Factors associated with nonadherence to medication in kidney transplant recipients.

Nonadherence in kidney transplant recipients was evaluated in this report using a questionnaire with five binary questions and one question on a continuous scale. Study participants at the University of Utah Transplant Program (n = 199) were 43.0 ± 14.2 years old; 67% were males, and 81% were White. Two questions that produced heterogeneous outcome were analyzed: 'Do you ever forget to take your medication?' (79% no, 21% yes) and 'Have you ever taken your medications late?' (67% no, 33% yes). Responses to these questions correlated (χ² 65.2, p < 0.001; correlation coefficient 0.57, p < 0.001). We performed a logistic regression analysis to identify factors associated with the combined outcome of forgetting/not taking medications altogether or taking medications off schedule. Higher comorbidity index [odds ratio (OR) 2.19, p < 0.001], living (compared to deceased) donor (OR 2.81, p = 0.005) and full-time employment were associated with forgetting medications or taking them late (OR 3.12, p = 0.01). Recipient age tended to be associated with lower risk of nonadherence, but did not reach statistical significance (OR 0.98 per year of age, p = 0.13). Education level, smoking status, recipient race, dialysis modality, number of medications and the time since first kidney transplantation were not associated with the outcome. In conclusion, renal transplant recipients with greater comorbidity, receiving kidney from a living donor and with full-time employment reported lower levels of medication adherence.

Efficacy and Tolerability of Eravacycline in Bacteremic Patients with Complicated Intra-Abdominal Infection: A Pooled Analysis from the IGNITE1 and IGNITE4 Studies.

Background: Eravacycline is a novel, fully synthetic fluorocycline antibiotic that was evaluated for the treatment of complicated intra-abdominal infections (cIAI) in two phase 3 clinical trials. The objective of this analysis was to evaluate the clinical cure and microbiologic response at the test-of-cure (TOC) visit and the safety of eravacycline in patients with cIAI and baseline bacteremia who received eravacycline versus comparators. Patients and Methods: Pooled data of patients with bacteremia from the Investigating Gram-Negative Infections Treated with Eravacycline (IGNITE) 1 and IGNITE4 studies were analyzed. All patients were randomly assigned in a one-to-one ratio to receive eravacycline 1 mg/kg intravenously every 12 hours, ertapenem 1 g intravensouly every 24 hours (IGNITE1), or meropenem 1 g intravenously every eight hours (IGNITE4) for four to 14 days. Blood and intra-abdominal samples were collected from all patients at baseline. Clinical outcome and microbiologic eradiation at the TOC visit (28 days after randomization) and safety in the microbiologic-intent-to-treat population (micro-ITT) were assessed. Results: Of 415 patients treated with eravacycline and 431 treated with carbapenem comparators, concurrent bacteremia was identified in 32 (7.7%) and 31 (7.2%) patients, respectively. Demographic and baseline characteristics were similar among treatment groups. In the micro-ITT population, the pooled clinical response at the TOC visit for eravacycline was 28 of 32 (87.5%) and was 24 of 31 (77.0%) for comparators among the subgroup with baseline bacteremia (treatment difference 5.9; 95% confidence interval [CI], -6.5 to 17.4). At TOC, microbiologic eradication of pathogens isolated from blood specimens occurred for 34 of 35 (97.1%) pathogens with eravacycline and 35 of 36 (97.2%) pathogens with comparators. The incidence of adverse events was comparable between treated groups and similar to that observed in the non-bacteremic population. Conclusion: Eravacycline demonstrated a similar clinical outcome and microbiologic eradication rate as comparator carbapenems in patients with cIAI and associated secondary bacteremia. Future clinical trials of cIAI should report outcomes of this important clinical cohort (cIAI with concurrent bacteremia) given their high risk for adverse outcomes.

Effect of matrine on primary human hepatocytes in vitro.

Matrine is a bioactive component of the traditional Chinese medical herb Sophora flavescens that has been used in China to treat various kinds of diseases including virus hepatitis. However, the molecular mechanisms underlying its hepatoprotective effects remains elusive. In the present study, primary human hepatocytes were employed to elucidate the protective effects and molecular mechanisms of matrine. We observed that low concentrations of matrine had no significant impact on albumin secretion, but high concentrations (>140 mg/L) of matrine decreased the albumin secretion in hepatocytes. Western blot data indicated that matrine at 140 mg/L at 72 h induced protein expression of CYP2A6, CYP2B6 and CYP3A4. Furthermore, high concentrations of matrine reduced LDH and AST levels and were cytotoxic to hepatocytes, leading to a decreased cell viability and total protein amount. Moreover, low concentrations of matrine, enhanced the ECOD activity and decreased the level of NO2 (-) induced by cytokines in human hepatocytes. Taken together, the present study sheds novel light on the molecular mechanisms of matrine and potential application of matrine in hepatic diseases.

