Publications by authors named "Robert K Gieseler"

Liposomal formulations of antibiotics for inhalation offer the potential for the delivery of high drug doses, controlled drug release kinetics in the lung, and an excellent safety profile. In this study, we evaluated the performance of a liposomal formulation for the poorly soluble, antituberculosis agent, bedaquiline. Bedaquiline was encapsulated within monodisperse liposomes of ∼70 nm at a relatively high drug concentration (∼3.

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The burden of chronic liver disease is globally increasing at an alarming rate. Chronic liver injury leads to liver inflammation and fibrosis (LF) as critical determinants of long-term outcomes such as cirrhosis, liver cancer, and mortality. LF is a wound-healing process characterized by excessive deposition of extracellular matrix (ECM) proteins due to the activation of hepatic stellate cells (HSCs).

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This Editorial precedes the Special Issue entitled "Novel Challenges and Therapeutic Options for Liver Diseases". Following a historical outline of the roots of hepatology, we provide a brief insight into our colleagues' contributions in this issue on the current developments in this discipline related to the prevention of liver diseases, the metabolic dysfunction-associated steatotic liver disease (or non-alcoholic fatty liver disease, respectively), liver cirrhosis, chronic viral hepatitides, acute-on-chronic liver failure, liver transplantation, the liver-microbiome axis and microbiome transplantation, and telemedicine. We further add some topics not covered by the contributions herein that will likely impact future hepatology.

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l-Ornithine- l-aspartate (LOLA) reduces toxic ammonium (NH) plasma levels in hepatic encephalopathy. NH detoxification/excretion is achieved by its incorporation into urea and glutamine via activation of carbamoyl phosphate synthetase 1 (CSP1) by l-ornithine and stimulation of arginase by l-aspartate. We aimed at identifying additional molecular targets of LOLA as a potential treatment option for non-alcoholic fatty liver disease (NAFLD).

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Aging is characterized by the progressive decline of biological integrity and its compensatory mechanisms as well as immunological dysregulation. This goes along with an increasing risk of frailty and disease. Against this background, we here specifically focus on the aging of the human liver.

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Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Importantly, NAFLD increases the risk for cardiovascular disease (CVD). A causal relationship has been substantiated.

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Background: Acute liver failure (ALF) occurs as a rare, sudden, extensive loss of liver function in a previously healthy liver. In advanced cases, ALF may require liver transplantation (LT). Available prognostic parameters have limited accuracy to decide, which patient to consider for LT.

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Nontuberculous mycobacterial infections rapidly emerge and demand potent medications to cope with resistance. In this context, targeted loco-regional delivery of aerosol medicines to the lungs is an advantage. However, sufficient antibiotic delivery requires engineered aerosols for optimized deposition.

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A transcriptome-wide analysis of human liver for demonstrating differences between young and old humans has not yet been performed. However, identifying major age-related alterations in hepatic gene expression may pinpoint ontogenetic shifts with important hepatic and systemic consequences, provide novel pharmacogenetic information, offer clues to efficiently counteract symptoms of old age, and improve the overarching understanding of individual decline. Next-generation sequencing (NGS) data analyzed by the Mann-Whitney nonparametric test and Ensemble Feature Selection (EFS) bioinformatics identified 44 transcripts among 60,617 total and 19,986 protein-encoding transcripts that significantly ( = 0.

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The role of visceral white adipose tissue (vWAT) in the progression of non-alcoholic liver disease (NAFLD) with its sub entities non-alcoholic fatty liver and steatohepatitis (NAFL; NASH) is underinvestigated. We thus explored mechanisms of fibrosis and regulated cell death in vWAT and liver tissue. In NAFLD, women displayed significantly more fibrosis in vWAT than men, and collagen 1α mRNA expression was significantly upregulated.

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In this work, a method for the preparation of the highly lipophilic labeling synthon [Zr]Zr(oxinate) was optimized for the radiolabeling of liposomes and human induced pluripotent stem cells (hiPSCs). The aim was to establish a robust and reliable labeling protocol for enabling up to one week positron emission tomography (PET) tracing of lipid-based nanomedicines and transplanted or injected cells, respectively. [Zr]Zr(oxinate) was prepared from oxine (8-hydroxyquinoline) and [Zr]Zr(OH)(CO).

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Pulmonary delivery of nanocarriers for novel antimycobacterial compounds is challenging because the aerodynamic properties of nanomaterials are sub-optimal for such purposes. Here, we report the development of dry powder formulations for nanocarriers containing benzothiazinone 043 (BTZ) or levofloxacin (LVX), respectively. The intricacy is to generate dry powder aerosols with adequate aerodynamic properties while maintaining both nanostructural integrity and compound activity until reaching the deeper lung compartments.

