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1.
BMC Oral Health ; 23(1): 134, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894902

RESUMO

OBJECTIVES: Evaluate the role of platelet-rich fibrin (PRF) as a natural carrier for antibiotics delivery through the analysis of drug release and antimicrobial activity. MATERIALS AND METHODS: PRF was prepared according to the L-PRF (leukocyte- and platelet-rich fibrin) protocol. One tube was used as control (without drug), while an increasing amount of gentamicin (0.25 mg, G1; 0.5 mg, G2; 0.75 mg, G3; 1 mg, G4), linezolid (0.5 mg, L1; 1 mg, L2; 1.5 mg, L3; 2 mg, L4), vancomycin (1.25 mg, V1; 2.5 mg, V2; 3.75 mg, V3; 5 mg, V4) was added to the other tubes. At different times the supernatant was collected and analyzed. Strains of E. coli, P. aeruginosa, S. mitis, H. influenzae, S. pneumoniae, S. aureus were used to assess the antimicrobial effect of PRF membranes prepared with the same antibiotics and compared to control PRF. RESULTS: Vancomycin interfered with PRF formation. Gentamicin and linezolid did not change the physical properties of PRF and were released from membranes in the time intervals examined. The inhibition area analysis showed that control PRF had slight antibacterial activity against all tested microorganisms. Gentamicin-PRF had a massive antibacterial activity against all tested microorganisms. Results were similar for linezolid-PRF, except for its antibacterial activity against E. coli and P. aeruginosa that was comparable to control PRF. CONCLUSIONS: PRF loaded with antibiotics allowed the release of antimicrobial drugs in an effective concentration. Using PRF loaded with antibiotics after oral surgery may reduce the risk of post-operative infection, replace or enhance systemic antibiotic therapy while preserving the healing properties of PRF. Further studies are needed to prove that PRF loaded with antibiotics represents a topical antibiotic delivery tool for oral surgical procedures.


Assuntos
Anti-Infecciosos , Procedimentos Cirúrgicos Bucais , Fibrina Rica em Plaquetas , Humanos , Antibacterianos , Vancomicina/farmacologia , Staphylococcus aureus , Linezolida/farmacologia , Linezolida/uso terapêutico , Escherichia coli , Leucócitos , Gentamicinas/farmacologia
2.
J Antimicrob Chemother ; 76(7): 1786-1792, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33734351

RESUMO

BACKGROUND: In TB, therapeutic drug monitoring (TDM) is recommended for linezolid; however, implementation is challenging in endemic settings. Non-invasive saliva sampling using a mobile assay would increase the feasibility of TDM. OBJECTIVES: To validate a linezolid saliva assay using a mobile UV spectrophotometer. METHODS: The saliva assay was developed using NanoPhotometer NP80® and linezolid concentrations were quantified using second-order derivative spectroscopy. Sample preparation involved liquid-liquid extraction of saliva, using saturated sodium chloride and ethyl acetate at 1:1:3 (v/v/v). The assay was validated for accuracy, precision, selectivity, specificity, carry-over, matrix effect, stability and filters. Acceptance criteria were bias and coefficient of variation (CV) <15% for quality control (QC) samples and <20% for the lower limit of quantification (LLOQ). RESULTS: Linezolid concentrations correlated with the amplitude between 250 and 270 nm on the second-order derivative spectra. The linezolid calibration curve was linear over the range of 3.0 to 25 mg/L (R2 = 0.99) and the LLOQ was 3.0 mg/L. Accuracy and precision were demonstrated with bias of -7.5% to 2.7% and CV ≤5.6%. The assay met the criteria for selectivity, matrix effect, carry-over, stability (tested up to 3 days) and use of filters (0.22 µM Millex®-GV and Millex®-GP). Specificity was tested with potential co-medications. Interferences from pyrazinamide, levofloxacin, moxifloxacin, rifampicin, abacavir, acetaminophen and trimethoprim were noted; however, with minimal clinical implications on linezolid dosing. CONCLUSIONS: We validated a UV spectrophotometric assay using non-invasive saliva sampling for linezolid. The next step is to demonstrate clinical feasibility and value to facilitate programmatic implementation of TDM.


