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1.
Haematologica ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899342

RESUMO

Hematological cancers are among the most common cancers in adults and children. Despite significant improvements in therapies, many patients still succumb to the disease. Therefore, novel therapies are needed. The Wiskott-Aldrich syndrome protein (WASp) family regulates actin assembly in conjunction with the Arp2/3 complex, a ubiquitous nucleation factor. WASp is expressed exclusively in hematopoietic cells and exists in two allosteric conformations: autoinhibited or activated. Here, we describe the development of EG-011, a first-in-class small molecule activator of the WASp auto-inhibited form. EG-011 possesses in vitro and in vivo anti-tumor activity as a single agent in lymphoma, leukemia, and multiple myeloma, including models of secondary resistance to PI3K, BTK, and proteasome inhibitors. The in vitro activity was confirmed in a lymphoma xenograft. Actin polymerization and WASp binding was demonstrated using multiple techniques. Transcriptome analysis highlighted homology with drugs-inducing actin polymerization.

2.
J Labelled Comp Radiopharm ; 64(11): 440-446, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34355420

RESUMO

Radiolabelling with short half-lives radionuclides (e.g., fluorine-18 and carbon-11) must be as efficient and as fast as possible. Nucleophilic radiofluorinations and radiomethylations are conducted in polar aprotic solvents, such as dimethylsulfoxyde (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA), at high temperature. Those solvents are classified as toxic according to the ICH guidelines and must be evaluated in drug such as radiopharmaceuticals. Headspace gas chromatography is the standard method for the quantification of residual solvents but is not optimized for a rapid quantification of low vapor pressure solvents such as DMSO, DMF and DMA in radiopharmaceuticals. Direct injection gas chromatography is an interesting option without incubation step but the analysis run-time remains beyond 10 min long. In consequence, we developed a very simple ultra-high performance liquid chromatography method coupled with UV detection. Following the EMA requirements, we successfully validated a 3-min run-time analysis for quantification of three solvents in short half-lives radiopharmaceuticals. We currently use this method for the quality control of radiopharmaceuticals produced in our PET center.


Assuntos
Dimetilformamida
3.
PLoS Genet ; 10(6): e1004417, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24901252

RESUMO

Many genes important in immunity are found as multigene families. The butyrophilin genes are members of the B7 family, playing diverse roles in co-regulation and perhaps in antigen presentation. In humans, a fixed number of butyrophilin genes are found in and around the major histocompatibility complex (MHC), and show striking association with particular autoimmune diseases. In chickens, BG genes encode homologues with somewhat different domain organisation. Only a few BG genes have been characterised, one involved in actin-myosin interaction in the intestinal brush border, and another implicated in resistance to viral diseases. We characterise all BG genes in B12 chickens, finding a multigene family organised as tandem repeats in the BG region outside the MHC, a single gene in the MHC (the BF-BL region), and another single gene on a different chromosome. There is a precise cell and tissue expression for each gene, but overall there are two kinds, those expressed by haemopoietic cells and those expressed in tissues (presumably non-haemopoietic cells), correlating with two different kinds of promoters and 5' untranslated regions (5'UTR). However, the multigene family in the BG region contains many hybrid genes, suggesting recombination and/or deletion as major evolutionary forces. We identify BG genes in the chicken whole genome shotgun sequence, as well as by comparison to other haplotypes by fibre fluorescence in situ hybridisation, confirming dynamic expansion and contraction within the BG region. Thus, the BG genes in chickens are undergoing much more rapid evolution compared to their homologues in mammals, for reasons yet to be understood.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Galinhas/genética , Complexo Principal de Histocompatibilidade/genética , Animais , Sequência de Bases , Butirofilinas , Galinhas/sangue , Genoma/genética , Haplótipos/genética , Glicoproteínas de Membrana/genética , Família Multigênica/genética , Análise de Sequência de DNA , Homologia de Sequência , Sequências de Repetição em Tandem/genética
4.
Ann Work Expo Health ; 66(9): 1215-1223, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-35596678

