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1.
Mikrochim Acta ; 191(1): 34, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108923

RESUMO

Magnetic solid phase extraction with the functionalization of protein onto micro- or nano-particles as a probe is favorable for the discovery of new drugs from complicated natural products. Herein, we aimed to develop a rapid method by immobilizing halogenated alkane dehalogenase (Halo)-tagged calcium-sensing receptor (CaSR) directly out of crude cell lysates onto the surface of magnetic microspheres (MM) with no need to purify protein. Thereby we achieved CaSR-functionalized MM for revealing adsorption characteristics of agonist neomycin and screening ligands from herbal medicine Radix Astragali (RA). About 43.87 mg CaSR could be immobilized per 1 g MM within 30 min, and the acquired CaSR-functionalized MM showed good stability and activity for 4 weeks. The maximum adsorption capacity of neomycin on CaSR-functionalized MM was determined as 4.70 × 10-4 ~ 3.96 × 10-4 mol/g within 277 ~ 310 K, and its adsorption isotherm characteristics described best by the Temkin model were further validated using isothermal titration calorimetry. It was inferred that CaSR's affinity for neomycin was driven by electrostatic forces in a spontaneous process when the system reached an equilibrium state. Moreover, the ligands from the RA extract were screened, three of which were assigned as astragaloside IV, ononin, and calycosin based on HPLC-MS. Our findings demonstrated that the functionalization of a receptor onto magnetic materials designed as an affinity probe has the capability to recognize its agonist and capture the ligands selectively from complex matrices like herbs.


Assuntos
Neomicina , Receptores de Detecção de Cálcio , Microesferas , Adsorção , Ligantes , Fenômenos Magnéticos
2.
Aust Vet J ; 101(3): 115-120, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36433648

RESUMO

Corneal ulceration is a common ophthalmic condition in horses. It is frequently caused by trauma to the corneal surface, followed by secondary infection by commensal or pathogenic organisms including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Staphylococcus spp. Emerging antimicrobial resistance amongst these organisms has raised the need for appropriate antimicrobial therapy selection, to optimise treatment efficacy while minimising further antimicrobial resistance. Medical records of 38 horses presented at the University Veterinary Teaching Hospital Camden for ulcerative keratitis between 2010 and 2020 were reviewed to identify those with positive bacterial cultures and antimicrobial susceptibility profiles (13/38). Common susceptibility patterns were identified and used to guide the empirical treatment of equine bacterial corneal ulcers. Pseudomonas spp. (64.3%), Streptococcus equi subspecies zooepidemicus (14.3%) and Actinobacillus spp. (14.3%) were most commonly identified. Susceptibility to amikacin, gentamicin and ciprofloxacin was observed in 100%, 66.7% and 85.7% Pseudomonas spp. isolates respectively. Resistance to polymyxin B and neomycin occurred in 85.7% and 71.4% of Pseudomonas spp., respectively. All Streptococcus equi subspecies zooepidemicus organisms in this study were susceptible to ceftiofur, cephalexin, penicillin and ampicillin, while they were all resistant to gentamicin, neomycin, enrofloxacin and marbofloxacin. Predominating in this study, Pseudomonas spp. maintained overall aminoglycoside susceptibility despite some emerging resistance, and good fluoroquinolone susceptibility. High resistance to Polymyxin B could have arisen from its common use as first-line therapy for bacterial corneal ulcers. Although further research is required, these new findings about predominant bacteria in equine corneal ulceration in the Camden region and their antimicrobial susceptibility patterns can be used to guide the empirical treatment of bacterial corneal ulcers in horses.


Assuntos
Anti-Infecciosos , Úlcera da Córnea , Infecções Oculares Bacterianas , Doenças dos Cavalos , Ceratite , Streptococcus equi , Cavalos , Animais , Úlcera da Córnea/tratamento farmacológico , Úlcera da Córnea/veterinária , Polimixina B , Hospitais Veterinários , Úlcera/tratamento farmacológico , Úlcera/veterinária , Universidades , Hospitais de Ensino , Ceratite/tratamento farmacológico , Ceratite/microbiologia , Ceratite/veterinária , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/microbiologia , Infecções Oculares Bacterianas/veterinária , Gentamicinas , Testes de Sensibilidade Microbiana/veterinária , Neomicina , Farmacorresistência Bacteriana , Estudos Retrospectivos , Doenças dos Cavalos/tratamento farmacológico
3.
Drug Deliv ; 29(1): 3370-3383, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36404771

