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1.
World Dev ; 135: 105064, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32834377

RESUMEN

Emerging evidence supports the intuitive link between chronic health conditions associated with air pollution and the vulnerability of individuals and communities to COVID-19. Poor air quality already imposes a highly significant public health burden in Northwest India, with pollution levels spiking to hazardous levels in November and early December when rice crop residues are burned. The urgency of curtailing the COVID-19 pandemic and mitigating a potential resurgence later in the year provides even more justification for accelerating efforts to dramatically reduce open agricultural burning in India.

2.
Artículo en Inglés | MEDLINE | ID: mdl-30961816

RESUMEN

Isolates of Pasteurella multocida recovered from infected humans (n = 15) were characterized by traditional and molecular microbiological methods and were compared with cat-derived strains (n = 5). The most prevalent subspecies among strains from human infections was P. multocida subsp. septica (80%), and nearly all isolates showed a similar combination of virulence-associated genes. MLST analysis classified the 20 P. multocida strains into 16 different sequence types, and we assigned 11 new sequence types (ST), however, only one of those (ST 334) was shared by two human and one cat isolates. P. multocida subsp. septica strains formed a distinct phylogenetic group within the species. The strains showed resistance to erythromycin, clindamycin and sulfamethoxazole, and with two exceptions, resistance to tilmicosin was also detected. Each strain was susceptible to ampicillin, streptomycin, gentamycin, tetracycline, doxycycline, cefazolin, cefpodoxime, chloramphenicol, florfenicol and enrofloxacin. Common characteristics (virulence profile and antibiotic sensitivity pattern) shared by strains isolated from humans and cats support the view that domestic cats may serve as a potential reservoir for P. multocida.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Pasteurella/microbiología , Infecciones por Pasteurella/veterinaria , Pasteurella multocida/genética , Pasteurella multocida/patogenicidad , Animales , Gatos , Clindamicina/farmacología , Eritromicina/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Pasteurella multocida/clasificación , Pasteurella multocida/aislamiento & purificación , Sulfametoxazol/farmacología , Tilosina/análogos & derivados , Tilosina/farmacología , Virulencia/genética
3.
Clin Microbiol Infect ; 25(11): 1429.e1-1429.e4, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30980925

RESUMEN

OBJECTIVES: In 2018, the European Committee on Antimicrobial Susceptibility Testing (EUCAST) introduced an intermediate breakpoint for ceftaroline against Staphylococcus aureus. The objective of this study was to compare data on resistance to ceftaroline among methicillin-resistant S. aureus (MRSA) isolates using versions 7.1 (March 2017) and 8.0 (January 2018) of the EUCAST breakpoints. METHODS: Participating centers were located in Africa, Asia, Europe, Oceania and South America. Isolates were collected from patients with complicated skin and soft-tissue infections and were cultured from integumentary sources. Methicillin resistance among S. aureus was confirmed locally using the oxacillin method. The CLSI broth microdilution method was used to measure ceftaroline MICs at the central laboratory. Versions 7.1 and 8.0 of the EUCAST breakpoints were used to interpret MIC data. RESULTS: Between 2015 and 2016, 9559 isolates of S. aureus were collected, of which 5566 (58.2%) isolates were MRSA. Overall, the lowest rate of MRSA was in Asia (56.5%; 705/1247) and the highest rate was in Oceania (62.7%; 299/477). Using version 7.1 of the EUCAST breakpoints, 4.5% (250/5566) of all MRSA isolates were resistant to ceftaroline and when version 8.0 of the breakpoints was applied, 4.2% (235/5566) of MRSA were in the intermediate category and 0.3% (15/5566) of all isolates were considered resistant. CONCLUSIONS: By applying version 8.0 of the EUCAST breakpoints, the majority of MRSA isolates that were resistant are now in the intermediate category for ceftaroline. Ceftaroline resistance among MRSA now appears rare.