Use of primary human liver cells originating from discarded grafts in a bioreactor for liver support therapy and the prospects of culturing adult liver stem cells in bioreactors: a morphologic study.

INTRODUCTION: The development of a bioreactor providing a three-dimensional network of interwoven capillary membranes with integrated oxygenation and decentralized mass exchange enables the culture of primary human liver cells from discarded donor organs for extracorporeal liver support. METHODS: Primary liver cells were isolated from 54 discarded organs (donor age 56.7+/-13.2 years). Between 2.8x10(10) and 6.4x10(10) parenchymal cells (PC) were cocultured with nonparenchymal cells (NPC) of the same organ in bioreactors (n=36). The metabolic activity of the cells was regularly determined during culture. The cell morphology and ultrastructure were investigated after culture periods of 1 to 5 weeks. RESULTS: Cell metabolism was maintained over at least 3 weeks after a phase of adaptation lasting 2 to 3 days. Through the use of transmission electron microscopy and immunohistochemistry, it was demonstrated that PC and NPC spontaneously formed tissue-like structures. Vascular cavities (CD 31 immunoreactivity [IR]) and bile duct-like channels (CK 19 IR), both exhibiting proliferation activity (Ki-67 IR), were regularly distributed. Some of the bile duct-like channels showed similarities to the Canals of Hering found in the natural liver. Cells expressing morphologic and antigenic characteristics of adult liver stem cells (CD 34 IR and c-kit IR) and areas with cells that showed both hepatocyte and biliary characteristics were detected. CONCLUSION: The results show that primary human liver cells obtained from discarded donor organs recover and can be maintained in bioreactors for clinical liver support therapy. In addition, initial observations on adult liver stem-cell culture in bioreactors are presented.

Time course of primary liver cell reorganization in three-dimensional high-density bioreactors for extracorporeal liver support: an immunohistochemical and ultrastructural study.

To enable extracorporeal liver support based on the use of primary liver cells, culture models supporting the maintenance of cell integrity and function in vitro are required. In this study the cell organization and ultrastructure of primary porcine hepatocytes cocultured with nonparenchymal cells in three-dimensional high-density bioreactors were analyzed after 10, 20, and 30 days of culture by immunohistochemistry and transmission electron microscopy. Biochemical data showed that metabolic activity of the cells in the system was relatively stable over at least 20 days. Immunohistochemical studies were performed in comparison with donor organ biopsies. They showed that hepatocytes and nonparenchymal cells reaggregated in bioreactors, forming structures partly resembling natural liver parenchyma. Bile duct-like structures characterized by cytokeratin 7 (CK-7) immunoreactivity (IR) were regularly detected. Nonparenchymal cells (vimentin IR) formed sinusoidal-like structures within parenchymal cell aggregates. Proliferative activity (Ki-67 IR) increased over time. The detection of collagen I and laminin indicated the production of extracellular matrix components within bioreactors. The results showed that primary liver cell reorganization and long-term maintenance of their differentiated state were achieved within the bioreactors The findings on cell proliferation indicated that the culture model is also of interest for further in vitro studies on cell regeneration and tissue formation.

"Blogs" and "wikis" are valuable software tools for communication within research groups.

Appropriate software tools may improve communication and ease access to knowledge for research groups. A weblog is a website which contains periodic, chronologically ordered posts on a common webpage, whereas a wiki is hypertext-based collaborative software that enables documents to be authored collectively using a web browser. Although not primarily intended for use as an intranet-based collaborative knowledge warehouse, both blogs and wikis have the potential to offer all the features of complex and expensive IT solutions. These tools enable the team members to share knowledge simply and quickly-the collective knowledge base of the group can be efficiently managed and navigated.

Antimalarial artemisinin drugs induce cytochrome P450 and MDR1 expression by activation of xenosensors pregnane X receptor and constitutive androstane receptor.

Artemisinin drugs are of utmost importance in the treatment of malaria, because they represent the sole class of therapeutically used antimalarial drugs to which malaria parasites have not yet developed resistance. The major disadvantage of these medicines is the comparatively high recrudescence rate, which has been attributed to the remarkable decrease of artemisinin plasma concentrations during multiple dosing. Autoinduction of CYP2B6-mediated metabolism has been implicated as the underlying mechanism. So far, the molecular mechanism of induction by artemisinin has not been resolved. Because the xenosensors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) have been shown to mediate induction of drug-metabolizing enzymes and drug transporters, we investigated the hypothesis that artemisinin induces cytochrome P450 expression by activating PXR and/or CAR. By combining in vitro transfection methods and quantitative analyses of gene expression in cell lines and primary human hepatocytes, we here show that artemisinin drugs activate human PXR as well as human and mouse CAR and induce the expression of CYP2B6, CYP3A4, and MDR1 in primary human hepatocytes and in the human intestinal cell line LS174T. Furthermore, we demonstrate that artemisinin acts as a ligand of both nuclear receptors, because it modulates the interaction of the receptors with coregulators. In conclusion, activation of PXR and CAR and especially the resulting induction of CYP3A4 and MDR1 demonstrate that artemisinin has a higher risk of potential drug interactions than anticipated previously.

