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1.
Euro Surveill ; 24(35)2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31481147

RESUMEN

BackgroundClostridioides difficile is a leading cause of healthcare-associated diarrhoea in middle and high-income countries. Up to 2018, there has been no systematic, annual surveillance for C. difficile infections (CDI) in France.AimsTo provide an updated overview of the epidemiology of CDI in France between 2010 and 2017 based on five different data sources.MethodsThis is a descriptive study of retrospective surveillance and alerts data. Incidence of CDI cases was estimated through the CDI incidence survey (2016) and data from the French National Uniform Hospital Discharge Database (PMSI; 2010-16). Testing frequency for CDI was estimated through the CDI incidence survey and point prevalence studies on healthcare-associated infections (HAI; 2012 and 2017). The national early warning response system for HAI (HAI-EWRS, 2012-17) and National Reference Laboratory data (2012-17) were used to follow the number of severe CDI cases and/or outbreaks.ResultsIn 2016, CDI incidence in acute care was 3.6 cases per 10,000 patient days (PD). There was a statistically significant increase in CDI incidence between 2010 and 2016 (+ 14% annually) and testing frequency was 47.4 per 10,000 PD. The number of CDI HAI-EWRS notifications decreased between 2015 and 2017 with only a few large outbreaks reported.ConclusionThe CDI incidence estimate increased from 2010, but remained below the European average of 7 per 10,000 PD in 2014; there were fewer severe cases or clusters reported in France. The consistency between PMSI and laboratory-based estimated CDI incidence could allow for more routine monitoring of CDI incidence.


Asunto(s)
Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/epidemiología , Infección Hospitalaria/epidemiología , Diarrea/microbiología , Pacientes Internos/estadística & datos numéricos , Vigilancia de la Población/métodos , Clostridioides difficile/genética , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/microbiología , Estudios Transversales , Diarrea/epidemiología , Brotes de Enfermedades , Francia/epidemiología , Hospitales , Humanos , Incidencia , Tiempo de Internación , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Retrospectivos , Ribotipificación
2.
Euro Surveill ; 20(36)2015.
Artículo en Inglés | MEDLINE | ID: mdl-26536042

RESUMEN

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are a major focus of multidrug-resistant organisms (MRO) surveillance programmes in France. To describe the temporal and geographical trends of these pathogens, we conducted an epidemiological study based on data extracted from the nationwide MRO surveillance network from 2009 to 2013. During this time, the incidence of ESBL-E infections in French hospitals increased by 73%, from 0.35 to 0.60 per 1,000 patient days (PD) (p<0.001) and ESBL-E bacteraemia by 77%, from 0.03 to 0.05 per 1,000 PD (p<0.001). The incidence of ESBL-E infections was higher in intensive-care units (1.62 to 2.44 per 1,000 PD (p<0.001)) than in recovery and long-term care facilities (0.20 to 0.31 per 1,000 PD (p<0.001)). Escherichia coli was the most frequent extended-spectrum beta-lactamase-producing (ESBL) pathogen, representing 59% (26,238/44,425) of all ESBL isolates, followed by Klebsiella pneumoniae (20%; 8,856/44,425) in 2013. The most frequent infection was urinary tract infection, for all species. The incidence of ESBL-E varied by region but showed an upward trend overall. Reinforcement of control measures for halting the spread of such MRO is crucial.


Asunto(s)
Brotes de Enfermedades , Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/aislamiento & purificación , Infecciones Urinarias/microbiología , Resistencia betalactámica , beta-Lactamasas/metabolismo , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae/enzimología , Enterobacteriaceae/genética , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/microbiología , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/epidemiología , Francia/epidemiología , Humanos , Incidencia , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Vigilancia de la Población , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/epidemiología , Resistencia betalactámica/genética , beta-Lactamasas/genética
3.
Infect Control Hosp Epidemiol ; 45(1): 27-34, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37529839

