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1.
Antimicrob Agents Chemother ; 66(12): e0092122, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36448795

RESUMO

CUO246, a novel DNA gyrase/topoisomerase IV inhibitor, is active in vitro against a broad range of Gram-positive, fastidious Gram-negative, and atypical bacterial pathogens and retains activity against quinolone-resistant strains in circulation. The frequency of selection for single step mutants of wild-type S. aureus with reduced susceptibility to CUO246 was <4.64 × 10-9 at 4× and 8× MIC and remained low when using an isogenic QRDR mutant (<5.24 × 10-9 at 4× and 8× MIC). Biochemical assays indicated that CUO246 had potent inhibitory activity against both DNA gyrase (GyrAB) and topoisomerase IV (ParCE). Furthermore, CUO246 showed rapid bactericidal activity in time-kill assays and potent in vivo efficacy against S. aureus in a neutropenic murine thigh infection model. These results suggest that CUO246 may be useful in treating infections by various causative agents of acute skin and skin structure infections, respiratory tract infections, and sexually transmitted infections.


Assuntos
DNA Girase , DNA Topoisomerase IV , Animais , Camundongos , DNA Girase/genética , DNA Topoisomerase IV/genética , Inibidores da Topoisomerase II/farmacologia , DNA Bacteriano , Staphylococcus aureus , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
2.
BMC Geriatr ; 22(1): 99, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35120457

RESUMO

BACKGROUND: Older adults (≥65 years) with diabetes and multiple chronic conditions (MCC) (> 2 chronic conditions) experience reduced function and quality of life, increased health service use, and high mortality. Many community-based self-management interventions have been developed for this group, however the evidence for their effectiveness is limited. This paper presents the protocol for a randomized controlled trial (RCT) comparing the effectiveness and implementation of the Aging, Community and Health Research Unit-Community Partnership Program (ACHRU-CPP) to usual care in older adults with diabetes and MCC and their caregivers. METHODS: We will conduct a cross-jurisdictional, multi-site implementation-effectiveness type II hybrid RCT. Eligibility criteria are: ≥65 years, diabetes diagnosis (Type 1 or 2) and at least one other chronic condition, and enrolled in a primary care or diabetes education program. Participants will be randomly assigned to the intervention (ACHRU-CPP) or control arm (1:1 ratio). The intervention arm consists of home/telephone visits, monthly group wellness sessions, multidisciplinary case conferences, and system navigation support. It will be delivered by registered nurses and registered dietitians/nutritionists from participating primary care or diabetes education programs and program coordinators from community-based organizations. The control arm consists of usual care provided by the primary care setting or diabetes education program. The primary outcome is the change from baseline to 6 months in mental functioning. Secondary outcomes will include, for example, the change from baseline to 6 months in physical functioning, diabetes self-management, depressive symptoms, and cost of use of healthcare services. Analysis of covariance (ANCOVA) models will be used to analyze all outcomes, with intention-to-treat analysis using multiple imputation to address missing data. Descriptive and qualitative data from older adults, caregivers and intervention teams will be used to examine intervention implementation, site-specific adaptations, and scalability potential. DISCUSSION: An interprofessional intervention supporting self-management may be effective in improving health outcomes and client/caregiver experience and reducing service use and costs in this complex population. This pragmatic trial includes a scalability assessment which considers a range of effectiveness and implementation criteria to inform the future scale-up of the ACHRU-CPP. TRIAL REGISTRATION: Clinical Trials.gov Identifier NCT03664583 . Registration date: September 10, 2018.


Assuntos
Diabetes Mellitus , Múltiplas Afecções Crônicas , Idoso , Humanos , Envelhecimento , Análise Custo-Benefício , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/terapia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Artigo em Inglês | MEDLINE | ID: mdl-31061156

