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3.
Front Med (Lausanne) ; 10: 1271540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841002

RESUMO

Introduction: Venovenous extracorporeal membrane oxygenation (V-V ECMO) can be considered in critically ill patient in severe pulmonary failure. However, the mobilization of patients on V-V ECMO can be challenging due to logistic and safety concerns. This study aimed to investigate whether 30 days survival was improved in patients who were mobilized during V-V ECMO support. Methods: We conducted a retrospective cohort all-comer study that included all patients cannulated for V-V ECMO at a single center. Patients with a V-V ECMO duration below 24 h were excluded from the analysis. The patients were grouped based on the ICU mobility scale documented during V-V ECMO support. The primary endpoint was 30 days survival, and secondary endpoints included weaning from ECMO and mechanical ventilation, as well as hospital survival. Results: A total of 343 patients were included in the study, with a median age of 56 years and 32% were female. Among them, 28% had chronic lung disease. The ICU mobilization scale ≥2 during ECMO was documented in 62/343 (18%) patients. There were no significant differences in age, gender and preexisting lung disease. Duration of ICU stay (13.1 vs. 15.6 days), time on ECMO (186 vs. 190 h) and mechanical ventilation (11.2 vs. 13.6 days) were slightly shorter in patients with ICU mobility scale <2 compared to those with ≥2 (all p = 0.0001). However, patients with ICU mobilization scale ≥2 showed significantly better 30 days survival (71.0 vs. 48.0%, OR 2.6 (1.5 to 4.8), p = 0.0012) compared to those with <2. In the ≥2 mobility scale group, a significantly higher number of patients were successfully weaned from the ventilator (61.3 vs. 46.6%, OR 1.8 (1.0 to 3.2), p = 0.049). A stronger correlation was observed between more intense mobilizations, such as being in a standing position (OR 5.0 (1.7 to 14.0), p = 0.0038), and higher 30 days survival. Conclusion: The findings of this study suggest that active mobilization during V-V ECMO support is associated with improved 30 days survival and successful weaning from the respirator. Incorporating mobilization as part of the therapeutic approach during ECMO support may offer potential benefits for critically ill patients.

4.
Artif Organs ; 47(10): 1654-1662, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37358935

RESUMO

BACKGROUND: Mobilization is important in longer courses in intensive care unit (ICU), typical for patients requiring venovenous extracorporeal membrane oxygenation (V-V ECMO). For patients supported with ECMO, especially out-of-bed mobilizations improve outcome. We hypothesized that utilization of a dual lumen cannula (DLC) for V-V ECMO would facilitate out-of-bed mobilization compared to single lumen cannulas (SLC). METHODS: Retrospective single center registry study including all V-V ECMO patients cannulated between 10/2010 and 05/2021 for respiratory failure. RESULTS: The registry included 355 V-V ECMO patients (median age 55.6 years, 31.8% female, 27.3% with preexisting pulmonary disease), 289/355 (81.4%) primary cannulated with DLC, and 66/355 (18.6%) using SLC. Both groups had similar pre-ECMO characteristics. The runtime of the first ECMO cannula was significantly longer in DLC compared to SLC (169 vs. 115 h, p = 0.015). The frequency of prone positioning during V-V ECMO was similar in both groups (38.4 vs. 34.8%, p = 0.673). There was no difference in in-bed mobilization (41.2 vs. 36.4%, for DLC and SLC, respectively, p = 0.491). Patients with DLC were more often mobilized out-of-bed (25.6 vs. 12.1%, OR 2.495 [95% CI 1.150 to 5.268], for DLC and SLC, respectively, p = 0.023). Hospital survival was similar in both groups (46.4 vs. 39.4%, for DLC and SLC, respectively, p = 0.339). CONCLUSION: Patients cannulated with a dual lumen cannula for V-V ECMO support were significantly more often mobilized out-of-bed. Since mobilization is important in prolonged ICU courses typical for ECMO patients, this might be an important benefit. Other benefits of DLC were the longer runtime of the initial cannula set and fewer suction events.