RESUMEN

OBJECTIVE: To evaluate the performance of a comorbidity-based risk-adjustment model for surgical-site infection (SSI) reporting and benchmarking using a panel of variables extracted from the hospital discharge database (HDD), including comorbidities, compared to other models that use variables from different data sources. METHODS: The French national surveillance program for SSI (SPICMI) has collected data from voluntary hospitals in the first 6 months of 2020 and 2021, for 16 selected surgery procedures, using a semiautomated algorithm for detection. Four risk-adjustment models were selected with logistic regression analysis, combining the different patterns of variables: National Nosocomial Infections Surveillance System (NNIS) risk-index components, individual operative data, and 6 individual comorbidities according to International Classification of Disease, Tenth Revision (ICD-10) diagnosis: obesity, diabetes, malnutrition, hypertension, cancer, or immunosuppression. Areas under the curve (AUCs) were calculated and compared. RESULTS: Overall, 294 SSI were detected among 11,975 procedures included. All 6 comorbidities were related to SSI in the univariate analysis. The AUC of the selected model including comorbidities (0.675; 95% confidence interval [CI], 0.642-0.707), was significantly higher than the AUC of the model without comorbidities (0.641; 95% CI, 0.609-0.672; P = .016) or the AUC using the NNIS-index components (0.598; 95% CI, 0.564-0.630; P < .001). The HDD-based model AUC (0.659; 95% CI, 0.625-0.692) did not differ significantly from the selected model without comorbidities (P = .23). CONCLUSION: Including HDD-based comorbidities as patient case-mix variables instead of NNIS risk index factors could be an effective approach for risk-adjustment of automated SSI surveillance more widely accessible to hospitals.


Asunto(s)
Infección Hospitalaria , Vigilancia de la Población , Humanos , Vigilancia de la Población/métodos , Infección de la Herida Quirúrgica/epidemiología , Hospitales , Infección Hospitalaria/epidemiología , Factores de Riesgo , Comorbilidad , Francia/epidemiología
4.
J Antimicrob Chemother ; 68(4): 954-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23194721

RESUMEN

BACKGROUND: In the mid-1990s, the prevalence rate of multidrug-resistant bacteria (MDRB) in French hospitals was high and control of MDRB spread then became a major priority in the national infection control programme (ICP). METHODS: To evaluate the impact of the ICP, a national coordination of MDRB surveillance was set up in 2002. Data were collected 3 months a year in healthcare facilities (HCFs) on a voluntary basis. All clinical specimens of methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBLE) were prospectively included. Incidences per 1000 patient days (PDs) were calculated and trends in incidence from 2003 to 2010 were assessed. RESULTS: Participation in the surveillance increased from 478 HCFs in 2002 to 933 in 2010. In 2010, MRSA incidence was 0.40/1000 PDs: 1.14 in intensive care units (ICUs), 0.48 in acute care facilities (ACFs) and 0.27 in rehabilitation and long-term care facilities (RLTCFs). ESBLE incidence was 0.39/1000 PDs: 1.63 in ICUs, 0.46 in ACFs and 0.23 in RLTCFs. MRSA incidence significantly decreased from 0.72/1000 PDs in 2003 to 0.41/1000 PDs in 2010 (P<10(-3)); in contrast, ESBLE incidence significantly increased from 0.17/1000 PDs to 0.48/1000 PDs (P<10(-3)). The most prevalent ESBLE were Enterobacter aerogenes (34%) and Escherichia coli (25%) in 2003 and E. coli (60%) and Klebsiella pneumoniae (18%) in 2010. CONCLUSION: These results demonstrate the positive impact of the national ICP on MRSA rates. In contrast, ESBLE incidence, especially ESBL-producing E. coli, is increasing dramatically and represents a serious threat for hospitals and for the community that deserves specific control actions.


Asunto(s)
Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Francia , Hospitales , Humanos , Incidencia , Control de Infecciones/métodos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , beta-Lactamasas/metabolismo
5.
Nucleic Acids Res ; 39(8): 3458-72, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21149268

RESUMEN

Nucleoside Monophosphate Kinases (NMPKs) family are key enzymes in nucleotide metabolism. Bacterial UMPKs depart from the main superfamily of NMPKs. Having no eukaryotic counterparts they represent attractive therapeutic targets. They are regulated by GTP and UTP, while showing different mechanisms in Gram(+), Gram(-) and archaeal bacteria. In this work, we have characterized the mycobacterial UMPK (UMPKmt) combining enzymatic and structural investigations with site-directed mutagenesis. UMPKmt exhibits cooperativity toward ATP and an allosteric regulation by GTP and UTP. The crystal structure of the complex of UMPKmt with GTP solved at 2.5 Å, was merely identical to the modelled apo-form, in agreement with SAXS experiments. Only a small stretch of residues was affected upon nucleotide binding, pointing out the role of macromolecular dynamics rather than major structural changes in the allosteric regulation of bacterial UMPKs. We further probe allosteric regulation by site-directed mutagenesis. In particular, a key residue involved in the allosteric regulation of this enzyme was identified.


