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1.
Clin Pharmacol Drug Dev ; 13(6): 655-664, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38651245

RESUMO

Zinpentraxin alfa is a recombinant form of the human pentraxin-2 that was studied in idiopathic pulmonary fibrosis (IPF). To improve the purity and yield of the drug material, a 2nd-generation drug product was developed. To characterize and compare the pharmacokinetic (PK) properties of the 1st- and 2nd-generation zinpentraxin alfa, PK studies were conducted in healthy volunteers (HVs). In a phase 1 randomized, double-blind, 2-sequence crossover, sequential 2-stage study (ISRCTN59409907), single intravenous (IV) doses of 1st- and 2nd-generation zinpentraxin alfa at 10 mg/kg were studied with a blinded interim analysis (IA) at the end of stage 1. Bioequivalence (BE) was achieved for the maximum observed plasma concentration (Cmax), but the overall exposure was higher for the 2nd- compared to the 1st-generation zinpentraxin alfa. The study was stopped after stage 1 as the gating criteria were met based on the result of the blinded IA. Safety profiles were similar for the 1st- and 2nd-generation drug products, and antidrug antibody (ADA) was not observed in this study.


Assuntos
Estudos Cross-Over , Voluntários Saudáveis , Componente Amiloide P Sérico , Equivalência Terapêutica , Humanos , Masculino , Método Duplo-Cego , Adulto , Componente Amiloide P Sérico/metabolismo , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Área Sob a Curva , Proteína C-Reativa/metabolismo , Proteína C-Reativa/análise , Administração Intravenosa
2.
Anal Chem ; 95(4): 2203-2212, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36669833

RESUMO

Antibody combination therapies have become viable therapeutic treatment options for certain severe diseases such as cancer. The co-formulation production approach is intrinsically associated with more complex drug product variant profiles and creates more challenges for analytical control of drug product quality. In addition to various individual quality attributes, those arising from the interactions between the antibodies also potentially emerge through co-formulation. In this study, we describe the development of a widely applicable multi-dimensional liquid chromatography coupled to tandem mass spectrometry method for antibody homo- versus hetero-aggregate characterization. The co-formulation of trastuzumab and pertuzumab was used, a challenging model system, comprising two monoclonal antibodies with very similar physicochemical properties. The data presented demonstrate the high stability of the co-formulation, where only minor aggregate formation is observed upon product storage and accelerated temperature or light-stress conditions. The results also show that the homo- and hetero-aggregates, formed in low and comparable proportions, are only marginally impacted by the formulation and product storage conditions. No preferential formation of hetero-aggregates, in comparison to the already existing pertuzumab and trastuzumab homo-aggregates, was observed.


Assuntos
Anticorpos Monoclonais , Espectrometria de Massas em Tandem , Cromatografia Líquida , Anticorpos Monoclonais/química , Trastuzumab/química
3.
Talanta ; 234: 122628, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364437

RESUMO

An international study was conducted to evaluate the performance and reliability of an online multi-dimensional (mD)-LC-MS/MS approach for the characterization of antibody charge variants. The characterization of antibody charge variants is traditionally performed by time-consuming, offline isolation of charge variant fractions by ion exchange chromatography (IEC) that are subsequently subjected individually to LC-MS/MS peptide mapping. This newly developed mD-LC-MS/MS approach enables automated and rapid characterization of charge variants using much lower sample requirements. This online workflow includes sample reduction, digestion, peptide mapping, and subsequent mass spectrometric analysis within a single, fully-automated procedure. The benefits of using online mD-LC-MS/MS for variant characterization include fewer handling steps, a more than 10-fold reduction in required sample amount, reduced sample hold time as well as a shortening of the overall turnaround time from weeks to few days compared to standard offline procedures. In this site-to-site comparison study, we evaluated the online peptide mapping data collected from charge variants of trastuzumab (Herceptin®) across three international laboratories. The purpose of this study was to compare the overall performance of the online mD-LC-MS/MS approach for antibody charge variant characterization, with all participating sites employing different mD-LC-MS/MS setups (e.g., instrument vendors, modules, columns, CDS software). The high sequence coverage (95%-97%) obtained in each laboratory, enabled a reproducible generation of tryptic peptides and the comparison of values of the charge variants. Results obtained at all three participating sites were in good agreement, highlighting the reliability and performance of this approach, and correspond with data gained by the standard offline procedure. Overall, our results underscore of the benefit mD-LC-MS/MS technology for therapeutic antibody characterization, confirming its potential to become an important tool in the toolbox of protein characterization scientists.


