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1.
Mol Cell ; 32(1): 129-39, 2008 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-18851839

RESUMEN

Transcription of the lysozyme gene is rapidly induced by proinflammatory stimuli such as treatment with bacterial lipopolysaccharide (LPS). Here we show that this induction involves both the relief of repression mediated by the enhancer-blocking protein CTCF that binds to a negative regulatory element at -2.4 kb, and the activation of two flanking enhancer elements. The downstream enhancer has promoter activity, and LPS stimulation initiates the transient synthesis of a noncoding RNA (LINoCR) transcribed through the -2.4 kb element. Expression of LINoCR is correlated with IKKalpha recruitment, histone H3 phosphoacetylation in the transcribed region, the repositioning of a nucleosome over the CTCF binding site, and, eventually, CTCF eviction. Each of these events requires transcription elongation. Our data reveal a transcription-dependent mechanism of chromatin remodeling that switches a cis-regulatory region from a repressive to an active conformation.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Muramidasa/genética , Proteínas Represoras/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Factor de Unión a CCCTC , Línea Celular , Pollos , Cartilla de ADN/genética , Elementos de Facilitación Genéticos , Histonas/metabolismo , Lipopolisacáridos/farmacología , Nucleosomas/efectos de los fármacos , Nucleosomas/metabolismo , Fosforilación , Regiones Promotoras Genéticas , Interferencia de ARN , ARN Polimerasa II/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN no Traducido/genética , Elementos Reguladores de la Transcripción , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
2.
Blood ; 119(8): 1831-7; quiz 1956, 2012 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-22010103

RESUMEN

The identification of the causative organism in invasive pulmonary aspergillosis (IPA) is recommended. We investigated whether a mycologic diagnostic strategy could be optimized based on patient characteristics. Fifty-five patients were enrolled in a prospective study. The presence of Aspergillus in respiratory samples occurred more frequently in non-acute leukemia (AL) patients than in AL patients (P = .0003), and in patients with leukocyte counts more than 100/mm(3) (P = .002). In a logistic regression model, these 2 factors appeared to be independent, with an adjusted odds ratio of 7.14 (95% confidence interval, 1.40-36.5) for non-AL patients and an adjusted odds ratio of 6.97 (95% confidence interval, 1.33-36.5) for patients with leukocyte counts more than 100/mm(3). A positive mycologic result was also more frequent among patients with lung CT scan signs of airway-invasive disease than among other patients (P = .043). Airway-invasive signs were more frequent among non-AL patients (P = .049), whereas angioinvasive disease was more frequent among both AL patients (P = .01) and patients with leukocyte counts less than 100/mm(3) (P = .001). A concomitant pulmonary infection was identified more frequently among non-AL patients (P = .005 vs allogeneic hematopoietic stem cell transplant and P = .048 vs others). Our results suggest that different strategies for diagnosing IPA should be considered based on the underlying condition.


Asunto(s)
Aspergillus/aislamiento & purificación , Neoplasias Hematológicas/complicaciones , Aspergilosis Pulmonar Invasiva/diagnóstico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Broncoscopía , Niño , Femenino , Neoplasias Hematológicas/terapia , Humanos , Aspergilosis Pulmonar Invasiva/complicaciones , Aspergilosis Pulmonar Invasiva/microbiología , Leucemia/complicaciones , Leucemia/terapia , Recuento de Leucocitos , Modelos Logísticos , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Pulmón/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Adulto Joven
3.
Invest New Drugs ; 32(5): 795-805, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24829072