Asunto(s)
Proteínas Bacterianas/química , Mycobacterium tuberculosis/enzimología , Nucleósido-Fosfato Quinasa/química , Regulación Alostérica , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cristalografía por Rayos X , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Nucleósido-Fosfato Quinasa/genética , Nucleósido-Fosfato Quinasa/metabolismo , Homología de Secuencia de Aminoácido
6.
Prehosp Disaster Med ; 38(4): 522-528, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37317865

RESUMEN

Following the two earthquakes that occurred in Turkey on February 6, 2023 with magnitudes of 7.8 and 7.5, causing over 50,000 deaths and 100,000 injuries, France proposed to deploy, via the European Union Civil Protection Mechanism (EUCPM), the French Civil Protection Field Hospital (ESCRIM [Élément de Sécurité Civile Rapide d'Intervention Médicale]): the French World Health Organization (WHO)-classified Emergency Medical Team (EMT) Level 2 (EMT2).After the acceptance from Turkey on February 8, a disaster assessment team (DAT) was sent on February 10, 2023. It was decided, with local health authorities (LHA), to set up the field hospital in Gölbasi, Adiyaman Province where the State Hospital was closed due to a structural risk.Arriving in Gölbasi on February 13 at 2:00am in -12°C (10°F) temperatures, the detachment had no choice but to begin setting up the base of operation (BoO). At dawn, the cold was so intense that one doctor suffered from frostbite. Once the BoO was installed, the team set up the hospital tents. From 11:00am, the sun melted the snow and the ground became very muddy. The objective being to open the hospital as soon as possible, installation of the hospital continued, and it opened on February 14 at 12:00pm/noon, less than 36 hours after on-site arrival.This article describes the mechanics of setting up an EMT-2 in a cold climate, the many problems encountered, and the solutions imagined and proposed.


Asunto(s)
Planificación en Desastres , Desastres , Terremotos , Humanos , Unidades Móviles de Salud , Turquía
7.
Front Microbiol ; 11: 1161, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582101

RESUMEN

Facing the emergence of difficult-to-treat bacterial infections, the perspective of using bacteriophages has re-gained interest in many countries. In terms of pharmaceutical classification in EU and United States, phages are considered as anti-infectious medicinal products and biological products, given the intended use and their live nature. During the production steps, the compliance with the Good Manufacturing Practice (GMP) represents the gold-standard to ensure the quality, safety and efficacy of medicinal products, either investigational or approved. In practice, the implementation of GMP rules for phage therapy medicinal products benefits from the long history of vaccine development. Accordingly, a well-structured strategy can be defined for each medicinal product, taking into account the specified indication (i.e., the target bacteria species, the infected site, the route of administration, the product composition). Based on the experience of different phage therapy medicinal products from the recent years, the most important requirements to achieve and claim GMP grade are reviewed here, including for genetically modified phages. Like all new medicinal products, the manufacturing of investigational phages incorporates significant challenges. However, the use of GMP-certified phages provides the best guarantee for the rigorous assessment of quality, safety and efficacy during the clinical development of phage medicinal products, thus appears as a key component for the successful development of phage therapy approaches.

8.
J Clin Microbiol ; 47(6): 1961-4, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19386853

RESUMEN

We describe an outbreak of severe subcutaneous infections due to nontuberculous mycobacteria following mesotherapy. Epidemiological studies and molecular comparisons of Mycobacterium chelonae strains from different patients and the environment suggested that contamination may be associated with inappropriate cleaning of the multiple-injection device with tap water.