Assuntos
Laboratórios , Espectrometria de Massas em Tandem , Anticorpos Monoclonais , Cromatografia Líquida , Humanos , Reprodutibilidade dos Testes
5.
Int J Pediatr Endocrinol ; 2013(1): 21, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24344648

RESUMO

BACKGROUND: Morbidity and mortality in T1DM depend on metabolic control, which is assessed by HbA1c measurements every 3-4 months. Patients' self-perception of glycemic control depends on daily blood glucose monitoring. Little is known about the congruence of patients' and professionals' perception of metabolic control in T1DM. OBJECTIVE: To assess the actual patients' self-perception and objective assessment (HbA1c) of metabolic control in T1DM children and adolescents and to investigate the possible factors involved in any difference. METHODS: Patients with T1DM aged 8 - 18 years were recruited in a cross-sectional, retrospective and prospective cohort study. Data collection consisted of clinical details, measured HbA1c, self-monitored blood glucose values and questionnaires assessing self and professionals' judgment of metabolic control. RESULTS: 91 patients participated. Mean HbA1c was 8.03%. HbA1c was higher in patients with a diabetes duration > 2 years (p = 0.025) and in patients of lower socioeconomic level (p = 0.032). No significant correlation was found for self-perception of metabolic control in well and poorly controlled patients. We found a trend towards false-positive memory of the last HbA1c in patients with a HbA1c > 8.5% (p = 0.069) but no difference in patients' knowledge on target HbA1c between well and poorly controlled patients. CONCLUSIONS: T1DM patients are aware of a target HbA1c representing good metabolic control. Ill controlled patients appear to have a poorer recollection of their HbA1c. Self-perception of actual metabolic control is similar in well and poorly controlled T1DM children and adolescents. Therefore, professionals should pay special attention that ill controlled T1DM patients perceive their HbA1c correctly.

6.
J Am Chem Soc ; 135(31): 11670-7, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23837603

RESUMO

Rapid evolution of enzymes provides unique molecular insights into the remarkable adaptability of proteins and helps to elucidate the relationship between amino acid sequence, structure, and function. We interrogated the evolution of the phosphotriesterase from Pseudomonas diminuta (PdPTE), which hydrolyzes synthetic organophosphates with remarkable catalytic efficiency. PTE is thought to be an evolutionarily "young" enzyme, and it has been postulated that it has evolved from members of the phosphotriesterase-like lactonase (PLL) family that show promiscuous organophosphate-degrading activity. Starting from a weakly promiscuous PLL scaffold (Dr0930 from Deinococcus radiodurans ), we designed an extremely efficient organophosphate hydrolase (OPH) with broad substrate specificity using rational and random mutagenesis in combination with in vitro activity screening. The OPH activity for seven organophosphate substrates was simultaneously enhanced by up to 5 orders of magnitude, achieving absolute values of catalytic efficiencies up to 10(6) M(-1) s(-1). Structural and computational analyses identified the molecular basis for the enhanced OPH activity of the engineered PLL variants and demonstrated that OPH catalysis in PdPTE and the engineered PLL differ significantly in the mode of substrate binding.


Assuntos
Organofosfatos/metabolismo , Hidrolases de Triester Fosfórico/genética , Hidrolases de Triester Fosfórico/metabolismo , Pseudomonas/enzimologia , Pseudomonas/metabolismo , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Cristalografia por Raios X , Hidrólise , Modelos Moleculares , Mutagênese , Hidrolases de Triester Fosfórico/química , Conformação Proteica , Pseudomonas/química , Pseudomonas/genética , Estereoisomerismo , Especificidade por Substrato
7.
Clin Endocrinol (Oxf) ; 76(5): 683-90, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22026507