Assuntos
Oxigenação por Membrana Extracorpórea , Insuficiência Respiratória , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Oxigenação por Membrana Extracorpórea/efeitos adversos , Estudos Retrospectivos , Cateterismo , Cânula , Insuficiência Respiratória/terapia
5.
Pharmaceutics ; 14(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36297674

RESUMO

Evidence-based pain therapy should rely on precisely defined and personalized criteria. This includes balancing the benefits and risks not only of single drugs but often requires complex between-drug comparisons. Non-steroidal anti-inflammatory drugs (NSAIDs) have been available for several decades and their use is described in an abundance of guidelines. Most of these guidelines recommend that 'the selection of a particular NSAID should be based on the benefit-risk balance for each patient'. However, head-to-head studies are often lacking or of poor quality, reflecting the lower standards for clinical research and regulatory approval at the time. The inconsistency of approved indications between countries due to national applications adds to the complexity. Finally, a fading research interest once drugs become generic points to a general deficit in the post-marketing evaluation of medicines. Far from claiming completeness, this narrative review aimed to illustrate the challenges that physicians encounter when trying to balance benefits and risks in a situation of incomplete and inconsistent data on longstanding treatment concepts. Ibuprofen and mefenamic acid, the most frequently sold NSAIDs in Austria, serve as examples. The illustrated principles are, however, not specific to these drugs and are generalizable to any comparison of older drugs in daily clinical practice.

6.
Front Aging Neurosci ; 12: 185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848697

RESUMO

The vascular endothelium in the brain is an essential part of the blood-brain-barrier (BBB) because of its very tight structure to secure a functional and molecular separation of the brain from the rest of the body and to protect neurons from pathogens and toxins. Impaired transport of metabolites across the BBB due to its increasing dysfunction affects brain health and cognitive functioning, thus providing a starting point of neurodegenerative diseases. The term "cerebral metabolic syndrome" is proposed to highlight the importance of lifestyle factors in neurodegeneration and to describe the impact of increasing BBB dysfunction on neurodegeneration and dementia, especially in elderly patients. If untreated, the cerebral metabolic syndrome may evolve into dementia. Due to the high energy demand of the brain, impaired glucose transport across the BBB via glucose transporters as GLUT1 renders the brain increasingly susceptible to neurodegeneration. Apoptotic processes are further supported by the lack of essential metabolites of the phosphocholine synthesis. In Alzheimer's disease (AD), inflammatory and infectious processes at the BBB increase the dysfunction and might be pace-making events. At this point, the potentially highly relevant role of the thrombocytic amyloid precursor protein (APP) in endothelial inflammation of the BBB is discussed. Chronic inflammatory processes of the BBB transmitted to an increasing number of brain areas might cause a lasting build-up of spreading, pore-forming ß-amyloid fragments explaining the dramatic progression of the disease. In the view of the essential requirement of an early diagnosis to investigate and implement causal therapeutic strategies against dementia, brain imaging methods are of great importance. Therefore, status and opportunities in the field of diagnostic imaging of the living human brain will be portrayed, comprising diverse techniques such as positron emissions tomography (PET) and functional magnetic resonance imaging (fMRI) to uncover the patterns of atrophy, protein deposits, hypometabolism, and molecular as well as functional alterations in AD.

7.
Eur J Med Chem ; 121: 132-142, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27236069

RESUMO

Ligand conjugation to oligonucleotides is an attractive strategy for enhancing the therapeutic potential of antisense and siRNA agents by inferring properties such as improved cellular uptake or better pharmacokinetic properties. Disulfide linkages enable dissociation of ligands and oligonucleotides in reducing environments found in endosomal compartments after cellular uptake. Solution-phase fragment coupling procedures for producing oligonucleotide conjugates are often tedious, produce moderate yields and reaction byproducts are frequently difficult to remove. We have developed an improved method for solid-phase coupling of ligands to oligonucleotides via disulfides directly after solid-phase synthesis. A 2'-thiol introduced using a modified nucleotide building block was orthogonally deprotected on the controlled pore glass solid support with N-butylphosphine. Oligolysine peptides and a short monodisperse ethylene glycol chain were successfully coupled to the deprotected thiol. Cleavage from the resin and full removal of oligonucleotide protection groups were achieved using methanolic ammonia. After standard desalting, and without further purification, homogenous conjugates were obtained as demonstrated by HPLC, gel electrophoresis, and mass spectrometry. The attachment of both amphiphilic and cationic ligands proves the versatility of the conjugation procedure. An antisense oligonucleotide conjugate with hexalysine showed pronounced gene silencing in a cell culture tumor model in the absence of a transfection reagent and the corresponding ethylene glycol conjugate resulted in down regulation of the target gene to nearly 50% after naked application.


