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1.
Pulm Circ ; 13(4): e12320, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38144949

RESUMO

Pulmonary hypertension (PH) is the most severe complication in preterm infants with bronchopulmonary dysplasia (BPD) and associated with significant mortality. Diagnostic and treatment strategies, however, still lack standardization. By the use of a survey study (PH in BPD), we assessed clinical practice (diagnosis, treatment, follow-up) in preterm infants with early postnatal persistent pulmonary hypertension of the newborn (PPHN) as well as at risk for or with established BPD-associated PH between 06/2018 and 10/2020 in two-thirds of all German perinatal centers with >70 very low birthweight infants/year including their cardiology departments and outpatient units. Data were analyzed descriptively by measures of locations and distributional shares. In routine postnatal care, clinical presentation and echocardiography were reported as the main diagnostic modalities to screen for PPHN in preterm infants, whereas biomarkers brain natriuretic peptide/N-terminal pro b-type natriuretic peptide were infrequently used. For PPHN treatment, inhaled nitric oxide was used in varying frequency. The majority of participants agreed to prescribe diuretics and steroids (systemic/inhaled) for infants at risk for or with established BPD-associated PH and strongly agreed on recommending respiratory syncytial virus immunization and the use of home monitoring upon discharge. Reported oxygen saturation targets, however, varied in these patients in in- and outpatient care. The survey reveals shared practices in diagnostic and therapeutic strategies for preterms with PPHN and BPD-associated PH in Germany. Future studies are needed to agree on detailed echo parameters and biomarkers to diagnose and monitor disease next to a much-needed agreement on the use of pulmonary vasodilators, steroids, and diuretics as well as target oxygen saturation levels.

2.
Microorganisms ; 10(3)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35336201

RESUMO

The increasing demand for new and effective antibiotics requires intelligent strategies to obtain a wide range of potential candidates. Laccase-catalyzed reactions have been successfully applied to synthesize new ß-lactam antibiotics and other antibiotics. In this work, laccases from three different origins were used to produce new aminoglycoside antibiotics. Kanamycin, tobramycin and gentamicin were coupled with the laccase substrate 2,5-dihydroxy-N-(2-hydroxyethyl)-benzamide. The products were isolated, structurally characterized and tested in vitro for antibacterial activity against various strains of Staphylococci, including multidrug-resistant strains. The cytotoxicity of these products was tested using FL cells. The coupling products showed comparable and, in some cases, better antibacterial activity than the parent antibiotics in the agar diffusion assay, and they were not cytotoxic. The products protected mice against infection with Staphylococcus aureus, which was lethal to the control animals. The results underline the great potential of laccases in obtaining new biologically active compounds, in this case new antibiotic candidates from the class of aminoglycosides.

3.
AMB Express ; 10(1): 177, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006678

RESUMO

Trametes spec. laccase (EC 1.10.3.2.) mediates the oxidative coupling of 6-aminopenicillanic, 7-aminocephalosporanic, and 7-aminodesacetoxycephalosporanic acid with 2,5-dihydroxybenzoic acid derivatives to form new penicillin and cephalosporin structures, respectively. The heteromolecular hybrid dimers are formed by nuclear amination of the p-hydroquinones with the primary amines and inhibited in vitro the growth of Staphylococcus species, including some multidrug-resistant strains.