RESUMO

OBJECTIVE: A number of mathematical models for predicting growth and final height outcome have been proposed to enable the clinician to 'individualize' growth-promoting treatment. However, despite optimizing these models, many patients with isolated growth hormone deficiency (IGHD) do not reach their target height. The aim of this study was to analyse the impact of polymorphic genotypes [CA repeat promoter polymorphism of insulin-like growth factor-I (IGF-I) and the -202 A/C promoter polymorphism of IGF-Binding Protein-3 (IGFBP-3)] on variable growth factors as well as final height in severe IGHD following GH treatment. DESIGN, PATIENTS AND CONTROLS: One hundred seventy eight (IGF-I) and 167 (IGFBP-3) subjects with severe growth retardation because of IGHD were studied. In addition, the various genotypes were also studied in a healthy control group of 211 subjects. RESULTS: The frequency of the individual IGF-I (CA)(n) repeats ranging from 10 to 24, with the most frequent allele containing CA(19), was similar in controls and in IGHD subjects. However, in controls, the pooled CA(19) and CA(20) as well as -202 A IGFBP-3 alleles were significantly (P < 0·01 and P < 0·001) more common in the taller [≥2 to 0 standard deviation score (SDS)] when compared with the shorter subgroup (<0 to ≤-2 SDS). Overall, the effect of recombinant human growth hormone (rhGH) replacement did not reveal any difference between the various genotypes in terms of final height. Independent of their genotype, all subjects showed a slightly lower adult height SDS compared with midparental height SDS. CONCLUSION: Our results indicate that in patients with severe IGHD, although the various IGF-I and IGFBP-3 genotypes may play a role in GH responsiveness, there was no effect on final height.


Assuntos
Repetições de Dinucleotídeos/genética , Hormônio do Crescimento Humano/deficiência , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Adulto , Idoso , Estatura/efeitos dos fármacos , Estatura/genética , Criança , Pré-Escolar , Feminino , Frequência do Gene , Genótipo , Transtornos do Crescimento/sangue , Transtornos do Crescimento/genética , Transtornos do Crescimento/metabolismo , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fenótipo , Resultado do Tratamento , Adulto Jovem
8.
Biochemistry ; 48(10): 2237-47, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19159332

RESUMO

Dr0930, a member of the amidohydrolase superfamily in Deinococcus radiodurans, was cloned, expressed, and purified to homogeneity. The enzyme crystallized in the space group P3121, and the structure was determined to a resolution of 2.1 A. The protein folds as a (beta/alpha)7beta-barrel, and a binuclear metal center is found at the C-terminal end of the beta-barrel. The purified protein contains a mixture of zinc and iron and is intensely purple at high concentrations. The purple color was determined to be due to a charge transfer complex between iron in the beta-metal position and Tyr-97. Mutation of Tyr-97 to phenylalanine or complexation of the metal center with manganese abolished the absorbance in the visible region of the spectrum. Computational docking was used to predict potential substrates for this previously unannotated protein. The enzyme was found to catalyze the hydrolysis of delta- and gamma-lactones with an alkyl substitution at the carbon adjacent to the ring oxygen. The best substrate was delta-nonanoic lactone with a kcat/Km of 1.6 x 10(6) M-1 s-1. Dr0930 was also found to catalyze the very slow hydrolysis of paraoxon with values of kcat and kcat/Km of 0.07 min-1 and 0.8 M-1 s-1, respectively. The amino acid sequence identity to the phosphotriesterase (PTE) from Pseudomonas diminuta is 30%. The eight substrate specificity loops were transplanted from PTE to Dr0930, but no phosphotriesterase activity could be detected in the chimeric PTE-Dr0930 hybrid. Mutation of Phe-26 and Cys-72 in Dr0930 to residues found in the active site of PTE enhanced the kinetic constants for the hydrolysis of paraoxon. The F26G/C72I mutant catalyzed the hydrolysis of paraoxon with a kcat of 1.14 min-1, an increase of 16-fold over the wild-type enzyme. These results support previous proposals that phosphotriesterase activity evolved from an ancestral parent enzyme possessing lactonase activity.