RESUMO

Diabetes mellitus is one of the most concerning conditions, and its chronic consequences are almost always accompanied by infection, oxidative stress, and inflammation. Reducing excessive reactive oxygen species and the wound's inflammatory response is a necessary treatment during the acute inflammatory phase of diabetic wound healing. Malva sylvestris extract (MS) containing nanofibers containing neomycin sulfate (NS) were synthesized for this investigation, and their impact on the healing process of diabetic wounds was assessed. Using Design Expert, the electrospinning process for the fabrication of NS nanofibers (NS-NF) was adjusted for applied voltage (X1), the distance between the needle's tip and the collector (X2), and the feed rate (X3) for attaining desired entrapment efficacy [EE] and average nanofiber diameter (ND). The optimal formulation can be prepared with 19.11 kV of voltage, 20 cm of distance, and a flow rate of 0.502 mL/h utilizing the desirability approach. All the selected parameters and responses have their impact on drug delivery from nanofibers. In addition, M. sylvestris extracts have been added into the optimal formulation [MS-NS-NF] and assessed for their surface morphology, tensile strength, water absorption potential, and in vitro drug release studies. The NS and MS delivery from MS-NS-NF has been extended for more than 60 h. M. sylvestris-loaded nanofibers demonstrated superior antibacterial activity compared to plain NS nanofibers. The scaffolds featured a broad aspect and a highly linked porous fibrous network structure. Histomorphometry study and the in vitro scratch assay demonstrate the formulation's efficacy in treating diabetic wound healing. The cells treated with MS-NS-NF in vivo demonstrated that wound dressings successfully reduced both acute and chronic inflammations. To improve the healing of diabetic wounds, MS-NS-NF may be regarded as an appropriate candidate for wound dressing.


Assuntos
Diabetes Mellitus , Malva , Nanofibras , Nanofibras/química , Neomicina , Cicatrização , Extratos Vegetais/farmacologia , Extratos Vegetais/química
4.
Front Cell Infect Microbiol ; 12: 838340, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811665

RESUMO

Impaired intestinal barrier function and gut microbiota dysbiosis are believed to be related to exacerbation of acute pancreatitis (AP). As a bacterial cell wall peptidoglycan component, diaminopimelic acid (DAP) is a specific ligand of NOD1 that regulates the NOD1/RIP2/NF-kB signaling pathway. Here, we investigated the role of DAP in the crosstalk between the gut microbiota and pancreas during the occurrence of AP. Upregulation of NOD1/RIP2/NF-kB and elevated serum DAP levels were found in severe AP (SAP) model rats. The accumulation of DAP in SAP patients corroborated its ability to serve as an indicator of disease severity. Subsequently, SAP rats were treated with oral administration of the traditional Chinese medicine Qingyi Keli (QYKL) as well as neomycin, which can widely eliminate DAP-containing bacteria. Both QYKL and neomycin intervention ameliorated intestinal and pancreatic damage and systemic inflammation in SAP rats. Through 16S rDNA sequencing, we found that QYKL could rehabilitate the gut microbiota structure and selectively inhibit the overgrowth of enteric bacteria, such as Helicobacter and Lactobacillus, in SAP rats without affecting some protective strains, including Romboutsia and Allobaculum. Interestingly, we demonstrated that the decrease in serum DAP was accompanied by suppression of the NOD1/RIP2/NF-kB signaling pathway in both the intestine and pancreas of the two intervention groups. Taken together, these results suggested that the gut microbiota-DAP-NOD1/RIP2 signaling pathway might play a critical role in the progression of AP and that SAP could be alleviated via intervention in the signaling pathway. Our work provides new potential early warning indicators of SAP and targets for intervention.


Assuntos
Microbioma Gastrointestinal , Pancreatite , Doença Aguda , Animais , Ácido Diaminopimélico/química , Ácido Diaminopimélico/metabolismo , Ácido Diaminopimélico/farmacologia , Microbioma Gastrointestinal/fisiologia , NF-kappa B/metabolismo , Neomicina , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD1/metabolismo , Ratos , Transdução de Sinais
5.
JCI Insight ; 6(7)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33735112

RESUMO

To identify small molecules that shield mammalian sensory hair cells from the ototoxic side effects of aminoglycoside antibiotics, 10,240 compounds were initially screened in zebrafish larvae, selecting for those that protected lateral-line hair cells against neomycin and gentamicin. When the 64 hits from this screen were retested in mouse cochlear cultures, 8 protected outer hair cells (OHCs) from gentamicin in vitro without causing hair-bundle damage. These 8 hits shared structural features and blocked, to varying degrees, the OHC's mechano-electrical transducer (MET) channel, a route of aminoglycoside entry into hair cells. Further characterization of one of the strongest MET channel blockers, UoS-7692, revealed it additionally protected against kanamycin and tobramycin and did not abrogate the bactericidal activity of gentamicin. UoS-7692 behaved, like the aminoglycosides, as a permeant blocker of the MET channel; significantly reduced gentamicin-Texas red loading into OHCs; and preserved lateral-line function in neomycin-treated zebrafish. Transtympanic injection of UoS-7692 protected mouse OHCs from furosemide/kanamycin exposure in vivo and partially preserved hearing. The results confirmed the hair-cell MET channel as a viable target for the identification of compounds that protect the cochlea from aminoglycosides and provide a series of hit compounds that will inform the design of future otoprotectants.