Assuntos
Monitoramento de Medicamentos , Saliva , Cromatografia Líquida de Alta Pressão , Linezolida , Moxifloxacina
3.
J Infect Chemother ; 26(10): 1062-1065, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32563555

RESUMO

Linezolid is an oxazolidinone antimicrobial agent often used to treat multidrug-resistant Gram-positive bacterial infections. The common adverse reactions of linezolid are diarrhea, nausea, headache and bone marrow suppression, and so on. Here, we report the first case of teeth discoloration induced by linezolid linked with extrinsic discoloration in China Mainland. This case report highlights a rare adverse reactions of a commonly used antibiotic.


Assuntos
Infecções por Bactérias Gram-Positivas , Oxazolidinonas , Acetamidas , Antibacterianos/efeitos adversos , Criança , China , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Linezolida/efeitos adversos , Oxazolidinonas/efeitos adversos
4.
Blood Purif ; 49(3): 295-301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31995801

RESUMO

INTRODUCTION: Renal replacement therapy (RRT) is widely used in the treatment of septic acute kidney injury. However, little is known about how the adsorption properties of hemofilters used in RRT affect antibiotic concentration. Because a cytokine-adsorption membrane is frequently used in RRT, it is important to determine the antibiotic adsorption capacity of this membrane. OBJECTIVE: The present study aimed to investigate the antibiotic adsorption capacity of different hemofilter membranes by in vitro experiments using 2 antibacterial agents (linezolid and doripenem). METHODS: We performed experimental hemofiltration in vitro using polyacrylonitrile (AN69ST), polymethylmethacrylate (PMMA), and polysulfone (PS) hemofilters for 1,440 min. The test solution was a 1,000-mL substitution fluid containing 30 µg/mL linezolid and 120 µg/mL doripenem. We measured drug concentrations at the inlet, outlet, and filtrate ports of the hemofilters for 1,440 min and calculated the sieving coefficient (SC) and adsorption rate (Ra) of the drugs onto the hemofilters. RESULTS: The amount of linezolid adsorbed onto AN69ST, PMMA, and PS membranes was decreased relative to that in the control group at 15 min (p < 0.05). However, no SC for linezolid was obtained thereafter. The Ra of linezolid onto AN69ST, PMMA, and PS membranes was higher than that in the control group (p < 0.05). In contrast, no significant differences were observed in the concentrations and Ra values of doripenem adsorbed onto AN69ST, PMMA, and PS membranes compared with those in the control group. CONCLUSIONS: Doripenem was not adsorbed onto PMMA, PS, and AN69ST membranes. Linezolid was adsorbed onto PMMA, PS, and AN69ST membranes, but only temporarily, and this did not affect drug bioavailability.


Assuntos
Antibacterianos/isolamento & purificação , Doripenem/isolamento & purificação , Hemofiltração/instrumentação , Linezolida/isolamento & purificação , Membranas Artificiais , Resinas Acrílicas/química , Adsorção , Antibacterianos/análise , Doripenem/análise , Humanos , Linezolida/análise , Polímeros/química , Polimetil Metacrilato/química , Sulfonas/química
5.
Drug Dev Ind Pharm ; 46(1): 109-121, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31905297