Assuntos
Amidoidrolases/química , Amidoidrolases/metabolismo , Deinococcus/enzimologia , Hidrolases de Triester Fosfórico/química , Hidrolases de Triester Fosfórico/metabolismo , Amidoidrolases/genética , Sequência de Aminoácidos , Substituição de Aminoácidos/fisiologia , Biocatálise , Domínio Catalítico , Cristalografia por Raios X , Deinococcus/genética , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Lactonas/química , Metais Pesados/química , Modelos Moleculares , Dados de Sequência Molecular , Hidrolases de Triester Fosfórico/genética , Conformação Proteica , Multimerização Proteica , Pseudomonas/enzimologia , Pseudomonas/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrofotometria , Eletricidade Estática , Homologia Estrutural de Proteína , Especificidade por Substrato
9.
Med Ges Gesch Beih ; 29: 167-83, 263, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18354991

RESUMO

The German writerJean Paul (Johann Paul Friedrich Richter, 1763-1825) and his friendJohann Bernhard Hermann (1761-1790) became acquainted with the thoughts of late Enlightenment at the University of Leipzig. They particularly appreciated the anthropology of Ernst Platner, who taught philosophy and aesthetics as well as medicine. Their confidential correspondence contains reflections on their respective situation and well being. Both write about feeling ill and label their illness "hypochondria". In the course of the correspondence Jean Paul's understanding of hypochondria evolves from an illness of the entrails as he follows Hermann, who supports the modern concept of hypochondria as an illness of the nerves. Two important themes from this correspondence recur in Jean Paul's novels and tales: firstly, his way of expressing comfort is related to his aesthetics, and secondly, the satirical way of portraying at least certain aspects of illness as imaginary reappears in his first successful novel "The Invisible Lodge" (1793).


Assuntos
Correspondência como Assunto/história , Pessoas Famosas , Hipocondríase/história , Literatura Moderna/história , Medicina na Literatura , Alemanha , História do Século XVIII , Humanos , Masculino , Tuberculose Pulmonar/história
11.
Swiss Med Wkly ; 134(9-10): 132-5, 2004 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-15106023

RESUMO

Critics maintain that family physicians produce radiographic images of poorer technical quality than radiologists but the impact of lower quality images on patient care is unknown. Two radiologists assessed occipitomental radiographs made in either a general practice or a certified laboratory for 247 patients with clinically diagnosed acute bacterial rhinosinusitis. With an occipitomental radiograph correct positioning is more difficult than with the usual radiographs of chest or extremities commonly made in general practice. Good positioning was less common in radiographs from general practices, with the pyramid projected below the maxillary sinuses in 63% of radiographs from general practice and 79% of radiographs from a certified laboratory. However, a radiographic diagnosis of possible acute maxillary sinusitis was as common in radiographs from general practice (38%) as in radiographs from a certified laboratory (41%). Although routine use is not recommended, family physicians with suitable technical and interpretative skills can use an occipitomental radiograph to rule out acute maxillary sinusitis in difficult cases. With a radiograph that is hard to read the physician should act as if the disease is present or refer the radiograph to a consulting radiologist.


Assuntos
Infecções Bacterianas/diagnóstico por imagem , Medicina de Família e Comunidade , Osso Occipital/diagnóstico por imagem , Qualidade da Assistência à Saúde , Rinite/diagnóstico por imagem , Sinusite/diagnóstico por imagem , Doença Aguda , Humanos , Valor Preditivo dos Testes , Radiografia , Reprodutibilidade dos Testes
12.
Rheumatol Int ; 22(1): 38-40, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12120910

RESUMO

We present the case of a patient with long-standing rheumatoid arthritis and an acute onset of total dysfunction of the posterior tibial tendon. On MRI, a rupture of the tendon was apparent. Intraoperatively, however, massive tenosynovitis with stricture of the tendon was identified as the cause of posterior tibial tendon dysfunction. This case illustrates a pitfall in MRI imaging with potential diagnostic and therapeutic consequences.


Assuntos
Artrite Reumatoide/complicações , Artrite Reumatoide/patologia , Perna (Membro)/patologia , Músculo Esquelético/patologia , Disfunção do Tendão Tibial Posterior/etiologia , Disfunção do Tendão Tibial Posterior/patologia , Tendões/patologia , Artralgia/etiologia , Artralgia/patologia , Artralgia/fisiopatologia , Artrite Reumatoide/fisiopatologia , Feminino , Humanos , Perna (Membro)/fisiopatologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Procedimentos Ortopédicos , Disfunção do Tendão Tibial Posterior/fisiopatologia , Tendões/fisiopatologia , Tenossinovite/etiologia , Tenossinovite/patologia , Tenossinovite/fisiopatologia , Resultado do Tratamento
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