Assuntos
Aminoglicosídeos/efeitos adversos , Cóclea/efeitos dos fármacos , Ototoxicidade/prevenção & controle , Animais , Cóclea/citologia , Avaliação Pré-Clínica de Medicamentos/métodos , Embrião não Mamífero/efeitos dos fármacos , Feminino , Gentamicinas/efeitos adversos , Gentamicinas/farmacologia , Células Ciliadas Auditivas/efeitos dos fármacos , Masculino , Mecanotransdução Celular/efeitos dos fármacos , Camundongos Endogâmicos , Testes de Sensibilidade Microbiana , Fator de Transcrição Associado à Microftalmia/genética , Neomicina/efeitos adversos , Técnicas de Cultura de Órgãos , Ototoxicidade/etiologia , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/farmacologia , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
6.
PLoS One ; 15(10): e0240480, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33079945

RESUMO

Global amphibian populations are being decimated by chytridiomycosis, a deadly skin infection caused by the fungal pathogens Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal). Although ongoing efforts are attempting to limit the spread of these infections, targeted treatments are necessary to manage the disease. Currently, no tools for genetic manipulation are available to identify and test specific drug targets in these fungi. To facilitate the development of genetic tools in Bd and Bsal, we have tested five commonly used antibiotics with available resistance genes: Hygromycin, Blasticidin, Puromycin, Zeocin, and Neomycin. We have identified effective concentrations of each for selection in both liquid culture and on solid media. These concentrations are within the range of concentrations used for selecting genetically modified cells from a variety of other eukaryotic species.


Assuntos
Anfíbios/microbiologia , Antifúngicos/farmacologia , Batrachochytrium/efeitos dos fármacos , Batrachochytrium/crescimento & desenvolvimento , Micologia/métodos , Animais , Batrachochytrium/genética , Bleomicina/farmacologia , Cinamatos/farmacologia , Testes Diagnósticos de Rotina , Avaliação Pré-Clínica de Medicamentos , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Testes de Sensibilidade Microbiana , Neomicina/farmacologia , Puromicina/farmacologia , Pirrolidinonas/farmacologia , Seleção Genética
7.
Mol Nutr Food Res ; 64(17): e2000532, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32729948

RESUMO

SCOPE: Soy protein is a high-quality protein and its consumption has been associated with a reduction of serum cholesterol and triglycerides and an improvement in insulin resistance. However, it is not known whether the effects of soy protein are mediated by the gut microbiota. Thus, the aim of this study is to assess whether using antibiotics to partially eradicate the gut microbiota can prevent the beneficial effects of soy protein in rats. METHODS AND RESULTS: Thus, rats are fed one of the following diets for 16 weeks: casein control, soy protein control, high-fat casein, and high-fat soy protein. The rats are then treated for 4 weeks with antibiotics. Body weight and composition, energy expenditure, glucose tolerance test, metabolic endotoxemia, and gut microbiota are measured before and after treatment with antibiotic. The results show that soy protein consumption decreases weight gain, body fat, metabolic endotoxemia, and increases energy expenditure and glucose tolerance. Antibiotic treatment suppresses all these metabolic effects. These changes are accompanied by modifying the diversity and taxonomy of the gut microbiota. CONCLUSION: In conclusion, the evidence suggests that the health benefits of soy protein are partly dependent of the gut microbiota.


Assuntos
Antibacterianos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Proteínas de Soja/farmacologia , Tecido Adiposo/efeitos dos fármacos , Ampicilina/efeitos adversos , Ampicilina/farmacologia , Animais , Antibacterianos/efeitos adversos , Biomarcadores/metabolismo , Composição Corporal/efeitos dos fármacos , Caseínas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Endotoxemia/induzido quimicamente , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/fisiologia , Inflamação/genética , Inflamação/metabolismo , Masculino , Neomicina/efeitos adversos , Neomicina/farmacologia , Ratos Wistar , Aumento de Peso/efeitos dos fármacos
8.
N Z Vet J ; 68(2): 126-133, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31608795

RESUMO

Case history: Gradual onset of ocular opacity was observed in three gold-striped geckos (Woodworthia chrysosiretica), and five Pacific geckos (Dactylocnemis pacificus) held in two adjacent terrariums in a zoological institution located in the North Island of New Zealand. Ultraviolet light and heat had been provided for the previous 3-4 years by a fluorescent bulb, but in the last 4 weeks of winter a ceramic heat bulb had been added, situated 10 cm above the upper mesh of the cageClinical findings: All eight geckos presented with mostly bilateral lesions of varying severity confined to the central or upper quadrant of the spectacles. These lesions ranged from variable areas of opacity within the stroma of the spectacle to similarly distributed ulcers of the surface epithelium of both spectacles. The spectacle lesions in the Pacific geckos responded well to treatment with topical combined antimicrobial therapy, within 18-29 days. The gold-striped geckos suffered complications including dysecdysis, severe spectacle ulceration and perforation, mycotic spectaculitis, and widespread mycotic dermatitis resulting in death or leading to euthanasia.Pathological findings: In the three gold-striped geckos, there were extensive areas of deep ulceration and replacement of the spectacle with a thick serocellular crust containing large numbers of fungal elements. The affected areas of the stroma were expanded by large deposits of proteinaceous and mucinous material, pyknotic cellular debris and moderate numbers of heterophils and macrophages as well as infiltrating fungal hyphae.Diagnosis: Mycotic spectaculitis with ulceration and perforation, and disseminated mycotic dermatitis likely secondary to thermal burns.Clinical relevance: This is the first report of thermal burns of the spectacle in any reptile. There was species variation in the burn severity with gold-striped geckos showing more severe lesions, possibly due to a mix of behavioural and anatomical factors. The thermal burns to the spectacles in three cases were complicated by delayed healing, perforation, dysecdysis and severe mycotic infection.


