A meta-analysis using data from 3 phase 1 studies evaluated the pharmacokinetics (PK) and pharmacodynamics (PD) of Sandoz biosimilar versus US- and EU-reference pegfilgrastim. The studies included a single-dose, double-blind, 3-arm, parallel-group study (study 1); a single-dose, double-blind, 2-way crossover study (study 2); and a single-dose, double-blind, 3-way, 6-sequence crossover study (study 3). Healthy male and female subjects were randomized to receive the proposed biosimilar (all studies), US-reference biologic (studies 1 and 3), or EU-reference biologic (studies 1, 2, and 3).
View Article and Find Full Text PDFAims: Recombinant PEGylated human granulocyte colony-stimulating factor (pegfilgrastim) is indicated for the reduction of chemotherapy-induced neutropenia and prevention of febrile neutropenia. Biosimilar pegfilgrastim is expected to reduce the financial burden of this complication of chemotherapy. The aim of this study was to demonstrate biosimilarity between Sandoz biosimilar pegfilgrastim and its US- and EU-approved reference biologics.
View Article and Find Full Text PDFThe use of banked human tissue, obtained with informed consent after elective surgical procedures, represents a powerful model for understanding underlying mechanisms of diseases or therapeutic interventions and for establishing prognostic markers. However, donated tissues typically have varying times of warm ischaemia in situ due to blood arrest or cold ischaemia due to procurement and transportation. Hence, before using these tissues, it is important to carry out pre-analytical studies to ensure that they are representative of the in vivo state.
View Article and Find Full Text PDFIsolated human primary hepatocytes are an essential in vitro model for basic and clinical research. For successful application as a model, isolated hepatocytes need to have a good viability and be available in sufficient yield. Therefore, this study aims to identify donor characteristics, intra-operative factors, tissue processing and cell isolation parameters that affect the viability and yield of human hepatocytes.
View Article and Find Full Text PDFBackground: Augmenter of Liver Regeneration (ALR), a protein synthesized in the liver is suggested to be protective against oxidative stress-induced cell death. Hepatic ischemia-reperfusion (I/R) injury is triggered by reactive oxygen species. Here, we tested the hypothesis that ALR attenuates hepatic I/R injury in vivo.
View Article and Find Full Text PDFThe liver, an organ with an exceptional regeneration capacity, carries out a wide range of functions, such as detoxification, metabolism and homeostasis. As such, hepatocytes are an important model for a large variety of research questions. In particular, the use of human hepatocytes is especially important in the fields of pharmacokinetics, toxicology, liver regeneration and translational research.
View Article and Find Full Text PDFThis review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways.
View Article and Find Full Text PDFBackground: High-quality biospecimens of human origin with annotated clinical and procedural data are an important tool for biomedical research, not only to map physiology, pathophysiology and aetiology but also to go beyond in translational research. This has opened a new special field of research known as 'biobanking', which focuses on how to collect, store and provide these specimens and data, and which is substantially supported by national and European funding.
Purpose: An overview on biobanking is given, with a closer look on a clinical setting, concerning a necessary distinction from clinical trials and studies as well as a comparison of prospective sample collection with secondary use of archived samples from diagnostics.
The accuracy of information garnered by real-time quantitative polymerase chain reaction (RT-qPCR), an important technology for elucidating molecular mechanisms of disease, is dependent on tissue quality. Thus, this study aimed to determine the effects of intra-operative manipulation, extended processing times, different temperatures or storage in RNAlater on RNA quality in liver samples for tissue banking. Liver samples, flash-frozen or in RNAlater, were collected over a time course (during surgery before blood arrest up to 1 day after surgery) with samples kept either at room temperature (RT) or on ice.
View Article and Find Full Text PDFIdentification of the signaling pathways that regulate cyclic nucleotide microdomains is essential to our understanding of cardiac physiology and pathophysiology. Although there is growing evidence that the plasma membrane Ca(2+)/calmodulin-dependent ATPase 4 (PMCA4) is a regulator of neuronal nitric-oxide synthase, the physiological consequence of this regulation is unclear. We therefore tested the hypothesis that PMCA4 has a key structural role in tethering neuronal nitric-oxide synthase to a highly compartmentalized domain in the cardiac cell membrane.
View Article and Find Full Text PDFEpstein-Barr virus (EBV; human herpesvirus 4) poses major clinical problems worldwide. Following primary infection, EBV enters a form of long-lived latency in B lymphocytes, expressing few viral genes, and it persists for the lifetime of the host with sporadic bursts of viral replication. The switch between latency and replication is governed by the action of a multifunctional viral protein Zta (also called BZLF1, ZEBRA, and Z).
View Article and Find Full Text PDFEBV (Epstein-Barr virus) alternates between latency and lytic replication. During latency, the viral genome is largely silenced by host-driven methylation of CpG motifs and in the switch to the lytic cycle this epigenetic silencing is overturned. A key event is the activation of the viral protein Zta with three ZREs (Zta-response elements) from the BRLF1 promoter (referred to as Rp).
View Article and Find Full Text PDFEpstein-Barr virus (EBV) causes infectious mononucleosis and is associated with various malignancies, including Burkitt's lymphoma and nasopharyngeal carcinoma. Like all herpesviruses, the EBV life cycle alternates between latency and lytic replication. During latency, the viral genome is largely silenced by host-driven methylation of CpG motifs and, in the switch to the lytic cycle, this epigenetic silencing is overturned.
View Article and Find Full Text PDFThe Epstein-Barr virus transcription factor Zta (encoded by BZLF1) is a bZIP protein containing an alpha-helical coiled-coil homodimerization motif (zipper). The Zta zipper forms less-stable dimers than other bZIP proteins, and an adjacent region (CT) interacts with the zipper to form a novel structure that is proposed to strengthen the dimer. Here we question the role of the CT region for Zta function.
View Article and Find Full Text PDFMany viruses, with distinct replication strategies, activate DNA-damage response pathways, including the lentivirus human immunodeficiency virus (HIV) and the DNA viruses Epstein-Barr virus (EBV), herpes simplex virus 1, adenovirus and SV40. DNA-damage response pathways involving DNA-dependent protein kinase, ataxia-telengiectasia mutated (ATM) and 'ataxia-telengiectasia and Rad3-related' (ATR) have all been implicated. This review focuses on the effects of HIV and EBV replication on DNA repair pathways.
View Article and Find Full Text PDFZta, the product of the BZLF1 gene carried by Epstein-Barr virus (EBV), is crucial for reactivation of EBV from latency. Zta is a member of the bZIP family of transcription factors, and in common with many of these, Zta possesses a conserved cysteine residue in its basic region (C189) and a further cysteine residue in its ZIP region (C222). We demonstrate that C189 is required to reactivate EBV from latency but C222 is not and that this single amino acid affects two independent functions of Zta, (i) binding to a Zta-responsive site and (ii) manipulating the cell cycle.
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