RESUMO

OBJECTIVES: The risk of chronic exposure to antineoplastic agents in hospitals, mainly by skin contact with contaminated surfaces, is well established. The aim of this study was to assess indirectly the risk of occupational exposure to antineoplastics drugs at two hospitals by using an environmental monitoring, and to suggest ways of improving the exposure to healthcare workers. METHODS: An observational study of care practices on both sites was carried out. A wipe sampling campaign was then designed to study environmental contamination throughout the chemotherapy process: receipt, storage, compounding, transport, administration, and elimination areas. Samples were analyzed by a validated LC-MS/MS method allowing trace quantification of cyclophosphamide. A guidance 'safe value' of 0.10 ng/cm2 was considered. RESULTS: A total of 293 samples were analyzed, of which 58% were found to be positive. In the compounding units, the drug vials were contaminated before [range = (non-quantifiable [NQ]-0.71) ng/cm2] and after cleaning procedure [(NQ-0.62) ng/cm2], particularly when the flip-off lid was removed during cleaning. The contamination found on manual preparations was operator-dependent: [non-detectable (ND)-3.51] ng/cm2 on infusion bag surfaces; (780.61-24 698.98) ng/cm2 on medication ports. In the case of automated preparations, the average contamination was higher on infusion bag surfaces [(2.43-36.86) ng/cm2] and lower on medication ports [(0.43-7.65) ng/cm2] than manual preparations. Contamination of the analytical control area was also highlighted. In the daily care unit, the contamination was located near the infusion area (armchairs, infusion stands, floor, and patient toilets), and varied somewhat between the two sites, especially on the floor with (0.46-27.32) compared to (ND-0.18) ng/cm2. We did not detect contamination on the transport boxes, on the door handles or in the disposal areas. CONCLUSIONS: The variability of contamination observed between the two sites can be explained in part by the difference in routine practices, especially training of the staff, and cleaning procedures. Findings were communicated to healthcare workers, and news interventions were implemented based on wipe sampling results. This study demonstrated a method for routine environmental monitoring and worker education as a strategy to reduce occupational exposure.


Assuntos
Antineoplásicos , Neoplasias , Exposição Ocupacional , Humanos , Exposição Ocupacional/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ciclofosfamida/análise , Antineoplásicos/análise , Monitoramento Ambiental/métodos
5.
Appl Radiat Isot ; 176: 109874, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34311218

RESUMO

The radiochemical purity (RCP) determination of radiopharmaceuticals is routinely done with radio-thin layer chromatography (r-TLC). These methods are usually transposed and adjusted from the summary product characteristics without any analytical validation. The r-TLC method is simple but manually-performed steps could lead to RCP misinterpretation. To increase the sensitivity, radio ultra-high performance liquid chromatography (r-UHPLC) can be used. In this study, an r-UHPLC method had been validated and compared to the r-TLC method. Hydrolyzed-reduced technetium had also been studied.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Controle de Qualidade , Compostos Radiofarmacêuticos/química , Tecnécio/química , Cromatografia em Camada Fina/métodos
6.
Eur J Med Chem ; 226: 113895, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34624821

RESUMO

We report the synthesis of novel first-in-class 2-oxindole-based derivatives as dual PDK1-AurA kinase inhibitors as a novel strategy to treat Ewing sarcoma. The most potent compound 12 is suitable for progression to in vivo studies. The specific attributes of 12 included nanomolar inhibitory potency against both phosphoinositide-dependent kinase-1 (PDK1) and Aurora A (AurA) kinase, with acceptable in vitro ADME-Tox properties (cytotoxicity in 2 healthy and 14 hematological and solid cancer cell-lines; inhibition of PDE4C1, SIRT7, HDAC4, HDAC6, HDAC8, HDAC9, AurB, CYP1A2, CYP2C9, CYP2C19, CYP2D6, and hERG). X-ray crystallography and docking studies led to the identification of the key AurA and PDK1/12 interactions. Finally, in vitro drug-intake kinetics and in vivo PK appear to indicate that these compounds are attractive lead-structures for the design and synthesis of PDK1/AurA dual-target molecules to further investigate the in vivo efficacy against Ewing Sarcoma.


Assuntos
Antineoplásicos/farmacologia , Aurora Quinase A/antagonistas & inibidores , Desenvolvimento de Medicamentos , Oxindóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piruvato Desidrogenase Quinase de Transferência de Acetil/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Aurora Quinase A/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxindóis/síntese química , Oxindóis/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Relação Estrutura-Atividade
7.
Clin Cancer Res ; 27(14): 3876-3883, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33947696

