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1.
Z Gastroenterol ; 61(7): 852-861, 2023 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-36413992

RESUMO

The immunodeficiency syndrome of functional hyposplenia/asplenia is frequently unrecognized. The gold standard procedure for the diagnosis of this disease is technetium-99m scintigraphy of heat-denatured erythrocytes and the detection of pitted erythrocytes or Howell-Jolly bodies. Initial work suggests that this clinical presentation is associated with a small spleen. The aim of this review is to describe the value of B-mode and contrast-enhanced ultrasound in the identification of immunodeficiency caused by functional hyposplenism.


Assuntos
Esplenopatias , Humanos , Esplenopatias/diagnóstico por imagem , Cintilografia , Inclusões Eritrocíticas , Ultrassonografia
2.
Mol Clin Oncol ; 13(5): 43, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32874573

RESUMO

Improving overall survival in recurrent glioblastoma remains a challenge, and drugs acting by unique mechanisms are urgently required. Ixazomib is an orally-administered proteasome inhibitor used in combination with lenalidomide and dexamethasone to treat patients with multiple myeloma who have received at least one prior therapy. However, ixazomib's ability to reach brain tumors has not been studied during its development. The aim of the present study (ClinicalTrials.gov, NCT02630030) was to establish and quantify ixazomib's presence in glioblastoma. The present study investigated 3 patients with recurrent glioblastoma after administration of oral ixazomib citrate (MLN 9708) at a fixed 4.0 mg dose within a 3-hpreoperative window. A total of 2 blood samples were taken from each patient at the time of incision, tumor sampling and closure. Brain tumor samples were collected during tumor resection. These samples were then used to measure the plasma and brain tumor tissue concentration of the biologically-active form of ixazomib (MLN 2238). Patient 1 had plasma concentrations of ixazomib averaging 26.2, 21.8 and 15.3 ng/ml at incision, tumor sampling and closure, respectively. The brain tumor tissue concentration was 7.88 ng/g. Patient 2 had the same interval and brain tumor tissue measurements of 19.0, 18.0 and 8.93 ng/ml, and 2.03 ng/g. Patient 3 had plasma concentration interval measurements of 25.6, 36.2 and 28.7 ng/ml. Multiple brain tumor tissue samples were taken in patient 3, with an average tissue ixazomib concentration of 3.37 ng/g. Ixazomib was found at plasma concentrations commensurate with its previously established pharmacokinetic profile without clinically relevant drug-related adverse events. Ixazomib reaches glioblastoma tissues at measurable concentrations at the time of tumor resection, confirming target tissue delivery. This justifies the phase I study of ixazomib in recurrent glioblastoma currently in development.

3.
Bioanalysis ; 10(22): 1803-1817, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30325202

RESUMO

Aim: A sensitive method to quantify emixustat and its rapidly formed three major deaminated metabolites in human plasma was necessary to determine exposure in clinical trials. Methods: An LC-MS/MS method was validated for accuracy and precision, linearity, carry over, selectivity, recovery, matrix effects, hematocrit effects and stability. Results: A quantitative procedure for the determination of emixustat, ACU-5116, ACU-5124 and ACU-5149 in human plasma over the concentration range of 0.0500/1.00/1.00/1.00-10.0/1000/1000/1000 ng/ml, was successfully validated and has been used to successfully analyze samples in three clinical trials. Incurred sample reanalysis was performed for all four analytes in each study with >92% of the repeat results and original results within 20% of the mean of the two values.

4.
AAPS J ; 18(2): 290-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26821803

RESUMO

The importance of appropriate sample management in regulated bioanalysis is undeniable for clinical and non-clinical study support due to the fact that if the samples are compromised at any stage prior to analysis, the study results may be affected. Health authority regulations do not contain specific guidance on sample management; therefore, as part of the Global Bioanalysis Consortium (GBC), the A5 team was established to discuss sample management requirements and to put forward recommendations. The recommendations from the team concern the entire life span of the sample and include the following: 1. Sampling procedures should be described in the protocol or within the laboratory manual. This information should include the volume of the sample to be collected, the required anticoagulant, light sensitivity, collection and storage containers, and labeling with a unique identifier. 2. The correct procedures for processing and then storing the samples after collection at the clinical/non-clinical testing site and during shipment are also very important to ensure the analyte(s) stability and should be documented. 3. Chain of custody for the samples must be maintained throughout the complete life span of each sample. This is typically maintained via paper and electronic data systems, including Laboratory Information Management Systems (LIMS) where available. 4. Pre- and post-analysis storage location and conditions must also be clearly defined at the analytical laboratory. The storage temperature of the samples must be traceable and controlled by monitoring and warning alerts. The team suggests moving away from using temperatures and to adopt standard terminology of "room temperature," "refrigerator," "freezer," and "ultra-freezer" that have defined and industry-wide accepted temperature ranges. 5. At the end of the study, documentation of the samples' disposal is required.


Assuntos
Bancos de Espécimes Biológicos/normas , Ciência de Laboratório Médico/normas , Manejo de Espécimes/normas , Congressos como Assunto/normas , Humanos , Internacionalidade , Ciência de Laboratório Médico/métodos , Manejo de Espécimes/métodos
5.
Org Lett ; 6(23): 4159-62, 2004 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-15524432

RESUMO

The de novo analysis, design, and synthesis of the azaspiracid-1 trioxadispiroketal system is described. A revised structural model was developed on the basis of an independent analysis of the NMR spectral data of the natural product that fit all of the data and the thermodynamically favored spiroketal paradigm. This model was then tested via synthesis using a novel trioxadispiroketalization process and supported by spectroscopic correlation.


Assuntos
Furanos/síntese química , Toxinas Marinhas/síntese química , Compostos de Espiro/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estereoisomerismo
6.
J Org Chem ; 67(22): 7649-55, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12398485

RESUMO

Butenolides 5a and 13 were used as optically active templates in the de novo synthesis of 4'-disubstituted nucleoside analogues. The butenolides were reduced and acylated in situ to give acetates 10 and 14. Vorbrüggen coupling gave the protected nucleoside analogues 11 and 15. Reduction of 11 gave 4'-ethoxy-2',3'-dideoxythymidine (6) and deprotection of 15 gave 4'-ethoxy-2',3'-dideoxydidehydrothymidine (7). The cis-dihydroxylation of a variety of butenolides occurred with the major product formed from oxidation of the beta-face.


Assuntos
Furanos/química , Nucleosídeos/química , Nucleosídeos/síntese química , 4-Butirolactona/análogos & derivados , Hidroxilação , Estrutura Molecular , Estereoisomerismo
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