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1.
Antimicrob Agents Chemother ; 67(4): e0146222, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36892306

RESUMO

The clinical involvement and antifungal susceptibility of Aspergillus section Circumdati are poorly known. We analyzed 52 isolates, including 48 clinical isolates, belonging to 9 species inside the section Circumdati. The whole section exhibited, by the EUCAST reference method, a poor susceptibility to amphotericin B, but species/series-specific patterns were observed for azole drugs. This underlines the interest in getting an accurate identification inside the section Circumdati to guide the choice of antifungal treatment in clinical practice.


Assuntos
Antifúngicos , Aspergillus , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Anfotericina B/farmacologia , Azóis/farmacologia
2.
Appl Opt ; 60(31): H1-H11, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807139

RESUMO

In this paper, we review practical limitations to laser space propulsion that have been discussed in the literature. These are as follows: (1) thermal coupling to the propelled payload, which might melt it; (2) a decrease in mechanical coupling with number of pulses, which has been observed in some cases; and (3) destruction of solar panels in debris removal proposals that might create more debris rather than less. Previously, lack of data prevented definite assessments. Now, new data on multipulse vacuum laser impulse coupling coefficient Cm on several materials at 1064 nm, at 1030 nm, and at 532 nm are available. We are now able to compare the results for single and multiple pulses on materials that have been considered for laser ablation space propulsion (LASP), or that are likely space debris constituents, and decide whether LASP is a practical idea. Laser space propulsion and debris removal concepts depend on thousands or hundreds of thousands of repetitive pulses. Repetitive pulse mechanical coupling as well as thermal coupling (which can melt the target rather than propel it) are both important considerations. Materials studied were 6061T6 aluminum, carbon-doped polyoxymethylene (POM), undoped POM, a yellow POM copolymer, and a mixture of Al and POM microparticles combined and pressed, containing a 50%/50% mixture of the two materials by mass. We address 6 and 70 ps pulses because of the availability of data at these pulse durations. We also briefly consider continuous wave (CW) laser propulsion. Finally, we consider a recent paper concerning solar panel destruction from a positive perspective.

3.
Antimicrob Agents Chemother ; 64(12)2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-32900686

RESUMO

The antifungal susceptibility of Aspergillus cryptic species is poorly known. We assessed 51 isolates, belonging to seven Fumigati cryptic species, by the EUCAST reference method and the concentration gradient strip (CGS) method. Species-specific patterns were observed, with high MICs for azole drugs, except for Aspergillus hiratsukae and Aspergillus tsurutae, and high MICs for amphotericin B for Aspergillus lentulus and Aspergillus udagawae Essential and categorical agreements between EUCAST and CGS results were between 53.3 and 93.3%.


Assuntos
Antifúngicos , Aspergillus , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Testes de Sensibilidade Microbiana
4.
J Mycol Med ; 30(2): 100970, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32334948

RESUMO

A survey of mycology laboratories for antifungal susceptibility testing (AFST) was undertaken in France in 2018, to better understand the difference in practices between the participating centers and to identify the difficulties they may encounter as well as eventual gaps with published standards and guidelines. The survey captured information from 45 mycology laboratories in France on how they perform AFST (number of strains tested, preferred method, technical and quality aspects, interpretation of the MIC values, reading and interpretation difficulties). Results indicated that 86% of respondents used Etest as AFST method, with a combination of one to seven antifungal agents tested. Most of the participating laboratories used similar technical parameters to perform their AFST method and a large majority used, as recommended, internal and external quality assessments. Almost all the participating mycology laboratories (98%) reported difficulties to interpret the MIC values, especially when no clinical breakpoints are available. The survey highlighted that the current AFST practices in France need homogenization, particularly for MIC reading and interpretation.