RESUMO

PURPOSE: In BRAF V600MUT metastatic melanoma, cyclin D-CDK4/6-INK4-Rb pathway alterations are involved in resistance to MAPK inhibitors, suggesting a clinical benefit of cyclin-dependent kinase 4 (CDK4) inhibitors. In this phase I-II study, we aimed to establish the MTD of palbociclib when added to vemurafenib. PATIENTS AND METHODS: Patients with BRAF V600E/KMUT metastatic melanoma harboring CDKN2A loss and RB1 expression were included and stratified into two groups according to previous BRAF inhibitor treatment (no:strata 1; yes:strata 2). Treatment comprised palbociclib once daily for 14 days followed by a 7-day break + continuous dosing of vemurafenib. The primary endpoint was the occurrence of dose-limiting toxicity (DLT), and the secondary endpoints included the best response, survival, pharmacokinetics, and tumor molecular profiling. RESULTS: Eighteen patients were enrolled, with 15 in strata 2. Characteristics at inclusion were American Joint Committee on Cancer stage IVM1c (N = 16; 88.9%), high lactate dehydrogenase (N = 9; 50.0%), and median number of previous treatments of 2. One and 5 patients experienced DLT in strata 1 and 2, respectively, defining the MTD at palbociclib 25 mg and vemurafenib 960 mg in strata 2. No significant evidence for drug-drug interactions was highlighted. The median progression-free survival was 2.8 months, and 5 (27.8%) patients showed a clinical response. The baseline differential mRNA expression analysis and in vitro data revealed the role of CHEK2 in the response to palbociclib. CONCLUSIONS: Although the combination of palbociclib + fixed-dose vemurafenib did not allow an increased palbociclib dosage above 25 mg, a significant clinical benefit was achieved in pretreated patients with melanoma. An association between the transcriptomic data and clinical response was highlighted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quinase do Ponto de Checagem 2/fisiologia , Melanoma/tratamento farmacológico , Melanoma/genética , Piperazinas/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/genética , Piridinas/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Vemurafenib/administração & dosagem , Adulto , Feminino , Humanos , Masculino , Melanoma/secundário , Pessoa de Meia-Idade , Neoplasias Cutâneas/patologia , Resultado do Tratamento
8.
Clin Res Hepatol Gastroenterol ; 44(5): 681-691, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31964615

RESUMO

BACKGROUND: Haptoglobin bifucosylated tetra-antennary glycan have been identified in patients with early stage hepatocellular carcinoma, but its specificity according to the presence or not of cirrhosis has never been assessed. The aims of this study were to determine if haptoglobin bifucosylated tetra-antennary glycan (1) could be a marker of HCC in patients without cirrhosis; (2) could increase the performance of standard alpha-fetoprotein (AFP) or recent blood tests for HCC detection, i.e., lectin-reactive alpha-fetoprotein (AFP-L3), des-gamma-carboxy prothrombin (DCP) and Liver-Cancer-Risk-test (LCR1-test). METHODS: We retrospectively selected patients, 102 with HCC (21 without cirrhosis), matched by stages with 140 controls without HCC (81 without cirrhosis). Haptoglobin fucosylation was assessed by MALDI-TOF. LCR-glycan algorithm was constructed combining components of the LCR-1 test (haptoglobin, gammaglutamyl-transpeptidase, apolipoproteinA1, alpha-2-macroglobulin) with AFP, AFP-L3, DCP and haptoglobin bifucosylated tetra-antennary glycan. RESULTS: In 102 patients without cirrhosis (21 HCC and 81 controls), the intention-to-diagnose analyses showed that haptoglobin bifucosylated tetra-antennary glycan alone had a sensitivity of 71% (15/21;95%CI 50-86), significantly better (P=0.02) than standard AFP (43%;9/21;95%CI 24-63), and a specificity of 96% (78/81;95% 90-99). The sensitivity of LCR-glycan, in patients without cirrhosis, was 86% (18/21; 95%CI 63-95) significantly better (P=0.001) than standard AFP (43%; 9/21; 95%CI 24-63), with an AUROC of 0.943 (95%CI 0.806-0.98) compared to 0.811 (95%CI 0.630-0.908) for AFP (P=0.06). CONCLUSION: Haptoglobin bifucosylated tetra-antennary glycan is associated with the presence of HCC in patients with chronic liver disease including those without cirrhosis. Its combination with existing HCC biomarkers could improve the performance of standard AFP for HCC detection.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Haptoglobinas/análise , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Carcinoma Hepatocelular/complicações , Feminino , Fucose/metabolismo , Haptoglobinas/metabolismo , Humanos , Hepatopatias/sangue , Hepatopatias/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
J Chromatogr A ; 1109(1): 19-25, 2006 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-16388816

RESUMO

The aim of this work is to join the advantages of two different kinds of stationary phases: monolithic columns and zirconia-based supports. On the one hand, silica monolithic columns allow a higher efficiency with a lower back-pressure than traditional packed columns. On the other hand, chromatographic stationary phases based on zirconia have a higher thermal and chemical stability and specific surface properties. Combining these advantages, a zirconia monolith with a macroporous framework could be a real improvement in separation sciences. Two main strategies can be used in order to obtain a zirconia surface on a monolithic skeleton: coating or direct synthesis. The coverage by a zirconia layer of the surface of a silica-based monolith can be performed using the chemical properties of the silanol surface groups. We realized this coverage using zirconium alkoxide and we further grafted n-dodecyl groups using phosphate derivatives. Any loss of efficiency was observed and fast separations have been achieved. The main advance reported in this paper is related to the preparation of zirconia monoliths by a sol-gel process starting from zirconium alkoxide. The synthesis parameters (hydrolysis ratio, porogen type, precursor concentration, drying step, etc.) were defined in order to produce a macroporous zirconia monoliths usable in separation techniques. We produced various homogeneous structures: zirconia rod 2 cm long with a diameter of 2.3 mm, and zirconia monolith inside fused silica capillaries with a 75 microm I.D. These monoliths have a skeleton size of 2 microm and have an average through pore size of 6 microm. Several separations have been reported.