RESUMO

Objective: The choice of a desirable solvent/solvent system is fundamental for optimization of electrospinning by altering the rheological and electrostatic properties of the polymer solutions.Methods: The effects of the solvents and their properties on the viscosity and spinnability of the polymer solutions and the diameter, morphology, in vitro drug release, drug release mechanisms, antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and mechanical properties of electrospun poly-(d,l-lactide-co-glycolide) (PLGA) nanofibers were investigated. Dichloromethane (DCM), dimethylformamide (DMF), various ratios of DCM:DMF, and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) were used as solvents.Results: Although solutions containing DCM/DMF alone were not spinnable, different ratios of DCM:DMF and HFIP were determined as suitable solvents to produce nanofibers because of high enough conductivity, viscosity, and low enough surface tension of the solutions. The DCM:DMF ratio was highly effective on viscosity, nanofiber diameter, morphology, and linezolid release rate. The viscosity of HFIP containing solution was higher and the obtained nanofibers were thicker and smoother with better mechanical properties. The release of nanofibers containing HFIP at a concentration of 10% w/v PLGA was more prolonged than nanofibers containing DCM:DMF mixture. The effect of linezolid content on nanofibers was also investigated. As the amount of linezolid increased, nanofiber diameter and drug release increased and bead formation was observed. While antibacterial activity with nanofibers for which DCM:DMF was used, lasted for 13 days, it was extended to 16 days in nanofibers for which HFIP was used.Conclusions: Type and ratio of the solvent system affected viscosity and spinnability of the solutions, the average nanofiber diameter, morphology, in vitro activity and mechanical properties of the obtained electrospun nanofibers.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos , Linezolida/administração & dosagem , Nanofibras , Antibacterianos/química , Antibacterianos/farmacologia , Química Farmacêutica , Preparações de Ação Retardada , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Linezolida/química , Linezolida/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Solventes/química , Eletricidade Estática , Fatores de Tempo , Viscosidade
6.
Dermatol Online J ; 26(9)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33054940

RESUMO

Cutaneous non-tuberculous mycobacterial (NTM) infections have rapidly increased in incidence in recent years. Currently there is no standard treatment and the variable and nonspecific ways in which cutaneous NTM infection presents makes it a therapeutic and diagnostic challenge. We describe a 67-year-old immunocompetent woman with cutaneous NTM infection after she recently underwent a root canal procedure. Although the species was not identified and she was unable to tolerate multiple antibiotics, she ultimately responded well to three months of treatment with linezolid. Given that cutaneous NTM infection can present in immunocompetent patients and that the incidence is rising, it is important for clinicians to maintain a high index of clinical suspicion, especially in patients with a recent history of surgery, trauma, or cosmetic procedures. Linezolid has coverage against non-tuberculous mycobacteria and is an effective therapeutic option for cutaneous NTM cases in which identification to the species level is not possible or when adverse effects limit therapeutic options.


Assuntos
Antibacterianos/uso terapêutico , Linezolida/uso terapêutico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Dermatopatias Bacterianas/tratamento farmacológico , Idoso , Biópsia , Feminino , Humanos , Infecções por Mycobacterium não Tuberculosas/patologia , Tratamento do Canal Radicular/efeitos adversos , Dermatopatias Bacterianas/patologia
7.
Curr Opin Pulm Med ; 25(3): 271-280, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30865034

RESUMO

PURPOSE OF REVIEW: Treatment of drug-sensitive tuberculosis (TB) is effective, whereas that of multidrug-resistant and extensively drug-resistant TB as well as nontuberculous mycobacterial (NTM) disease are less so. Therapy in general requires good adherence to potentially toxic drug regimens over prolonged periods. Poor adherence is associated with resistance development and poor outcome. This review will present promising new treatments, both new drugs and regimens, for difficult mycobacterial pulmonary infections. RECENT FINDINGS: A number of new and repurposed drugs including bedaquiline, delamanid, pretomanid, linezolid and clofazimine, and drug regimens, such as the The Evaluation of a Standard Treatment Regimen of Anti-tuberculosis Drugs for Patients With MDR-TB (STREAM) trial regimens, are currently progressing from basic research through clinical trials.


Assuntos
Antibacterianos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Pneumopatias/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Amicacina/administração & dosagem , Antibacterianos/administração & dosagem , Clofazimina/uso terapêutico , Diarilquinolinas/uso terapêutico , Humanos , Linezolida/uso terapêutico , Lipossomos , Pneumopatias/microbiologia , Testes de Sensibilidade Microbiana , Nitroimidazóis/uso terapêutico , Oxazóis/uso terapêutico
9.
Med Sci Monit ; 21: 909-14, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25819685

