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1.
Cureus ; 16(5): e60522, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38883070

RESUMEN

Suboptimal teamwork in the operating room (OR) is a contributing factor in a significant proportion of preventable complications for surgical patients. Specifying behaviour is fundamental to closing evidence-practice gaps in healthcare. Current teamwork interventions, however, have yet to be synthesized in this way. This scoping review aimed to identify actionable strategies for use during surgery by mapping the existing literature according to the Action, Actor, Context, Target, Time (AACTT) framework. The databases MEDLINE (Medical Literature Analysis and Retrieval System Online), Embase, Cumulated Index to Nursing and Allied Health Literature (CINAHL), Education Resources Information Center (ERIC), Cochrane, Scopus, and PsycINFO were searched from inception to April 5, 2022. Screening and data extraction were conducted in duplicate by pairs of independent reviewers. The search identified 9,289 references after the removal of duplicates. Across 249 studies deemed eligible for inclusion, eight types of teamwork interventions could be mapped according to the AACTT framework: bundle/checklists, protocols, audit and feedback, clinical practice guidelines, environmental change, cognitive aid, education, and other), yet many were ambiguous regarding the actors and actions involved. The 101 included protocol interventions appeared to be among the most actionable for the OR based on the clear specification of ACCTT elements, and their effectiveness should be evaluated and compared in future work.

3.
Soins ; 68(878): 25-28, 2023 Sep.
Artículo en Francés | MEDLINE | ID: mdl-37657866

RESUMEN

Encephalic death is a rare and unique pathophysiological process. Its diagnosis and management in the intensive care unit, which are well codified, determine the possibility and short- and long-term outcome of organ and tissue transplants.

4.
Eur J Med Chem ; 227: 113914, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34695774

RESUMEN

The synthesis and in vitro anti-HIV activity of a novel series of pronucleotides are reported. These prodrugs were characterized by a phosphorodithiolate structure, incorporating two O-pivaloyl-2-oxyethyl substituents as biolabile phosphate protections. The compounds were obtained following an original one-pot three-step procedure, involving the formation of a phosphorodithioite intermediate which is in situ oxidized. In vitro, comparative anti-HIV evaluations demonstrate that such original prodrugs are able to allow the efficient intracellular release of the corresponding 5'-mononucleotide. The pronucleotide of 2',3'-dideoxyadenosine (ddA) 3 exhibited a very potent antiretroviral effect with 50% effective concentration (EC50) values in nanomolar concentration range in various cell lines. In primary monocytes/macrophages, this derivative was 500 times more potent in inhibiting HIV replication (EC50 0.23 pM) than ddA and the selectivity index of the prodrug is fifty times higher than the one of the parent nucleoside.


Asunto(s)
Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Nucleósidos/farmacología , Profármacos/farmacología , Compuestos de Sulfhidrilo/farmacología , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Nucleósidos/síntesis química , Nucleósidos/química , Profármacos/síntesis química , Profármacos/química , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química , Replicación Viral/efectos de los fármacos
5.
Anal Bioanal Chem ; 407(19): 5747-58, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25998135

RESUMEN

The cytosolic 5'-nucleotidase (cN-II) has been shown to be involved in the response of cancer cells to cytotoxic agents, and the quantification of its activity in biological samples is of great interest. In this context, we developed and validated an analytical method for determination of cN-II activity in cultured cancer cells. This non-radioactive method, using a Hypercarb column as stationary phase, was validated with a lower limit of quantification of 0.1 µM inosine. We used it to characterize cell line models with modified cN-II expression obtained with stable transfections. We show that the short hairpin RNA (shRNA)-mediated inhibition of cN-II expression in various malignant blood cells is associated with decreased protein expression and enzymatic activity (1.7-6.2-fold) as well as an increased sensitivity to cytotoxic agents (up to 14-fold). On the other hand, expression of green fluorescent protein (GFP)-fused wild type or hyperactive mutant (R367Q) cN-II increased the activity and also decreased the sensitivity to nucleoside analogues. Our results confirm the biological relevance of modulating cN-II in cancer cells, and we present a straightforward validated method for the determination of cN-II activity in cellular samples.