Asunto(s)
Brotes de Enfermedades , Inyecciones/efectos adversos , Infecciones por Mycobacterium/diagnóstico , Infecciones por Mycobacterium/epidemiología , Mycobacterium chelonae/aislamiento & purificación , Enfermedades Cutáneas Bacterianas/diagnóstico , Enfermedades Cutáneas Bacterianas/epidemiología , Adulto , Técnicas de Tipificación Bacteriana , Análisis por Conglomerados , Dermatoglifia del ADN , Electroforesis en Gel de Campo Pulsado , Microbiología Ambiental , Femenino , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Infecciones por Mycobacterium/microbiología , Mycobacterium chelonae/clasificación , Mycobacterium chelonae/genética , Enfermedades Cutáneas Bacterianas/microbiología , Adulto Joven
9.
Lancet Infect Dis ; 19(1): 35-45, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30292481

RESUMEN

BACKGROUND: Wound infections are the main cause of sepsis in patients with burns and increase burn-related morbidity and mortality. Bacteriophages, natural bacterial viruses, are being considered as an alternative therapy to treat infections caused by multidrug-resistant bacteria. We aimed to compare the efficacy and tolerability of a cocktail of lytic anti-Pseudomonas aeruginosa bacteriophages with standard of care for patients with burns. METHODS: In this randomised phase 1/2 trial, patients with a confirmed burn wound infection were recruited from nine burn centres in hospitals in France and Belgium. Patients were eligible if they were aged 18 years or older and had a burn wound clinically infected with P aeruginosa. Eligible participants were randomly assigned (1:1) by use of an interactive web response system to a cocktail of 12 natural lytic anti-P aeruginosa bacteriophages (PP1131; 1 × 106 plaque-forming units [PFU] per mL) or standard of care (1% sulfadiazine silver emulsion cream), both given as a daily topical treatment for 7 days, with 14 days of follow-up. Masking of treatment from clinicians was not possible because of the appearance of the two treatments (standard of care a thick cream, PP1131 a clear liquid applied via a dressing), but assignments were masked from microbiologists who analysed the samples and patients (treatment applied while patients were under general anaesthetic). The primary endpoint was median time to sustained reduction in bacterial burden by at least two quadrants via a four-quadrant method, assessed by use of daily swabs in all participants with a microbiologically documented infection at day 0 who were given at least one sulfadiazine silver or phage dressing (modified intention-to-treat population). Safety was assessed in all participants who received at least one dressing according to protocol. Ancillary studies were done in the per-protocol population (all PP1131 participants who completed 7 days of treatment) to assess the reasons for success or failure of phage therapy. This trial is registered with the European Clinical Trials database, number 2014-000714-65, and ClinicalTrials.gov, number NCT02116010, and is now closed. FINDINGS: Between July 22, 2015, and Jan 2, 2017, across two recruitment periods spanning 13 months, 27 patients were recruited and randomly assigned to receive phage therapy (n=13) or standard of care (n=14). One patient in the standard of care group was not exposed to treatment, giving a safety population of 26 patients (PP1131 n=13, standard of care n=13), and one patient in the PP1131 group did not have an infection at day 0, giving an efficacy population of 25 patients (PP1131 n=12, standard of care n=13). The trial was stopped on Jan 2, 2017, because of the insufficient efficacy of PP1131. The primary endpoint was reached in a median of 144 h (95% CI 48-not reached) in the PP1131 group versus a median of 47 h (23-122) in the standard of care group (hazard ratio 0·29, 95% CI 0·10-0·79; p=0·018). In the PP1131 group, six (50%) of 12 analysable participants had a maximal bacterial burden versus two (15%) of 13 in the standard of care group. PP1131 titre decreased after manufacturing and participants were given a lower concentration of phages than expected (1 × 102 PFU/mL per daily dose). In the PP1131 group, three (23%) of 13 analysable participants had adverse events versus seven (54%) of 13 in the standard of care group. One participant in each group died after follow-up and the deaths were determined to not be related to treatment. The ancillary study showed that the bacteria isolated from patients with failed PP1131 treatment were resistant to low phage doses. INTERPRETATION: At very low concentrations, PP1131 decreased bacterial burden in burn wounds at a slower pace than standard of care. Further studies using increased phage concentrations and phagograms in a larger sample of participants are warranted. FUNDING: European Commission: Framework Programme 7.