Assuntos
Antifúngicos/uso terapêutico , Laboratórios , Testes de Sensibilidade Microbiana , Micologia , Prática Profissional/estatística & dados numéricos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/estatística & dados numéricos , Farmacorresistência Fúngica , França , História do Século XXI , Humanos , Laboratórios/normas , Laboratórios/estatística & dados numéricos , Ensaio de Proficiência Laboratorial/métodos , Ensaio de Proficiência Laboratorial/estatística & dados numéricos , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Micologia/história , Micologia/métodos , Micologia/normas , Micologia/estatística & dados numéricos , Prática Profissional/normas , Controle de Qualidade , Inquéritos e Questionários
5.
Artigo em Inglês | MEDLINE | ID: mdl-29439956

RESUMO

Aspergillus section Terrei is a species complex currently comprised of 14 cryptic species whose prevalence in clinical samples as well as antifungal susceptibility are poorly known. The aims of this study were to investigate A. Terrei clinical isolates at the species level and to perform antifungal susceptibility analyses by reference and commercial methods. Eighty-two clinical A. Terrei isolates were collected from 8 French university hospitals. Molecular identification was performed by sequencing parts of beta-tubulin and calmodulin genes. MICs or minimum effective concentrations (MECs) were determined for 8 antifungal drugs using both EUCAST broth microdilution (BMD) methods and concentration gradient strips (CGS). Among the 79 A. Terrei isolates, A. terreus stricto sensu (n = 61), A. citrinoterreus (n = 13), A. hortai (n = 3), and A. alabamensis (n = 2) were identified. All strains had MICs of ≥1 mg/liter for amphotericin B, except for two isolates (both A. hortai) that had MICs of 0.25 mg/liter. Four A. terreus isolates were resistant to at least one azole drug, including one with pan-azole resistance, yet no mutation in the CYP51A gene was found. All strains had low MECs for the three echinocandins. The essential agreements (EAs) between BMD and CGS were >90%, except for those of amphotericin B (79.7%) and itraconazole (73.4%). Isolates belonging to the A section Terrei identified in clinical samples show wider species diversity beyond the known A. terreus sensu stricto Azole resistance inside the section Terrei is uncommon and is not related to CYP51A mutations here. Finally, CGS is an interesting alternative for routine antifungal susceptibility testing.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Aspergillus/genética , Anfotericina B/farmacologia , Azóis/farmacologia , Equinocandinas/farmacologia , Humanos , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana
6.
Med Mal Infect ; 45(3): 84-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25676476

RESUMO

PURPOSE: Surveillance of preventable healthcare associated infections and feedback of the results to clinicians is central in the efforts to improve performance. We assessed Staphylococcus aureus healthcare associated bloodstream infection (HA-BSI) as an indicator of healthcare quality. PATIENTS AND METHOD: Between 2002 and 2012, we carried out a ten-year prospective bedside surveillance of S. aureus healthcare associated bacteraemia in a 940-bed university hospital using standard definitions. RESULTS: Overall, 2784 HA-BSI were identified during the study period, among which 573 (18%) were due to S. aureus. Among these 573 S. aureus bacteraemias, 189 originated from intravascular catheters (32.8%) of which 84% (158/189) in patients outside intensive care units. The proportion of catheter related HA-BSI due to S. aureus was 56% (61/109) in PVC-related HA-BSI and 34% (103/301) in CVC-related HA-BSI. A sharp decrease of PVC-related HA-BSI from 20 to 7 per year was obtained during the same period. CONCLUSION: In our experience, S. aureus HA-BSI is a simple and useful indicator of catheter associated infections, and therefore of healthcare quality, especially in units not covered by other type of surveillance.