Asunto(s)
5'-Nucleotidasa/metabolismo , Neoplasias/enzimología , 5'-Nucleotidasa/genética , Estudios de Casos y Controles , Ciclo Celular , Cromatografía Liquida , Expresión Génica , Humanos , Neoplasias/genética , Neoplasias/patología , Espectrometría de Masas en Tándem , Transfección , Células Tumorales Cultivadas
6.
Anal Bioanal Chem ; 406(12): 2925-41, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24633509

RESUMEN

An analytical method coupling online solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to quantify 16 endogenous nucleoside mono- and triphosphates in cellular samples. Separation was achieved on a porous graphitic carbon (PGC) column without ion-pairing agent in the mobile phase. Low levels of the ion-pairing agent diethylamine (DEA) added to the reconstitution solution were necessary to prevent peak tailing of nucleoside triphosphates. The mass spectrometer, a triple quadrupole with an electrospray ionisation source, was operated in positive mode. Two multiple reaction monitoring (MRM) segments were programmed, each an internal standard. Extraction and separation of nucleoside mono- and triphosphates were obtained within 20 min. The total duration of a single run was 37 min. Calibration curves, performed with labelled nucleotides added to the sample matrix, ranged from 0.29 to 18.8 pmol injected for deoxyribonucleotides and from 3.9 to 3,156 pmol for ribonucleotides. Accuracy did not deviate more than -14.6 and 10.2 % from nominal values for all compounds at all levels. CV results were all lower than 17.0 % for the LLOQ level and 14.6 % for the other levels. Quality control (QC) samples were also in agreement with acceptance criteria, except for the lower QC of GMP. Ion suppression, matrix effect, extraction recoveries and stability were assessed. After validation, the method was applied to the evaluation of the effects of gemcitabine and hydroxyurea on nucleotide pools in Messa cells.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Nucleósidos/química , Nucleósidos/aislamiento & purificación , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Automatización/métodos , Línea Celular Tumoral , Humanos , Espectrometría de Masa por Ionización de Electrospray/métodos
7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(30): 3831-40, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19805008

RESUMEN

In this study, we developed a new method for the simultaneous determination of eight endogenous ribonucleoside triphosphates and deoxyribonucleoside triphosphates based on a combination of a selective sample preparation and an ion-pair liquid chromatography-electrospray tandem mass spectrometry. The sample preparation was based on a protein precipitation coupled with a solid phase extraction using a weak-anion-exchange cartridge. The analytical separation of the nucleotides was achieved on a porous graphitic carbon stationary phase with a binary elution gradient program employing ion-pairing reagents (diethylamine and hexylamine) and organic eluent (methanol). The triple quadrupole mass spectrometer operated in both negative and positive multiple reaction monitoring modes. The calibration assay used the stable isotope labelled analogs of each compounds as standard. Standard calibrations were from 0.25 to 10pmol injected according to deoxyribonucleotides and from 12.5 to 3000pmol injected according to ribonucleotides. The within-run precision of the assay was less than 14.5% and the between-run precision was less than 12.4% for each analytes. Assay accuracy was in the range of 92.3-107.6%. This method allows the determination of NTP and dNTP pools from lysats of several cell lines or peripheral blood mononuclear cell from patient. Assays were performed with different preparation of cells to confirm the quality and the relevance of the described method.


Asunto(s)
Cromatografía Liquida/métodos , Nucleótidos/química , Espectrometría de Masas en Tándem/métodos , Línea Celular , Desoxirribonucleósidos/química , Humanos
8.
Bioorg Med Chem ; 17(17): 6340-7, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19674903

RESUMEN

Despite the unquestionable therapeutic interest of bis(SATE) pronucleotides, a presystemic metabolism preventing the delivery of the prodrugs in target cancer cells or tumours may constitute a limitation to the in vivo development of such derivatives. In order to overcome these drawbacks several strategies have been envisaged and we report herein the application of the S-acyl-2-thioethyl (SATE) phenyl pronucleotide approach to the well-known cytotoxic nucleoside cytosine-1-beta-D-arabinofuranoside (cytarabine, araC). We describe modifications of the SATE moieties with the introduction of polar groups on the acyl residue, in order to study how these changes affect antitumoral activity and metabolic stability. Two different synthetic pathways were explored and lead to obtain the corresponding mixed derivatives in satisfactory yields. Cytotoxicity was studied in murine leukaemia cells L1210 as well as in cells derived from solid human tumours (Messa and MCF7). Biological evaluation of these compounds in cell culture experiments with nucleoside analogue-sensitive and resistant cell lines showed that the modified compounds were active at higher concentrations than unmodified cytarabine, yet were much able to partially reverse resistance due to deficient nucleoside transport or activation. These results can be correlated with an incomplete decomposition mechanism into the corresponding 5'-mononucleotide.