Asunto(s)
Quemaduras/microbiología , Quemaduras/terapia , Tolerancia a Medicamentos , Terapia de Fagos/métodos , Infecciones por Pseudomonas/terapia , Fagos Pseudomonas , Adulto , Anciano , Antibacterianos/uso terapéutico , Bélgica , Método Doble Ciego , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/virología , Resultado del Tratamiento
10.
J Antimicrob Chemother ; 62(4): 823-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18658196

RESUMEN

BACKGROUND: In France, antibiotic consumption (ABC) is dramatically high in parallel with the high rate of multidrug-resistant bacteria. For the last few years, a nationwide policy has been implemented at the national level to control and monitor ABC. Since 2002, surveillance networks have been set up with voluntary hospitals to evaluate the antibiotic policy and consumption. The present study was conducted to identify whether specific control measures of the antibiotic policy could reduce ABC in hospitals. METHODS: Based on the data from the Northern France surveillance system, local recommendations and antibiotic use were collected annually on a standardized questionnaire that had 21 items. ABC was expressed in defined daily doses (DDDs) per 1000 patient-days (PDs). The ABC indicator was the overall antibiotic consumption. A multivariate logistic regression analysis was performed using low (< or =75th percentile) and high (>75th percentile) ABC as the dependent variable. RESULTS: A total of 83/111 hospitals were included in the study. In 75% of the hospitals, total ABC was < or =669.5 DDDs/1000 PDs. The less frequent practices were educational antibiotic programmes (17%), authorization from an antibiotic specialist for selected antibiotics (26%) and systematic reassessment of AB treatment after 72 h (27%). In the multivariate analysis, three variables remained significantly and independently associated (P < 0.05) with ABC: the type of hospital, the proportion of non-acute-care beds and the nominative delivery form as the only antibiotic control measure. Total ABC was lower in hospitals having a nominative delivery form, compared with hospitals not having it. Conversely, ABC was significantly higher in public teaching hospitals compared with non-teaching hospitals. Similarly, ABC was higher in hospitals with a lowest proportion (i.e. < or =25%) of non-acute-care beds compared with hospitals where this proportion was >25%. CONCLUSIONS: Specific control measures could lower ABC. Sustained control efforts should focus on antibiotics with the highest potential for emerging bacterial resistance.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana , Utilización de Medicamentos/tendencias , Política de Salud , Utilización de Medicamentos/estadística & datos numéricos , Francia , Adhesión a Directriz , Hospitales , Humanos , Modelos Logísticos , Análisis Multivariante , Proyectos Piloto , Encuestas y Cuestionarios
11.
Chem Commun (Camb) ; (6): 787-8, 2005 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-15685338

RESUMEN

Isoelectric focusing in a polyacrylamide pH gradient gel is used to analyze the size distribution of gold nanoparticles synthesized by a chemical route with mercaptosuccinic acid as a ligand. The isoelectric point of the nanoparticles is shown to be size dependent, allowing fractionation by electrophoresis. Each fraction has a narrow size distribution with a standard deviation lower than 0.4 nm.

12.
Structure ; 21(6): 975-85, 2013 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-23643948

RESUMEN

Inosine-5'-monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme in nucleotide biosynthesis studied as an important therapeutic target and its complex functioning in vivo is still puzzling and debated. Here, we highlight the structural basis for the regulation of IMPDHs by MgATP. Our results demonstrate the essential role of the CBS tandem, conserved among almost all IMPDHs. We found that Pseudomonas aeruginosa IMPDH is an octameric enzyme allosterically regulated by MgATP and showed that this octameric organization is widely conserved in the crystal structures of other IMPDHs. We also demonstrated that human IMPDH1 adopts two types of complementary octamers that can pile up into isolated fibers in the presence of MgATP. The aggregation of such fibers in the autosomal dominant mutant, D226N, could explain the onset of the retinopathy adRP10. Thus, the regulatory CBS modules in IMPDHs are functional and they can either modulate catalysis or macromolecular assembly.