RESUMO

Infections caused by antibiotic-resistant Gram-negative bacteria expressing extended-spectrum ß-lactamases and carbapenemases are a growing global problem resulting in increased morbidity and mortality with limited treatment options. LYS228 is a novel intravenous monobactam antibiotic targeting penicillin binding protein 3 with potent activity against Enterobacteriaceae, including multidrug-resistant clinical isolates expressing serine and metallo-ß-lactamases. In this study, we evaluated the safety, tolerability, and pharmacokinetics of single and multiple intravenous doses of LYS228 in healthy volunteers. LYS228 was safe: no serious adverse events were reported. Adverse events, with the exception of catheter-related events, occurred sporadically, with similar incidences between LYS228 and placebo groups. No apparent adverse event-dose relationship was identified. LYS228 was not associated with any clinically significant dose-related hematologic, hepatic, or renal laboratory abnormalities. The most frequently observed adverse events were local injection site reactions, noted in 91.7% and 75.0% of subjects administered multiple doses of LYS228 and placebo, respectively. LYS228 demonstrated pharmacokinetic properties consistent with those of other ß-lactam antibiotics, with systemic exposures slightly greater than dose proportional, short terminal half-lives (between 1.0 and 1.6 h) with no significant accumulation, and rapid clearance predominantly through urinary excretion.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Monobactamas/efeitos adversos , Monobactamas/farmacocinética , Adulto , Antibacterianos/administração & dosagem , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Monobactamas/administração & dosagem , beta-Lactamases/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-30061296

RESUMO

Twenty-three Klebsiella pneumoniae (blaDHA-1) clinical isolates exhibited a range of susceptibilities to LYS228, with MICs of ≥8 µg/ml for 9 of these. Mutants with decreased susceptibility to LYS228 and upregulated expression of blaDHA-1 were selected from representative isolates. These had mutations in the chromosomal peptidoglycan recycling gene mpl or ampD Preexisting mpl mutations were also found in some of the clinical isolates examined, and these had strongly upregulated expression of blaDHA-1.


Assuntos
Antibacterianos/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Mutação/genética , Plasmídeos/genética , beta-Lactamases/genética , beta-Lactamases/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-30038040

RESUMO

LYS228 is a novel monobactam with potent activity against Enterobacteriaceae LYS228 is stable to metallo-ß-lactamases (MBLs) and serine carbapenemases, including Klebsiella pneumoniae carbapenemases (KPCs), resulting in potency against the majority of extended-spectrum ß-lactamase (ESBL)-producing and carbapenem-resistant Enterobacteriaceae strains tested. Overall, LYS228 demonstrated potent activity against 271 Enterobacteriaceae strains, including multidrug-resistant isolates. Based on MIC90 values, LYS228 (MIC90, 1 µg/ml) was ≥32-fold more active against those strains than were aztreonam, ceftazidime, ceftazidime-avibactam, cefepime, and meropenem. The tigecycline MIC90 was 4 µg/ml against the strains tested. Against Enterobacteriaceae isolates expressing ESBLs (n = 37) or displaying carbapenem resistance (n = 77), LYS228 had MIC90 values of 1 and 4 µg/ml, respectively. LYS228 exhibited potent bactericidal activity, as indicated by low minimal bactericidal concentration (MBC) to MIC ratios (MBC/MIC ratios of ≤4) against 97.4% of the Enterobacteriaceae strains tested (264/271 strains). In time-kill studies, LYS228 consistently achieved reductions in CFU per milliliter of 3 log10 units (≥99.9% killing) at concentrations ≥4× MIC for Escherichia coli and K. pneumoniae reference strains, as well as isolates encoding TEM-1, SHV-1, CTX-M-14, CTX-M-15, KPC-2, KPC-3, and NDM-1 ß-lactamases.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Monobactamas/farmacologia , Compostos Azabicíclicos/farmacologia , Aztreonam/farmacologia , Cefepima/farmacologia , Ceftazidima/farmacologia , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Tigeciclina/farmacologia , beta-Lactamases/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-30061293