Asunto(s)
Antineoplásicos/química , Citarabina/análogos & derivados , Profármacos/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/toxicidad , Línea Celular Tumoral , Citarabina/síntesis química , Citarabina/toxicidad , Humanos , Ratones , Profármacos/síntesis química , Profármacos/toxicidad
9.
Biomed Chromatogr ; 23(11): 1160-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19444806

RESUMEN

Using a column-switching HPLC method previously described, we studied the behavior of some mononucleotide prodrugs (pronucleotides) of 3'-azido-2',3'-dideoxythymidine in various biological media. From UV data, this method allowed quantification of transient metabolites resulting from prodrug bioconversion. The kinetic data related to the successive steps were calculated according to pseudo-first-order kinetic models and optimized using mono- or poly-exponential regressions. Various metabolites were identified by co-injection with authentic samples and/or ESI-MS coupling. The results led us to propose, for each considered pronucleotide, a global decomposition pathway ending in the selective delivery of the corresponding mononucleotide. Associated to the determination of other parameters (lipophilicity, aqueous solubility), the present study contributes to the search of suitable pharmacological properties for further in vivo evaluations.


Asunto(s)
Productos Biológicos/metabolismo , Didesoxinucleótidos/análisis , Didesoxinucleótidos/metabolismo , Profármacos/análisis , Profármacos/metabolismo , Nucleótidos de Timina/análisis , Nucleótidos de Timina/metabolismo , Zidovudina/análogos & derivados , Cromatografía Liquida , Estabilidad de Medicamentos , Espectrometría de Masas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida , Solubilidad , Zidovudina/análisis , Zidovudina/metabolismo
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(14-15): 1417-25, 2009 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-19328748

RESUMEN

A method was developed for the quantification of araCTP, CTP and dCTP in a human follicular lymphoma cell line. This method involves solid phase extraction (SPE) using a weak anion-exchanger (WAX) cartridge, a porous graphitic carbon high-performance liquid chromatography (HPLC) column separation, and tandem mass spectrometry (MS/MS) detection. By using a triple quadrupole mass spectrometer operating in negative ion multiple reaction monitoring (MRM) mode, the method was able to achieve a lower limit of quantification (LLOQ) of 0.1 microg mL(-1) for araCTP and of 0.01 microg mL(-1) for both CTP and dCTP. The method was validated and used to determine the amount of araCTP, CTP and dCTP formed after incubation of araC and an araCMP prodrug in the human follicular lymphoma cell line RL.


Asunto(s)
Trifosfato de Arabinofuranosil Citosina/química , Cromatografía Líquida de Alta Presión/métodos , Citidina Trifosfato/química , Nucleótidos de Desoxicitosina/química , Linfoma Folicular/química , Espectrometría de Masas en Tándem/métodos , Tionucleótidos/química , Línea Celular Tumoral , Humanos , Sensibilidad y Especificidad
11.
Bioorg Med Chem ; 16(15): 7321-9, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18585917

RESUMEN

Synthesis, in vitro anti-HIV activity, stability studies as well as potential for oral absorption of some novel phenyl S-acyl-2-thioethyl (SATE) phosphotriester derivatives of AZT (zidovudine; 3'-azido-2',3'-dideoxythymidine) are described herein. These pronucleotides are characterized by the presence of polar functions on the SATE biolabile phosphate protections. Whereas derivatives incorporating an amino residue in the vicinity of the thioester functionality display low chemical stability, the introduction of one or two hydroxyl groups on the SATE moieties confers high resistance of the resulting prodrugs towards esterase hydrolysis. Thus, one of these pronucleotides, the monohydroxylated SATE derivative of AZT 2, is able to cross a Caco-2 cell monolayer mainly in intact form, probing that further development is warranted as a possible HIV-pronucleotide candidate.