RESUMO

BACKGROUND: The aim of this study was to evaluate the effectiveness of linezolid, teicoplanin, and vancomycin in prevention of prosthetic vascular graft infections in a vascular graft infection model. MATERIAL AND METHODS: Fifty rats were divided into 5 groups. A polytetrafluoroethylene graft was implanted on the back of each rat. Methicillin-resistant Staphylococcus aureus (MRSA) strain was inoculated into all rats except Group 1. Group 2 was not given any treatment, Group 3 received linezolid, Group 4 received vancomycin, and Group 5 received teicoplanin. The grafts were removed for microbiological and histological examinations on the 7th day. In addition, C-reactive protein and prealbumin levels and leukocyte counts in obtained blood specimens were determined. RESULTS: Group 1 did not have infection. Group 2 had bacteria 5.7 × 10(4) CFU/cm(2). Group 3 and Group 4 had less bacterial growth. Group 5 had no bacterial growth. The number of bacteria was significantly higher in Group 2 than in the other experimental groups and the control group (p<0.001). Although there was no bacterial growth in Group 5, it did not significantly differ from Group 3 and Group 4. Group 2 had a significantly higher CRP level and leukocyte count and a significantly lower prealbumin level than the other groups. CONCLUSIONS: Linezolid, teicoplanin, and vancomycin are effective in prevention of prosthetic vascular graft infections.


Assuntos
Linezolida/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/fisiologia , Politetrafluoretileno/efeitos adversos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/prevenção & controle , Teicoplanina/uso terapêutico , Vancomicina/uso terapêutico , Animais , Proteína C-Reativa/metabolismo , Modelos Animais de Doenças , Leucócitos/patologia , Linezolida/farmacologia , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pré-Albumina/metabolismo , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/patologia , Ratos Wistar , Teicoplanina/farmacologia , Resultado do Tratamento , Vancomicina/farmacologia
10.
J Oral Maxillofac Surg ; 73(4): 666-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25544295

RESUMO

Panton-valentine leukocidin (PVL) is a pore-forming cytotoxin produced by some clones of Staphylococcus aureus that is associated with infections ranging from uncomplicated skin and soft tissue infections to life-threatening necrotizing pneumonia. PVL S aureus-associated maxillofacial infections are rarely reported; therefore, a high degree of clinical suspicion is warranted and close liaison with microbiologists and appropriate samples are required for optimal management. This report discusses the management and learning points from 3 such cases managed by the Greater Glasgow and Clyde National Health Service maxillofacial surgical teams.


Assuntos
Toxinas Bacterianas/análise , Celulite (Flegmão)/microbiologia , Exotoxinas/análise , Face/microbiologia , Leucocidinas/análise , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/patogenicidade , Abscesso/microbiologia , Acetamidas/uso terapêutico , Adolescente , Adulto , Antibacterianos/uso terapêutico , Cárie Dentária/microbiologia , Evolução Fatal , Feminino , Humanos , Linezolida , Doenças Labiais/microbiologia , Abscesso Pulmonar/microbiologia , Masculino , Pescoço/microbiologia , Oxazolidinonas/uso terapêutico
11.
Biomed Chromatogr ; 29(9): 1428-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25678451

RESUMO

Linezolid is an antimicrobial agent for the treatment of multiresistant Gram-positive infections. A practical high-performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o-ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5-50 µg/mL using a 200 µL sample volume. The intra- and interday precisions were all <6.44% for plasma and 5.60% for saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid-liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 µL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Linezolida/análise , Saliva/química , Adulto , Antibacterianos/sangue , Humanos , Linezolida/sangue , Masculino , Pessoa de Meia-Idade
12.
Zhonghua Yi Xue Za Zhi ; 94(25): 1976-8, 2014 Jul 01.
Artigo em Zh | MEDLINE | ID: mdl-25253015