Assuntos
Bacteriemia/epidemiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecção Hospitalar/epidemiologia , Indicadores de Qualidade em Assistência à Saúde , Infecções Estafilocócicas/epidemiologia , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , Infecção Hospitalar/microbiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Departamentos Hospitalares/estatística & dados numéricos , Unidades Hospitalares/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Especificidade de Órgãos , Paris/epidemiologia , Vigilância da População , Estudos Prospectivos , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação
7.
Eur J Clin Microbiol Infect Dis ; 31(7): 1667-71, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22134774

RESUMO

Hospital antibiotic management teams (AMTs) have been recommended, but, in France, their concrete implementation remains scarce and their effectiveness largely unevaluated. The objective of this investigation was to evaluate the appropriateness of antibiotic therapy (AT) for bloodstream infections (BSIs) at a 950-bed university teaching hospital, and assess the role of an AMT in improving it. A prospective analysis of all significant BSIs occurring outside of the intensive care unit (ICU) during an 18-month period was carried out. AT was deemed effective if at least one prescribed antibiotic was effective in vitro, and appropriate if it was consistent with local recommendations. Out of 574 BSIs, 512 were evaluated: 231 community-acquired, 206 nosocomial, and 75 healthcare-associated. For 219 (42.8%) BSIs, the AT initiated prior to AMT intervention proved to be effective and appropriate, inappropriate but effective in 136 (26.5%), and ineffective or absent in 157 (30.7%). In the multivariate analysis, hospital-acquired and other healthcare-associated BSIs, as well as catheter-borne (CB) infections, were associated with inappropriate or absent AT. A recommendation from the AMT was given and followed in 233 (94%) out of 249 BSIs requiring intervention. Initially, two-thirds of BSIs outside the ICU did not receive appropriate AT. Healthcare-associated BSIs should, therefore, be the priority target of AMTs.


Assuntos
Antibacterianos/administração & dosagem , Bacteriemia/tratamento farmacológico , Tratamento Farmacológico/métodos , Tratamento Farmacológico/normas , Uso de Medicamentos/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Feminino , França , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Política Organizacional , Estudos Prospectivos , Resultado do Tratamento
8.
Med Mal Infect ; 40(11): 637-43, 2010 Nov.
Artigo em Francês | MEDLINE | ID: mdl-20650583

RESUMO

INTRODUCTION: Antibiotic management teams (AMTs) are recommended, but they are rarely implemented in France and their activity seldom evaluated. OBJECTIVE: The study was made to evaluate the appropriateness of antibiotic therapy (AT) for bloodstream infections (BSI) and to assess the role of an AMT for improving AT in a 950-bed teaching hospital. METHODS: A prospective analysis was made of all significant BSIs outside ICU in 2008. AT was assessed by the AMT and change was suggested if deemed necessary: effective if at least one prescribed antibiotic was effective in vitro, and appropriate if consistent with local recommendations. RESULTS: Of 875 +BCs, 560 were significant, 383 were outside ICU and 344 could be evaluated (170 community-acquired, 124 nosocomial, and 50 healthcare-associated [HCA]). The clinical ward has already initiated an effective and appropriate AT in 128 (37%), inappropriate but effective in 104 (30%), and ineffective or absent in 112 (33%) BSIs. The only independent variable associated with ineffective/absent AT was nosocomial and/or HCA BSI (aOR: 2.71; 95%CI: 1.72-4.27; p<0.001). A recommendation was given and followed in 177/190 (93%) BSIs requiring an intervention. The AMT intervened on the day of the +BC in 256 (84%) cases, the day before the +BC in 12 (4%) cases, and one day later or more in 37 (12%) BSI cases. CONCLUSION: Two third of BSIs were not initially treated by appropriate AT, more often in nosocomial BSI. Recommendation provided by the AMT was followed in 93% of cases.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Árvores de Decisões , Uso de Medicamentos/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serviço de Farmácia Hospitalar/organização & administração , Estudos Prospectivos
9.
Clin Microbiol Infect ; 16(7): 863-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19778296