4.
Trials ; 21(1): 307, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245508

RESUMO

BACKGROUND: Interstitial lung diseases in children (chILD) are rare and consist of many different entities that affect the parenchyma of the lungs, leading to a chronic lung disease. The natural course of many of these diseases is connected with a high morbidity and significant mortality. Symptomatic treatment consists of oxygen supplementation, adequate nutrition adapted to the high energy demand generated by the disease due to the increased breathing effort required, as well as immunization against respiratory pathogens to prevent exacerbations through respiratory infections. No proven pharmacological treatments are available to date. This placebo-controlled study aims to evaluate the efficacy and safety of the mid-term use of hydroxychloroquine in chILD. METHODS AND DESIGN: The study is an explorative, prospective, randomized, double-blind, placebo-controlled investigation of hydroxychloroquine (HCQ) in chILD. Patients can be included into the trial when diagnosed with a chronic (≥ 3 weeks' duration) diffuse parenchymal lung disease (chILD) (1) genetically defined, (2) histologically defined or (3) diagnosed with idiopathic pulmonary hemorrhage (hemosiderosis). The study contains of two different study blocks, a START and a STOP block, which can be initiated in any sequence. Each patient can participate in each block only once. In the START block subjects are randomized to parallel groups for 4 weeks treatment, then the placebo group is switched to the active drug. In the STOP block, subjects taking HCQ are randomized into parallel groups treated with placebo or HCQ. DISCUSSION: This study is the first international, investigator-initiated, prospective and controlled investigation of a pharmacological treatment in chILD. The block design was selected as it has the advantage of accommodating patients who are initiating or withdrawing from HCQ therapy, thus allowing the participation of those who were previously started on off-label HCQ. The cross-over design and selected outcome parameters enables us to include appropriate numbers of patients of all age groups from neonates to adults suffering from these rare diseases. TRIAL REGISTRATION: This is an exploratory, Phase 2a, randomized, double-blind, placebo-controlled, parallel-group, multinational study investigating the initiation or withdrawal of hydroxychloroquine in subjects with chILD. Study title: Hydroxychloroquine in pediatric ILD: START randomized controlled in parallel groups, then switch placebo to the active drug, and STOP randomized controlled in parallel groups to evaluate the efficacy and safety of hydroxychloroquine (HCQ). Short title: HCQ in pediatric ILD, particularly 4surfdefect. EudraCT, ID: 2013-003714-40. Registered on 2 July 2013. ClinicalTrials.gov, ID: NCT02615938. Registered on 8 November 2015. IZKS trial code: 2013-006; Sponsor: University Hospital, Ludwig-Maximilians University of Munich. Responsible Party: Prof. Dr. med. Matthias Griese, University Hospital, Ludwig-Maximilians University of Munich, Germany.


Assuntos
Hidroxicloroquina/administração & dosagem , Doenças Pulmonares Intersticiais/tratamento farmacológico , Criança , Estudos Cross-Over , Método Duplo-Cego , Humanos , Hidroxicloroquina/efeitos adversos , Internacionalidade , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Respir Res ; 21(1): 73, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32216792

RESUMO

BACKGROUND: Interstitial lung disease (ILD) is a heterogeneous group of mainly chronic lung diseases differing in disease course and prognosis. For most subtypes, evidence on relevance and outcomes of hospitalisations is lacking. METHODS: Using German claims data we investigated number of hospitalisations (zero-inflated-negative-binomial models providing rate ratios (RR)) and time to first hospitalisation (Cox proportional-hazard models providing hazard ratios (RR)) for nine ILD-subtypes. Models were stratified by ILD-related and non-ILD-related hospitalisations. We adjusted for age, gender, ILD-subtype, ILD-relevant comorbidities and ILD-medication (immunosuppressive drugs, steroids, anti-fibrotic drugs). RESULTS: Among 36,816 ILD-patients (mean age 64.7 years, 56.2% male, mean observation period 9.3 quarters), 71.2% had non-ILD-related and 56.6% ILD-related hospitalisations. We observed more and earlier non-ILD-related hospitalisations in ILD patients other than sarcoidosis. Medical ILD-treatment was associated with increased frequency and in case of late initiation, earlier (non-)ILD-related hospitalisations. Comorbidities were associated with generally increased hospitalisation frequency except for COPD (RR = 0.90) and PH (RR = 0.94) in non-ILD-related and for lung cancer in ILD-related hospitalisations (RR = 0.89). Coronary heart disease was linked with earlier (ILD-related: HR = 1.17, non-ILD-related HR = 1.19), but most other conditions with delayed hospitalisations. CONCLUSION: Hospitalisations are frequent across all ILD-subtypes. The hospitalisation risk might be reduced independently of the subtype by improved management of comorbidities and improved pharmacological and non-pharmacological ILD therapy.


Assuntos
Hospitalização/estatística & dados numéricos , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/patologia , Comorbidade , Análise de Dados , Progressão da Doença , Feminino , Humanos , Doenças Pulmonares Intersticiais/classificação , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais
6.
Respir Res ; 20(1): 47, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823880