RESUMO

The monobactam scaffold is attractive for the development of new agents to treat infections caused by drug-resistant Gram-negative bacteria because it is stable to metallo-ß-lactamases (MBLs). However, the clinically used monobactam aztreonam lacks stability to serine ß-lactamases (SBLs) that are often coexpressed with MBLs. LYS228 is stable to MBLs and most SBLs. LYS228 bound purified Escherichia coli penicillin binding protein 3 (PBP3) similarly to aztreonam (derived acylation rate/equilibrium dissociation constant [k2/Kd ] of 367,504 s-1 M-1 and 409,229 s-1 M-1, respectively) according to stopped-flow fluorimetry. A gel-based assay showed that LYS228 bound mainly to E. coli PBP3, with weaker binding to PBP1a and PBP1b. Exposing E. coli cells to LYS228 caused filamentation consistent with impaired cell division. No single-step mutants were selected from 12 Enterobacteriaceae strains expressing different classes of ß-lactamases at 8× the MIC of LYS228 (frequency, <2.5 × 10-9). At 4× the MIC, mutants were selected from 2 of 12 strains at frequencies of 1.8 × 10-7 and 4.2 × 10-9 LYS228 MICs were ≤2 µg/ml against all mutants. These frequencies compared favorably to those for meropenem and tigecycline. Mutations decreasing LYS228 susceptibility occurred in ramR and cpxA (Klebsiella pneumoniae) and baeS (E. coli and K. pneumoniae). Susceptibility of E. coli ATCC 25922 to LYS228 decreased 256-fold (MIC, 0.125 to 32 µg/ml) after 20 serial passages. Mutants accumulated mutations in ftsI (encoding the target, PBP3), baeR, acrD, envZ, sucB, and rfaI These results support the continued development of LYS228, which is currently undergoing phase II clinical trials for complicated intraabdominal infection and complicated urinary tract infection (registered at ClinicalTrials.gov under identifiers NCT03377426 and NCT03354754).


Assuntos
Antibacterianos/farmacologia , Escherichia coli/enzimologia , Escherichia coli/genética , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Monobactamas/farmacologia , Aztreonam/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mutação/genética , beta-Lactamases/genética
7.
Bioorg Med Chem Lett ; 28(4): 748-755, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29336873

RESUMO

Metallo-ß-lactamases (MBLs), such as New Delhi metallo-ß-lactamase (NDM-1) have spread world-wide and present a serious threat. Expression of MBLs confers resistance in Gram-negative bacteria to all classes of ß-lactam antibiotics, with the exception of monobactams, which are intrinsically stable to MBLs. However, existing first generation monobactam drugs like aztreonam have limited clinical utility against MBL-expressing strains because they are impacted by serine ß-lactamases (SBLs), which are often co-expressed in clinical isolates. Here, we optimized novel monobactams for stability against SBLs, which led to the identification of LYS228 (compound 31). LYS228 is potent in the presence of all classes of ß-lactamases and shows potent activity against carbapenem-resistant isolates of Enterobacteriaceae (CRE).


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Monobactamas/farmacologia , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamases/metabolismo , Animais , Antibacterianos/efeitos adversos , Antibacterianos/química , Antibacterianos/metabolismo , Aztreonam/farmacologia , Células CHO , Cricetulus , Estabilidade de Medicamentos , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Meropeném , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monobactamas/efeitos adversos , Monobactamas/química , Monobactamas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Convulsões/induzido quimicamente , Relação Estrutura-Atividade , Tienamicinas/farmacologia
8.
Antimicrob Agents Chemother ; 59(3): 1435-40, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25534727

RESUMO

Clostridium difficile infection causes serious diarrheal disease. Although several drugs are available for treatment, including vancomycin, recurrences remain a problem. LFF571 is a semisynthetic thiopeptide with potency against C. difficile in vitro. In this phase 2 exploratory study, we compared the safety and efficacy (based on a noninferiority analysis) of LFF571 to those of vancomycin used in adults with primary episodes or first recurrences of moderate C. difficile infection. Patients were randomized to receive 200 mg of LFF571 or 125 mg of vancomycin four times daily for 10 days. The primary endpoint was the proportion of clinical cures at the end of therapy in the per-protocol population. Secondary endpoints included clinical cures at the end of therapy in the modified intent-to-treat (mITT) population, the time to diarrhea resolution, and the recurrence rate. Seventy-two patients were randomized, with 46 assigned to receive LFF571. Based on the protocol-specified definition, the rate of clinical cure for LFF571 (90.6%) was noninferior to that of vancomycin (78.3%). The 30-day sustained cure rates for LFF571 and vancomycin were 56.7% and 65.0%, respectively, in the per-protocol population and 58.7% and 60.0%, respectively, in the modified intent-to-treat population. Using toxin-confirmed cases only, the recurrence rates were lower for LFF571 (19% versus 25% for vancomycin in the per-protocol population). LFF571 was generally safe and well tolerated. The incidence of adverse events (AEs) was higher for LFF571 (76.1% versus 69.2% for vancomycin), although more AEs in the vancomycin group were suspected to be related to the study drug (38.5% versus 32.6% for LFF571). One patient receiving LFF571 discontinued the study due to an AE. (This study has been registered at ClinicalTrials.gov under registration no. NCT01232595.).


