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1.
J Clin Oncol ; : JCO2301648, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38484206

RESUMEN

PURPOSE: Immunoscore (IS) is prognostic in stage III colorectal cancer (CRC) and may predict benefit of duration (6 v 3 months) of adjuvant infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX) chemotherapy. We sought to determine IS prognostic and predictive value in stage-III CRC treated with adjuvant FOLFOX or oral capecitabine and infusional oxaliplatin (CAPOX) in the SCOT and IDEA-HORG trials. METHODS: Three thousand sixty-one cases had tumor samples, of which 2,643 (1,792 CAPOX) were eligible for IS testing. Predefined cutoffs (IS-Low and IS-High) were used to classify cases into two groups for analysis of disease-free survival (3-year DFS) and multivariable-adjusted hazard ratios (mvHRs) by Cox regression. RESULTS: IS was determined in 2,608 (99.5%) eligible cases, with 877 (33.7%) samples classified as IS-Low. IS-Low tumors were more commonly high-risk (T4 and/or N2; 52.9% IS-Low v 42.2% IS-High; P < .001) and in younger patients (P = .024). Patients with IS-Low tumors had significantly shorter DFS in the CAPOX, FOLFOX, and combined cohorts (mvHR, 1.52 [95% CI, 1.28 to 1.82]; mvHR, 1.58 [95% CI, 1.22 to 2.04]; and mvHR, 1.55 [95% CI, 1.34 to 1.79], respectively; P < .001 all comparisons), regardless of sex, BMI, clinical risk group, tumor location, treatment duration, or chemotherapy regimen. IS prognostic value was greater in younger (≤65 years) than older (>65 years) patients in the CAPOX cohort (mvHR, 1.92 [95% CI, 1.50 to 2.46] v 1.28 [95% CI, 1.01 to 1.63], PINTERACTION = .026), and in DNA mismatch repair proficient than deficient mismatch repair disease (mvHR, 1.68 [95% CI, 1.41 to 2.00] v 0.67 [95% CI, 0.30 to 1.49], PINTERACTION = .03), although these exploratory analyses were uncorrected for multiple testing. Adding IS to a model containing all clinical variables significantly improved prediction of DFS (likelihood ratio test, P < .001) regardless of MMR status. CONCLUSION: IS is prognostic in stage III CRC treated with FOLFOX or CAPOX, including within clinically relevant tumor subgroups. Possible variation in IS prognostic value by age and MMR status, and prediction of benefit from extended adjuvant therapy merit validation.

2.
Bioorg Med Chem Lett ; 30(18): 127389, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32717610

RESUMEN

Emergence of antibioresistance is currently a major threat of public health worldwide. Hence there is an urge need of finding new antibacterial material. Herein, we report a simple and eco-friendly method to synthesize homo and heterodicationic ionic liquids based on quaternary phosphonium and ammonium salt. In order to investigate the structure activity relationship (SAR) we measured the MICs of a series of 16 derivatives with structural variations (nature of cations and counter-ions, size of linker and alkyl side chains as well as structural symmetry) over a range of Gram-positive and Gram-negative bacterial strains from the ESKAPE group. Some of the tested structures exhibit high antimicrobial activities (MIC = 0.5 mg/L) and are active over a wide range of bacteria from Gram-positive to Gram-negative. Overall, these results reveal the strong potential of di-cationic derivatives as antibacterial agents and the determination of activities from structural features gives decisive information for future synthesis of such di-cationic structures for biocidal purpose.


Asunto(s)
Compuestos de Amonio/química , Antibacterianos/síntesis química , Líquidos Iónicos/síntesis química , Compuestos Organofosforados/química , Alcanos/química , Antibacterianos/farmacología , Cationes Bivalentes/química , Evaluación Preclínica de Medicamentos , Humanos , Líquidos Iónicos/farmacología , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
3.
Mol Cell ; 70(1): 83-94.e7, 2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29625040

RESUMEN

Growing resistance of pathogenic bacteria and shortage of antibiotic discovery platforms challenge the use of antibiotics in the clinic. This threat calls for exploration of unconventional sources of antibiotics and identification of inhibitors able to eradicate resistant bacteria. Here we describe a different class of antibiotics, odilorhabdins (ODLs), produced by the enzymes of the non-ribosomal peptide synthetase gene cluster of the nematode-symbiotic bacterium Xenorhabdus nematophila. ODLs show activity against Gram-positive and Gram-negative pathogens, including carbapenem-resistant Enterobacteriaceae, and can eradicate infections in animal models. We demonstrate that the bactericidal ODLs interfere with protein synthesis. Genetic and structural analyses reveal that ODLs bind to the small ribosomal subunit at a site not exploited by current antibiotics. ODLs induce miscoding and promote hungry codon readthrough, amino acid misincorporation, and premature stop codon bypass. We propose that ODLs' miscoding activity reflects their ability to increase the affinity of non-cognate aminoacyl-tRNAs to the ribosome.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Proteínas Bacterianas/biosíntesis , ADN Bacteriano/genética , Infecciones por Klebsiella/tratamiento farmacológico , Subunidades Ribosómicas Pequeñas/efectos de los fármacos , Xenorhabdus/metabolismo , Aminoaciltransferasas/genética , Aminoaciltransferasas/metabolismo , Animales , Antibacterianos/metabolismo , Bacterias/genética , Bacterias/metabolismo , Proteínas Bacterianas/genética , Sitios de Unión , Modelos Animales de Enfermedad , Femenino , Células Hep G2 , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Masculino , Ratones Endogámicos ICR , Biosíntesis de Proteínas/efectos de los fármacos , Subunidades Ribosómicas Pequeñas/genética , Subunidades Ribosómicas Pequeñas/metabolismo
4.
Bioorg Med Chem Lett ; 28(5): 926-929, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29439903