RESUMEN

Bacterial L-asparaginase (ASNase), hydrolyzing L-asparagine (Asn), is an indispensable component used in the treatment of acute lymphoblastic leukemia (ALL) and certain lymphoma entities. Native Erwinia chrysanthemi-derived ASNase (n-crisantaspase) has been approved as a second-line drug for treating patients exhibiting allergy syndromes to native and pegylated Escherichia coli-derived ASNase (EC-ASNase). However, it still induces hypersensitivity in at least 17 % of treated patients. In the present study, we investigated the pharmacological activity, immunogenicity and anti-leukemic activity of a new pegylated recombinant crisantaspase (PEG-r-crisantaspase). The results demonstrate that when compared to n-crisantaspase in vivo, PEG-r-crisantaspase maintains a complete depletion of plasma Asn for up to 72 h with a 50-fold lower dose. In mice receiving PEG-r-crisantaspase, specific antibodies against the enzyme were undetectable, indicating a lower immunogenicity of the pegylated enzyme. In vitro, PEG-r-crisantaspase exhibits similar cytotoxic effects (EC50 < 5 × 10(-4) U/mL for the most sensitive cell lines) to n-crisantaspase on various leukemia and lymphoma cells and was shown to be more efficient than EC-ASNase. Three repeated PEG-r-crisantaspase injections (2-20 U/Kg) prevented leukemia development in leukemia-bearing mice for 17 days and significantly prolonged animal survival to 7-12 days. Therefore, PEG-r-crisantaspase appears to be a promising drug candidate for ALL treatment and should be further explored in experimental and clinical trials.


Asunto(s)
Antineoplásicos , Asparaginasa , Animales , Anticuerpos/sangre , Antineoplásicos/química , Antineoplásicos/inmunología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Asparaginasa/química , Asparaginasa/inmunología , Asparaginasa/farmacología , Asparaginasa/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dickeya chrysanthemi , Femenino , Humanos , Ratones , Polietilenglicoles/química , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Med Mycol ; 51(8): 795-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23855412

RESUMEN

Candida inconspicua and Candida norvegensis are two closely related species rarely involved in invasive infections. The purpose of this study was to depict the epidemiologic and clinical characteristics of candidemia due to these emerging fluconazole less susceptible species. A retrospective analysis of the epidemiology of C. inconspicua and C. norvegensis during the period 2006-2010 was initiated in six French University hospitals. From this, demographics, clinical, diagnostic and therapeutic data of C. inconspicua or C. norvegensis candidemia were recorded and compared to the observations reported in the literature. C. inconspicua was more frequently isolated compared to C. norvegensis (ratio 2.6) but from the same preferential body sites: mainly digestive (56.4% and 48.37%, respectively, for C. inconspicua and C. norvegensis) and respiratory (26% and 28.2%, respectively). Thirteen cases of candidemia were recorded and five additional cases were found in the literature. Hematogical malignancy was the main underlying disease (n = 12). Associated factors were the presence of a vascular catheter (n = 18), broad-spectrum antibiotics (n = 15), and neutropenia (n = 14). In 13 cases (72%), prior colonization was noted before the candidemia diagnosis. Combining the results for the two species, Minimal Inhibitory Concentrations (MIC50) of amphotericin B, fluconazole, voriconazole and caspofungin were 0.125, 48, 0.25, and 0.19 mg/l, respectively. These two species must be added to the growing list of emerging Candida species poorly susceptible to fluconazole.


Asunto(s)
Candida/clasificación , Candida/aislamiento & purificación , Candidiasis/diagnóstico , Candidiasis/patología , Adulto , Anciano , Antifúngicos/farmacología , Candidiasis/epidemiología , Candidiasis/microbiología , Femenino , Francia/epidemiología , Hospitales Universitarios , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
5.
J Clin Microbiol ; 50(7): 2277-81, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22535981

RESUMEN

Dermatophytes are keratinolytic fungi responsible for a wide variety of diseases of glabrous skin, nails, and hair. Their identification, currently based on morphological criteria, is hindered by intraspecies morphological variability and the atypical morphology of some clinical isolates. The aim of this study was to evaluate matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a routine tool for identifying dermatophyte and Neoscytalidium species, both of which cause dermatomycoses. We first developed a spectral database of 12 different species of common and unusual dermatophytes and two molds responsible for dermatomycoses (Neoscytalidium dimidiatum and N. dimidiatum var. hyalinum). We then prospectively tested the performance of the database on 381 clinical dermatophyte and Neoscytalidium isolates. Correct identification of the species was obtained for 331/360 dermatophytes (91.9%) and 18/21 Neoscytalidium isolates (85.7%). The results of MALDI-TOF MS and standard identification disagreed for only 2 isolates. These results suggest that MALDI-TOF MS could be a useful tool for routine and fast identification of dermatophytes and Neoscytalidium spp. in clinical mycology laboratories.