Assuntos
Queimaduras/veterinária , Oftalmopatias/veterinária , Calefação/instrumentação , Abrigo para Animais , Lagartos , Animais , Animais de Zoológico , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Bacitracina/administração & dosagem , Bacitracina/uso terapêutico , Queimaduras/etiologia , Combinação de Medicamentos , Oftalmopatias/etiologia , Oftalmopatias/patologia , Meloxicam/uso terapêutico , Neomicina/administração & dosagem , Neomicina/uso terapêutico , Polimixina B/administração & dosagem , Polimixina B/uso terapêutico , Raios Ultravioleta
9.
BMC Res Notes ; 12(1): 369, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262338

RESUMO

OBJECTIVES: Consumption of fish/seafood is clearly linked to higher mercury levels in human tissue samples. However, correlations between methylmercury (MeHg) intakes calculated from dietary surveys and mercury body burdens are usually weak and can vary across populations. Different factors may affect MeHg absorption, distribution, metabolism and excretion, including co-exposures to phytochemicals and antibiotics, which were shown to affect mercury body burdens in rodents. Based on the observation that rat pups developmentally exposed to MeHg and a Rhododendron tomentosum extract (Labrador Tea) presented significantly higher blood mercury levels at weaning compared to pups exposed to MeHg alone, the modulation of MeHg toxicokinetics by Labrador Tea was further investigated in adult rats. RESULTS: Total mercury levels were quantified in the blood, liver, kidney and feces of adult male rats exposed to MeHg (1.2 mg/kg bodyweight/day, for 3 weeks) administered either alone or in combination with Labrador Tea (100 mg/kg bodyweight/day) or with an antibiotics cocktail (to inhibit MeHg demethylation by gut bacteria). While the reduced fecal excretion and higher blood mercury levels expected from antibiotics-treated rats were observed, mercury levels in samples from Labrador Tea-treated rats were not significantly different from those measured in samples from rats exposed to MeHg alone.


Assuntos
Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Compostos de Metilmercúrio/farmacocinética , Extratos Vegetais/farmacocinética , Rhododendron/química , Animais , Antibacterianos/administração & dosagem , Transporte Biológico/efeitos dos fármacos , Fezes/química , Rim/química , Rim/metabolismo , Ledum/química , Fígado/química , Fígado/metabolismo , Masculino , Neomicina/administração & dosagem , Penicilinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Estreptomicina/administração & dosagem
10.
Int Ophthalmol ; 39(6): 1355-1366, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29922978

RESUMO

PURPOSE: Conventional dosage form like eye drops showed poor therapeutic response and also require frequent dosing. Therefore, developing the dosage form to deliver the drug to the target site without much loss of drug or without causing any systemic side effects is the challenging job for the researchers in pharmaceutical industries. OBJECTIVE: The main aim of the present work was to formulate and evaluate hydrogel-based drug delivery containing combination of neomycin sulphate and betamethasone sodium phosphate in order to provide prolonged release and also better bioavailability of drugs for the treatment of eye infections. METHODS: In this study, poloxamer 407 and chitosan at different concentrations were used as the gelling agents. The prepared formulations were evaluated for clarity, pH, drug content, gelling capacity, gelling temperature and in vitro drug release study. RESULTS: From the preliminary studies, F5 formulation was selected as an optimized formulation. The optimized formulation was further evaluated for ex vivo permeation study, sterility test, HET-CAM and ocular irritation testing using rabbits. Ocular irritation by HET-CAM assay showed that the formulated gel does not cause any irritation to the blood vessels. Draize irritation test was performed using rabbits and results showed that formulation was non-irritant to the eye. CONCLUSION: The formulated hydrogel formulation can be used as an alternative to conventional ophthalmic eye drop formulation of drugs neomycin and betamethasone for the purpose of providing prolonged therapy for the treatment of conjunctivitis.


Assuntos
Antibacterianos/administração & dosagem , Betametasona/análogos & derivados , Conjuntivite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Glucocorticoides/administração & dosagem , Hidrogéis/química , Neomicina/administração & dosagem , Animais , Antibacterianos/farmacocinética , Betametasona/administração & dosagem , Betametasona/farmacocinética , Disponibilidade Biológica , Quitosana/química , Modelos Animais de Doenças , Infecções Oculares/tratamento farmacológico , Glucocorticoides/farmacocinética , Neomicina/farmacocinética , Poloxâmero/química , Coelhos
11.
J Anim Physiol Anim Nutr (Berl) ; 103(1): 72-86, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30485573