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Reliable test systems to identify hepatotoxicity are essential to predict unexpected drug-related liver injury. Here we present a human ex-vivo liver model to investigate acetaminophen-induced liver injury. Human liver tissue was perfused over a 30 hour period with hourly sampling from the perfusate for measurement of general metabolism and clinical parameters.

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Introduction: Changes in thyroid hormone levels, mostly as non-thyroidal illness syndrome (NTIS), have been described in many diseases. However, the relationship between acute liver failure (ALF) and thyroid hormone levels has not yet been clarified. The present study evaluates potential correlations of select thyroid functional parameters with ALF.

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Targeted drug delivery systems hold promise for selective provision of active compounds to distinct tissues or cell subsets. Thus, locally enhanced drug concentrations are obtained that would confer improved efficacy. As a consequence adverse effects should be diminished, as innocent bystander cells are less affected.

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Objective: Non-alcoholic fatty liver disease (NAFLD) is closely linked to obesity and constitutes part of the metabolic syndrome, which have been associated with low serum vitamin D (VD). Due to known crosstalk between VD and transforming growth factor (TGF)-β signalling, VD has been proposed as an antifibrotic treatment.

Design: We evaluated the association between VD, the vitamin D receptor (VDR) and liver fibrosis in primary human hepatic stellate cells (phHSC) and 106 morbidly obese patients with NAFLD.

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Liver transplantation in cirrhotic patients is accompanied by severe bleeding. Indeed, the first 100 recipients of liver allografts transplanted by Thomas E. Starzl died mainly by uncontrolled bleeding.

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Various models are used for investigating human liver diseases and testing new drugs. However, data generated in such models have only limited relevance for in vivo conditions in humans. We present here an ex vivo perfusion system using human liver samples that enables the characterization of parameters in a functionally intact tissue context.

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Unlabelled: Acute liver failure (ALF) is associated with massive short-term cell death, whereas chronic liver injury is accompanied by continuous cell death. Hepatic stellate cells (HSCs) contribute to tissue repair and liver fibrosis in chronic liver injury, although their role in ALF remains unexplained. Twenty-nine patients (median age = 43 years, 17 females and 12 males) with ALF according to the Acute Liver Failure Study Group criteria were included.

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Background & Aims: Predicting the probability of patients with acute liver failure (ALF) to recover spontaneously is of major clinical importance. As apoptotic and necrotic cell death are crucial in the pathogenesis of ALF, we determined whether selected cell-death markers predict outcome of patients with ALF and/or discriminate between etiologies.

Methods: In a prospective study (11/2006-06/2009), 68 ALF patients were recruited consecutively.

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Background & Aims: Hepatocyte apoptosis is a key event in non-alcoholic steatohepatitis (NASH). We studied the effect of obesity on free fatty acid (FFA) levels, fatty acid transport proteins (FATPs) and on extrinsic and intrinsic activation of apoptosis in the liver.

Methods: Liver biopsies were harvested from 52 morbidly obese patients [body mass index (BMI): 53.

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Unlabelled: Stress-induced soluble major histocompatibility complex class I-related chains A/B (MIC A/B) are increased in chronic liver diseases and hepatocellular malignancy. We investigated the impact of these molecules on liver injury, apoptosis, and fibrosis in nonalcoholic steatohepatitis (NASH). Blood and liver tissue were obtained from 40 patients with NASH undergoing bariatric surgery for obesity.

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Background: Acute hepatitis B virus (HBV) infection is followed by high viral replication rates leading to hepatocyte death and ultimately, in some cases, to acute liver failure (ALF) necessitating liver transplantation. Thus, the objective of treating HBV-induced ALF is to eliminate or significantly suppress HBV replication.

Methods/results: This prospective study (02/2008-02/2009) included 6 patients (1 female and 5 males, median age 35.

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Aim: To ascertain whether resveratrol affects the expression of free fatty acids (FFA)-induced profibrogenic genes, death receptors, and/or apoptosis-related molecules in human hepatic stellate cells, using the LX-2 cell line.

Methods: Cells were cultured in the presence of FFAs (2:1 oleate : palmitate) and subsequently treated with resveratrol. Gene expression rates were determined by quantitative real-time PCR.

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Background/aims: Steatosis may trigger hepatocytes to up-regulate CD95/Fas thereby increasing susceptibility to apoptosis, inflammation and fibrosis. We investigated this concept and potential roles of adiponectin and its receptors (AdipoR1; AdipoR2) in chronically HCV-infected patients.

Methods: In 98 HCV+ patients and 20 controls, sera were tested for HCV genotypes, FFAs, adiponectin and the M30 apoptosis indicator, and biopsies were evaluated for steatosis/inflammation/fibrosis, CD95/Fas (mRNA/protein), adiponectin (mRNA/protein), AdipoR1/-R2 (mRNA) and M30 (protein).

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