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a rare disease with a median survival of 3-5 years after diagnosis with limited treatment options. The aim of this study is to assess the psychometric characteristics of the Short Form 36 Health Status Questionnaire (SF-36) in IPF and to provide disease specific minimally important differences (MID). METHODS: Data source was the European IPF Registry (eurIPFreg). The psychometric properties of the SF-36 version 2 were evaluated based on objective clinical measures as well as subjective perception. We analysed acceptance, feasibility, discrimination ability, construct and criterion validity, responsiveness and test-retest-reliability. MIDs were estimated via distribution and anchor-based approaches. RESULTS: The study population included 258 individuals (73.3% male; mean age 67.3 years, SD 10.7). Of them 75.2% (194 individuals) had no missing item. The distribution of several items was skewed, although floor effect was acceptable. Physical component score (PCS) correlated significantly and moderately with several anchors, whereas the correlations of mental component score (MCS) and anchors were only small. The tests showed mainly significant lower HRQL in individuals with long-term oxygen therapy. Analyses in stable individuals did not show significant changes of HRQL except for one dimension and anchor. Individuals with relevant changes of the health status based on the anchors had significant changes in all SF-36 dimensions and summary scales except for the dimension PAIN. PCS and MCS had mean MIDs of five and six, respectively. Mean MIDs of the dimensions ranged from seven to 21. CONCLUSION: It seems that the SF-36 is a valid instrument to measure HRQL in IPF and so can be used in RCTs or individual monitoring of disease. Nevertheless, the additional evaluation of longitudinal aspects and MIDs can be recommended to further analyse these factors. Our findings have a great potential impact on the evaluation of IPF patients. TRIAL REGISTRATION: The eurIPFreg and eurIPFbank are listed in https://clinicaltrials.gov ( NCT02951416 ).


Assuntos
Nível de Saúde , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/epidemiologia , Inquéritos e Questionários/normas , Idoso , Estudos Transversais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes
7.
Respir Res ; 19(1): 73, 2018 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-29695236

RESUMO

BACKGROUND: Interstitial lung diseases (ILDs) are associated with a high burden of disease. However, data on the prognostic impact of comorbidities and comorbidity-related pharmaceutical treatments in patients with various ILDs remain sparse. METHODS: Using longitudinal claims data from a German Statutory Health Insurance Fund, we assessed comorbidity in ILD subtypes and associated drug treatments. Baseline comorbidity was assessed via the Elixhauser Comorbidity Index that was amended by ILD-relevant conditions. Drug treatment was assessed on the substance level using the ATC-codes of drugs prescribed at the time of ILD diagnosis. Subsequently, the comorbid conditions (main analysis) and pharmaceutical substances (secondary analysis) with a meaningful association to survival were identified for the complete ILD cohort and within the subtype strata. For this, we applied multivariate Cox models using a LASSO selection process and visualized the findings within comorbidomes. RESULTS: In the 36,821 patients with ILDs, chronic obstructive pulmonary disease (COPD), arterial hypertension, and ischaemic heart disease (IHD) were the most prevalent comorbidities. The majority of patients with cardiovascular diseases received pharmaceutical treatment, while, in other relevant comorbidities, treatment quotas were low (COPD 46%, gastro-oesophageal reflux disease 65%). Comorbidities had a clinically meaningful detrimental effect on survival that tended to be more pronounced in the case of untreated conditions (e.g. hazard ratios for treated IHD 0.97 vs. 1.33 for untreated IHD). Moreover, comorbidity impact varied substantially between distinct subtypes. CONCLUSIONS: Our analyses suggest that comorbid conditions and their treatment profile significantly affect mortality in various ILDs. Therefore, comprehensive comorbidity assessment and management remains important in any ILD.


Assuntos
Formulário de Reclamação de Seguro/tendências , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/terapia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Estatística como Assunto/tendências , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Doenças Pulmonares Intersticiais/diagnóstico , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento
8.
Appl Microbiol Biotechnol ; 100(11): 4885-99, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26780358

RESUMO

The rapidly increasing problem of antimicrobial-drug resistance requires the development of new antimicrobial agents. The laccase-catalyzed amination of dihydroxy aromatics is a new and promising method to enlarge the range of currently available antibiotics. Thirty-eight potential 1,2- and 1,4-hydroquinoid laccase substrates were screened for their antibacterial and cytotoxic activity to select the best substrates for laccase-catalyzed coupling reaction resulting in potent antibacterial derivatives. As a result, methyl-1,4-hydroquinone and 2,3-dimethyl-1,4-hydroquinone were used as parent compounds and 14 novel cephalosporins, penicillins, and carbacephems were synthesized by amination with amino-ß-lactam structures. All purified products were stable in aqueous buffer and resistant to the action of ß-lactamases, and in agar diffusion and broth micro-dilution assays, they inhibited the growth of several Gram-positive bacterial strains including multidrug-resistant Staphylococcus aureus and Enterococci. Their in vivo activity and cytotoxicity in a Staphylococcus-infected, immune-suppressed mouse model are discussed.