Asunto(s)
Arthrodermataceae/aislamiento & purificación , Ascomicetos/aislamiento & purificación , Dermatomicosis/diagnóstico , Técnicas Microbiológicas/métodos , Micología/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Arthrodermataceae/química , Ascomicetos/química , Dermatomicosis/microbiología , Humanos
6.
J Clin Microbiol ; 50(3): 823-30, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22170907

RESUMEN

Early evaluation of treatment efficacy in invasive aspergillosis (IA), a leading cause of morbidity and mortality in hematological patients, remains a challenge. We conducted a prospective study to evaluate the performance of different markers in predicting the outcome of patients with IA. Both clinical and biological criteria were assessed 7, 14, 21, and 45 days after inclusion in the study, and mortality was assessed at day 60. The association between baseline data and their evolution and the day 45 response to treatment was analyzed. A total of 57 patients (4 with proven, 44 with probable, and 9 with possible aspergillosis according to the revised EORTC/MSG [European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and National Institute of Allergy and Infectious Diseases Mycoses Study Group] definitions) were included. At day 45, 30 patients (53%) were determined to be responders, 25 (44%) were nonresponders, and 2 were not able to be evaluated. Twenty patients died within the 60 days of follow-up. We found that a poor day 45 outcome was associated with patients who had high baseline serum galactomannan (GM) antigen levels and those receiving steroids at the time of IA. A consistently negative serum GM index was associated with a good outcome, and the day 14 clinical evaluation was predictive of the day 45 outcome. No association was found between Aspergillus antibodies or DNA detection and patients' outcome. We conclude that the GM index value at diagnosis of IA, GM index kinetics, and clinical evaluation at day 14 are good markers for predicting the outcome of patients with IA and should be taken into account for adapting antifungal treatment.


Asunto(s)
Biomarcadores , Aspergilosis Pulmonar Invasiva/diagnóstico , Aspergilosis Pulmonar Invasiva/patología , Pronóstico , Adolescente , Adulto , Anciano , Antifúngicos/administración & dosificación , Antígenos Fúngicos/sangre , Niño , Femenino , Galactosa/análogos & derivados , Humanos , Inmunosupresores/administración & dosificación , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Aspergilosis Pulmonar Invasiva/mortalidad , Estudios Longitudinales , Masculino , Mananos/sangre , Persona de Mediana Edad , Estudios Prospectivos , Esteroides/administración & dosificación , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
7.
J Antimicrob Chemother ; 67(9): 2131-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22678731

RESUMEN

OBJECTIVES: To determine the mechanisms responsible for fluconazole resistance in two Candida albicans isolates (CAAL2 and CAAL76) recovered from two hospitalized patients after fluconazole prophylaxis. METHODS: MICs of fluconazole and voriconazole were determined by the broth microdilution method (CLSI M27-A3), and by Etest(®) for amphotericin B. RNA expression levels of CDR1, MDR1 and ERG11 were determined by RT-PCR. Mutations in ERG11 and ERG3 were investigated by amplification and sequencing. Sterol membrane profiles were determined by gas chromatography-mass spectrometry (GC-MS). In vivo virulence was determined in a murine model of invasive candidiasis. RESULTS: Both isolates displayed azole cross-resistance and reduced susceptibility to amphotericin B, and are novel Δ(5,6)-desaturase (Erg3p) mutants. CAAL2 harbours a new amino acid substitution (L193R), whereas a 13 bp deletion leading to a truncated Erg3p (Δ366-378) was found in CAAL76. Both genetic alterations impaired Erg3p function as shown by GC-MS in these isolates (ergosterol content below 10%, and accumulation of ergosta-7,22-dienol above 40%). In vivo, in a murine model of invasive candidiasis, both CAAL2 and CAAL76 exhibited a significant trend toward reduced virulence, which seems to be linked to a reduced capacity for hyphal growth. CONCLUSIONS: These findings demonstrate the critical role of residue 193 in Erg3p function and azole resistance. We suggest that this attenuated in vivo virulence phenotype could be linked to lower potential for hyphal growth. Taken together, our findings highlight the fact that erg3 mutants must be considered in future studies aiming at investigating azole antifungal drug resistance.