RESUMO

OBJECTIVE: To explore the elution properties of linezolid bone cement so as to guide the clinical application of linezolid bone cement in the treatment of infection after total joint arthroplasty. METHODS: The specimens of bone cement (40 g each) were divided into 6 groups depending on mixed different contents with linezolid (5 specimens in each group), group I (1.2 g), group II (2.4 g), group III (3.6 g), group IV (4.8 g), group V (6.0 g) and group VI (7.2 g). The time-dependent elution of linezolid from bone cement was measured by high performance liquid chromatography (HPLC). RESULTS: The release rate of linezolid bone cement samples was positively correlated with the concentration of antibiotics. And he release rate increased with the rising concentrations. The release of all groups dropped dramatically at Day 1. And as of Day 2 there was a slow release at a very low level. The elution of all groups persisted through 7 weeks. The analysis of variance between groups showed significant differences in release rates. And further examination by q test revealed that the release of group of 3.6-7.2 g was significantly higher than other groups. CONCLUSION: The drainage tube should be clamped at Day 1 post-operation so that there is a full release of high concentration of linezolid. Adding 3.6 g linezolid to 40 g cement may provide better cost-effective outcomes.


Assuntos
Acetamidas , Cimentos Ósseos , Oxazolidinonas , Antibacterianos , Humanos , Linezolida , Masculino
13.
J Ayub Med Coll Abbottabad ; 26(3): 401-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25671958

RESUMO

Linezolid induced black hairy tongue is a rare benign reversible side effect of linezolid therapy. We report a case of a 61 year old diabetic lady who developed thrombocytopenia and black hairy discoloration of the tongue after being prescribed linezolid for foot osteomyelitis by the orthopaedic surgeon. Patient was encouraged to practice good oral dental hygiene, advised to use a soft tooth brush, regular mouth wash and baking soda containing tooth paste. The condition resolved four weeks after cessation of the antibiotic therapy.


Assuntos
Acetamidas/efeitos adversos , Anti-Infecciosos/efeitos adversos , Oxazolidinonas/efeitos adversos , Doenças Raras/induzido quimicamente , Língua Pilosa/induzido quimicamente , Feminino , , Humanos , Linezolida , Pessoa de Meia-Idade , Osteomielite/tratamento farmacológico
14.
Drug Deliv Transl Res ; 14(1): 80-102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37542190

RESUMO

The objective of the current study was to create an efficient, minimally invasive combined system comprising in situ forming hydrogel loaded with both spray-dried polymeric nanoparticles encapsulating linezolid and nanohydroxyapatite for local injection to bones or their close vicinity. The developed system was designed for a dual function namely releasing the drug in a sustained manner for long-term treatment of bone infections and supporting bone proliferation and new tissues generation. To achieve these objectives, two release sustainment systems for linezolid were optimized namely a composite in situ forming chitosan hydrogel and spray-dried PLGA/PLA solid nanoparticles. The composite, in situ forming hydrogel of chitosan was prepared using two different gelling agents namely glycerophosphate (GP) and sodium bicarbonate (NaHCO3) at 3 different concentrations each. The spray-dried linezolid-loaded PLGA/PLA nanoparticles were developed using a water-soluble carrier (PVP K30) and a lipid soluble one (cetyl alcohol) along with 3 types of DL-lactide and/or DL-lactide-co-glycolide copolymer using nano-spray-drying technique. Finally, the optimized spray-dried linezolid nanoparticles were incorporated into the optimized composite hydrogel containing nanohydroxy apatite (nHA). The combined hydrogel/nanoparticle systems displayed reasonable injectability with excellent gelation time at 37 °C. The optimum formulae sustained the release of linezolid for 7-10 days, which reveals its ability to reduce the frequency of injection during the course of treatment of bones infections and increase the patients' compliance. They succeeded to alleviate the bone infections and the associated clinical, biochemical, radiological, and histopathological changes within 2-4 weeks of injection. As to the state of art in this study and to the best of our knowledge, no such complete and systematic study on this type of combined in situ forming hydrogel loaded with spray-dried nanoparticles of linezolid is available yet in literatures.