Asunto(s)
Antibacterianos/farmacología , Cefalosporinas/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones de los Tejidos Blandos/microbiología , Infecciones Cutáneas Estafilocócicas/microbiología , Adolescente , Adulto , Femenino , Salud Global , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Adulto Joven , Ceftarolina
4.
Data Brief ; 18: 1484-1496, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29904651

RESUMEN

This data in brief article presents the data obtained during the validation of the optimized Biotyper Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) database. The validation was performed by the different expertise laboratories, collaborating within the European Network for the Rapid Identification of Anaerobes (ENRIA) project, using 6309 human clinical anaerobic bacterial strains. Different databases were compared with each other; the db 5989 database (V5 database); the V5 database complimented with Main Spectral Profiles (MSPs) of ENRIA strains added to the next update of the database; and the V5 database complimented with the MSPs of all anaerobic clinical isolates collected within the ENRIA project. For a comprehensive discussion of the full dataset, please see the research article that accompanies this data article (Veloo et al., 2018) [1].

5.
Anaerobe ; 54: 224-230, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29545163

RESUMEN

Within the ENRIA project, several 'expertise laboratories' collaborated in order to optimize the identification of clinical anaerobic isolates by using a widely available platform, the Biotyper Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Main Spectral Profiles (MSPs) of well characterized anaerobic strains were added to one of the latest updates of the Biotyper database db6903; (V6 database) for common use. MSPs of anaerobic strains nominated for addition to the Biotyper database are included in this validation. In this study, we validated the optimized database (db5989 [V5 database] + ENRIA MSPs) using 6309 anaerobic isolates. Using the V5 database 71.1% of the isolates could be identified with high confidence, 16.9% with low confidence and 12.0% could not be identified. Including the MSPs added to the V6 database and all MSPs created within the ENRIA project, the amount of strains identified with high confidence increased to 74.8% and 79.2%, respectively. Strains that could not be identified using MALDI-TOF MS decreased to 10.4% and 7.3%, respectively. The observed increase in high confidence identifications differed per genus. For Bilophila wadsworthia, Prevotella spp., gram-positive anaerobic cocci and other less commonly encountered species more strains were identified with higher confidence. A subset of the non-identified strains (42.1%) were identified using 16S rDNA gene sequencing. The obtained identities demonstrated that strains could not be identified either due to the generation of spectra of insufficient quality or due to the fact that no MSP of the encountered species was present in the database. Undoubtedly, the ENRIA project has successfully increased the number of anaerobic isolates that can be identified with high confidence. We therefore recommend further expansion of the database to include less frequently isolated species as this would also allow us to gain valuable insight into the clinical relevance of these less common anaerobic bacteria.


Asunto(s)
Bacterias Anaerobias/aislamiento & purificación , Infecciones Bacterianas/microbiología , Técnicas de Tipificación Bacteriana/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacterias Anaerobias/química , Bacterias Anaerobias/clasificación , Bacterias Anaerobias/genética , ADN Bacteriano/genética , Bases de Datos Factuales , Humanos , ARN Ribosómico 16S/genética
6.
Anaerobe ; 48: 94-97, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28797803

RESUMEN

Inter-laboratory reproducibility of Matrix Assisted Laser Desorption Time-of-Flight Mass Spectrometry (MALDI-TOF MS) of anaerobic bacteria has not been shown before. Therefore, ten anonymized anaerobic strains were sent to seven participating laboratories, an initiative of the European Network for the Rapid Identification of Anaerobes (ENRIA). On arrival the strains were cultured and identified using MALDI-TOF MS. The spectra derived were compared with two different Biotyper MALDI-TOF MS databases, the db5627 and the db6903. The results obtained using the db5627 shows a reasonable variation between the different laboratories. However, when a more optimized database is used, the variation is less pronounced. In this study we show that an optimized database not only results in a higher number of strains which can be identified using MALDI-TOF MS, but also corrects for differences in performance between laboratories.