RESUMEN

We report the synthesis of new mono, di and tri phosphonium ionic liquids and the evaluation of their antibacterial activities on both Gram-positive and Gram-negative bacteria from the ESKAPE-group. Among the molecules synthesized some of them reveal a strong bactericidal activity (MIC = 0.5 mg/L) for Gram-positive bacteria (including resistant strains) comparable to that of standard antibiotics. A comparative Gram positive and Gram negative antibacterial activities shows that the nature of counter-ion has no significant effects. Interestingly, the increase of phosphonium lateral chains (from 4 to 8 carbons) results in a decrease of antibacterial activities. However, the increase of the spacer length has a positive influence on the activity on both Gram-positive and Gram-negative bacteria except for E. aerogenes. Finally, the increased charge density has no effect on the Gram-positive antibacterial activities (MIC between 2 and 4 mg/L) but seems to attenuate (except for P. aeruginosa) the discrimination between Gram-positive and Gram-negative. Overall these results suggest a unique mechanism of action of these triphenylamine-phosphonium ionic liquid derivatives.


Asunto(s)
Aminas/farmacología , Antibacterianos/farmacología , Antineoplásicos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Líquidos Iónicos/farmacología , Compuestos Organofosforados/farmacología , Aminas/química , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Líquidos Iónicos/síntesis química , Líquidos Iónicos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Compuestos Organofosforados/síntesis química , Compuestos Organofosforados/química , Relación Estructura-Actividad
5.
Bioorg Med Chem Lett ; 26(15): 3770-3, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27287371

RESUMEN

Staphylococcus aureus, a Gram positive coccal bacterium is a major cause of nosocomial infection. We report the synthesis of new triphenylamine phosphonium ionic liquids which are able to self-assemble into multiwall nanoassemblies and to reveal a strong bactericidal activity (MIC=0.5mg/L) for Gram positive bacteria (including resistant strains) comparable to that of standard antibiotics. Time kill, metabolism and fluorescence confocal microscopy studies show a quasi-instantaneously penetration of the nanoassemblies inside the bacteria resulting of a rapid blocking (30min) of their proliferation. As confirmed by rezasurin reduction monitoring, these compounds strongly affect the bacterial metabolism and a Gram positive versus Gram negative selectivity is clearly observed. These fluorescent phosphonium ionic liquid might constitute a useful tool for both translocation studies and to tackle infectious diseases related to the field of implantology.


Asunto(s)
Aminas/farmacología , Antibacterianos/farmacología , Colorantes Fluorescentes/farmacología , Líquidos Iónicos/farmacología , Compuestos Organofosforados/farmacología , Aminas/síntesis química , Aminas/química , Antibacterianos/síntesis química , Antibacterianos/química , Bacterias/citología , Bacterias/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Líquidos Iónicos/síntesis química , Líquidos Iónicos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Compuestos Organofosforados/síntesis química , Compuestos Organofosforados/química , Relación Estructura-Actividad
6.
Parasit Vectors ; 9: 268, 2016 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-27151152