Assuntos
Quitosana , Nanopartículas , Humanos , Linezolida , Hidrogéis , Poliésteres
15.
Recent Adv Antiinfect Drug Discov ; 19(4): 322-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38243985

RESUMO

BACKGROUND: Linezolid (LNZ) is a synthetic oxazolidinone antibiotic approved for the treatment of uncomplicated and complicated skin and soft tissue infections caused by gram-positive bacteria. Typically, LNZ is administered orally or intravenously in most cases. However, prolonged therapy is associated with various side effects and lifethreatening complications. Cutaneous application of LNZ will assist in reducing the dose, hence minimizing the unwanted side/adverse effects associated with oral administration. Dermal delivery provides an alternative route of administration, facilitating a local and sustained concentration of the antimicrobial at the site of infection. OBJECTIVE: The current research work aimed to formulate solid lipid nanoparticles (SLNs) based gel for dermal delivery of LNZ in the management of uncomplicated skin and soft tissue infections to maximise its benefits and minimise the side effects. METHODS: SLNs were prepared by high-shear homogenisation and ultrasound method using Dynasan 114 as solid lipid and Pluronic F-68 as surfactant. The effect of surfactant concentration, drug-to-lipid ratio, and sonication time was investigated on particle size, zeta potential, and entrapment efficiency using the Taguchi design. The main effect plot of means and signal-to-noise ratio were generated to determine the optimized formulation. The optimized batch was formulated into a gel, and ex vivo permeation study, in vitro and in vivo antibacterial activity were conducted. RESULTS: The optimised process parameters to achieve results were 2% surfactant concentration, a drug-to-lipid ratio of 1:2, and 360 s of sonication time. The optimized batch was 206.3± 0.17nm in size with a surface charge of -24.4± 4.67mV and entrapment efficiency of 80.90 ± 0.45%. SLN-based gel demonstrated anomalous transport with an 85.43% in vitro drug release. The gel showed a 5.03 ± 0.15 cm zone of inhibition while evaluated for in vitro antibacterial activity against Staphylococcus aureus. Ex vivo skin permeation studies demonstrated 20.308% drug permeation and 54.96% cutaneous deposition. In-vivo results showed a significant reduction in colony-forming units in the group treated with LNZ SLN-based gel. CONCLUSION: Ex vivo studies ascertain the presence of the drug at the desired site and improve therapy. In vivo results demonstrated the ability of SLN-based gel to significantly reduce the number of bacteria in the stripped infection model. The utilization of SLN as an LNZ carrier holds significant promise in dermal delivery.


Assuntos
Administração Cutânea , Antibacterianos , Géis , Linezolida , Lipídeos , Nanopartículas , Linezolida/administração & dosagem , Linezolida/farmacocinética , Linezolida/farmacologia , Linezolida/química , Nanopartículas/química , Animais , Géis/química , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/farmacocinética , Antibacterianos/química , Lipídeos/química , Lipídeos/administração & dosagem , Absorção Cutânea/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Tamanho da Partícula , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/microbiologia , Composição de Medicamentos , Lipossomos
16.
Biomed Pharmacother ; 172: 116228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320333

RESUMO

BACKGROUND: Linezolid has been reported to protect against chronic bone and joint infection. In this study, linezolid was loaded into the 3D printed poly (lactic-co-glycolic acid) (PLGA) scaffold with nano-hydroxyapatite (HA) to explore the effect of this composite scaffold on infected bone defect (IBD). METHODS: PLGA scaffolds were produced using the 3D printing method. Drug release of linezolid was analyzed by elution and high-performance liquid chromatography assay. PLGA, PLGA-HA, and linezolid-loaded PLGA-HA scaffolds, were implanted into the defect site of a rabbit radius defect model. Micro-CT, H&E, and Masson staining, and immunohistochemistry were performed to analyze bone infection and bone healing. Evaluation of viable bacteria was performed. The cytocompatibility of 3D-printed composite scaffolds in vitro was detected using human bone marrow mesenchymal stem cells (BMSCs). Long-term safety of the scaffolds in rabbits was evaluated. RESULTS: The linezolid-loaded PLGA-HA scaffolds exhibited a sustained release of linezolid and showed significant antibacterial effects. In the IBD rabbit models implanted with the scaffolds, the linezolid-loaded PLGA-HA scaffolds promoted bone healing and attenuated bone infection. The PLGA-HA scaffolds carrying linezolid upregulated the expression of osteogenic genes including collagen I, runt-related transcription factor 2, and osteocalcin. The linezolid-loaded PLGA-HA scaffolds promoted the proliferation and osteogenesis of BMSCs in vitro via the PI3K/AKT pathway. Moreover, the rabbits implanted with the linezolid-loaded scaffolds showed normal biochemical profiles and normal histology, which suggested the safety of the linezolid-loaded scaffolds. CONCLUSION: Overall, the linezolid-loaded PLGA-HA scaffolds fabricated by 3D printing exerts significant bone repair and anti-infection effects.


