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1.
BMC Nurs ; 23(1): 201, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38528537

RESUMO

BACKGROUND: Staffing ratios in nursing homes vary among the federal states of Germany, but there are no rational grounds for these variations. In a previous study, a new instrument for the standardized calculation of staffing requirements in nursing homes was developed (Algorithm 1.0). The development was based on a new empirical data collection method that derives actual and target values for the time and number of care interventions provided. Algorithm 1.0 found an increased requirement of 36% of staff in German nursing homes. Based on these results, the German legislature has commissioned a model program to trial and evaluate a complex intervention comprising increased staffing combined with strategies for organizational development. METHODS: The mixed-methods study consists of (i) developing a concept for restructuring the work organization, (ii) the application of this concept combined with increased staffing in 10 nursing homes (complex intervention), and the further development of the concept using a participatory and iterative formal evaluation process. The intervention consists of (a) quantitative measures of increased staffing based on a calculation using Algorithm 1.0 and (b) qualitative measures regarding organizational development. The intervention will be conducted over one year. The effects of the intervention on job satisfaction and quality of care will be evaluated in (iii) a comprehensive prospective, controlled summative evaluation. The results will be compared with ten matched nursing homes as a control group. Finally, (iv) prototypical concepts for qualification-oriented work organization, a strategy for the national rollout, and the further development of Algorithm 1.0 into Algorithm 2.0 will be derived. DISCUSSION: In Germany, there is an ongoing dynamic legislation process regarding further developing the long-term care sector. The study, which is the subject of the study protocol presented here, generates an evidence-based strategy for the staffing requirements for nursing homes. ETHICS AND DISSEMINATION: This study was approved by the Ethics Committee of the German Association of Nursing Science (Deutsche Gesellschaft für Pflegewissenschaft) on 02.08.2023 (amended on 20.09.2023). Research findings are disseminated through presentations at national and international conferences and publications in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: German Clinical Trails Register DRKS00031773 (Date of registration 09.11.2023).

2.
Biotechnol J ; 14(4)2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30367549

RESUMO

The availability of nucleotide sugars is considered as bottleneck for Leloir-glycosyltransferases mediated glycan synthesis. A breakthrough for the synthesis of nucleotide sugars is the development of salvage pathway like enzyme cascades with high product yields from affordable monosaccharide substrates. In this regard, the authors aim at high enzyme productivities of these cascades by a repetitive batch approach. The authors report here for the first time that the exceptional high enzyme cascade stability facilitates the synthesis of Uridine-5'-diphospho-α-d-galactose (UDP-Gal), Uridine-5'-diphospho-N-acetylglucosamine (UDP-GlcNAc), and Uridine-5'-diphospho-N-acetylgalactosamine (UDP-GalNAc) in a multi-gram scale by repetitive batch mode. The authors obtained 12.8 g UDP-Gal through a high mass based total turnover number (TTNmass ) of 494 [gproduct /genzyme ] and space-time-yield (STY) of 10.7 [g/L*h]. Synthesis of UDP-GlcNAc in repetitive batch mode gave 11.9 g product with a TTNmass of 522 [gproduct /genzyme ] and a STY of 9.9 [g/L*h]. Furthermore, the scale-up to a 200 mL scale using a pressure operated concentrator was demonstrated for a UDP-GalNAc producing enzyme cascade resulting in an exceptional high STY of 19.4 [g/L*h] and 23.3 g product. In conclusion, the authors demonstrate that repetitive batch mode is a versatile strategy for the multi-gram scale synthesis of nucleotide sugars by stable enzyme cascades.


Assuntos
Polissacarídeos/química , Uridina Difosfato Galactose/biossíntese , Uridina Difosfato N-Acetilglicosamina/biossíntese , Açúcares de Uridina Difosfato/biossíntese , Glicosiltransferases/química , Nucleotídeos/biossíntese , Nucleotídeos/química , Transferases (Outros Grupos de Fosfato Substituídos)/química , Uridina Difosfato Galactose/química , Uridina Difosfato N-Acetilglicosamina/química , Açúcares de Uridina Difosfato/química
3.
Microb Cell Fact ; 17(1): 168, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367634

RESUMO

BACKGROUND: Increasing efforts have been made to assess the potential of Escherichia coli strains for the production of complex recombinant proteins. Since a considerable part of therapeutic proteins are glycoproteins, the lack of the post-translational attachment of sugar moieties in standard E. coli expression strains represents a major caveat, thus limiting the use of E. coli based cell factories. The establishment of an E. coli expression system capable of protein glycosylation could potentially facilitate the production of therapeutics with a putative concomitant reduction of production costs. RESULTS: The previously established E. coli strain expressing the soluble form of the functional human-derived glycosyltransferase polypeptide N-acetylgalactosaminyltransferase 2 (GalNAc-T2) was further modified by co-expressing the UDP-GlcNAc 4-epimerase WbgU derived from Plesiomonas shigelloides. This enables the conversion of uridine 5'-diphospho-N-acetylglucosamine (UDP-GlcNAc) to the sugar donor uridine 5'-diphospho-N-acetylgalactosamine (UDP-GalNAc) in the bacterial cytoplasm. Initially, the codon-optimised gene wbgU was inserted into a pET-derived vector and a Tobacco Etch Virus (TEV) protease cleavable polyhistidine-tag was translationally fused to the C- terminus of the amino acid sequence. The 4-epimerase was subsequently expressed and purified. Following the removal of the polyhistidine-tag, WbgU was analysed by circular dichroism spectroscopy to determine folding state and thermal transitions of the protein. The in vitro activity of WbgU was validated by employing a modified glycosyltransferase assay. The conversion of UDP-GlcNAc to UDP-GalNAc was shown by capillary electrophoresis analysis. Using a previously established chaperone pre-/co- expression platform, the in vivo activity of both glycosyltransferase GalNAc-T2 and 4-epimerase WbgU was assessed in E. coli, in combination with a mucin 10-derived target protein. Monitoring glycosylation by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS), the results clearly indicated the in vivo glycosylation of the mucin-derived acceptor peptide. CONCLUSION: In the present work, the previously established E. coli- based expression system was further optimized and the potential for in vivo O-glycosylation was shown by demonstrating the transfer of sugar moieties to a mucin-derived acceptor protein. The results offer the possibility to assess the practical use of the described expression platform for in vivo glycosylations of important biopharmaceutical compounds in E. coli.