Assuntos
Antibacterianos/uso terapêutico , Clostridioides difficile/efeitos dos fármacos , Infecções por Clostridium/tratamento farmacológico , Tiazóis/uso terapêutico , Vancomicina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tiazóis/efeitos adversos , Vancomicina/efeitos adversos
9.
Antimicrob Agents Chemother ; 56(3): 1584-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22203585

RESUMO

TD-1792 is a new multivalent glycopeptide-cephalosporin antibiotic with potent activity against Gram-positive bacteria. The in vitro activity of TD-1792 was tested against 527 Staphylococcus aureus isolates, including multidrug-resistant isolates. TD-1792 was highly active against methicillin-susceptible S. aureus (MIC(90), 0.015 µg/ml), methicillin-resistant S. aureus, and heterogeneous vancomycin-intermediate S. aureus (MIC(90), 0.03 µg/ml). Time-kill studies demonstrated the potent bactericidal activity of TD-1792 at concentrations of ≤ 0.12 µg/ml. A postantibiotic effect of >2 h was observed after exposure to TD-1792.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Glicopeptídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/química , Cefalosporinas/química , Contagem de Colônia Microbiana , Farmacorresistência Bacteriana Múltipla , Glicopeptídeos/química , Humanos , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Vancomicina/farmacologia
10.
Antimicrob Agents Chemother ; 56(3): 1578-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22155835

RESUMO

TD-1792 is a novel glycopeptide-cephalosporin heterodimer investigational antibiotic that displays potent bactericidal effects against clinically relevant Gram-positive organisms in vitro. The present studies evaluated the in vivo pharmacokinetics (PK) and pharmacodynamics (PD) of TD-1792 in the neutropenic murine thigh infection animal model. TD-1792, dosed subcutaneously (SC), produced dose-dependent reduction in the thigh bacterial burden of several organisms, including methicillin-susceptible and -resistant strains of Staphylococcus aureus and Staphylococcus epidermidis (MSSA, MRSA, MSSE, MRSE, respectively), penicillin-susceptible strains of Streptococcus pneumoniae (PSSP), Streptococcus pyogenes, and vancomycin-intermediate-susceptible Staphylococcus aureus (VISA). In single-dose efficacy studies, the 1-log(10) CFU kill effective dose (ED(1-log kill)) estimates for TD-1792 ranged from 0.049 to 2.55 mg/kg of body weight administered SC, and the bacterial burden was reduced by up to 3 log(10) CFU/g from pretreatment values. Against S. aureus ATCC 33591 (MRSA), the total 24-h log(10) stasis dose (ED(stasis)) and ED(1-logkill) doses for TD-1792 were 0.53 and 1.11 mg/kg/24 h, respectively, compared to 23.4 and 54.6 mg/kg/24 h for vancomycin, indicating that TD-1762 is 44- to 49-fold more potent than vancomycin. PK-PD analysis of data from single-dose and dose-fractionation studies for MRSA (ATCC 33591) demonstrated that the total-drug 24-h area under the concentration-time curve-to-MIC ratio (AUC/MIC ratio) was the best predictor of efficacy (r(2) = 0.826) compared to total-drug maximum plasma concentration of drug-to-MIC ratio (Cmax/MIC ratio; r(2) = 0.715) and percent time that the total-drug plasma drug concentration remains above the MIC (%Time>MIC; r(2) = 0.749). The magnitudes of the total-drug AUC/MIC ratios associated with net bacterial stasis, a 1-log(10) CFU reduction from baseline and near maximal effect, were 21.1, 37.2, and 51.8, respectively. PK-PD targets based on such data represent useful inputs for analyses to support dose selection decisions for clinical studies of patients.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Glicopeptídeos/farmacologia , Neutropenia/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estreptocócicas/tratamento farmacológico , Vancomicina/farmacologia , Animais , Antibacterianos/sangue , Antibacterianos/química , Área Sob a Curva , Cefalosporinas/sangue , Cefalosporinas/química , Contagem de Colônia Microbiana , Dimerização , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Glicopeptídeos/sangue , Glicopeptídeos/química , Humanos , Injeções Subcutâneas , Camundongos , Testes de Sensibilidade Microbiana , Neutropenia/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/crescimento & desenvolvimento , Coxa da Perna/microbiologia , Vancomicina/sangue
11.
ACS Infect Dis ; 7(5): 959-968, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33822577