Asunto(s)
Bacterias Anaerobias/clasificación , Técnicas de Tipificación Bacteriana/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacterias Anaerobias/genética , Bacterias Anaerobias/aislamiento & purificación , Humanos , ARN Ribosómico 16S/genética
7.
Clin Microbiol Infect ; 22(9): 793-798, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27404365

RESUMEN

Gram-positive anaerobic cocci (GPAC) account for 24%-31% of the anaerobic bacteria isolated from human clinical specimens. At present, GPAC are under-represented in the Biotyper MALDI-TOF MS database. Profiles of new species have yet to be added. We present the optimization of the matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) database for the identification of GPAC. Main spectral profiles (MSPs) were created for 108 clinical GPAC isolates. Identity was confirmed using 16S rRNA gene sequencing. Species identification was considered to be reliable if the sequence similarity with its closest relative was ≥98.7%. The optimized database was validated using 140 clinical isolates. The 16S rRNA sequencing identity was compared with the MALDI-TOF MS result. MSPs were added from 17 species that were not yet represented in the MALDI-TOF MS database or were under-represented (fewer than five MSPs). This resulted in an increase from 53.6% (75/140) to 82.1% (115/140) of GPAC isolates that could be identified at the species level using MALDI-TOF MS. An improved log score was obtained for 51.4% (72/140) of the strains. For strains with a sequence similarity <98.7% with their closest relative (n = 5) or with an inconclusive sequence identity (n = 4), no identification was obtained by MALDI-TOF MS or in the latter case an identity with one of its relatives. For some species the MSP of the type strain was not part of the confined cluster of the corresponding clinical isolates. Also, not all species formed a homogeneous cluster. It emphasizes the necessity of adding sufficient MSPs of human clinical isolates.


Asunto(s)
Bacterias Anaerobias/clasificación , Bacterias Grampositivas/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Bacterias Anaerobias/genética , Técnicas de Tipificación Bacteriana , Bases de Datos Factuales , Bacterias Grampositivas/genética , Humanos , Filogenia , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
8.
Lett Appl Microbiol ; 62(6): 437-43, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27100065

RESUMEN

UNLABELLED: This study aimed to screen the antibacterial activity of 160 extracts of 40 mushroom species, collected in Hungary, against 11 standard bacterial strains and 9 clinical isolates. The further objective of this work was to evaluate the capacity of active fungal extracts to potentiate the action of antibiotics against resistant pathogens. Disc-diffusion method was applied for screening of antibacterial activity of extracts. Microdilution method was used to determine minimum inhibitory concentrations. The active extracts were applied to different resistant micro-organisms (multiresistant Acinetobacter baumannii and Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecium and MRSA), combined with commercial drugs. The synergism between extracts and antibiotics was assessed by double-disc synergy assay and determination of fractional inhibitory concentration (FIC) with checkerboard technique. From 40 mushrooms included in this experiment, 16 species exhibited antibacterial effects with moderate to high potential. In general the chloroform extracts proved to be most active, while the aqueous and aqueous-methanolic extracts demonstrated low or no activity. Fistulina hepatica, Tapinella atrotomentosa (syn. Paxillus atrotomentosus) and Rhodocybe popinalis were the most active species; moreover, they can potentiate the action of cefuroxime against MRSA. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, 160 organic (n-hexane, chloroform and 50% methanol) and aqueous extracts of 40 mushroom species were submitted to antibacterial screening assay. The antibacterial capacity of 18 species has been examined for the first time. Nineteen extracts of 16 species showed antibacterial effects with moderate to high potential. The extracts of Fistulina hepatica, Tapinella atrotomentosa and Rhodocybe popinalis exhibited not only broad antibacterial spectrum, but also synergistic activity with cefuroxime against MRSA. Our screening study proved that mushroom species are promising sources of potential antimicrobial molecules. The results serve as good starting point for selection of fungal species for detailed pharmacological and chemical investigation.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Agaricales/química , Antibacterianos/farmacología , Extractos Celulares/farmacología , Enterococcus faecium/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Acinetobacter baumannii/crecimiento & desarrollo , Cefuroxima/farmacología , Farmacorresistencia Bacteriana Múltiple , Sinergismo Farmacológico , Enterococcus faecium/crecimiento & desarrollo , Humanos , Hungría , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana/métodos , Pseudomonas aeruginosa/crecimiento & desarrollo
9.
Mar Pollut Bull ; 77(1-2): 11-22, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24055460