The SlideReactor--a simple hollow fiber based bioreactor suitable for light microscopy.

Most bioartificial liver support systems are based on hollow fiber capillaries within modified dialysis cartridges or more sophisticated bioreactor constructions. Due to their design microscopic follow-up of reorganization and growth of tissue between the hollow fibers is not possible. The SlideReactor is a simple hollow fiber based bioreactor construction suitable for light microscopy and time-lapse video observation. The SlideReactor offers a cell compartment separated from a medium inflow and outflow compartment. Cell compartment access ports enable easy filling of the cell compartment with cell suspension, as well as fixation of the tissue. For more complex procedures or full access to all the cells, the bioreactor can be opened easily by cutting the silicone seal with a scalpel. Due to its simple design and the utilization of standard materials, it could serve as a suitable, cost-efficient tool to evaluate the behavior of cells cultured between hollow fiber capillaries. The paper describes the production process: similar to open source projects in software engineering, we would like to propose the concept as an open platform to anyone interested in hollow fiber based cell culture.

In vitro evaluation of the transportability of viable primary human liver cells originating from discarded donor organs in bioreactors.

BACKGROUND: The use of primary human liver cells obtained from discarded donor organs is increasingly favored for cell-based extracorporeal liver support systems. However, as cryopreservation of primary human hepatocytes causes a significant loss of metabolic activity, the transport of bioreactors with viable liver cells is required. The aim of this study was to evaluate the impact of two major potential threats to viable cells during transport: temperature changes and mechanical stress. METHODS: In each experiment three hollow fiber-based bioreactors were charged with primary human liver cells originating from the same discarded donor organ and were simultaneously kept under culture conditions for 8 days. In total, 18 bioreactors were evaluated. On the fifth day the bioreactors were exposed to hypothermia (4 degrees C, n = 3), to hyperthermia (42 degrees C, n = 3), or served as normothermic controls (37 degrees C, n = 3). In a second test series bioreactors were exposed to vibration (21 Hz for 20 min, thereafter 7 Hz for 160 min, n = 3), or were operated as control cultures (n = 6). The release of hepatocyte-specific enzymes was determined as an indicator for cell damage. RESULTS: Hypothermic stress resulted in a significant release of transaminases and led to disturbances of the histological integrity, all indicating a high degree of cell damage. When compared with the control cultures, hyperthermia and mechanical stress in terms of vibration had no significant effect on the cells. CONCLUSION: The transport of hollow fiber bioreactors charged with viable primary human liver cells appears to be feasible in transport monitors for perfusion and temperature control.

Effects of human hepatocyte growth factor on the proliferation of human hepatocytes and hepatocellular carcinoma cell lines.

BACKGROUND: Hepatocyte growth factor (HGF) has been suggested to initiate both hepatocyte and tumor cell proliferation after partial hepatectomy, thereby supporting local tumor recurrence. The aim of this study was to clarify the role of HGF in the regeneration of human hepatocyte and the growth of residual hepatocellular carcinoma cells after liver resection. PATIENTS/METHODS: 36 patients who underwent partial hepatectomy for hepatocellular carcinoma (HCC) or living liver donation have been analyzed for HGF serum levels at day -1 through day 5 following surgery using an enzyme-linked immunosorbent assay. Isolated human hepatocytes and HCC cell lines (Hep 3B, Hep G2) were treated either with recombinant human (rh)-HGF, or sera from the 36 patients in the presence or absence of anti-HGF in order to measure their proliferative capacity using (3)H-thymidine incorporation. RESULTS: Basal HGF levels were significantly higher in HCC than in healthy patients (1,573 +/- 131 vs. 778 +/- 64 pg/ml; p < 0.001), however, the postoperative rise of HGF in healthy patients was higher (9,608 +/- 3111 vs. 2,060 +/- 148 pg/ml) than in HCC patients. Incubation of human hepatocytes and Hep 3B cells with rh-HGF revealed a dose-dependent increase in DNA synthesis, while anti-HGF partially abolished this effect. Sera from normal and resected HCC patients stimulated DNA synthesis only in human hepatocytes, whereas it was inhibited in HCC cell lines. CONCLUSION: HGF plays an important role in hepatocyte proliferation but contrary to in vitro results, HGF does not play a major role for the progression of hepatocarcinoma cells in vivo.