RESUMO

Cryptosporidiosis is a leading cause of moderate-to-severe diarrhea in low- and middle-income countries, responsible for high mortality in children younger than two years of age, and it is also strongly associated with childhood malnutrition and growth stunting. There is no vaccine for cryptosporidiosis and existing therapeutic options are suboptimal to prevent morbidity and mortality in young children. Recently, novel therapeutic agents have been discovered through high-throughput phenotypic and target-based screening strategies, repurposing malaria hits, etc., and these agents have a promising preclinical in vitro and in vivo anti-Cryptosporidium efficacy. One key step in bringing safe and effective new therapies to young vulnerable children is the establishment of some prospect of direct benefit before initiating pediatric clinical studies. A Cryptosporidium controlled human infection model (CHIM) in healthy adult volunteers can be a robust clinical proof of concept model for evaluating novel therapeutics. CHIM could potentially accelerate the development path to pediatric studies by establishing the safety of a proposed pediatric dosing regimen and documenting preliminary efficacy in adults. We present, here, perspectives regarding the opportunities and perceived challenges with the Cryptosporidium human challenge model.


Assuntos
Criptosporidiose , Cryptosporidium , Malária , Adulto , Antiparasitários/farmacologia , Criança , Pré-Escolar , Criptosporidiose/tratamento farmacológico , Diarreia/tratamento farmacológico , Humanos
12.
J Med Chem ; 64(9): 6329-6357, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33929852

RESUMO

Herein, we describe the discovery and optimization of a novel series that inhibits bacterial DNA gyrase and topoisomerase IV via binding to, and stabilization of, DNA cleavage complexes. Optimization of this series led to the identification of compound 25, which has potent activity against Gram-positive bacteria, a favorable in vitro safety profile, and excellent in vivo pharmacokinetic properties. Compound 25 was found to be efficacious against fluoroquinolone-sensitive Staphylococcus aureus infection in a mouse thigh model at lower doses than moxifloxacin. An X-ray crystal structure of the ternary complex formed by topoisomerase IV from Klebsiella pneumoniae, compound 25, and cleaved DNA indicates that this compound does not engage in a water-metal ion bridge interaction and forms no direct contacts with residues in the quinolone resistance determining region (QRDR). This suggests a structural basis for the reduced impact of QRDR mutations on antibacterial activity of 25 compared to fluoroquinolones.


Assuntos
Antibacterianos/farmacologia , DNA Girase/metabolismo , DNA Topoisomerase IV/antagonistas & inibidores , Desenho de Fármacos , Fluoroquinolonas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Inibidores da Topoisomerase II/farmacologia , Animais , Antibacterianos/química , Farmacorresistência Bacteriana/efeitos dos fármacos , Camundongos , Inibidores da Topoisomerase II/química
13.
Antimicrob Agents Chemother ; 54(7): 2814-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20404117

RESUMO

Telavancin is a bactericidal, semisynthetic lipoglycopeptide indicated in the United States for the treatment of complicated skin and skin structure infections caused by susceptible gram-positive bacteria and is under investigation as a once-daily treatment for nosocomial pneumonia. The related vanA and vanB gene clusters mediate acquired resistance to glycopeptides in enterococci by remodeling the dipeptide termini of peptidoglycan precursors from D-alanyl-D-alanine (D-Ala-D-Ala) to D-alanyl-D-lactate (D-Ala-D-Lac). In this study, we assessed the ability of telavancin to induce the expression of van genes in VanA- and VanB-type strains of vancomycin-resistant enterococci. Vancomycin, teicoplanin, and telavancin efficiently induced VanX activity in VanA-type strains, while VanX activity in VanB-type isolates was inducible by vancomycin but not by teicoplanin or telavancin. In VanA-type strains treated with vancomycin or telavancin, high levels of D-Ala-D-Lac-containing pentadepsipeptide were measured, while D-Ala-D-Ala pentapeptide was present at very low levels or not detected at all. In VanB-type strains, vancomycin but not telavancin induced high levels of pentadepsipeptide, while pentapeptide was not detected. Although vancomycin, teicoplanin, and telavancin induced similar levels of VanX activity in VanA-type strains, these organisms were more sensitive to telavancin, which displayed MIC values that were 32- and 128-fold lower than those of vancomycin and teicoplanin, respectively.