RESUMO

The purpose of this study was to verify the ability of a probiotic in the feed to maintain the stability of the gut microbiota in chickens after antibiotic therapy and its association with growth performance. One thousand six hundred twenty 1-day-old Cobb male were housed in floor pens (36 pens, 45 birds/pen) and were fed corn-/soya bean meal-based diets supplemented with or without probiotic (Bacillus subtilis) during the entire rearing phase. From 21 to 24 days of age (three consecutive days), the chickens were submitted to antibiotic therapy via drinking water (bacitracin and neomycin) in order to mimic a field treatment and induce dysbiosis. Growth performance was monitored until 42 days of age. At 2, 4 and 6 days after antibiotic therapy, three chickens from each pen were euthanized and the contents of the small intestine and caeca were collected and pooled. The trial was conducted with four treatments and nine replicates in a 2 × 2 factorial arrangement for performance characteristics (with and without probiotic × with and without antibiotic therapy); for the intestinal microbiota, it was in a 2 × 2 × 3 factorial arrangement (with and without probiotic × with and without antibiotic therapy × 2, 4 and 6 days after the antibiotic therapy) with three replicates per treatment. Terminal restriction length polymorphism (T-RFLP) analysis showed that the structure of gut bacterial community was shaped by the intestinal segment and by the time after the antibiotic therapy. The number of 16S rDNAs copies in caecum contents decreased with time after the therapeutic treatment. The antibiotic therapy and dietary probiotic supplementation decreased richness and diversity indexes in the caecal contents. The improved performance observed in birds supplemented with probiotic may be related to changes promoted by the feed additive in the structure of the intestinal bacterial communities and phylogenetic groups. Antibiotic therapy modified the bacterial structure, but did not cause loss of broiler performance.


Assuntos
Ração Animal/análise , Bacitracina/farmacologia , Galinhas/crescimento & desenvolvimento , Microbioma Gastrointestinal/efeitos dos fármacos , Neomicina/farmacologia , Probióticos/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Bacitracina/administração & dosagem , Galinhas/microbiologia , Dieta/veterinária , Neomicina/administração & dosagem , Distribuição Aleatória
12.
Methods ; 156: 110-120, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391513

RESUMO

Among different RNA modifications, the helix 69 (H69) region of the bacterial ribosomal RNA (rRNA) contains three pseudouridines (Ψs). H69 is functionally important due to its location in the heart of the ribosome. Several structural and functional studies have shown the importance of Ψ modifications in influencing the H69 conformation as well as maintaining key interactions in the ribosome during protein synthesis. Therefore, a need exists to understand the influence of modified nucleosides on conformational dynamics of the ribosome under solution conditions that mimic the cellular environment. In this review on chemical probing, we provide detailed protocols for the use of dimethyl sulfate (DMS) to examine H69 conformational states and the influence of Ψ modifications under varying solution conditions in the context of both ribosomal subunits and full ribosomes. The use of DMS footprinting to study the binding of aminoglycosides to the H69 region of bacterial rRNA as a potential antibiotic target will also be discussed. As highlighted in this work, DMS probing and footprinting are versatile techniques that can be used to gain important insight into RNA local structure and RNA-ligand interactions, respectively.


Assuntos
Escherichia coli/genética , Impressão Molecular/métodos , Pseudouridina/química , RNA Ribossômico 16S/química , RNA Ribossômico 23S/química , Compostos de Anilina/química , Antibacterianos/farmacologia , Fracionamento Celular/métodos , DNA Complementar/biossíntese , DNA Complementar/química , DNA Complementar/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Gentamicinas/farmacologia , Hidroliases/genética , Hidroliases/metabolismo , Ligantes , Cloreto de Magnésio/farmacologia , Neomicina/farmacologia , Conformação de Ácido Nucleico , Fatores de Terminação de Peptídeos/genética , Fatores de Terminação de Peptídeos/metabolismo , Pseudouridina/genética , Pseudouridina/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , RNA Ribossômico 23S/genética , RNA Ribossômico 23S/metabolismo , Transcrição Reversa , Subunidades Ribossômicas Maiores de Bactérias/química , Subunidades Ribossômicas Maiores de Bactérias/efeitos dos fármacos , Subunidades Ribossômicas Maiores de Bactérias/genética , Subunidades Ribossômicas Maiores de Bactérias/metabolismo , Subunidades Ribossômicas Menores de Bactérias/química , Subunidades Ribossômicas Menores de Bactérias/efeitos dos fármacos , Subunidades Ribossômicas Menores de Bactérias/genética , Subunidades Ribossômicas Menores de Bactérias/metabolismo , Ribossomos/química , Ribossomos/efeitos dos fármacos , Ribossomos/genética , Ribossomos/metabolismo , Ésteres do Ácido Sulfúrico/química
13.
J Pharm Biomed Anal ; 164: 630-635, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30471635

RESUMO

This work proposes a new method for the in vitro evaluation of the effect of UV irradiation on the production of free radicals and other reactive species during the photodecomposition of drugs. The method was based on the UV irradiation of antibiotics molecules to generate excited states that undergo to homolytic bond cleavages. These reactive species can be detected by their ability to oxidize the luminol, producing the electronically excited aminophtalate, which decays to the ground state releasing electromagnetic radiation in the visible zone of the spectrum. This method was applied to penicillin G, nafcillin, azlocillin and neomycin dissolved in water. It was found that the intensity of the luminol chemiluminescence emission (CL) was proportional to the concentration and dependent on the molecular structure of these drugs. Under the optimized conditions, it was found that penicillin and azlocillin were the most susceptible to photodegradation, while neomycin sulfate was the less affected by the UV light. It was observed that the addition to the antibiotics dissolutions of a hydro-alcoholic extract of petals of calyxes of Roselle reduced the CL intensity, indicating that the extract was able to scavenge the free radicals in the irradiated drugs. This result suggest that its addition to the antibiotics can help in the protection against the radicals formed during the exposition to solar light of patients treated with topic similar antibiotics.