Asunto(s)
Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Zidovudina/química , Zidovudina/farmacología , Células CACO-2 , Humanos , Estructura Molecular , Relación Estructura-Actividad
12.
J Chromatogr A ; 1111(2): 139-46, 2006 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-16569572

RESUMEN

The possibility of using capillary electrophoresis as an alternative technique to HPLC for the separation of pronucleotide diastereoisomers of AZT was investigated. In the pH range 6.2-7.2 where the analytes are stable, a chiral additive, carboxymethyl-beta-CD, was found appropriate to enable the separation of the uncharged diastereoisomers. An experimental design strategy was used to study the influence of several parameters (CD and phosphate buffer concentration, methanol content of the electrolyte, injected volume, capillary length, electric field and separation temperature) on the separation and find suitable analytical conditions for monitoring the prodrugs in cell extracts. The diastereoisomers of the three tBuSATE phenylphosphotriester derivatives of AZT studied could be fully resolved within short analysis time (less than 10 min). Method validation results showed satisfactory results for linearity, accuracy and repeatability.


Asunto(s)
Ciclodextrinas/química , Electroforesis Capilar/métodos , Zidovudina/aislamiento & purificación , Tampones (Química) , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estereoisomerismo , Zidovudina/química
13.
Eur J Med Chem ; 40(12): 1255-61, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16095761

RESUMEN

Chitin synthase is an enzyme involved in the biosynthesis of chitin, a major structural component of the cell wall of many fungi. Since chitin is absent in vertebrates, chitin synthase has been envisaged as a valuable target in the search for new antifungal agents. In this report, a series of C-2 substituted polyhydroxypyrrolidines were designed and synthesized with the aim of mimicking the glycosylation involved at the transition state of the enzymatic reaction governed by chitin synthase. Some of these models displayed chitin synthase inhibition in the millimolar range. However, no significant antifungal activity was noted on a panel of fungal strains.


Asunto(s)
Quitina Sintasa/antagonistas & inhibidores , Iminoazúcares/síntesis química , Iminoazúcares/farmacología , Pirrolidinonas/síntesis química , Pirrolidinonas/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Quitina Sintasa/química , Hongos/efectos de los fármacos , Glicosilación , Iminoazúcares/química , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Pirrolidinonas/química , Estereoisomerismo , Relación Estructura-Actividad
14.
Bioorg Med Chem ; 12(6): 1393-402, 2004 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15018912

RESUMEN

A new enzyme-labile group called S-acyl-3-thiopropyl group (SATP) has been synthesized from allylic esters of phosphonate. After demonstration of the enzyme-labile character of the SATP in cellular extracts, it has been introduced onto the phosphonate moiety of PFA (Foscarnet) to obtain potential lipophilic prodrugs. To ponder the lipophilicity of the triesters of PFA, esters of monomethylether of polyethyleneglycols and of thioglycerol were introduced on the PFA carboxylate moiety. The SATP groups were introduced in an attempt to deliver PFA after bioactivation inside the cells. The PFA prodrugs were evaluated in vitro for their activity against human immunodeficiency viruses (HIV-1 and HIV-2).


Asunto(s)
Fármacos Anti-VIH/síntesis química , Antivirales/síntesis química , Foscarnet/análogos & derivados , Foscarnet/síntesis química , Glicerol/análogos & derivados , Profármacos/síntesis química , Compuestos de Sulfhidrilo/síntesis química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Antivirales/química , Antivirales/farmacología , Ácidos Carboxílicos/química , Ácidos Carboxílicos/metabolismo , Estudios de Evaluación como Asunto , Foscarnet/farmacología , Glicerol/química , VIH-1/efectos de los fármacos , VIH-2/efectos de los fármacos , Humanos , Técnicas In Vitro , Organofosfonatos/metabolismo , Polietilenglicoles/química , Profármacos/química , Profármacos/farmacología , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/farmacología
15.
Bull Cancer ; 90(4): 319-25, 2003 Apr.
Artículo en Francés | MEDLINE | ID: mdl-12801815