Asunto(s)
Sustitución de Aminoácidos , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/enzimología , Farmacorresistencia Fúngica , Fluconazol/farmacología , Oxidorreductasas/genética , Adulto , Animales , Candida albicans/aislamiento & purificación , Candida albicans/patogenicidad , Candidiasis/microbiología , Membrana Celular/química , Quimioprevención/métodos , Femenino , Fluconazol/uso terapéutico , Cromatografía de Gases y Espectrometría de Masas , Perfilación de la Expresión Génica , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Oxidorreductasas/metabolismo , Pirimidinas/farmacología , Esteroles/análisis , Triazoles/farmacología , Virulencia , Voriconazol
8.
Haematologica ; 97(9): 1357-63, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22371177

RESUMEN

BACKGROUND: Voriconazole treatment increases early survival of allogeneic hematopoietic stem cell transplant recipients with invasive aspergillosis. We investigated whether this survival advantage translates into an increased long-term survival. DESIGN AND METHODS: This retrospective study involved all patients with an invasive aspergillosis diagnosis transplanted between September 1997 and December 2008, at the Saint-Louis Hospital, Paris, France. The primary end point was survival up to 36 months. Survival analysis before and after 12 weeks, as well as cumulative incidence analysis in a competing risk framework, were used to assess the effect of voriconazole treatment and other factors on mortality. RESULTS: Among 87 patients, 42 received first-line voriconazole and 45 received another antifungal agent. Median survival time was 2.6 months and survival rate at 36 months was 18%. Overall, there was a significant difference in the survival rates of the two groups. Specifically, there was a dramatic difference in survival rates up to ten months post-aspergillosis diagnosis but no significant difference after this time. Over the first 36 months as a whole, no significant difference in survival rate was observed between the two groups. First-line voriconazole significantly reduced aspergillosis-attributable mortality. However, first-line voriconazole patients experienced a significantly higher probability of death from a non-aspergillosis-attributable cause. CONCLUSIONS: Although the prognosis for invasive aspergillosis after stem cell transplantation has dramatically improved with the use of voriconazole, this major advance in care does not translate into increased long-term survival for these severely immunocompromised patients.


Asunto(s)
Aspergilosis/mortalidad , Aspergillus/patogenicidad , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Voriconazol/uso terapéutico , Adolescente , Adulto , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergilosis/etiología , Causas de Muerte , Niño , Preescolar , Femenino , Estudios de Seguimiento , Neoplasias Hematológicas/complicaciones , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Adulto Joven
10.
Antimicrob Agents Chemother ; 54(10): 4446-50, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20625156

RESUMEN

The outcomes for 73 invasive fusariosis patients treated with voriconazole were investigated. Patients with proven (n = 67) or probable (n = 6) infections were identified from the voriconazole clinical database (n = 39) and the French National Reference Center for Mycoses and Antifungals database (n = 34). Investigator-determined success was a complete or partial response. Survival was determined from day 1 of voriconazole therapy to the last day known alive. Patients were 2 to 79 years old (median, 43 years), and 66% were male. Identified Fusarium species (62%) were F. solani, F. moniliforme, F. proliferatum, and F. oxysporum. Underlying conditions analyzed included hematopoietic stem cell transplant (HSCT; 18%), hematologic malignancy (HM; 60%), chronic immunosuppression (CI; 12%), or other condition (OC; 10%). Infection sites were brain (5%), disseminated excluding brain (67%), lungs/sinus (15%), and other (12%). Most patients (64%) were or had recently been neutropenic (<500 cells/mm(3)). Therapy duration was 1 to 480 days (median, 57 days), with a 47% success rate. Baseline neutropenia impacted success adversely (P ≤ 0.03). Success varied by underlying condition (HSCT, 38%; HM, 45%; CI, 44%; OC, 71%) and infection site (brain, 0%; disseminated, 45%; other, 56%; lung/sinus, 64%) (P > 0.05). Combination therapy (13 patients) was no better than treatment with voriconazole alone. Overall, 59% of the patients died (49% died of fusariosis), and 90-day survival was 42%. Site of infection influenced survival (P = 0.02). Median survival (in days) by species was as follows: F. solani, 213; F. oxysporum, 112; Fusarium spp., 101; F. proliferatum, 84; F. moniliforme, 76. We conclude that voriconazole is a therapeutic option for invasive fusariosis.