Assuntos
Cromatografia Líquida/instrumentação , Zircônio/química , Aminas/isolamento & purificação , Derivados de Benzeno/isolamento & purificação , Cromatografia Líquida/métodos , Microscopia Eletrônica de Varredura , Dióxido de Silício , Propriedades de Superfície
10.
Carbohydr Polym ; 112: 145-51, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25129728

RESUMO

N-Butyl-phosphorotriamide (NBPT) is a fertilizer widely used for its urease inhibiting properties. Nevertheless, formulations currently commercialized are complex and do not avoid severe decrease of activity due to the low stability of the bioactive compound under acidic conditions. According to its structure, NPBT was thought to be able to interact with both polar additives, by its phosphoramide function, and hydrophobic ones, through its alkyl chain. In this context, and in order to simplify formulations of this bioactive compound, a panel of natural polysaccharides was studied, including starch, ß-(1,3)-glucans, carraghenans and alginates. We also used cyclodextrins, characterized the most stable inclusion complex with α-cyclodextrin and evaluated the stability of NBPT thus protected against hydrolysis under acidic conditions.


Assuntos
Ciclodextrinas/química , Inibidores Enzimáticos/química , Compostos Organofosforados/química , Polissacarídeos/química , Urease/antagonistas & inibidores , Alginatos/química , Sequência de Carboidratos , Carragenina/química , Fertilizantes , Glucanos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Amido/química , alfa-Ciclodextrinas/química
11.
J Chromatogr A ; 1217(9): 1496-500, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20079499

RESUMO

Monolithic capillary columns based on zirconia were prepared directly from zirconium alkoxide. They were also prepared coating a classical silica based monolithic column with zirconium butoxide. Using the gradual evolution of the theophylline/caffeine separation factor, it was found that successive zirconia coatings produced the progressive fading of surface silanols replaced by Zr-OH groups. The behavior of a silica monolith coated four times with zirconium butoxide was very similar to that of a pure zirconia monolith. The dramatic change in xanthine separation factor observed with zirconia stationary phases and the theophylline and caffeine probe solutes was used to develop a complete separation of xanthines on zirconia stationary phase in less than 6 min. The three dimethylxanthine isomers, theophylline, theobromine and paraxanthine, are very difficult to separate in RPLC with classical C18 stationary phases. The three isomers were easily separated in HILIC mode on a zirconia based stationary phase.


Assuntos
Cromatografia Líquida/instrumentação , Xantinas/isolamento & purificação , Zircônio/química , Cafeína/isolamento & purificação , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Concentração Osmolar , Dióxido de Silício/química , Teofilina/isolamento & purificação , Água/química , Xantinas/química
12.
Anal Chem ; 77(13): 4071-80, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15987112

RESUMO

Room temperature ionic liquids (RTIL) are molten salts starting to be used as nonmolecular solvents in separation methods mainly for their extremely low vapor pressure and thermal stability. RTILs are formed by an anion associated to a cation. This intrinsic structure gives them a dual nature. When used as additives in RPLC mobile phases to enhance basic compound separation, RTILs lose their particular physicochemical properties to become just salts. However, a given RTIL is not equivalent to another one made with the same cation. It is shown that both the anion and the cation contribute to solute retention and peak efficiency extending beyond simple "salting-out" or ion-pairing effects. Nine different alkyl-methyl-imidazolium ionic liquids with different alkyl chain length and chloride or BF(4-) or PF(6-) anions were used as additives (50 mM max. conc.) in the liquid chromatography separation of some cationic basic solutes on a Kromasil C18 column. It is shown with sodium salts and an acetonitrile-water 30/70 v/v mobile phase that anions can adsorb on the stationary phase surface according to their lyotropic character. They can also form ion pairs with the cationic basic solutes. Alkyl-imidazolium cations also adsorb on the C18 bonded stationary phase due to hydrophobic character depending on their alkyl chain length. Anion adsorption dramatically increases the cationic solute retention factors when cation adsorption decreases them. The cation adsorption is mainly responsible for peak shape and efficiency enhancements. RTILs are additives that enhance the basic cationic solute peak shape changing peak position. A wise choice of the appropriate combination of anion lyotropy with imidazolium cation hydrophobicity allows playing with solute selectivity and analysis duration.

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