RESUMEN

The aim of this work, synthesized from personal case reports and a review of literature is to describe cutaneous complications of radiation therapy (except radiation-induced cancers): known and frequent such as radiation dermatitis or less frequent, beginning or strictly limited on irradiated skin areas: acne, infectious diseases, dyskeratosis, Grover's disease, sub-cutaneous pustulosis, cutaneous lichen, morphea, autoimmune bullous dermatosis, subacute cutaneous lupus erythematosus. Furthermore, we try to precise the physiopathogenic mechanisms of these dermatosis and we want to draw the attention on these dermatoses which sometimes need a multidisciplinary approach.


Asunto(s)
Radiodermatitis/etiología , Piel/efectos de la radiación , Enfermedad Aguda , Cateterismo Cardíaco/métodos , Dermatosis de la Mano/patología , Humanos , Células de Langerhans/efectos de la radiación , Lupus Eritematoso Cutáneo/etiología , Lupus Eritematoso Cutáneo/patología , Melanocitos/efectos de la radiación , Penfigoide Ampolloso/etiología , Penfigoide Ampolloso/patología , Pénfigo/etiología , Pénfigo/patología , Radiodermatitis/patología , Radiodermatitis/terapia
16.
Semin Oncol ; 30(2): 216-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12720139

RESUMEN

Data on clinical features observed in patients with Waldenstrom's macroglobulinemia (WM) during follow-up remain limited. Therefore, we evaluated 860 follow-up procedures in 101 patients. Median age was 66 years and 5-year overall survival 72%, with a median follow-up of 36 months in surviving patients. Sixteen patients presented at diagnosis with two or three cytopenias lasting for at least 3 months (multiple cytopenias [MC]), and MC improved after treatment in eight patients, 4 to 18 months later. MC was observed during at least 6 consecutive months in 23 other patients, 2 to 73 months (median, 24) after diagnosis. MC occurred off-therapy in 12 patients, and on-therapy in 11. Regression occurred in three of the former patients, and in seven of the latter (6 to 24 months after completion of treatment; median, 7). Finally, the 4-year estimated cause-specific cumulative incidence was 40% in the 101 patients. A second malignancy was observed in 11 patients, histological transformation in three, and rapid rise of M-component in only six patients. In conclusion, the present analysis pointed out a high incidence of long lasting MC during the evolution of WM, and a low frequency of rapid rise of M component.


Asunto(s)
Macroglobulinemia de Waldenström/complicaciones , Macroglobulinemia de Waldenström/mortalidad , Adulto , Anciano , Antineoplásicos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia , Macroglobulinemia de Waldenström/tratamiento farmacológico , Macroglobulinemia de Waldenström/fisiopatología
17.
J Med Chem ; 46(5): 782-93, 2003 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-12593658

RESUMEN

The synthesis, antiviral activity, and stability study of phosphotriester derivatives of 3'-azido-2',3'-dideoxythymidine (AZT) bearing modified l-tyrosinyl residues are reported. These compounds were obtained via phosphoramidite (P(III)) chemistry from the appropriate aryl precursors. All the derivatives were evaluated for their in vitro anti-HIV activity, and they appeared to be potent inhibitors of HIV-1 replication in various cell culture experiments, with EC(50) values between the micro- and nanomolar range, especially in thymidine kinase deficient (TK(-)) cells, showing their ability to act as mononucleotide prodrugs. The proposed decomposition process of these mixed mononucleoside aryl phosphotriesters successively involves an esterase and a phosphodiesterase hydrolysis.


Asunto(s)
Fármacos Anti-VIH/síntesis química , Organofosfatos/síntesis química , Sulfuros/síntesis química , Zidovudina/análogos & derivados , Zidovudina/síntesis química , Fármacos Anti-VIH/farmacología , Extractos Celulares , Línea Celular , Cromatografía Líquida de Alta Presión , VIH-1/efectos de los fármacos , Humanos , Hidrólisis , Cinética , Organofosfatos/farmacología , Espectrometría de Masa por Ionización de Electrospray , Sulfuros/farmacología , Replicación Viral , Zidovudina/farmacología
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