Assuntos
Antibacterianos/efeitos da radiação , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/antagonistas & inibidores , Hibiscus/química , Medições Luminescentes/métodos , Extratos Vegetais/farmacologia , Administração Tópica , Antibacterianos/administração & dosagem , Antibacterianos/química , Azlocilina/administração & dosagem , Azlocilina/química , Azlocilina/efeitos da radiação , Dermatite Fototóxica/etiologia , Dermatite Fototóxica/prevenção & controle , Flores/química , Radicais Livres/química , Radicais Livres/toxicidade , Substâncias Luminescentes/química , Luminol/química , Neomicina/administração & dosagem , Neomicina/química , Neomicina/efeitos da radiação , Oxirredução , Penicilinas/administração & dosagem , Penicilinas/química , Penicilinas/efeitos da radiação , Luz Solar/efeitos adversos , Raios Ultravioleta/efeitos adversos
14.
Lett Appl Microbiol ; 67(2): 175-182, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29763981

RESUMO

Multidrug-resistant bacteria have become common all over the world, necessitating the development of new therapeutic strategies. Synergistic interactions between conventional antibiotics and natural bioactive may have therapeutic benefits in a clinical setting. There are plenty of medicinal plants that have proven efficacy against broad spectrum of micro-organisms. The aim of the work was to assess the antibacterial activity of Cladanthus arabicus, a Moroccan medicinal plant, and Bubonium imbricatum, a Moroccan endemic plant. The evaluation of the synergistic effect of extracted essential oils (EOs) together with some conventional antibiotics was also investigated. Checkerboard test was used to evaluate the interaction of EOs in combination with amoxicillin and neomycin. The results showed that EOs contain a potent activity against the tested Enterobacteriaceae isolates, with inhibition zones values in the range of 8·05 ± 0·1 and 13·1 ± 0·11 mm and MIC values between 200 µg ml-1 to 800 µg ml-1 for C. arabicus and from 400 µg ml-1 to 1600 µg ml-1 for B. imbricatum, respectively. Moreover, the current study allowed concluding that both EOs showed not only satisfactory antibacterial properties but also active effects combined with conventional antibiotics demonstrated by the Fractional Inhibitory Concentration Index (FICI). These findings are very interesting since there are no previous studies on synergistic interactions of these two plants with antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: The development of antibiotic resistance is multifactorial, including the specific nature of the relationship of bacteria to antibiotics. This situation has forced scientists to search for new antimicrobial substances from various sources as novel antimicrobial chemotherapeutic agents. Recently, medicinal plants and their derivatives (essential oils, extracts) have become very important in therapeutics because they encounter minimal challenges of the emergence of resistance. In this direction, the antimicrobial activity of the endemic Bubonium imbricatum plant and medicinal Cladanthus arabicus plant essential oils against multidrug-resistant Enterobacteriaceae strains was demonstrated.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Asteraceae/química , Enterobacteriaceae/crescimento & desenvolvimento , Neomicina/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Enterobacteriaceae/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
15.
JCI Insight ; 3(4)2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29467322

RESUMO

Adoptive T cell therapy (ACT) is a promising new modality for malignancies. Here, we report that adoptive T cell efficacy in tumor-bearing mice is significantly affected by differences in the native composition of the gut microbiome or treatment with antibiotics, or by heterologous fecal transfer. Depletion of bacteria with vancomycin decreased the rate of tumor growth in mice from The Jackson Laboratory receiving ACT, whereas treatment with neomycin and metronidazole had no effect, indicating the role of specific bacteria in host response. Vancomycin treatment induced an increase in systemic CD8α+ DCs, which sustained systemic adoptively transferred antitumor T cells in an IL-12-dependent manner. In subjects undergoing allogeneic hematopoietic cell transplantation, we found that oral vancomycin also increased IL-12 levels. Collectively, our findings demonstrate an important role played by the gut microbiota in the antitumor effectiveness of ACT and suggest potentially new avenues to improve response to ACT by altering the gut microbiota.