Assuntos
Escherichia coli/metabolismo , Mucinas/metabolismo , Sequência de Aminoácidos , Carboidratos Epimerases/isolamento & purificação , Carboidratos Epimerases/metabolismo , Dicroísmo Circular , Glicosilação , Mucinas/química , N-Acetilgalactosaminiltransferases/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
4.
J Biotechnol ; 258: 51-55, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28347767

RESUMO

The broad substrate spectrum of UDP-sugar pyrophosphorylases from plant salvage pathways is of high interest for the synthesis of expensive nucleotide sugars by straightforward enzyme cascade reactions in combination with monosaccharide kinases. We here present a new UDP-sugar pyrophosphorylase from Hordeum vulgare with favorable biochemical properties like broad pH and temperature tolerances as well as a broad substrate spectrum and high synthesis stability. Enzyme properties were determined and reaction conditions were optimized by high-through-put multiplexed capillary electrophoresis analysis. In combination with a galactokinase UDP-α-d-galactose (UDP-Gal) was efficiently synthesized with a space-time-yield of 17g/L*h for full conversion of 10mM substrate within 20min by 1.2U of each enzyme.


Assuntos
Hordeum/enzimologia , Nucleotidiltransferases/química , Nucleotidiltransferases/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Difosfato de Uridina/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Escherichia coli/genética , Hordeum/genética , Concentração de Íons de Hidrogênio , Cinética , Nucleotidiltransferases/genética , Proteínas de Plantas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Temperatura
5.
Biotechnol J ; 11(10): 1298-1308, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27311566

RESUMO

Nucleotide sugars are considered as bottleneck and expensive substrates for enzymatic glycan synthesis using Leloir-glycosyltransferases. Synthesis from cheap substrates such as monosaccharides is accomplished by multi-enzyme cascade reactions. Optimization of product yields in such enzyme modules is dependent on the interplay of multiple parameters of the individual enzymes and governed by a considerable time effort when convential analytic methods like capillary electrophoresis (CE) or HPLC are applied. We here demonstrate for the first time multiplexed CE (MP-CE) as fast analytical tool for the optimization of nucleotide sugar synthesis with multi-enzyme cascade reactions. We introduce a universal separation method for nucleotides and nucleotide sugars enabling us to analyze the composition of six different enzyme modules in a high-throughput format. Optimization of parameters (T, pH, inhibitors, kinetics, cofactors and enzyme amount) employing MP-CE analysis is demonstrated for enzyme modules for the synthesis of UDP-α-D-glucuronic acid (UDP-GlcA) and UDP-α-D-galactose (UDP-Gal). In this way we achieve high space-time-yields: 1.8 g/L⋆h for UDP-GlcA and 17 g/L⋆h for UDP-Gal. The presented MP-CE methodology has the impact to be used as general analytical tool for fast optimization of multi-enzyme cascade reactions.


Assuntos
Eletroforese Capilar/métodos , Enzimas/metabolismo , Açúcares de Nucleosídeo Difosfato/isolamento & purificação , Nucleotídeos/análise , Ensaios de Triagem em Larga Escala/métodos , Cinética , Açúcares de Nucleosídeo Difosfato/análise , Açúcares de Nucleosídeo Difosfato/biossíntese
6.
J Neural Transm (Vienna) ; 115(8): 1141-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18446261

RESUMO

Dysfunction of proteasomal protein degradation is involved in neurodegeneration in Parkinson's disease (PD). Recently we identified the regulatory proteasomal subunit S6 ATPase as a novel interactor of synphilin-1, which is a substrate of the ubiquitin-ligase Parkin (PARK2) and an interacting protein of alpha-synuclein (PARK1). To further investigate a potential role in the pathogenesis of PD, we performed a detailed mutation analysis of the S6 ATPase gene in a large sample of 486 German sporadic and familial PD patients. Direct sequencing revealed two novel intronic variants. An insertion/deletion variant in intron 5 of the S6 ATPase gene was more frequent in patients compared to controls. Moreover, this variant was significantly more frequent in early-onset compared to late-onset PD patients. The identification of a genetic link between a regulatory proteasomal subunit and PD further underscores the relevance of disturbed protein degradation in PD.


Assuntos
Adenosina Trifosfatases/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Complexo de Endopeptidases do Proteassoma/genética , ATPases Associadas a Diversas Atividades Celulares , Idoso , Alelos , Proteínas de Transporte/genética , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA , DNA Complementar/biossíntese , DNA Complementar/genética , Feminino , Genótipo , Alemanha/epidemiologia , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Polimorfismo de Fragmento de Restrição , Desnaturação Proteica , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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