Assuntos
Oligonucleotídeos/química , Técnicas de Síntese em Fase Sólida/métodos , Dissulfetos/química , Inativação Gênica/efeitos dos fármacos , Humanos , Ligantes , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/uso terapêutico , Peptídeos/química , Polietilenoglicóis/química , Polilisina/química , Células Tumorais Cultivadas
8.
Future Med Chem ; 7(13): 1657-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26381134

RESUMO

BACKGROUND: Despite recent advances, major hurdles still need to be cleared for widespread application of therapeutic antisense technologies. In particular, pharmacokinetic properties and efficient cellular uptake need to be improved through chemical derivatization or bioconjugation. RESULTS: The 2'-O-thioethylene nucleotide building block affords easy implementation into standard oligonucleotide synthesis protocols and was used to attach oligolysine chains to phosphodiester oligonucleotides by direct reaction with S-sulfonate protected peptides. Efficient gene silencing was induced in a cell culture model after transfection reagent-free application of the conjugates. CONCLUSION: A facile optimized procedure for generating oligonucleotide-peptide conjugates was established. The attachment of short basic peptides via a labile linker is sufficient to enhance membrane permeability of oligonucleotides and result in successful gene silencing.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Oligonucleotídeos/síntese química , Oligonucleotídeos/farmacocinética , Oligopeptídeos/síntese química , Oligopeptídeos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Dissulfetos/síntese química , Dissulfetos/farmacocinética , Dissulfetos/farmacologia , Inativação Gênica/efeitos dos fármacos , Humanos , Lisina/síntese química , Lisina/farmacocinética , Lisina/farmacologia , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Oligonucleotídeos/farmacologia , Oligopeptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética
9.
PLoS One ; 10(9): e0139101, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406496

RESUMO

Endothelial cells are often present at inflammation sites. This is the case of endothelial cells of the blood-brain barrier (BBB) of patients afflicted with neurodegenerative disorders such as Alzheimer's, Parkinson's, or multiple sclerosis, as well as in cases of bacterial meningitis, trauma, or tumor-associated ischemia. Inflammation is a known modulator of gene expression through the activation of transcription factors, mostly NF-κB. RLIP76 (a.k.a. RALBP1), an ATP-dependent transporter of electrophile-glutathione conjugates, modulates BBB permeability through the regulation of tight junction function, cell adhesion, and exocytosis. Genes and pathways regulated by RLIP76 are transcriptional targets of tumor necrosis factor alpha (TNF-α) pro-inflammatory molecule, suggesting that RLIP76 may also be an inflammation target. To assess the effects of TNF-α on RLIP76, we faced the problem of choosing reference genes impervious to TNF-α. Since such genes were not known in human BBB endothelial cells, we subjected these to TNF-α, and measured by quantitative RT-PCR the expression of housekeeping genes commonly used as reference genes. We find most to be modulated, and analysis of several inflammation datasets as well as a metaanalysis of more than 5000 human tissue samples encompassing more than 300 cell types and diseases show that no single housekeeping gene may be used as a reference gene. Using three different algorithms, however, we uncovered a reference geneset impervious to TNF-α, and show for the first time that RLIP76 expression is induced by TNF-α and follows the induction kinetics of inflammation markers, suggesting that inflammation can influence RLIP76 expression at the BBB. We also show that MRP1 (a.k.a. ABCC1), another electrophile-glutathione transporter, is not modulated in the same cells and conditions, indicating that RLIP76 regulation by TNF-α is not a general property of glutathione transporters. The reference geneset uncovered herein should aid in future gene expression studies in inflammatory conditions of the BBB.


Assuntos
Barreira Hematoencefálica/patologia , Células Endoteliais/metabolismo , Genes Essenciais , Glutationa/metabolismo , Inflamação/genética , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Sítios de Ligação , Biomarcadores/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Estudos de Associação Genética , Humanos , Inflamação/patologia , Camundongos , NF-kappa B/metabolismo , Regiões Promotoras Genéticas/genética , Ratos , Software , Fator de Necrose Tumoral alfa/farmacologia
10.
Int J Mol Sci ; 15(4): 6399-411, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24739811

RESUMO

Recombinant monoclonal antibodies (rmAbs) are medicinal products obtained by rDNA technology. Consequently, like other biopharmaceuticals, they require the extensive and rigorous characterization of the quality attributes, such as identity, structural integrity, purity and stability. The aim of this work was to study the suitability of gel electrophoresis for the assessment of charge heterogeneity, post-translational modifications and the stability of the therapeutic, recombinant monoclonal antibody, trastuzumab. One-dimensional, SDS-PAGE, under reducing and non-reducing conditions, and two-dimensional gel electrophoresis were used for the determination of molecular mass (Mr), the isoelectric point (pI), charge-related isoform patterns and the stability of trastuzumab, subjected to stressed degradation and long-term conditions. For the assessment of the influence of glycosylation in the charge heterogeneity pattern of trastuzumab, an enzymatic deglycosylation study has been performed using N-glycosidase F and sialidase, whereas carboxypeptidase B was used for the lysine truncation study. Experimental data documented that 1D and 2D gel electrophoresis represent fast and easy methods to evaluate the quality of biological medicinal products. Important stability parameters, such as the protein aggregation, can be assessed, as well.