Assuntos
Células Dendríticas/imunologia , Microbioma Gastrointestinal/imunologia , Transplante de Células-Tronco Hematopoéticas , Interações entre Hospedeiro e Microrganismos/imunologia , Imunoterapia Adotiva/métodos , Interleucina-12/imunologia , Neoplasias/terapia , Adulto , Idoso , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/imunologia , Bactérias/isolamento & purificação , Antígenos CD8/imunologia , Antígenos CD8/metabolismo , Linhagem Celular Tumoral/transplante , Estudos de Coortes , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Transplante de Microbiota Fecal , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Humanos , Interleucina-12/antagonistas & inibidores , Interleucina-12/genética , Interleucina-12/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Neomicina/administração & dosagem , Neoplasias/imunologia , Neoplasias/microbiologia , Linfócitos T/imunologia , Linfócitos T/transplante , Resultado do Tratamento , Vancomicina/administração & dosagem
16.
JAMA Surg ; 153(2): 114-121, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29049477

RESUMO

IMPORTANCE: Surgical site infections (SSIs) after colorectal surgery remain a significant complication, particularly for patients with cancer, because they can delay the administration of adjuvant therapy. A combination of oral antibiotics and mechanical bowel preparation (MBP) is a potential, yet controversial, SSI prevention strategy. OBJECTIVE: To determine the association of the addition of oral antibiotics to MBP with preventing SSIs in left colon and rectal cancer resections and its association with the timely administration of adjuvant therapy. DESIGN, SETTING, AND PARTICIPANTS: A retrospective review was performed of 89 patients undergoing left colon and rectal cancer resections from October 1, 2013, to December 31, 2016, at a single institution. A bowel regimen of oral antibiotics and MBP (neomycin sulfate, metronidazole hydrochloride, and magnesium citrate) was implemented August 1, 2015. Patients receiving MBP and oral antibiotics and those undergoing MBP without oral antibiotics were compared using univariate analysis. Multivariable logistic regression controlling for factors that may affect SSIs was used to evaluate the association between use of oral antibiotics and MBP and the occurrence of SSIs. MAIN OUTCOMES AND MEASURES: Surgical site infections within 30 days of the index procedure and time to adjuvant therapy. RESULTS: Of the 89 patients (5 women and 84 men; mean [SD] age, 65.3 [9.2] years) in the study, 49 underwent surgery with MBP but without oral antibiotics and 40 underwent surgery with MBP and oral antibiotics. The patients who received oral antibiotics and MBP were younger than those who received only MBP (mean [SD] age, 62.6 [9.1] vs 67.5 [8.8] years; P = .01), but these 2 cohorts of patients were otherwise similar in baseline demographic, clinical, and cancer characteristics. Surgical approach (minimally invasive vs open) and case type were similarly distributed; however, the median operative time of patients who received oral antibiotics and MBP was longer than that of patients who received MBP only (391 minutes [interquartile range, 302-550 minutes] vs 348 minutes [interquartile range, 248-425 minutes]; P = .03). The overall SSI rate was lower for patients who received oral antibiotics and MBP than for patients who received MBP only (3 [8%] vs 13 [27%]; P = .03), with no deep or organ space SSIs or anastomotic leaks in patients who received oral antibiotics and MBP compared with 9 organ space SSIs (18%; P = .004) and 5 anastomotic leaks (10%; P = .06) in patients who received MBP only. Despite this finding, there was no difference in median days to adjuvant therapy between the 2 cohorts (60 days [interquartile range, 46-73 days] for patients who received MBP only vs 72 days [interquartile range, 59-85 days] for patients who received oral antibiotics and MBP; P = .13). Oral antibiotics and MBP (odds ratio, 0.11; 95% CI, 0.02-0.86; P = .04) and minimally invasive surgery (odds ratio, 0.22; 95% CI, 0.05-0.89; P = .03) were independently associated with reduced odds of SSIs. CONCLUSIONS AND RELEVANCE: The combination of oral antibiotics and MBP is associated with a significant decrease in the rate of SSIs and should be considered for patients undergoing elective left colon and rectal cancer resections.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Neoplasias do Colo/cirurgia , Neoplasias Retais/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Administração Oral , Idoso , Fístula Anastomótica/etiologia , Catárticos/uso terapêutico , Ácido Cítrico/uso terapêutico , Colo Ascendente/cirurgia , Colo Sigmoide/cirurgia , Neoplasias do Colo/terapia , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Neomicina/uso terapêutico , Duração da Cirurgia , Compostos Organometálicos/uso terapêutico , Neoplasias Retais/terapia , Estudos Retrospectivos , Fatores de Tempo
17.
J Pediatr ; 186: 192-195.e1, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28438376

RESUMO

Superficial fungal infections are among the most commonly managed skin problems by general practitioners. Although evidence shows combination antifungal/corticosteroid topicals are more expensive and less effective than single-agent antifungals, practitioners continue to prescribe combination agents. We examined current prescription trends of 2 combination antifungal/corticosteroid medications, Lotrisone and Mycolog-II.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antifúngicos/uso terapêutico , Betametasona/uso terapêutico , Clotrimazol/uso terapêutico , Dermatomicoses/tratamento farmacológico , Glucocorticoides/uso terapêutico , Gramicidina/uso terapêutico , Neomicina/uso terapêutico , Nistatina/uso terapêutico , Triancinolona Acetonida/uso terapêutico , Adolescente , Criança , Pré-Escolar , Combinação de Medicamentos , Humanos , Lactente , Recém-Nascido , Padrões de Prática Médica
18.
Neural Plast ; 2017: 8283075, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28250994