Asunto(s)
Antifúngicos/uso terapéutico , Fusarium/patogenicidad , Micosis/tratamiento farmacológico , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Fusarium/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Micosis/mortalidad , Estudios Retrospectivos , Resultado del Tratamiento , Voriconazol , Adulto Joven
11.
Clin Infect Dis ; 46(10): e116-8, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18419477

RESUMEN

Trichoderma longibrachiatum, a filamentous fungus, was recently described as an emerging pathogen in immunocompromised patients. Here, we report the first case, to our knowledge, of isolated invasive lung infection by T. longibrachiatum in a patient with hematologic malignancy. The infection mimicked invasive pulmonary aspergillosis and was successfully treated with a combination of voriconazole and caspofungin.


Asunto(s)
Antifúngicos/uso terapéutico , Equinocandinas/uso terapéutico , Micosis/diagnóstico , Neutropenia/complicaciones , Neumonía/microbiología , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Trichoderma/aislamiento & purificación , Adolescente , Caspofungina , Diagnóstico Diferencial , Quimioterapia Combinada , Neoplasias Hematológicas/complicaciones , Humanos , Lipopéptidos , Masculino , Micosis/tratamiento farmacológico , Neumonía/tratamiento farmacológico , Radiografía Torácica , Tomografía Computarizada por Rayos X , Voriconazol
12.
Emerg Infect Dis ; 14(4): 557-65, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18394272

RESUMEN

Candida tropicalis is a diploid ascomycetes yeast responsible for 4%-24% of candidemia. Resistance to flucytosine is rarely described for this species but was observed for 45 (35%) of 130 C. tropicalis isolates recovered from blood cultures in the Paris area in a 4-year survey. The aims of this study were to test the hypothesis that the flucytosine-resistant isolates could represent a subgroup and to determine the relationship between epidemiologic and genomic data. Epidemiologic data and gene sequences were analyzed, and molecular typing was performed. Our results suggest that a clone of flucytosine-resistant isolates, associated with malignancies and a lower mortality than that for other C. tropicalis isolates, is widespread in the Paris area. We propose the analysis of 2 polymorphic microsatellite markers coupled with URA3 sequencing to track the clone.


Asunto(s)
Antifúngicos/farmacología , Candida tropicalis/efectos de los fármacos , Candidiasis/microbiología , Flucitosina/farmacología , Fungemia/microbiología , Candida tropicalis/clasificación , Candida tropicalis/genética , Farmacorresistencia Fúngica , Francia , Genotipo , Humanos , Repeticiones de Microsatélite , Fenotipo , Factores de Riesgo , Factores de Tiempo
13.
J Antimicrob Chemother ; 61(4): 835-7, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18218642

RESUMEN

OBJECTIVES: The objective of this work was to evaluate the in vitro activity of amphotericin B, itraconazole, voriconazole, posaconazole, caspofungin and terbinafine against clinical isolates of Scytalidium dimidiatum and Scytalidium hyalinum. METHODS: Microdilution testing was performed in accordance with the CLSI M38-A method on 17 S. dimidiatum and 15 S. hyalinum clinical isolates. RESULTS: The MIC ranges of voriconazole, posaconazole, itraconazole, terbinafine, caspofungin and amphotericin B were <0.03 to 0.5 mg/L, 0.06-2 mg/L, <0.03 to >16 mg/L, 0.06-2 mg/L, 0.06-8 mg/L and 0.06-1 mg/L, respectively. CONCLUSIONS: Amphotericin B and voriconazole exhibit the lowest MICs for Scytalidium spp. Voriconazole could be a promising agent for the treatment of these refractory infections.