Assuntos
Anticorpos Monoclonais Humanizados/análise , Anticorpos Monoclonais/análise , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Eletroforese em Gel Bidimensional/normas , Eletroforese em Gel de Poliacrilamida/normas , Glicosilação , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Peso Molecular , Isoformas de Proteínas/análise , Estabilidade Proteica , Controle de Qualidade , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Temperatura , Trastuzumab
11.
PLoS One ; 9(1): e86806, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24466249

RESUMO

The aim of this work was to conduct a comprehensive study about the transport properties of NSAIDs across the blood-brain barrier (BBB) in vitro. Transport studies with celecoxib, diclofenac, ibuprofen, meloxicam, piroxicam and tenoxicam were accomplished across Transwell models based on cell line PBMEC/C1-2, ECV304 or primary rat brain endothelial cells. Single as well as group substance studies were carried out. In group studies substance group compositions, transport medium and serum content were varied, transport inhibitors verapamil and probenecid were added. Resulted permeability coefficients were compared and normalized to internal standards diazepam and carboxyfluorescein. Transport rankings of NSAIDs across each model were obtained. Single substance studies showed similar rankings as corresponding group studies across PBMEC/C1-2 or ECV304 cell layers. Serum content, glioma conditioned medium and inhibitors probenecid and verapamil influenced resulted permeability significantly. Basic differences of transport properties of the investigated NSAIDs were similar comparing all three in vitro BBB models. Different substance combinations in the group studies and addition of probenecid and verapamil suggested that transporter proteins are involved in the transport of every tested NSAID. Results especially underlined the importance of same experimental conditions (transport medium, serum content, species origin, cell line) for proper data comparison.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Astrócitos/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Animais , Astrócitos/citologia , Transporte Biológico Ativo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Meios de Cultivo Condicionados/farmacologia , Descoberta de Drogas , Endotélio Vascular/citologia , Glioma/tratamento farmacológico , Glioma/patologia , Masculino , Ratos , Ratos Wistar , Suínos , Distribuição Tecidual
12.
ChemMedChem ; 8(1): 82-94, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23225329

RESUMO

The elongated structures of polyamine inverse agonists such as 1,12-diaminododecane (N12N) and 5-(4-aminobutyl)-2-thiopheneoctanamine (N4T8N) lend themselves to a combinatorial chemistry approach to explore a potential polyamine pharmacophore at the NMDA receptor. Herein we describe more than 100 new analogues of N4T8N obtained by breaking up the long octanamine arm into a dipeptide chain of equivalent length. Solid-phase parallel synthesis based on cross-linked polystyrene and a Wang anchor allowed the low-scale preparation of four small libraries based on the combination of two amino acid residues (out of Gly, Leu, Phe, Lys, phenylglycine, Tyr, Trp, His, and Arg). The obtained compounds were tested as modulators of [(3) H]MK-801 binding to rat brain membranes and of NMDA-induced currents in cultured rat hippocampal neurons. Compounds with two aromatic residues acted as binding inhibitors (inverse agonists). Compounds with two Lys residues acted as binding stimulators (agonists) and had stimulatory and inhibitory effects on NMDA-induced currents, depending on the holding potential. High sensitivity of binding inhibition to spermine was conferred by a Tyr residue, whereas a His residue favored high potency at acidic pH.


Assuntos
Dipeptídeos/química , Dipeptídeos/farmacologia , Poliaminas/química , Poliaminas/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ligação Proteica/efeitos dos fármacos , Ratos , Receptores de N-Metil-D-Aspartato/química , Técnicas de Síntese em Fase Sólida , Espermina/metabolismo
13.
Life (Basel) ; 3(3): 486-501, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-25369818

RESUMO

Experiments will be presented and reviewed to support the hypothesis that the intrinsic reactivity of formaldehyde may lead to the formation of a rather comprehensive set of defined biomolecules, including D-glucose, thus fostering concepts of evolution considering the existence of a premetabolic system as a primordial step in the generation of life.