Assuntos
Durapatita , Alicerces Teciduais , Animais , Coelhos , Humanos , Durapatita/química , Alicerces Teciduais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Linezolida/farmacologia , Fosfatidilinositol 3-Quinases , Impressão Tridimensional
17.
Antimicrob Agents Chemother ; 57(8): 3676-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23689722

RESUMO

Linezolid plays an increasingly important role in the treatment of multidrug-resistant tuberculosis (MDR-TB). However, patients should be carefully monitored due to time- and dose-dependent toxicity. Clarithromycin plays a more modest role. Therapeutic drug monitoring may contribute to assessment of treatment regimens, helping to reduce toxicity while maintaining adequate drug exposure. Oral fluid sampling could provide a welcome alternative in cases where conventional plasma sampling is not possible or desirable. The aim of this study was to clinically validate the analysis of linezolid and clarithromycin and its metabolite hydroxyclarithromycin in oral fluid of patients with multidrug-resistant tuberculosis. Serum and oral fluid samples were simultaneously obtained and analyzed by using validated methods, after extensive cross-validation between the two matrices. Passing-Bablok regressions and Bland-Altman analysis showed that oral fluid analysis of linezolid and clarithromycin appeared to be suitable for therapeutic drug monitoring in MDR-TB patients. No correction factor is needed for the interpretation of linezolid oral fluid concentrations with a ratio of the linezolid concentration in serum to that in oral fluid of 0.97 (95% confidence interval [CI], 0.92 to 1.02). However, the clarithromycin concentration serum/clarithromycin concentration in oral fluid ratio is 3.07 (95% CI, 2.45 to 3.69). Analysis of hydroxyclarithromycin in oral fluid was not possible in this study due to a nonlinear relationship between the concentration in serum and that in oral fluid. In conclusion, the analysis of linezolid (no correction factor) and clarithromycin (correction factor of 3) in oral fluid is applicable for therapeutic drug monitoring in cases of multidrug-resistant tuberculosis as an alternative to conventional serum sampling. Easy sampling using a noninvasive technique may facilitate therapeutic drug monitoring for specific patient categories.


Assuntos
Acetamidas/farmacocinética , Antituberculosos/farmacocinética , Claritromicina/farmacocinética , Monitoramento de Medicamentos/métodos , Oxazolidinonas/farmacocinética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Acetamidas/sangue , Adulto , Área Sob a Curva , Claritromicina/análogos & derivados , Claritromicina/sangue , Intervalos de Confiança , Feminino , Humanos , Linezolida , Masculino , Taxa de Depuração Metabólica , Oxazolidinonas/sangue , Estudos Prospectivos , Saliva/química , Adulto Jovem
18.
Appl Microbiol Biotechnol ; 97(6): 2609-16, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22965190

RESUMO

A newly isolated Aspergillus niger strain containing epoxide hydrolase was used to resolve racemic glycidyl azide and four derivatives to the (R)-enantiomers. After optimization of the biotransformation conditions, (R)-glycidyl azide was produced with good enantioselectivity (e.e.s > 95 %, E > 20). The substrate structure, pH, and reaction time were found to have profound influences on the catalytic property of A. niger ZJUTZQ208. Enantiopure glycidyl azide was further utilized to synthesize linezolid in good yield, indicating it is a new and concise synthon for chiral vicinal amino alcohols. Enzyme-substrate docking studies were carried out with glycidyl azide to study the selectivity of this strain.