Asunto(s)
Antifúngicos/farmacología , Ascomicetos/efectos de los fármacos , Micosis/microbiología , Ascomicetos/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana
14.
Nucleic Acids Res ; 34(14): 4025-35, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16914441

RESUMEN

Native chromatin IP assays were used to define changes in core histone acetylation at the lysozyme locus during developmental maturation of chicken macrophages and stimulation to high-level expression by lipo-polysaccharide. In pluripotent precursors the lysozyme gene (Lys) is inactive and there is no acetylation of core histones at the gene, its promoter or at the upstream cis-control elements. In myeloblasts, where there is a very low level of Lys expression, H4 acetylation appears at the cis-control elements but not at the Lys gene or its promoter: neither H3 nor H2B become significantly acetylated in myeloblasts. In mature macrophages, Lys expression increases 5-fold: H4, H2B and H2A.Z are all acetylated at the cis-control elements but H3 remains unacetylated except at the -2.4 S silencer. Stimulation with LPS increases Lys expression a further 10-fold: this is accompanied by a rise in H3 acetylation throughout the cis-control elements; H4 and H2B acetylation remain substantial but acetylation at the Lys gene and its promoter remains low. Acetylation is thus concentrated at the cis-control elements, not at the Lys gene or its immediate promoter. H4 acetylation precedes H3 acetylation during development and H3 acetylation is most directly linked to high-level Lys expression.


Asunto(s)
Pollos/genética , Elementos de Facilitación Genéticos , Histonas/metabolismo , Macrófagos/metabolismo , Muramidasa/genética , Acetilación , Animales , Anticuerpos , Línea Celular , Pollos/crecimiento & desarrollo , Pollos/metabolismo , Inmunoprecipitación de Cromatina , Regulación del Desarrollo de la Expresión Génica , Células Precursoras de Granulocitos/metabolismo , Histonas/inmunología , Muramidasa/metabolismo , Células Madre Pluripotentes/metabolismo , ARN Mensajero/metabolismo , Activación Transcripcional
15.
Int J Antimicrob Agents ; 30(6): 551-4, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18029149

RESUMEN

During the period January 2004 to April 2007, nine cases of breakthrough invasive aspergillosis occurred among 156 allogeneic haematopoietic stem cell transplant recipients receiving caspofungin therapy, mainly for empirical treatment of persisting fever. Voriconazole salvage therapy induced two complete responses. However, seven patients ultimately died a median of 5 weeks after diagnosis, including five patients with aspergillosis. This high incidence of breakthrough invasive aspergillosis in this patient population receiving caspofungin therapy warrants further investigation.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/prevención & control , Aspergillus/efectos de los fármacos , Farmacorresistencia Fúngica , Equinocandinas/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante Homólogo/efectos adversos , Aspergilosis/microbiología , Aspergilosis/mortalidad , Caspofungina , Humanos , Lipopéptidos , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Voriconazol
16.
J Am Acad Dermatol ; 56(1): 53-62, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17190621

RESUMEN

BACKGROUND: Scabies is a contagious skin infestation caused by the human mite Sarcoptes scabiei. The usual reference method for definitive diagnosis is ex vivo identification of the mite with microscopic examination of skin scrapings. We compared diagnostic accuracy of in vivo dermoscopic (DS) mite identification using a pocket handheld low-magnification DS with the reference method. METHODS: We conducted a prospective, nonrandomized, evaluator-blinded, noninferiority study to compare sensitivities (main outcome) and other diagnostic properties of DS and microscopic examination of skin scrapings. Among 756 patients with a presumptive diagnosis of scabies consulting in one center, 238 were sequentially submitted to the two diagnostic procedures. Three dermoscopists (one expert, two inexperienced) were involved. Diagnostic strategies using clinical skills only, DS results, and a combination of both were compared. RESULTS: Sensitivities were 91% (95% confidence interval: 86-96) for DS and 90% (95% confidence interval: 85-96) for microscopic examination of skin scrapings (P = .005 for noninferiority). Specificities were 86% (95% confidence interval: 80-92) for DS and 100% (by definition) for microscopic examination of skin scrapings. DS sensitivities were similar for the expert and inexperienced dermoscopists, whereas differences were observed in specificities. However, diagnostic accuracy of inexperienced dermoscopists steadily increased during the study. Compared with clinical-based, DS-based treatment decision rule minimized the number of false-positive and false-negative findings, whereas a treatment decision rule based on combination of clinical presumption and DS result drastically reduced the number of patients with scabies left untreated. LIMITATIONS: There is no definitive standard for ruling out the diagnosis of scabies. CONCLUSIONS: Standard DS with a handheld DS is a useful tool for diagnosing scabies, with high sensitivity, even in inexperienced hands. It greatly enhances clinical skills for making treatment decisions.