RESUMEN

BACKGROUND: Mosquitoes belonging to Anopheles gambiae species complex are the main malaria vector in Mauritania but data on their vector capacities, feeding habits and insecticide susceptibility are still scanty. The objectives of this study were to fill this gap. METHODS: Adult Anopheles spp. mosquitoes were collected using pyrethrum spray catch method from two ecological zones of Mauritania: Nouakchott (Saharan zone) and Hodh Elgharbi region (Sahelian zone). Circumsporozoite proteins (CSP) for P. falciparum, P. vivax VK210 and P. vivax VK247 were detected by enzyme-linked immunosorbent assay (ELISA) from the female anopheline mosquitoes. To confirm CSP-ELISA results, polymerase chain reaction (PCR) was also performed. Blood meal identification was performed in all engorged females by partial sequencing of the mitochondrial cytochrome b gene. Molecular assessments of pyrethroid knockdown resistance (kdr) and insensitive acetylcholinesterase resistance (ace-1) were conducted. RESULTS: In Nouakchott, the only species of Anopheles identified during the survey was Anopheles arabiensis (356 specimens). In Hodh Elgharbi, 1016 specimens of Anopheles were collected, including 578 (56.9%) Anopheles rufipes, 410 (40.35%) An. arabiensis, 20 (1.96%) An. gambiae, 5 (0.5%) An. pharoensis and 3 (0.3 %) An. funestus. Three of 186 female An. arabiensis collected in Nouakchott and tested by ELISA were found positive for Plasmodium vivax VK210, corresponding to a sporozoite rate of 1.6%; however PCR confirmed infection by P. vivax sporozoite in only one of these. In Hodh Elgharbi, no mosquito was found positive for Plasmodium spp. infection. There was a statistically significant difference in the percentage of human blood-fed Anopheles spp. between Nouakchott (58.7%, 47 of 80 blood-engorged An. arabiensis females) and Hodh Elgharbi (11.1%, 2 of 18 blood-engorged mosquitoes). Analysis of the kdr polymorphisms showed 48.2% (70/145) of East African kdr mutation (L1014S) in Nouakchott compared to 10% (4/40) in Hodh Elgharbi region (P < 0.001). Nevertheless, West African kdr mutation (L1014F) was found only in An. gambiae populations (4/40, 10%) from Hodh Elgharbi region. No ace-1 mutation was found in mosquito specimens from the two study zones. CONCLUSIONS: Overall, this study confirmed the autochthonous P. vivax malaria transmission in Nouakchott, involving An. arabiensis as the main vector. It also described for the first time the absence of ace-1 mutation, the co-occurrence of both West and East African kdr mutation in An. gambiae in Mauritania, and highlighted the regional variations in the prevalence and type of kdr mutations.


Asunto(s)
Anopheles/efectos de los fármacos , Conducta Alimentaria/fisiología , Resistencia a los Insecticidas , Insecticidas/farmacología , Proteínas Protozoarias/aislamiento & purificación , Distribución Animal , Animales , Anopheles/fisiología , Biodiversidad , Femenino , Mauritania , Lluvia , Estaciones del Año , Factores de Tiempo
7.
J Clin Virol ; 66: 107-11, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25866349

RESUMEN

BACKGROUND: To scan a virus (TOSV) belongs to the Phlebovirus genus within the Bunyaviridae family. TOSV is an arbovirus transmitted by sandflies. In Mediterranean countries, TOSV is one of the major viral pathogens involved in aseptic meningitis and meningoencephalitis. OBJECTIVES: Development and assessment of a new sensitive and specific real-time RT-PCR assay for TOSV diagnosis. STUDY DESIGN: TOSV-specific primers and probe targeting the S-segment of the genome were designed, based on recent TOSV sequences available in public databases. Sensitivity was assessed using 10-fold serial dilutions of a RNA transcript and serial dilutions of TOSV strains isolated from infected human beings. Specificity was determined by testing RNA extracts from closely related Phleboviruses. The assay was then used for TOSV infection diagnosis in 971 clinical samples and for TOSV detection in 2000 sandflies. RESULTS: The real-time RT-PCR assay exhibited a sensitivity of under 257 copies per reaction for the RNA transcripts and 0.0056 and 0.014 TCID50 of Italian and Spanish TOSV genotypes per reaction, respectively. No other close Phleboviruses were detected. TOSV was identified in 17 clinical samples and in 3 sandflies. CONCLUSIONS: The assay described is a rapid, robust and reliable real-time RT-PCR test for accurate diagnosis of human TOSV infection as well as for the surveillance of TOSV in vector populations.


Asunto(s)
Infecciones por Bunyaviridae/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/aislamiento & purificación , Infecciones por Bunyaviridae/virología , Femenino , Humanos , Italia , Masculino , Sensibilidad y Especificidad , España , Factores de Tiempo
8.
J Am Mosq Control Assoc ; 29(1): 81-3, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23687863

RESUMEN

Aedes albopictus was first identified in southern France in 2004, inducing an emerging risk for autochthonous transmission around imported cases of dengue or chikungunya, and also for mosquito-borne nosocomial transmission in hospitals. Aedes albopictus has been present in Marseille since September 2009 and in Aix-en-Provence since August 2010. Because of the possible admission of viremic patients with dengue or chikungunya in the hospitals of these cities, a mosquito survey was conducted in 2011 in 2 of the hospitals, with the use of mosquito traps. Aedes albopictus was detected with Eisenhans II traps and egg traps in both hospitals during the warm season.


Asunto(s)
Aedes , Infección Hospitalaria/transmisión , Dengue/transmisión , Animales , Infección Hospitalaria/prevención & control , Dengue/prevención & control , Monitoreo del Ambiente , Francia , Hospitales/estadística & datos numéricos , Humanos
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