14.
Sci Pharm ; 80(2): 311-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22896818

RESUMO

Capillary electrophoresis is competitive to HPLC and other chromatographic methods, predominantly when charged analytes have to be separated. The time of analysis can be reduced by the use of very short capillaries applying a high voltage. In most instruments which are commercially available the so-called 'short end' of the capillary can be used for separation, leading to very rapid separations. In this contribution we want to demonstrate this approach by using Diclofenac Sodium as an analyte.

15.
J Pharm Sci ; 101(11): 4075-99, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22911654

RESUMO

During the last century, particularly the latter half, spectacular progress has been made in improving the health and longevity of people. The reasons are many, but the development of medicines has played a critical role. This report documents and reflects on the impressive contribution that those working in the pharmaceutical sciences have made to healthcare over the past 50 years. It is divided into six sections (drug discovery; absorption, distribution, metabolism, and excretion; pharmacokinetics and pharmacodynamics; drug formulation; drug regulation; and drug utilization), each describing key contributions that have been made in the progression of medicines, from conception to use. A common thread throughout is the application of translational science to the improvement of drug discovery, development, and therapeutic application. Each section has been coordinated by a leading scientist who was asked, after consulting widely with many colleagues across the globe, to identify "The five most influential ideas/concepts/developments introduced by 'pharmaceutical scientists' (in their field) over the past 50 years?" Although one cannot predict where the important breakthroughs will come in the future to meet the unmet medical needs, the evidence presented in this report should leave no doubt that those engaged in the pharmaceutical sciences will continue to make their contributions heavily felt.


Assuntos
Química Farmacêutica/história , Descoberta de Drogas , História do Século XX , História do Século XXI , Farmacocinética , Farmacologia
16.
Sci Pharm ; 79(4): 877-83, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22145111

RESUMO

Calibration of complex analytical systems is always a difficult task. Nevertheless, a suitable approach has to be designed before the systems can be introduced into routine analysis. In literature, many methods have been described for the purpose of calibrating such systems, but only a few of them deal with capillary elctrophoresis. Here, we want to demonstrate a general approach to how the calibration of this type of analytical instrument becomes feasible.

17.
J Pharm Biomed Anal ; 56(4): 684-91, 2011 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-21813259

RESUMO

The principal objective of this study was the evaluation of two-dimensional gel electrophoresis (2-DE) in combination with MALDI-TOF MS, after tryptic digest with regard to suitability for qualitative characterization and identification of therapeutic recombinant monoclonal antibodies trastuzumab and rituximab. Moreover, the impact of post-translational modifications of these glycoproteins on the electrophoresis behavior has been evaluated. 1-D SDS-PAGE, in reducing and non-reducing conditions, and 2-DE were used for the assessment of M(r) and the monitorization of deglycosylation efficiency. In addition, 2-DE was used for the determination of pIs. 2-DE gels revealed characteristic glycoprotein migration behavior, highly complex spot pattern, typical for recombinant monoclonal antibodies. N-linked oligosaccharides were released with PNGase F; enzymatic desialination was studied with sialidase and carboxypeptidase B was used for the study of lysine truncation. Peptide spots resolved in 2-DE gels were in gel tryptically digested, resulting peptides were subjected to MALDI-TOF MS analysis and peptide mass fingerprinting (PMF) has been used for the identity confirmation of both monoclonal antibodies.


Assuntos
Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Murinos/química , Anticorpos Monoclonais/química , Antineoplásicos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais Humanizados/análise , Anticorpos Monoclonais Humanizados/metabolismo , Anticorpos Monoclonais Murinos/análise , Anticorpos Monoclonais Murinos/metabolismo , Antineoplásicos/análise , Antineoplásicos/metabolismo , Eletroforese em Gel Bidimensional/métodos , Glicoproteínas/análise , Glicoproteínas/metabolismo , Humanos , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Mapeamento de Peptídeos , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/análise , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Peptídeos/análise , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/análise , Proteínas Recombinantes/metabolismo , Rituximab , Trastuzumab
18.
Electrophoresis ; 32(12): 1438-43, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21626521

RESUMO

2-DE and MALDI-TOF MS are useful techniques for the quality evaluation of medicinal products derived from recombinant DNA technology. The principal objective of this study has been to evaluate the suitability of 2-DE in combination with MALDI-TOF MS for the quality study of the therapeutic recombinant protein, abatacept. 1-DE SDS-PAGE, under reducing and nonreducing conditions, and 2-DE analysis were used for the assessment of M(r) , pI, and enzymatic deglycosylation efficiency of abatacept. 2-DE allowed the assessment of product identity, purity, charge heterogeneity, isoform pattern, and post-translational modifications. Furthermore, optimization of the deglycosylation procedure, charge heterogeneity, and sample preparation for the subsequent MALDI-TOF MS analysis has been addressed. PMF analysis allowed rapid identity confirmation of abatacept.