RESUMEN

The oceans play a crucial role in the global environment and the sustainability of human populations, because of their involvement in climate regulation and provision of living and non-living resources to humans. Maintenance of healthy oceans in an era of increasing human pressure requires a high-level understanding of the processes occurring in the marine environment and the impacts of anthropogenic activities. Effective protection and sustainable resource management must be based, in part, on knowledge derived from successful research. Current marine research activities are being limited by a need for high-quality researchers capable of addressing critical issues in broad multidisciplinary research activities. This is particularly true for developing countries which will require the building of capacity for marine scientific research. This paper reviews the current activities aimed at increasing marine research capacity in developing and emerging countries and analyses the challenges faced, including: appropriate alignment of the research goals and societal and policy-relevant needs; training in multidisciplinary research; increasing capacity for overall synthesis of scientific data; building the capacity of technical staff; keeping highly qualified personnel in marine scientific research roles; cross-cultural issues in training; minimising duplication in training activities; improving linkages among human capital, project resources and infrastructure. Potential solutions to these challenges are provided, along with some priorities for action aimed at improving the overall research effort.


Asunto(s)
Participación de la Comunidad , Conservación de los Recursos Naturales/métodos , Países en Desarrollo , Ambiente , Humanos , Océanos y Mares , Investigación
10.
Artículo en Inglés | MEDLINE | ID: mdl-23533479

RESUMEN

Melampyrum pratense L. (Koch) is used in traditional Austrian medicine for the treatment of different inflammation-related conditions. In this work, we show that the extracts of M. pratense stimulated peroxisome proliferator-activated receptors- (PPARs-) α and - γ that are well recognized for their anti-inflammatory activities. Furthermore, the extract inhibited the activation of the proinflammatory transcription factor NF- κ B and induction of its target genes interleukin-8 (IL-8) and E-selectin in vitro. Bioassay-guided fractionation identified several active flavonoids and iridoids including melampyroside and mussaenoside and the phenolic compound lunularin that were identified in this species for the first time. The flavonoids apigenin and luteolin were distinguished as the main components accountable for the anti-inflammatory properties. Apigenin and luteolin effectively inhibited tumor necrosis factor α (TNF- α )-induced NF- κ B-mediated transactivation of a luciferase reporter gene. Furthermore, the two compounds dose-dependently reduced IL-8 and E-selectin protein expression after stimulation with lipopolysaccharide (LPS) or TNF- α in endothelial cells (ECs). The iridoids melampyroside and mussaenoside prevented the elevation of E-selectin in LPS-stimulated ECs. Lunularin was found to reduce the protein levels of the proinflammatory mediators E-selectin and IL-8 in ECs in response to LPS. These data validate the ethnomedical use of M. pratense for the treatment of inflammatory conditions and point to the constituents accountable for its anti-inflammatory activity.

11.
Eur J Microbiol Immunol (Bp) ; 2(2): 140-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24672683

RESUMEN

In spite of the developments in microbiological methods, blood cultures remain the cornerstone for the diagnosis of bacteraemia. Classically, minimum of two bottles are collected on a routine basis: an aerobic bottle, allowing preferential growth of aerobic and facultative anaerobic microorganisms, and an anaerobic bottle, providing suitable environment for strict anaerobic bacteria. Recent reports have documented a decrease in anaerobic bacteraemias and have questioned the need for routine anaerobic blood cultures. Bacteraemia due to anaerobic organisms occurs in 0.5-12% of blood cultures worldwide; however, recent studies from Europe and the USA presented inconsistent data regarding the prevalence of anaerobic bacteraemias between 1993 and 2006. The aims of this retrospective survey were to determine the prevalence of bacteraemias due to anaerobic bacteria and evaluate the importance of anaerobic blood cultures in a university hospital in Szeged, Hungary. We examined the occurrence of bacteraemias due to anaerobic bacteria during a 5-year period, from January 2005 to 2009, in order to identify current trends of anaerobic bacteraemias in our university.