RESUMO

In routine laboratory practice, the determination of MICs of antifungals for yeasts often relies on the Etest, because of a good correlation with reference methods. However, this correlation was established through predesigned studies, rather than prospective testing. The surveillance programme of fungaemia (YEASTS programme), implemented since 2003, facilitated our comparison of the Etest and the EUCAST results, obtained on a routine basis in nine different hospitals and in a reference laboratory, respectively. The analysis included 690 isolates recovered from blood culture (362 Candida albicans, 113 Candida glabrata, 69 Candida parapsilosis, 55 Candida tropicalis, 31 Cryptococcus neoformans, and 60 other yeast species) that were tested for their susceptibility to amphotericin B (n = 655), fluconazole (n = 669), itraconazole (n = 198), voriconazole (n = 588), flucytosine (n = 314), and caspofungin (n = 244). Agreement between the Etest and EUCAST datasets was calculated and categorized on the basis of previously published breakpoints. The level of agreement at ±2 dilutions was 75% for amphotericin B and 90% for flucytosine; for the azoles, it ranged from 71% for itraconazole to 87% for voriconazole. No significant difference was observed among the yeast species, except for Cryptococcus neoformans and flucytosine, with an agreement <40%. Categorical agreement ranged from 60% for itraconazole to 90% for flucytosine. Major and very major discrepancies occurred in <12% and 6%, respectively. The Etest, even when performed on a routine basis, shows a ≥71% agreement with the EUCAST reference method.


Assuntos
Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Leveduras/efeitos dos fármacos , Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Caspofungina , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/isolamento & purificação , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Fluconazol/farmacologia , Flucitosina/farmacologia , Fungemia , Itraconazol/farmacologia , Laboratórios Hospitalares , Lipopeptídeos , Pirimidinas/farmacologia , Valores de Referência , Triazóis/farmacologia , Voriconazol
10.
Mar Biotechnol (NY) ; 3(2): 172-80, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14961380

RESUMO

All during fish postmortem evolution, structural muscle proteins are targets for various proteases. During the prerigor period (24 hours at 4 degrees C for sea bass), cytoskeletal proteins are affected by the first proteolytic events. These cleavages disrupt connections between myofibrils and the extracellular matrix, induce segmentation of myofibril cores, and modify the rheological properties of tissue. Dystrophin, a cytoskeletal actin-binding protein, is a relevant in situ marker for muscular proteolysis in the prerigor period. The immunodetection of dystrophin allowed the monitoring of early proteolysis during fish storage. Using antidystrophin antibodies directed toward the carboxy-terminal region, a highly sensitive domain exposed to calpain activity, we showed that proteolysis kinetics are strongly influenced by the muscular lipid content. In particular, comparison between low-fat diets (11.3% lipid) and high-fat diets (30% lipid), used during sea bass farming (90 days), revealed a faster proteolysis rate during the first 8 hours of storage at 0 degrees C with the high-fat diet. The origin of this faster proteolysis is discussed on the basis of a possible activation or translocation of calpains related to lipid accumulation in muscle fibers and cytoskeleton alterations.

11.
Urology ; 55(2): 287-91, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10688097

RESUMO

OBJECTIVES: To investigate the prevalence of the microsatellite instability related to mismatch repair (MMR) gene defects using a panel of six microsatellite markers, as recommended by a recent workshop on microsatellite instability in colon cancer, because it is still unclear whether abnormalities in DNA MMR genes are involved in transitional cell carcinoma (TCC) of the bladder. METHODS: Three mononucleotide repeats (BAT26, TGFbetaRII, and BAX) were studied in 33 TCC samples and in four bladder cancer cell lines. Three dinucleotide repeats (D2S123, D5S346, and D17S250) were studied in 21 of these 33 TCC samples. RESULTS: No alteration was detected either in the 33 TCC samples analyzed or in the four bladder cancer cell lines (T24, J82, 647V, and 1207) studied. A difference between normal and tumor DNA was observed in only 1 of 21 tumor samples for D17S250. CONCLUSIONS: These data indicate that microsatellite instability is very uncommon in TCC of the bladder.