Assuntos
Anti-Infecciosos/síntese química , Lacase/metabolismo , beta-Lactamas/síntese química , Animais , Anti-Infecciosos/farmacologia , Biotransformação , Catálise , Cefalosporinas/síntese química , Cefalosporinas/farmacologia , Meios de Cultura/química , Modelos Animais de Doenças , Enterococcus/efeitos dos fármacos , Feminino , Bactérias Gram-Positivas/efeitos dos fármacos , Hidroquinonas/química , Microbiologia Industrial , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Penicilinas/síntese química , Penicilinas/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , beta-Lactamases/química , beta-Lactamases/farmacologia , beta-Lactamas/farmacologia
9.
Biomed Res Int ; 2015: 123876, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26640781

RESUMO

Despite a number of prospective registries conducted in past years, the current epidemiology of interstitial lung diseases (ILD) is still not well defined, particularly regarding the prevalence and incidence, their management, healthcare utilisation needs, and healthcare-associated costs. To address these issues in Germany, a new prospective ILD registry, "Exploring Clinical and Epidemiological Characteristics of Interstitial Lung Diseases" (EXCITING-ILD), is being conducted by the German Centre for Lung Research in association with ambulatory, inpatient, scientific pulmonology organisations and patient support groups. This multicentre, noninterventional, prospective, and observational ILD registry aims to collect comprehensive and validated data from all healthcare institutions on the incidence, prevalence, characteristics, management, and outcomes regarding all ILD presentations in the real-world setting. Specifically, this registry will collect demographic data, disease-related data such as ILD subtype, treatments, diagnostic procedures (e.g., HRCT, surgical lung biopsy), risk factors (e.g., familial ILD), significant comorbidities, ILD managements, and disease outcomes as well as healthcare resource consumption. The EXCITING-ILD registry will include in-patient and out-patient ILD healthcare facilities in more than 100 sites. In summary, this registry will document comprehensive and current epidemiological data as well as important health economic data for ILDs in Germany.


Assuntos
Doenças Pulmonares Intersticiais/epidemiologia , Pulmão/fisiopatologia , Sistema de Registros , Biópsia , Alemanha , Custos de Cuidados de Saúde , Humanos , Doenças Pulmonares Intersticiais/economia , Doenças Pulmonares Intersticiais/fisiopatologia , Pacientes Ambulatoriais , Estudos Prospectivos , Fatores de Risco
10.
Phytochemistry ; 114: 102-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25817834

RESUMO

In contrast to well-studied and broadly used Ganoderma species, such as Ganoderma lucidum and Ganoderma applanatum, knowledge regarding Ganoderma pfeifferi is very limited. Herein is an overview of the phytochemistry, biological activities and possible applications of this mushroom species. In addition to triterpenoids and polysaccharides, G. pfeifferi contains unique sesquiterpenoids and other small molecular weight compounds. Some of these compounds exhibit remarkable antimicrobial activities in vitro and in vivo against multi-resistant bacteria, such as MRSA. Antiviral properties, UV-protection abilities and other activities are also known. Potential issues arising from the conversion of research results into practical applications are discussed.


Assuntos
Ganoderma/química , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Hidroquinonas/química , Hidroquinonas/isolamento & purificação , Hidroquinonas/farmacologia , Queratinócitos/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia
11.
PLoS One ; 9(12): e114720, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25486421

RESUMO

BACKGROUND: Cardiovascular disease is the leading cause of morbidity and mortality in the developed world. To reduce this burden of disease, a German sickness fund ('Siemens-Betriebskrankenkasse', SBK) initiated the prevention programme 'KardioPro' including primary (risk factor reduction) and secondary (screening) prevention and guideline-based treatment. The aim of this study was to assess the effectiveness of 'KardioPro' as it is implemented in the real world. METHODS: The study is based on sickness fund routine data. The control group was selected from non-participants via propensity score matching. Study analysis was based on time-to-event analysis via Cox proportional hazards regression with the endpoint 'all-cause mortality, acute myocardial infarction (MI) and ischemic stroke (1)', 'all-cause mortality (2)' and 'non-fatal acute MI and ischemic stroke (3)'. RESULTS: A total of 26,202 insurants were included, 13,101 participants and 13,101 control subjects. 'KardioPro' enrollment was associated with risk reductions of 23.5% (95% confidence interval (CI) 13.0-32.7%) (1), 41.7% (95% CI 30.2-51.2%) (2) and 3.5% (hazard ratio 0.965, 95% CI 0.811-1.148) (3). This corresponds to an absolute risk reduction of 0.29% (1), 0.31% (2) and 0.03% (3) per year. CONCLUSION: The prevention programme initiated by a German statutory sickness fund appears to be effective with regard to all-cause mortality. The non-significant reduction in non-fatal events might result from a shift from fatal to non-fatal events.