Assuntos
Amino Álcoois/metabolismo , Aspergillus niger/metabolismo , Polímeros/metabolismo , Acetamidas/metabolismo , Antibacterianos/metabolismo , Aspergillus niger/classificação , Aspergillus niger/enzimologia , Aspergillus niger/isolamento & purificação , Biotransformação , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Epóxido Hidrolases/química , Epóxido Hidrolases/metabolismo , Genes de RNAr , Concentração de Íons de Hidrogênio , Linezolida , Modelos Moleculares , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Oxazolidinonas/metabolismo , Filogenia , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Fatores de Tempo
19.
Int J Pharm ; 642: 123067, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37257794

RESUMO

This study deals with the development of novel poly(lactic acid)-poly(ethylene glycol) nanoparticles (PLA-PEG NPs) for the efficient and prolonged delivery of Linezolid (LNZ), a synthetic antibacterial agent used against methicillin-resistant Staphylococcus aureus (MRSA). A two-step synthetic strategy based on carbodiimide coupling and copper-catalyzed azide-alkyne cycloaddition was first exploited for the conjugation of PLA with PEG. The encapsulation of LNZ into medium-molecular-weight PLA-PEG NPs was carried out by different methods including nanoprecipitation and dialysis. The optimal PLA-PEG@LNZ nanoformulation resulted in 3.5% LNZ payload (15% encapsulation efficiency, with a 10:3 polymer to drug mass ratio) and sustained release kinetics with 65% of entrapped antibiotic released within 80 h. Moreover, the zeta potential values (from -31 to -39 mV) indicated a good stability without agglomeration even after freeze-drying and lyophilization. The PLA-PEG@LNZ NPs exerted antimicrobial activity against a panel of Gram-positive bacteria responsible for human infections, such as Staphylococcus aureus including MRSA, Staphylococcus epidermidis, Staphylococcus lugdunensis and vancomycin-resistant Enterococcus faecium (VREfm). Moreover, PLA-PEG@LNZ NPs showed inhibitory activity on both planktonic growth and preformed biofilm of MRSA. The antibacterial activity of LNZ incorporated in polymeric NPs was well preserved and the nanosystem served as an antibiotic enhancer with a potential role in MRSA-associated infections management.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Humanos , Linezolida/farmacologia , Polímeros , Antibacterianos/farmacologia , Polietilenoglicóis , Poliésteres , Testes de Sensibilidade Microbiana
20.
Front Cell Infect Microbiol ; 13: 1258561, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908760

RESUMO

Background: Tuberculosis (TB) is a rare but potentially devastating complication in hematopoietic stem cell transplantation (HSCT) recipients. Myelosuppression-related antibiotics should be used cautiously in patients with hematological malignancies, especially those undergoing bone marrow transplantation and receiving bone marrow suppression therapy. Although linezolid has become the recommended drug for severe TB, its hematological toxicity is still an obstacle to its clinical application. Contezolid is a new representative of oxazolidinones in clinical development, showing superior anti-infection efficacy, but there have been no reports on the treatment of post-HSCT TB. Case presentation: We reported a patient with acute lymphoblastic leukemia suffered from pulmonary TB infection after HSCT. During anti-TB treatment, the patient had a poor response to linezolid-containing regimen, and developed side effects such as gingival bleeding and thrombocytopenia, so the administration was switched to contezolid. After 15 days of continuous treatment, the patient's platelet increased to 58×109/L, and he was discharged in stable condition. During subsequent anti-TB treatment with contezolid for more than 7 months, the platelets remained stable, and no hematological adverse reactions and no symptoms of peripheral neuropathy were observed. Moreover, repeat imaging showed that the bilateral lung lesions were significantly reduced, indicating a good outcome for the patient. Conclusion: This was the first successful case of post-HSCT TB patients treated with contezolid-containing antibiotic management strategies, which exhibited remarkable efficacy and good safety in this deadly disease.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Tuberculose Pulmonar , Tuberculose , Masculino , Humanos , Linezolida/uso terapêutico , Tuberculose/diagnóstico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Tuberculose Pulmonar/diagnóstico , Antibacterianos/uso terapêutico
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