Assuntos
Carcinoma de Células de Transição/genética , Repetições de Microssatélites , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
12.
J Muscle Res Cell Motil ; 20(2): 187-97, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10412090

RESUMO

CapZ is a widely distributed and highly conserved, heterodimeric protein, that nucleates actin polymerization and binds to the barbed ends of actin filaments, preventing the addition or loss of actin monomers. CapZ interaction with actin filaments was shown to be of high affinity and decreased in the presence of PIP2. CapZ was located in nascent Z-lines during skeletal muscle myofibrillogenesis before the striated appearance of thin filaments in sarcomers. In this study, the stabilization and the anchorage of thin filaments were explored through identification of CapZ partners in the Z-line. Fish (sea bass) striated white muscle and its related Z-line proteins were selected since they correspond to the simplest Z-line organization. We report here the interaction between purified CapZ and alpha-actinin, a major component of Z filaments and polar links in Z-discs. Affinity of CapZ for alpha-actinin, estimated by fluorescence and immunochemical assays, is in the microM range. This association was found to be independent of actin and shown to be weakened in the presence of phosphoinositides. Binding contacts on the alpha-actinin molecule lie in the 55 kDa repetitive domain. A model including CapZ/alpha-actinin/titin/actin interactions is proposed considering Luther's 3D Z-line reconstruction.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinina/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Animais , Bass , Proteína de Capeamento de Actina CapZ , Células Cultivadas , Conectina , Substâncias Macromoleculares , Modelos Moleculares , Proteínas Quinases/metabolismo , Coelhos
13.
Leukemia ; 11(7): 1095-106, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9204997

RESUMO

Since there is no consensus on the techniques for multidrug resistance (MDR) phenotype evaluation, many discrepancies concerning the importance and frequency of mdr1 gene expression in leukemias and solid tumors are observed in the literature. In order to establish an inter-laboratory consensus in France, a multicenter study was carried out to propose further guidelines for MDR phenotype evaluation. The techniques used by the 38 laboratories participating in the trial were: immunodetection (immunohisto and/or cytochemistry, flow cytometry), functional tests, reverse transcription-polymerase chain reaction (RT-PCR) or Northern blot. We present the results obtained by 19 laboratories concerning the measurement of mdr1 gene expression assessed by RT-PCR or Northern blot in: (1)19 samples of tumor cells obtained from leukemic patients; (2) six solid tumor samples obtained at surgery; (3) eight cell lines exhibiting variable levels of resistance, and; (4)10 preparations of RNA and of cDNA obtained from solid tumors. Standardization of the RT-PCR technique and preliminary results comparing RT-PCR with immunohistochemistry in solid tumors are also reported.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Leucemia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Reação em Cadeia da Polimerase/normas , DNA Complementar/análise , Humanos , Imuno-Histoquímica , RNA/análise
14.
C R Seances Soc Biol Fil ; 190(4): 455-66, 1996.
Artigo em Francês | MEDLINE | ID: mdl-8952896

RESUMO

Drug resistance is a major obstacle to successful chemotherapy for cancer. When it occurs, resistance to a wide range of agents is noted. Factors that rule this resistance can be defined as pharmacologic and cellular. Pharmacologic factors are those that prevent an adequate degree of tumor cell exposure and include considerations of dose and schedule of drugs. Cellular factors are those that imply the tumor cell itself and it is probable that multiple mechanisms co-exists: 1) the drug transport across the tumor cell membrane and the duration of the drug exposure, 2) the drug metabolism (activation, inactivation), 3) the cellular targets and the DNA repair processes. The pleiotropic multidrug resistance (mdr, mrp, lrp), alterations of a target enzyme (topoisomerase II, protein kinase C, glutathione S transferase, O6 alkylguanine-DNA alkyltransferase) and the protein modifications (heat shock protein, metallothioneins) are the principal mechanisms involved. Several methods have been established for the determination of the presence of these drug resistance mechanisms but variations in the results are observed with the different methods used. Therefore, the value and the relative importance of these mechanisms in human tumor resistance is not yet established. In the mean-time, strategies to prevent and to overcome this resistance are developed.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Antineoplásicos/metabolismo , Genes MDR , Humanos , Neoplasias/enzimologia , Neoplasias/genética , Neoplasias/metabolismo
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