Assuntos
Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Interpretação Estatística de Dados , Pessoal de Saúde/normas , Prevenção Primária , Avaliação de Programas e Projetos de Saúde , Estudos de Casos e Controles , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Seguro Saúde , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo
12.
BMC Health Serv Res ; 14: 263, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24938674

RESUMO

BACKGROUND: Cardiovascular diseases are the main cause of death worldwide, making their prevention a major health care challenge. In 2006, a German statutory health insurance company presented a novel individualised prevention programme (KardioPro), which focused on coronary heart disease (CHD) screening, risk factor assessment, early detection and secondary prevention. This study evaluates KardioPro in CHD risk subgroups, and analyses the cost-effectiveness of different individualised prevention strategies. METHODS: The CHD risk subgroups were assembled based on routine data from the statutory health insurance company, making use of a quasi-beta regression model for risk prediction. The control group was selected via propensity score matching based on logistic regression and an approximate nearest neighbour approach. The main outcome was cost-effectiveness. Effectiveness was measured as event-free time, and events were defined as myocardial infarction, stroke and death. Incremental cost-effectiveness ratios comparing participants with non-participants were calculated for each subgroup. To assess the uncertainty of results, a bootstrapping approach was applied. RESULTS: The cost-effectiveness of KardioPro in the group at high risk of CHD was € 20,901 per event-free year; in the medium-risk group, € 52,323 per event-free year; in the low-risk group, € 186,074 per event-free year; and in the group with known CHD, € 26,456 per event-free year. KardioPro was associated with a significant health gain but also a significant cost increase. However, statistical significance could not be shown for all subgroups. CONCLUSION: The cost-effectiveness of KardioPro differs substantially according to the group being targeted. Depending on the willingness-to-pay, it may be reasonable to only offer KardioPro to patients at high risk of further cardiovascular events. This high-risk group could be identified from routine statutory health insurance data. However, the long-term consequences of KardioPro still need to be evaluated.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Seguradoras , Prevenção Primária/economia , Adulto , Análise Custo-Benefício , Diagnóstico Precoce , Feminino , Alemanha , Humanos , Masculino , Programas de Rastreamento/economia , Avaliação de Programas e Projetos de Saúde , Pontuação de Propensão , Medição de Risco/economia , Prevenção Secundária/economia
13.
Biosens Bioelectron ; 36(1): 207-11, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22572157

RESUMO

To prevent and treat immune-mediated platelet disorders (e.g. neonatal allo-immune thrombocytopenia and platelet transfusion refractoriness) the causative idiotypic platelet-reactive antibodies have to be detected with high sensitivity and specificity. The "Monoclonal Antibody Immobilization Platelet Assay" (MAIPA) is the diagnostic gold standard for immunotyping sera with respect to alloantibodies against human platelet antigens (HPA). However, it is labor-intensive and time-consuming. In this work, an automated protein chip assay (enzyme-linked sandwich immunoassay) based on interdigitated gold microelectrodes in combination with an electrical read-out system was developed and optimized. For this purpose, specific capture antibodies were immobilized on the gold electrodes. The binding of the target is detected via an enzyme-labeled detection antibody by a redox-recycling process that corresponds to the amount of bound target molecule. With this electrical chip assay it is possible to detect antibodies against HPA-1a, HPA-5b and HLA with high sensitivity and specificity in less than half the duration of the MAIPA protocol with similar intra- and interassay variance.