Assuntos
Eletroforese em Gel Bidimensional/métodos , Imunoconjugados/química , Proteínas Recombinantes de Fusão/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Abatacepte , Sequência de Aminoácidos , Bases de Dados Factuais , Glicosilação , Imunoconjugados/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/metabolismo
19.
Brain Res ; 1394: 49-61, 2011 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21549356

RESUMO

Changes of the functionality of the blood-brain barrier (BBB) have been reported in the context of several brain related diseases such as multiple sclerosis, epilepsy, Alzheimer's disease and stroke. Several publications indicated the presence and functionality of the NMDA receptor (NMDAR) at the brain endothelium and a possible involvement of the NMDAR in the above-mentioned diseases. Recently, it was shown that the application of the NMDAR antagonist MK801 can block several adverse effects at the BBB in vitro, but also that MK801 can significantly change the proteome of brain endothelial cells without simultaneous stimulation of NMDAR by glutamate. Based on these reports we investigated if NMDAR antagonists MK801 and D-APV can affect the intracellular calcium level (Ca²âºi) of an in vitro BBB model based on human cell line ECV304 on their own and compared these results to effects mediated by NMDAR agonists glutamate and NMDA. Treatment of ECV304 cells for 30 min with glutamate resulted in no significant change of Ca²âºi. On the contrary, application of NMDA and NMDAR antagonists D-APV and MK801 led to a significant and concentration dependent decrease of Ca²âºi. Further studies revealed that glutamate was able to decrease the transendothelial electrical resistance (TEER) of the BBB in vitro model, whereas NMDA and D-APV were able to increase TEER. Analysis of the protein expression levels of tight junctional molecules ZO-1 and occludin showed a complex regulation after application of NMDAR modulators. In summary, it was shown that NMDAR antagonists can alter BBB key properties in vitro on their own. Moreover, although qPCR results confirmed the presence of NMDA receptor subunits NR1, NR2A, NR2B and NR2C, membrane binding studies failed to prove the typical plasma membrane localization and functionality in human BBB cell line ECV304.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , 2-Amino-5-fosfonovalerato/farmacologia , Barreira Hematoencefálica/metabolismo , Western Blotting , Cálcio/metabolismo , Linhagem Celular , Maleato de Dizocilpina/farmacologia , Células Endoteliais/metabolismo , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Humanos , Técnicas In Vitro , Proteínas de Membrana/metabolismo , Ocludina , Fosfoproteínas/metabolismo , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína da Zônula de Oclusão-1
20.
ChemMedChem ; 5(8): 1344-52, 2010 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-20544786

RESUMO

Phosphorothioate antisense oligonucleotides have been widely used in clinical studies for rational sequence-specific gene silencing. However, several sequence-unspecific off-target effects have been recently described for this compound class. In contrast to siRNA-mediated knockdown of the same gene, the bcl-2-targeted oblimersen (Genasense, G3139) downregulates a number of proteins involved in apoptotic resistance and several glycolytic enzymes in 607B human melanoma cells. Regardless of their target, phosphorothioate-modified antisense and siRNA compounds, but not oligonucleotides with a phosphodiester backbone, resulted in a similar impact on the proteome. Unspecifically downregulated proteins include cancer markers involved in apoptotic resistance and endoplasmatic reticulum (ER) stress such as the 78 kDa glucose regulated protein (GRP 78), protein disulfide isomerase A3 (PDIA3, GRP 58), calumenin, and galectin-1, as well as the glycolytic enzymes triose phosphate isomerase, glyceraldehyde phosphodehydrogenase, and phosphoglycerate mutase. The depletion of the glycolytic enzymes is reflected by a decrease in L-lactate production, indicating a partial reversal of the Warburg effect. Compared with other phosphorothioate oligonucleotides, oblimersen generally led to a more pronounced effect both in terms of the number of influenced proteins and the extent of downregulation, suggesting a synergistic effect of Bcl-2 downregulation.


Assuntos
Oligonucleotídeos Antissenso/química , Fosfatos/química , Tionucleotídeos/química , Apoptose , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Eletroforese em Gel Bidimensional , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lactatos/metabolismo , Melanoma/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo
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