12.
Ann Oncol ; 22(7): 1614-1621, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21245159

RESUMEN

BACKGROUND: Outcomes of Ewing tumor (ET) patients treated with allogeneic stem cell transplantation (allo-SCT) were compared regarding the use of reduced-intensity conditioning (RIC) and high-intensity conditioning (HIC) regimens as well as human leukocyte antigen (HLA)-matched and HLA-mismatched grafts. PATIENTS AND METHODS: We retrospectively analyzed data of 87 ET patients from the European Group for Blood and Marrow Transplantation, Pediatric Registry for Stem Cell Transplantations, Asia Pacific Blood and Marrow Transplantation and MetaEICESS registries treated with allo-SCT. Fifty patients received RIC (group A) and 37 patients received HIC (group B). Twenty-four patients received HLA-mismatched grafts and 63 received HLA-matched grafts. RESULTS: Median overall survival was 7.9 months [±1.24, 95% confidence interval (CI) 5.44-10.31] for group A and 4.4 months (±1.06, 95% CI 2.29-6.43) for group B patients (P = 1.3). Death of complications (DOC) occurred in 4 of 50 (0.08) and death of disease (DOD) in 33 of 50 (0.66) group A and in 16 of 37 (0.43) and 17 of 37 (0.46) group B patients, respectively. DOC incidence was decreased (P < 0.01) and DOD/relapse increased (P < 0.01) in group A compared with group B. HLA mismatch was not generally associated with graft-versus-Ewing tumor effect (GvETE). CONCLUSIONS: There was no improvement of survival with RIC compared with HIC due to increased DOD/relapse incidence after RIC despite less DOC incidence. This implicates general absence of a clinically relevant GvETE with current protocols.


Asunto(s)
Neoplasias Óseas/mortalidad , Neoplasias Óseas/terapia , Enfermedad Injerto contra Huésped/terapia , Sarcoma de Ewing/mortalidad , Sarcoma de Ewing/terapia , Trasplante de Células Madre , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Acondicionamiento Pretrasplante , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven
13.
Clin Microbiol Infect ; 17(3): 371-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20456453

RESUMEN

The susceptibilities of 824 Bacteroides fragilis group isolates against nine antibiotics were evaluated in a Europe-wide study involving 13 countries. Species determination, by different methods, was carried out on all but one isolate. Resistance rates were evaluated according to species and geographical areas via CLSI and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints. The present data were compared with those obtained 10 and 20 years ago at a European level. High-level resistance (MIC ≥ 64 mg/L) to ampicillin was observed in 44.5% of the strains, which is a significant increase relative to 20 years ago (16%). Piperacillin/tazobactam was more active than amoxicillin/clavulanic acid (3.1% and 10.4% resistance, respectively), again with a resistance increase relative to earlier studies. Dramatic increases in resistance were observed for cefoxitin, clindamycin and moxifloxacin, with rates of 17.2%, 32.4% and 13.6%, respectively. The lowest resistances were found for imipenem, metronidazole and tigecycline (1.2%, <1% and 1.7%). Nonsusceptible strains to imipenem and metronidazole were more resistant to other anti-anaerobic drugs. Differences were detected between geographical areas, with higher resistance rates for moxifloxacin in Scandinavian countries (21.4%) than in Mediterranean countries (5.4%), whereas, for clindamycin, the resistance rates were higher in Mediterranean (41.8%) and lower in Scandinavian countries (22.5%). Piperacillin/tazobactam resistance was also higher in Scandinavian countries.