Assuntos
Anticorpos Monoclonais , Antígenos de Plaquetas Humanas/análise , Técnicas Biossensoriais , Isoanticorpos/análise , Análise Serial de Proteínas , Anticorpos Monoclonais/química , Transtornos Plaquetários/diagnóstico , Técnicas Eletroquímicas , Ouro , Antígenos HLA/análise , Humanos , Isoanticorpos/sangue , Microeletrodos , Análise Serial de Proteínas/métodos , Sensibilidade e Especificidade , Trombocitopenia/diagnóstico
14.
Biotechnol Appl Biochem ; 59(4): 295-306, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586863

RESUMO

Seven novel ß-lactam antibiotics with activities against Gram-positive bacterial strains, among them methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, were synthesized by amination of 2,5-dihydroxyphenylacetic acid in usable yields (30-60%). These products protected mice against an infection with S. aureus lethal to the control animals. The results show the usefulness of laccase for the synthesis of potential new antibiotics, in addition to the interdependence of the laccase substrates, the amino coupling partners, and the product formation, yield, and activity. The syntheses of ß-lactam antibiotics with 2,5-dihydroxyaromatic acid substructures (para-substituted) are then compared with those of 3,4-dihydroxyaromatic acid substructures (ortho-substituted). Para-substituted laccase substrates were better reaction partners in these syntheses than ortho-substituted compounds.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Biocatálise , Lacase/metabolismo , beta-Lactamas/síntese química , beta-Lactamas/farmacologia , Aminação , Animais , Bactérias/efeitos dos fármacos , Benzeno/química , Benzeno/metabolismo , Biotransformação , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Sordariales/enzimologia
15.
Chem Pharm Bull (Tokyo) ; 56(7): 902-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18591799

RESUMO

Novel cephalosporins, penicillins, and carbacephems were synthesized by amination of catechols with amino-beta-lactams like cefadroxil, amoxicillin, ampicillin and the structurally related carbacephem loracarbef using laccase from Trametes sp. All isolated monoaminated products inhibited the growth of several Gram positive bacterial strains in the agar diffusion assay, among them methicillin-resistant Staphylococcus aureus strains and vancomycin-resistant Enterococci. Observed differences in the cytotoxicity and in vivo activity in a "Staphylococcus-infected, immune suppressed mouse" model are discussed.


Assuntos
Antibacterianos/síntese química , Catecóis/química , Lacase/metabolismo , beta-Lactamas/síntese química , Aminação , Antibacterianos/farmacologia , Catálise , Fungos/enzimologia , Relação Estrutura-Atividade , beta-Lactamas/farmacologia
16.
Chem Pharm Bull (Tokyo) ; 55(3): 412-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17329882

RESUMO

Sixteen novel cephalosporins were synthesized by amination of 2,5-dihydroxybenzoic acid derivatives with the aminocephalosporins cefadroxil, cefalexin, cefaclor, and the structurally related carbacephem loracarbef using laccases from Trametes sp. or Myceliophthora thermophila. All products inhibited the growth of several Gram positive bacterial strains in the agar diffusion assay, among them methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. The products protected mice against an infection with Staphylococcus aureus lethal to the control animals. Cytotoxicity and acute toxicity of the new compounds were negligible. The results show the usefulness of laccase for the synthesis of potential new antibiotics. The biological activity of the new compounds stimulates intensified pharmacological tests.


Assuntos
Cefalosporinas/síntese química , Fungos/enzimologia , Gentisatos/química , Lacase/metabolismo , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ciclofosfamida , Farmacorresistência Bacteriana Múltipla , Feminino , Hospedeiro Imunocomprometido , Imunossupressores , Lacase/química , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estafilocócicas/tratamento farmacológico
17.
Chem Pharm Bull (Tokyo) ; 54(5): 632-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16651757

RESUMO

Eight novel penicillins were synthesized by heteromolecular reaction of ampicillin or amoxicillin with 2,5-dihydroxybenzoic acid derivatives using a laccase from Trametes spec. All products inhibited the growth of several gram positive bacterial strains in the agar diffusion assay, among them methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. The products protected mice against an infection with Staphylococcus aureus lethal to the untreated animals. Cytotoxicity and acute toxicity of the new compounds were neglectable. The results show the usefulness of laccase for the synthesis of potential new antibiotics. The biological activity of the new compounds stimulates intensified pharmacological tests.


Assuntos
Basidiomycota/metabolismo , Lacase/metabolismo , Penicilinas/biossíntese , Animais , Antibióticos Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Feminino , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Inibidores de beta-Lactamases , beta-Lactamases/metabolismo
18.
ALTEX ; 13(5): 76-77, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-11178479

RESUMO

The aim of this study was the production of specific IgY against cell-associated, highly conserved mammalian proteins. CD 14 is expressed on monocyte surfaces and was identified as endotoxin receptor. P 23 is a cellular protein with unclear biological function. The induction, preparation and characterization of egg yolk antibodies against these antigens are described.

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