Asunto(s)
Dermoscopía , Escabiosis/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Competencia Clínica , Huevos , Epidermis/parasitología , Epidermis/ultraestructura , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sarcoptes scabiei/ultraestructura , Escabiosis/parasitología , Escabiosis/patología , Sensibilidad y Especificidad , Método Simple Ciego
17.
Sci Rep ; 5: 8068, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25626693

RESUMEN

Bacterial L-asparaginase (ASNase), hydrolyzing L-asparagine (Asn), is an important drug for treating patients with acute lymphoblastic leukaemia (ALL) and natural killer (NK) cell lymphoma. Although different native or pegylated ASNase-based chemotherapy are efficient, disease relapse is frequently observed, especially in adult patients. The neo-synthesis of Asn by asparagine synthetase (AsnS) following ASNase treatment, which involves the amino acid response and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase pathways, is believed to be the basis of ASNase-resistance mechanisms. However, AsnS expression has not emerged as an accurate predictive factor for ASNase susceptibility. The aim of this study was to identify possible ASNase sensitivity/resistance-related genes or pathways using a new asparaginase, namely a pegylated r-crisantaspase, with a focus on classic Asn-compensatory responses and cell death under conditions of Asn/L-glutamine limitation. We show that, for B-ALL cell lines, changes in the expression of apoptosis-regulatory genes (especially NFκB-related genes) are associated with ASNase susceptibility. The response of malignant NK cell lines to ASNase may depend on Asn-compensatory mechanisms and other cellular processes such as cleavage of BCL2A1, a prosurvival member of the Bcl-2 protein family. These results suggest that according to cellular context, factors other than AsnS can influence ASNase susceptibility.


Asunto(s)
Apoptosis/efectos de los fármacos , Asparaginasa/toxicidad , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Aspartatoamoníaco Ligasa/toxicidad , Línea Celular Tumoral , Humanos , Células Asesinas Naturales/citología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Linfoma/metabolismo , Linfoma/patología , Diana Mecanicista del Complejo 1 de la Rapamicina , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Complejos Multiproteicos/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , eIF-2 Quinasa/metabolismo
18.
FEMS Microbiol Lett ; 208(2): 187-96, 2002 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-11959435

RESUMEN

The molds Scytalidium dimidiatum (Nattrassia mangiferae synanamorph) and Scytalidium hyalinum are responsible for dermatomycosis in humans. We sequenced their 18S subunit ribosomal RNA gene to identify these species with molecular biology-based methods. The coding sequences differed by a single polymorphism (A in S. dimidiatum, G in S. hyalinum). Moreover, we found an insert at position 1199 in the 18S rRNA gene sequence of S. dimidiatum. Its potential secondary structure was characteristic of a group IE intron. Bioinformatic and phylogenic group IE intron analyses generated four main homogeneous clusters. The S. dimidiatum intron is original and not related with other known IE group introns.


Asunto(s)
Ascomicetos/genética , Genes Bacterianos , Genes de ARNr , ARN Ribosómico 18S/genética , Secuencia de Bases , Análisis por Conglomerados , ADN Ribosómico/metabolismo , Intrones , Hongos Mitospóricos/genética , Modelos Genéticos , Datos de Secuencia Molecular , Mutagénesis Insercional , Nucleótidos/análisis , Filogenia , Alineación de Secuencia
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