Asunto(s)
Antibacterianos/farmacología , Infecciones por Bacteroides/microbiología , Bacteroides fragilis/efectos de los fármacos , Infecciones por Bacteroides/epidemiología , Bacteroides fragilis/aislamiento & purificación , Farmacorresistencia Bacteriana , Europa (Continente)/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Filogeografía
14.
Phys Rev Lett ; 104(1): 010503, 2010 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-20366355

RESUMEN

We present the first demonstration of a CNOT gate between two individually addressed neutral atoms. Our implementation of the CNOT uses Rydberg blockade interactions between neutral atoms held in optical traps separated by >8 microm. Using two different gate protocols we measure CNOT fidelities of F=0.73 and 0.72 based on truth table probabilities. The gate was used to generate Bell states with fidelity F=0.48+/-0.06. After correcting for atom loss we obtain an a posteriori entanglement fidelity of F=0.58.

16.
Clin Microbiol Infect ; 15(9): 885-6, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19702592

RESUMEN

A recent Supplement to Clinical Microbiology and Infection entitled 'Infection control measures to limit the spread of C. difficile' pointed out that the incidence of C. difficile-associated diarrhoea (CDAD) has been increasing worldwide, and stressed the importance of research in the fields of epidemiology and infection control [1]. Since 2003, one of the main causes of the increasing prevalence of CDAD has been claimed to be the emergence of PCR ribotype 027/NAP1, which has caused epidemics in North America, the UK, the Netherlands, Belgium and France. The presence of PCR ribotype 027 in Austria, Japan, Ireland, Germany and Switzerland has also been reported recently [2,3]. The majority of publications have emphasized that the presence of this strain is usually associated with more severe symptoms and signs than those associated with the other more common toxin-positive strains [4,5]. Whereas PCR ribotype 027 was present in the population earlier, the majority of the historic strains were fluoroquinolone sensitive [6]. The overuse of antibiotics such as fluoroquinolones may lead to the selection and emergence of resistant strains, and may contribute to the spread of PCR ribotype 027, which is usually resistant to erythromycin. Here, the Eastern European spread of C. difficile PCR ribotype 027 is reported.


Asunto(s)
Clostridioides difficile/clasificación , Clostridioides difficile/aislamiento & purificación , Diarrea/microbiología , Reacción en Cadena de la Polimerasa/métodos , Ribotipificación , Clostridioides difficile/genética , Humanos , Hungría , Masculino , Persona de Mediana Edad
17.
Clin Microbiol Infect ; 15(8): 796-802, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19438622

RESUMEN

Bacteroides fragilis and related species are important human pathogens involved in mixed infections of different origins. The B. fragilis group isolates are phenotypically very similar, grow more slowly than aerobic bacteria and, accordingly, are frequently misidentifed with classical or automated phenotypical identification methods. Recent taxonomic changes and new species accepted as members of the Bacteroides genus are not included in the different databases of commercially available identification kits. The use of matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was therefore evaluated for the species identification of 277 clinical isolates of the Bacteroides genus. Species identification was carried out with MALDI Bruker Daltonik Biotyper software (Bruker Daltonik GmbH, Bremen, Germany) by comparing the mass spectrum of each strain with the mass spectra of the 3260 reference strains currently available. The results of conventional phenotypical identification of the isolates were used as a reference. 16S rRNA gene sequencing was performed for a selection of the strains that gave discrepant results and for all those inconclusively identified by MALDI-TOF MS; 270 isolates (97.5%) were unequivocally identified [log(score) >/=2.0] by comparison with the reference strains present in the MALDI Biotyper database. Of the 23 isolates for which the MALDI-TOF MS species identification differed from the conventional phenotypical identification, 11 were sequenced. The sequencing data confirmed the MALDI-TOF MS result in ten cases and, for the remaining isolate, the sequencing data did not lead to the determination of the species, but only to that of the genus (Bacteroides sp.). The discriminating power and identification accuracy of MALDI-TOF MS proved to be superior to that of biochemical testing for Bacteroides thetaiotaomicron, Bacteroides ovatus and Bacteroides uniformis.