Assuntos
Aminoglicosídeos/farmacologia , Proteínas de Bactérias/metabolismo , Carbono-Oxigênio Ligases/metabolismo , Enterococcus/efeitos dos fármacos , Enterococcus/metabolismo , Óperon/efeitos dos fármacos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Western Blotting , Carbono-Oxigênio Ligases/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterococcus/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/genética , Lipoglicopeptídeos , Óperon/genética , Teicoplanina/farmacologia , Vancomicina/farmacologia , Resistência a Vancomicina/efeitos dos fármacos , Resistência a Vancomicina/genética
14.
J Antimicrob Chemother ; 65(4): 725-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20139142

RESUMO

OBJECTIVES: Infections caused by heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) are associated with high rates of vancomycin treatment failure. Telavancin is a bactericidal lipoglycopeptide active in vitro against Gram-positive pathogens including hVISA and vancomycin-intermediate S. aureus (VISA). This study characterizes the microbiological activity of telavancin against vancomycin-susceptible S. aureus (VSSA), hVISA and VISA strains. METHODS: Reference strains of VSSA, hVISA and VISA were assessed for potential telavancin heteroresistance by population analysis. In addition, the efficacies of telavancin (40 mg/kg subcutaneously every 12 h for 4 days) and vancomycin (110 mg/kg subcutaneously every 12 h for 8 days) were compared in a neutropenic murine model (immunocompromised female non-Swiss albino mice) of bacteraemia caused by hVISA strain Mu3. Blood and spleen bacterial titres were quantified from cohorts of mice euthanized pre-treatment and at 24 h intervals post-treatment for 8 days. RESULTS: Telavancin was active against all strains of S. aureus tested, with MIC values < or =0.5 mg/L. Population analyses revealed no evidence of subpopulations with reduced susceptibility to telavancin. In the murine bacteraemia model of hVISA infection, all animals were bacteraemic pre-treatment and mortality was 100% within 16-24 h post-infection in untreated animals. Treatment with telavancin was associated with lower spleen bacterial titres, lower rates of bacteraemia and lower overall mortality than treatment with vancomycin. CONCLUSIONS: These in vitro and pre-clinical in vivo studies demonstrate that telavancin has the potential to be efficacious in infections caused by hVISA.


Assuntos
Aminoglicosídeos/farmacologia , Aminoglicosídeos/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Resistência a Vancomicina , Aminoglicosídeos/administração & dosagem , Animais , Antibacterianos/administração & dosagem , Bacteriemia/tratamento farmacológico , Sangue/microbiologia , Modelos Animais de Doenças , Feminino , Lipoglicopeptídeos , Camundongos , Testes de Sensibilidade Microbiana , Baço/microbiologia , Resultado do Tratamento
15.
ACS Infect Dis ; 5(7): 1045-1051, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-30861342

RESUMO

Resistance in Gram-negative bacteria to ß-lactam drugs is mediated primarily by the expression of ß-lactamases, and co-dosing of ß-lactams with a ß-lactamase inhibitor (BLI) is a clinically proven strategy to address resistance. New ß-lactamases that are not impacted by existing BLIs are spreading and creating the need for development of novel broader spectrum BLIs. IID572 is a novel broad spectrum BLI of the diazabicyclooctane (DBO) class that is able to restore the antibacterial activity of piperacillin against piperacillin/tazobactam-resistant clinical isolates. IID572 is differentiated from other DBOs by its broad inhibition of ß-lactamases and the lack of intrinsic antibacterial activity.


