terapia , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/prevenção & controle , Toxoplasmose Congênita/epidemiologia , Estudos Prospectivos , Colômbia
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