Asunto(s)
Técnicas Bacteriológicas/métodos , Infecciones por Bacteroides/microbiología , Bacteroides/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Técnicas de Tipificación Bacteriana , Bacteroides/química , Bacteroides/aislamiento & purificación , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Humanos , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad , Análisis de Secuencia de ADN
18.
J Dent Res ; 88(3): 280-4, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19329465

RESUMEN

There is growing evidence that chronic periodontitis may be a risk factor for pre-term birth. The goal of this intervention study was to determine the effect of periodontal treatment on the pregnancy outcome in women with threatening pre-term birth and initial localized chronic periodontitis. Forty-one women with a singleton pregnancy were enrolled in the study. For this treatment group, oral hygiene instruction and periodontal therapy were provided in the third trimester, while those in the control group (42 persons) did not receive any periodontal treatment. In the treatment group, the mean weight of newborns was 3079.0 g, compared with the control group mean of 2602.4 g. The incidence of pre-term birth and low birthweight in the treatment group was significantly less than in the control group (p = 0.015). Periodontal treatment completed before the 35th week appeared to have a beneficial effect on birth weight and time of delivery.


Asunto(s)
Periodontitis Crónica/terapia , Complicaciones del Embarazo/terapia , Nacimiento Prematuro/prevención & control , Adolescente , Adulto , Peso al Nacer , Profilaxis Dental , Raspado Dental , Escolaridad , Femenino , Edad Gestacional , Hemorragia Gingival/terapia , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Ocupaciones , Higiene Bucal , Educación del Paciente como Asunto , Bolsa Periodontal/terapia , Embarazo , Resultado del Embarazo , Tercer Trimestre del Embarazo , Características de la Residencia , Clase Social , Adulto Joven
19.
J Microsc ; 231(3): 506-17, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18755006

RESUMEN

Filopodia are rod-shaped cell surface protrusions composed of a parallel bundle of actin filaments. Since filopodia frequently emanate from lamellipodia, it has been proposed that they form exclusively by the convergence and elongation of actin filaments generated in lamellipodia networks. However, filopodia form without Arp2/3-complex, which is essential for lamellipodia formation, indicating that actin filaments in filopodia may be generated by other nucleators. Here we analyzed the effects of ectopic expression of GFP-tagged full length or a constitutively active variant of the human formin mDia2/Drf3. By contrast to the full-length molecule, which did not affect cell behaviour and was entirely cytosolic, active Drf3 lacking the C-terminal regulatory region (Drf3DeltaDAD) induced the formation of filopodia and accumulated at their tips. Low expression of Drf3DeltaDAD induced rod-shaped or tapered filopodia, whereas over-expression resulted in multiple, club-shaped filopodia. The clubs were filled with densely bundled actin filaments, whose number but not packing density decreased further away from the tip. Interestingly, clubs frequently increased in width after protrusion beyond the cell periphery, which correlated with increased amounts of Drf3DeltaDAD at their tips. These data suggest Drf3-induced filopodia form and extend by de novo nucleation of actin filaments instead of convergent elongation. Finally, Drf3DeltaDAD also induced the formation of unusual, lamellipodia-like structures, which contained both lamellipodial markers and the prominent filopodial protein fascin. Microarray analyses revealed highly variable Drf3 expression levels in different commonly used cell lines, reflecting the need for more detailed analyses of the functions of distinct formins in actin cytoskeleton turnover and different cell types.


Asunto(s)
Proteínas Portadoras/metabolismo , Seudópodos/ultraestructura , Citoesqueleto de Actina/metabolismo , Animales , Fusión Artificial Génica , Proteínas Portadoras/genética , Línea Celular , Células Cultivadas , Forminas , Perfilación de la Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Ratones , Proteínas de Microfilamentos/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Seudópodos/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia
20.
Phys Rev Lett ; 100(11): 113003, 2008 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-18517782

RESUMEN

We demonstrate Rabi oscillations of small numbers of 87Rb atoms between ground and Rydberg states with n< or =43. Coherent population oscillations are observed for single atoms, while the presence of two or more atoms decoheres the oscillations. We show that these observations are consistent with van der Waals interactions of Rydberg atoms.

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