Assuntos
Compostos Azabicíclicos/síntese química , Bactérias Gram-Negativas/efeitos dos fármacos , Inibidores de beta-Lactamases/síntese química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Compostos Azabicíclicos/química , Compostos Azabicíclicos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Estabilidade de Medicamentos , Bactérias Gram-Negativas/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Inibidores de beta-Lactamases/química , Inibidores de beta-Lactamases/farmacologia
16.
Bioorg Med Chem Lett ; 18(8): 2645-8, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18359228

RESUMO

The synthesis and evaluation of novel azetidine lincosamides 1 are described. Eleven new (3-trans-alkyl)azetidine-2-carboxylic acids were synthesized via alkylation of N-TBS-4-oxo-azetidine-2-carboxylic acid and subsequent elaboration then coupled to 7-chloro-1-methylthio-lincosamine. The resulting lincosamides differ from the drug clindamycin in both the size of the ring and the position/structure of the alkyl side-chain. SAR within the series was explored with attention to alkyl variants in positions 1 and 3 of the azetidine ring.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Azetidinas/química , Macrolídeos/síntese química , Macrolídeos/farmacologia , Antibacterianos/química , Lincosamidas , Macrolídeos/química , Viabilidade Microbiana/efeitos dos fármacos , Estrutura Molecular , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Relação Estrutura-Atividade , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética
17.
PLoS One ; 13(12): e0208449, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30540833

RESUMO

INTRODUCTION: Shared decision making (SDM) is a process whereby decisions are made together by patients and/or families and clinicians. Nevertheless, few patients are aware of its proven benefits. This study investigated the feasibility, acceptability and impact of an intervention to raise public awareness of SDM in public libraries. MATERIALS AND METHODS: A 1.5 hour interactive workshop to be presented in public libraries was co-designed with Quebec City public library network officials, a science communication specialist and physicians. A clinical topic of maximum reach was chosen: antibiotic overuse in treatment of acute respiratory tract infections. The workshop content was designed and a format, whereby a physician presents the information and the science communication specialist invites questions and participation, was devised. The event was advertised to the general public. An evaluation form was used to collect data on participants' sociodemographics, feasibility and acceptability components and assess a potential impact of the intervention. Facilitators held a post-workshop focus group to qualitatively assess feasibility, acceptability and impact. RESULTS: All 10 planned workshops were held. Out of 106 eligible public participants, 89 were included in the analysis. Most participants were women (77.6%), retired (46.1%) and over 45 (59.5%). Over 90% of participants considered the workshop content to be relevant, accessible, and clear. They reported substantial average knowledge gain about antibiotics (2.4, 95% Confidence Interval (CI): 2.0-2.8; P < .001) and about SDM (4.0, 95% CI: 3.4-4.5; P < .001). Self-reported knowledge gain about SDM was significantly higher than about antibiotics (4.0 versus 2.4; P < .001). Knowledge gain did not vary by sociodemographic characteristics. The focus group confirmed feasibility and suggested improvements. CONCLUSIONS: A public library intervention is feasible and effective way to increase public awareness of SDM and could be a new approach to implementing SDM by preparing potential patients to ask for it in the consulting room.


Assuntos
Conscientização , Tomada de Decisões , Bibliotecas , Educação de Pacientes como Assunto/métodos , Participação do Paciente , Encaminhamento e Consulta , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Grupos Focais , Humanos , Bibliotecas/organização & administração , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/organização & administração , Participação do Paciente/métodos , Participação do Paciente/psicologia , Percepção , Relações Médico-Paciente , Setor Público/organização & administração , Quebeque , Adulto Jovem
18.
Can Respir J ; 14(8): 480-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18060093

RESUMO

OBJECTIVES: To describe an interactive playing card workshop in the communication of asthma guidelines recommendations, and to assess the initial evaluation of this educational tool by family physicians. DESIGN: Family physicians were invited to participate in the workshop by advertisements or personal contacts. Each physician completed a standardized questionnaire on his or her perception of the rules, content and properties of the card game. SETTING: A university-based continuing medical education initiative. PARTICIPANTS: Primary care physicians. MAIN OUTCOME MEASURES: Physicians' evaluation of the rules, content and usefulness of the program. RESULTS: The game allowed the communication of relevant asthma-related content, as well as experimentation with a different learning format. It also stimulated interaction in a climate of friendly competition. Participating physicians considered the method to be an innovative tool that facilitated reflection, interaction and learning. It generated relevant discussions on how to apply guideline recommendations to current asthma care. CONCLUSIONS: This new, interactive, educational intervention, integrating play and scientific components, was well received by participants. This method may be of value to help integrate current guidelines into current practice, thus facilitating knowledge transfer to caregivers.