Asunto(s)
Adenosina Trifosfato/metabolismo , IMP Deshidrogenasa/metabolismo , Regulación Alostérica , Sitios de Unión , Biopolímeros/metabolismo , Cristalografía por Rayos X , Microscopía Electrónica , Modelos Moleculares , Conformación Proteica , Pseudomonas aeruginosa/enzimología , Proteínas Recombinantes/metabolismo
13.
J Inorg Biochem ; 106(1): 164-71, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22119809

RESUMEN

Genome sequencing has shown the presence of genes coding for NO-synthase (NOS)-like proteins in bacteria. The roles and properties of these proteins remain unclear. UV-visible spectroscopy was used to characterize the recombinant NOS-like protein from Bacillus subtilis (bsNOS) in its ferric and ferrous states in the presence of various Fe(III)- and Fe(II)-heme-ligands and of a series of L-arginine (L-arg) analogs. BsNOS exhibited several spectroscopic and binding properties in common with Bacillus anthracis NOS (baNOS) that were clearly different from those of tetrahydrobiopterin (H4B)-free mammalian NOS oxygenase domains (mNOS(oxys)) and of Staphylococcus aureus NOS (saNOS). Interestingly, bsNOS and baNOS that do not contain H4B exhibited properties much closer to those of H4B-containing mNOS(oxys). Moreover, bsNOS was found to efficiently catalyze the oxidation of L-arginine into L-citrulline by H(2)O(2), whereas H4B-free mNOS(oxys) exhibited low activities for this reaction.


Asunto(s)
Arginina/metabolismo , Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , Óxido Nítrico Sintasa/metabolismo , Animales , Arginina/química , Bacterias/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Sitios de Unión/genética , Biocatálisis , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Citrulina/química , Citrulina/metabolismo , Compuestos Férricos/química , Compuestos Férricos/metabolismo , Compuestos Ferrosos/química , Compuestos Ferrosos/metabolismo , Hemo/química , Hemo/metabolismo , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Imidazoles/metabolismo , Cinética , Mamíferos/metabolismo , Óxido Nítrico Sintasa/química , Óxido Nítrico Sintasa/genética , Oxidación-Reducción , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especificidad de la Especie , Espectrofotometría
14.
Electrophoresis ; 26(9): 1650-8, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15815996

RESUMEN

The Off-Gel technology was recently described for protein fractionation in a solution placed on top of an immobilized pH gradient gel. In addition, this process was found to remove salts from the biological samples to analyze. This desalting effect is studied experimentally in a conductometric prototype cell. A simplified analytical model is developed to understand this process and a good agreement is found with the conductivity measurements. To illustrate the desalting of a biological sample, a 1 mg.mL(-1) solution of beta-lactoglobulin A in 0.1 M NaCl is subjected to electrophoresis in a single compartment Off-Gel cell. The analysis of the resulting sample by ESI-MS demonstrates the effective removal of salt. A finite element diffusion-migration model is also used to illustrate how the nonuniformity of the electric field in the cell, associated with the salt migration, can slow down the desalting process.


Asunto(s)
Electroforesis/métodos , Proteínas/aislamiento & purificación , Cloruro de Sodio/química , Conductividad Eléctrica , Lactoglobulinas/química , Lactoglobulinas/aislamiento & purificación , Proteínas/química
15.
Ann Thorac Surg ; 80(2): 423-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16039177

RESUMEN

BACKGROUND: Neoadjuvant chemotherapy before resection of nonsmall cell lung cancer seems to increase survival, mainly in the early stage. Risks of postoperative complications after chemotherapy and surgery remain controversial. Here we review our experience with patients treated in one thoracic surgery center. METHODS: Patients undergoing resection for nonsmall cell lung cancer after induction chemotherapy between January 1993 and March 2002 were reviewed. Data collected included age, sex, preoperative forced expiratory volume in 1 second (FEV1), hemoglobin, and arterial oxygen pressure tension (PaO2), postoperative complications, and global survival. The main objectives were postoperative mortality and morbidity. Postoperative mortality and morbidity were defined as complications or deaths occurring within 30 days after surgery. Predictive morbidity factors were identified by univariate and multivariate analysis and overall survival by the Kaplan-Meier method. RESULTS: In all, 114 patients were reviewed. Different induction chemotherapies were used, mainly cisplatin with vinorelbine or gemicitabine. Postoperative mortality was 2 of 114, 1 of 27 after pneumonectomy, and there were no deaths after lobectomy. Complications occurred in 29% of patients (33 of 114), usually infectious pneumonia and anemia requiring transfusion. Preoperative FEV1, hemoglobin, and PaO2 are not associated with morbidity in univariate or multivariate analysis. CONCLUSIONS: Preoperative chemotherapy does not increase postoperative mortality and morbidity after nonsmall cell lung cancer surgery, performed exclusively by thoracic surgeons.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Terapia Neoadyuvante , Neumonectomía , Adulto , Anciano , Carboplatino/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Cisplatino/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Escisión del Ganglio Linfático , Masculino , Mediastino , Persona de Mediana Edad , Complicaciones Posoperatorias , Radioterapia Adyuvante , Análisis de Supervivencia , Toracotomía , Vinblastina/administración & dosificación , Vinblastina/análogos & derivados , Vinorelbina , Gemcitabina
16.
Electrophoresis ; 23(19): 3253-61, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12373750