RESUMO

The zebrafish has become an established model organism for the study of hearing and balance systems in the past two decades. The classical approach to examine hair cells is to use dye to conduct selective staining, which shows the number and morphology of hair cells but does not reveal their function. Startle response is a behavior closely related to the auditory function of hair cells; therefore it can be used to measure the function of hair cells. In this study, we developed a device to measure the startle response of zebrafish larvae. By applying various levels of stimulus, it showed that the system can discern a 10 dB difference. The hair cell in zebrafish can regenerate after damage due to noise exposure or drug treatment. With this device, we measured the startle response of zebrafish larvae during and after drug treatment. The results show a similar trend to the classical hair cell staining method. The startle response was reduced with drug treatment and recovered after removal of the drug. Together it demonstrated the capability of this behavioral assay in evaluating the hair cell functions of fish larvae and its potential as a high-throughput screening tool for auditory-related gene and drug discovery.


Assuntos
Comportamento Animal , Células Ciliadas Auditivas Internas/fisiologia , Reflexo de Sobressalto , Regeneração , Estimulação Acústica/métodos , Animais , Células Ciliadas Auditivas Internas/efeitos dos fármacos , Células Ciliadas Auditivas Internas/patologia , Larva , Neomicina/administração & dosagem , Reflexo de Sobressalto/efeitos dos fármacos , Peixe-Zebra
19.
J Neurosci Res ; 95(3): 869-875, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27400677

RESUMO

Today a cochlear implant (CI) may significantly restore auditory function, even for people with a profound hearing loss. Because the efficacy of a CI is believed to depend mainly on the remaining population of spiral ganglion neurons (SGNs), it is important to understand the timeline of the degenerative process of the auditory neurons following deafness. Guinea pigs were transtympanically deafened with neomycin, verified by recording auditory brainstem responses (ABRs), and then sacrificed at different time points. Loss of SGNs as well as changes in cell body and nuclear volume were estimated. To study the effect of delayed treatment, a group of animals that had been deaf for 12 weeks was implanted with a stimulus electrode mimicking a CI, after which they received a 4-week treatment with glial cell-derived neurotrophic factor (GDNF). The electrical responsiveness of the SGNs was measured by recording electrically evoked ABRs. There was a rapid degeneration during the first 7 weeks, shown as a significant reduction of the SGN population. The degenerative process then slowed, and there was no difference in the amount of remaining neurons between weeks 7 and 18. © 2016 The Authors Journal of Neuroscience Research Published by Wiley Periodicals, Inc.


Assuntos
Surdez/patologia , Orelha Interna/patologia , Estimulação Acústica , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Surdez/induzido quimicamente , Surdez/tratamento farmacológico , Surdez/fisiopatologia , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/uso terapêutico , Cobaias , Masculino , Neomicina/toxicidade , Inibidores da Síntese de Proteínas/toxicidade , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/patologia , Gânglio Espiral da Cóclea/efeitos dos fármacos , Gânglio Espiral da Cóclea/patologia , Fatores de Tempo
20.
Drug Chem Toxicol ; 40(4): 390-396, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27855522

RESUMO

CONTEXT: Ototoxicity due to medications, such as aminoglycosides, is irreversible, and free radicals in the inner ear are assumed to play a major role. Because melatonin has an antioxidant property, we hypothesize that it might mitigate hair cell injury by aminoglycosides. OBJECTIVE: The objective of this study was to evaluate whether melatonin has an alleviative effect on neomycin-induced hair cell injury in zebrafish (Danio rerio). METHODS: Various concentrations of melatonin were administered to 5-day post-fertilization zebrafish treated with 125 µM neomycin for 1 h. Surviving hair cells within four neuromasts were compared with that of a control group. Apoptosis was assessed via terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. The changes of ultrastructure were confirmed using a scanning electron microscope. RESULTS: Melatonin alleviated neomycin-induced hair cell injury in neuromasts (neomycin + melatonin 100 µM: 13.88 ± 0.91 cells, neomycin only: 7.85 ± 0.90 cells; n = 10, p < 0.05) and reduced neomycin-induced apoptosis in the TUNEL assay. In ultrastructural analysis, hair cells within the neuromasts in zebrafish were preserved exposed to 125 µM neomycin and 100 µM melatonin for 1 h in SEM findings. CONCLUSION: Melatonin is effective in alleviating aminoglycoside-induced hair cell injury in zebrafish. The results of this study demonstrated that melatonin has the potential to reduce apoptosis induced by aminoglycosides in zebrafish.


Assuntos
Antibacterianos/efeitos adversos , Sequestradores de Radicais Livres/metabolismo , Células Ciliadas Auditivas Internas/efeitos dos fármacos , Melatonina/metabolismo , Neomicina/efeitos adversos , Inibidores da Síntese de Proteínas/efeitos adversos , Animais , Animais Geneticamente Modificados , Antibacterianos/química , Apoptose/efeitos dos fármacos , Suplementos Nutricionais , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas Internas/ultraestrutura , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Neomicina/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Concentração Osmolar , Inibidores da Síntese de Proteínas/química , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
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