Assuntos
Asma/terapia , Educação Médica Continuada/métodos , Medicina de Família e Comunidade/educação , Médicos de Família/educação , Aprendizagem Baseada em Problemas , Asma/fisiopatologia , Comunicação , Humanos , Disseminação de Informação , Educação de Pacientes como Assunto , Jogos e Brinquedos , Guias de Prática Clínica como Assunto
19.
Patient Educ Couns ; 63(3): 380-90, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17010555

RESUMO

OBJECTIVE: To describe primary health care professionals' views on barriers and facilitators for implementing the Ottawa Decision Support Framework (ODSF) in their practice. METHODS: Thirteen focus groups with 118 primary health care professionals were performed. A taxonomy of barriers and facilitators to implementing clinical practice guidelines was used to content-analyse the following sources: reports from each workshop, field notes from the principal investigator and written materials collected from the participants. RESULTS: Applicability of the ODSF to the practice population, process outcome expectation, asking patients about their preferred role in decision making, perception that the ODSF was modifiable, time issues, familiarity with the ODSF and its practicability were the most frequently identified both as barriers as well as facilitators. Forgetting about the ODSF, interpretation of evidence, challenge to autonomy and total lack of agreement with using the ODSF in general were identified only as barriers. Asking about values, health professional's outcome expectation, compatibility with the patient-centered approach or the evidence-based approach, ease of understanding and implementation, and ease of communicating the ODSF were identified only as facilitators. CONCLUSION: These results provide insight on the type of interventions that could be developed in order to implement the ODSF in academic primary care practice. PRACTICE IMPLICATIONS: Interventions to implement the ODSF in primary care practice will need to address a broad range of factors at the levels of the health professionals, the patients and the health care system.


Assuntos
Atitude do Pessoal de Saúde , Tomada de Decisões , Participação do Paciente , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , Adulto , Canadá , Feminino , Grupos Focais , Humanos , Masculino
20.
BMC Res Notes ; 8: 663, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26555569

RESUMO

BACKGROUND: The net benefits of routine breast cancer screening with mammography have been questioned, and there is evidence to indicate that supporting women to make an informed decision about breast cancer screening with mammography is preferable. The aims of this study were to assess the intention of family physicians to provide women with this support and the determinants of this intention, and to identify factors that might influence family physicians adopting this behavior. METHODS: Family physicians from the province of Quebec, Canada, attending a 45-min lecture on informed decision making and cancer screening were asked to complete a questionnaire after the lecture regarding their intention to adopt the behavior. The questions, based on the Theory of Planned Behavior, measured physicians' intention and its determinants (attitude, perceived behavioral control, and socio-professional norm) regarding supporting women to make informed decisions about breast cancer screening with mammography. Open-ended questions were also used to explore complementary factors influencing their intention. RESULTS: Out of 800 questionnaires distributed, 301 (38 %) were returned and 288 were included in data analysis. The mean ± standard deviation and median score for intention were respectively 1.9 ± 1.2 and 2.0 on a 6-point Likert scale (-3 to +3). Perceived behavioral control was the variable most strongly associated with intention (high versus low score, odds ratio = 15.7, 95 % CI 6.7-36.6), followed by attitude (high versus low score, odds ratio = 7.5, 95 % CI 3.3-16.8), then social norm (high versus low score, odds ratio = 5.8, 95 % CI 2.6-12.9). The most-reported barrier to adopting the behavior was time constraints (41 %) while the most-reported facilitator was availability of relevant decision support tools (29 %). CONCLUSIONS: Respondents showed strong intention to support women in informed decision-making about breast cancer screening, the strongest predictor being perceived behavioral control. These results could contribute to training physicians to integrate this behavior into their practices and to designing relevant decision support tools.


Assuntos
Neoplasias da Mama/diagnóstico , Tomada de Decisões , Detecção Precoce de Câncer/métodos , Intenção , Mamografia/métodos , Médicos de Família/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Médicos de Família/psicologia , Quebeque , Inquéritos e Questionários
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