RESUMEN

The protonation of an aqueous solution of two ampholytes AH and BH next to a gel buffered by immobilized acid moieties IH has been studied by finite element simulation in an iterative scheme. A ten species model has been formulated, taking into account transient diffusion and equilibrium kinetics of the two amphoteric species AH and BH, of water and of the immobilized species IH. This model has been developed to illustrate the pH evolution between an ampholyte solution and an Immobiline gel, and to study the influence of the Immobiline concentration on protons and ampholyte distributions. It has been demonstrated that a minimum initial Immobiline concentration of 10(-2) M is necessary to maintain the pH in the gel in contact with a closed chamber, when the difference between the isoelectric points of AH and BH is 4 and when the initial concentration of the ampholytes in solution is in the micromolar range. This approach provides a first theoretical framework for the recently developed Off-Gel trade mark electrophoresis.


Asunto(s)
Tampones (Química) , Electroforesis/métodos , Modelos Químicos , Difusión , Geles , Concentración de Iones de Hidrógeno , Cinética , Reproducibilidad de los Resultados , Soluciones/química
17.
Electrophoresis ; 24(1-2): 3-11, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12652567

RESUMEN

A new protein fractionation technique based on off-gel isoelectric focusing (IEF) is presented, where the proteins are separated according to their isoelectric point (pI) in a multiwell device with the advantage to be directly recovered in solution for further analysis. The protein fractions obtained with this technique have then been characterized with polymer nanoelectrospray for mass spectrometry (MS) analyses or with Bioanalyzer for mass identification. This methodology shows the possibility of developing alternatives to the classical two-dimensional (2-D) gel electrophoresis. One species numerical simulation of the electric field distribution during off-gel separation is also presented in order to demonstrate the principle of the purification. Experiments with pI protein markers have been carried out in order to highlight the kinetics and the efficiency of the technique. Moreover, the resolution of the fractionation was shown to be 0.1 pH unit for the separation of beta-lactoglobulin A and B. In addition, the isoelectric fractionation of an Escherichia coli extract was performed in standard solubilization buffer to demonstrate the performances of the technique, notably for proteomics applications.


Asunto(s)
Focalización Isoeléctrica/instrumentación , Proteínas/aislamiento & purificación , Animales , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/aislamiento & purificación , Humanos , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica/métodos , Punto Isoeléctrico , Lactoglobulinas/química , Lactoglobulinas/aislamiento & purificación , Proteínas/química , Espectrometría de Masa por Ionización de Electrospray
18.
Electrophoresis ; 24(21): 3533-62, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14613180

RESUMEN

We present the state-of-the-art in miniaturized sample preparation, immunoassays, one-dimensional and multidimensional analyte separations, and coupling of microdevices with electrospray ionization-mass spectrometry. Hyphenation of these different techniques and their relevance to proteomics will be discussed. In particular, we will show that analytical performances of microfluidic analytical systems are already close to fulfill the requirements for proteomics, and that miniaturization results at the same time in a dramatic increase in analysis throughput. Throughout this review, some examples of analytical operations that cannot be achieved without microfluidics will be emphasized. Finally, conditions for the spreading of microanalytical systems in routine proteomic labs will be discussed.


Asunto(s)
Microfluídica/métodos , Proteoma , Electroforesis/métodos , Enzimas/análisis , Enzimas/metabolismo , Miniaturización/métodos
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