A New Endotoxin Adsorber: First Clinical Application

Abstract: In an open, uncontrolled pilot study, 5 men and 1 woman with suspected gram‐negative sepsis were treated with a new whole‐blood endotoxin adsorption system. Lipopolysaccharide (LPS) adsorption was carried out by hemoperfusion over high‐affinity polymethacrylate‐bound albumin (Fresenius Endotoxin Adsorber EN 500). All patients suffered from endotoxemia (>20 pg/ml LAL) and met at least two systemic inflammatory response syndrome (SIRS) criteria. Four patients suffered from pneumonia due to mechanical ventilation, one from peritonitis, and one from pneumonia and peritonitis. Endotoxin adsorption was very well tolerated, and efficient LPS removal was shown in all patients. Apache II score immediately before immunoadsorption was 23.5 and was 22.3 after the last treatment. All 6 critically ill patients improved substantially and were discharged from the intensive care unit. LPS whole blood immunoadsorption is a promising new method. No side effects have been observed thus far. A large controlled study to prove clinical efficacy in patients with severe sepsis is under way.     

The Transfer Half-life of Morphine-6-glucuronide from Plasma to Effect Site Assessed by Pupil Size Measurement in Healthy Volunteers

Background : Clinical and experimental data suggested a long delay between the plasma concentration versus time course of morphine-6-glucuronide and the time course of its central opioid effects. This study was aimed at the quantification of the transfer half-life (t1/2,ke0) of this delay.

Methods : Pupil size was used as a measure of central opioid effect. Eight healthy volunteers (four men, four women) participated in that single-blind randomized crossover study. Median dosages administered intravenously were 0.5 mg morphine as loading dose followed by 10.7 mg given as infusion over a period of 4.7 h, and 10.2 mg M6G as loading dose followed by 39.1 mg M6G given over a period of 3.7 h. The duration of the infusion was tailored to achieve submaximum pupil constriction. The pupil diameter was assessed every 20 min for approximately 18 h. Values of t1/2,ke0 were obtained by semiparametric pharmacokinetic-pharmacodynamic modeling.

Results : The estimated median t1/2,ke0 of M6G was 6.4 h (range, 2.9-16.2 h), and that of morphine was 2.8 h (range, 1.8-4.4 h). The individual t1/2,ke0 of M6G was always longer than that of morphine. Judged by the concentration at half-maximun effect (EC50) values of the sigmoid pupil size at maximum constriction (Emax) model describing concentration-response relation, M6G was apparently 22 times less potent than morphine (EC50 = 740.5 nm [range, 500-1,520 nm] for M6G and 36.2 nm [range, 19.7-43.3 nm] for morphine). The steepness of the sigmoid Emax model did not significantly differ between morphine and M6G ([gamma] = 1.9 and 2.6, respectively). To produce similar pupil effects, the M6G dose had to be 2.8 times greater than the morphine dose.     

The phenotype of early-onset retinal degeneration in persons with RDH12 mutations

PURPOSE: To describe the retinal dystrophy phenotype associated with mutations in RDH12, the gene encoding a retinoid dehydrogenase/reductase expressed in the photoreceptor cells. METHODS: Sixteen persons from 12 families with pathogenic RDH12 mutations on both alleles were studied. Retinal phenotypes were characterized by ophthalmic examination, including psychophysical and standardized electrophysiological methods and multifocal electroretinography (mfERG). RESULTS: The retinal disease in persons with RDH12 mutations in the homozygous (p.G127X, p.Q189X, p.Y226C, p.A269GfsX1, and p.L274P) or compound heterozygous state (p.R65X/p.A269GfsX1, p.H151D/p.T155I, p.H151D/p.A269GfsX1) was diagnosed initially as Leber congenital amaurosis (LCA) or early-onset retinitis pigmentosa. These individuals appeared to share a common clinical picture, independent of the type of mutation, characterized by poor, yet useful visual function in early life, followed by progressive decline due to both rod and cone degeneration. Marked pigmentary retinopathy, including bone spicules in the peripheral retina, was present in all persons older than age 6, and pronounced maculopathy was evident in persons older than 7 years. A unique view into the progressive nature of the disorder was achieved by evaluation of seven affected persons from three consanguineous families, all carrying the homozygous p.Y226C mutation. CONCLUSIONS: Ophthalmic findings in persons with RDH12 mutations suggest that RDH12 loss-of-function results in a characteristic form of early and progressive rod-cone degeneration distinct from that caused by mutations in other LCA genes. From our data, it seems likely that various clinical designations appropriately describe the diagnosis in these persons, including early-onset retinitis pigmentosa, LCA type II, and childhood retinal dystrophy.     

MRI versus 64-row MDCT for diagnosis of hepatocellular carcinoma

AIM: To compare the diagnostic capability of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) for the detection of hepatocellular carcinoma (HCC) tumour nodules and their effect on patient management.METHODS: A total of 28 patients (25 male, 3 female, mean age 67 ± 10.8 years) with biopsy-proven HCC were investigated with 64-row MDCT (slice 3 mm native,arterial and portal-venous phase, 120 mL Iomeprol,4 mL/s, delay by bolus trigger) and MRI (T1fs fl2d TE/TR 2.72/129 ms, T2tse TE/TR 102/4000 ms, 5-phase dynamic contrast-enhanced T1fs fl3d TE/TR 1.56/4.6,Gadolinium-DTPA, slice 4 mm). Consensus reading of both modalities was used as reference. Tumour nodules were analyzed with respect to number, size, and location.RESULTS: In total, 162 tumour nodules were detected by consensus reading. MRI detected significantly more tumour nodules (159 vs 123, P < 0.001) compared to MDCT, with the best sensitivity for early arterial phase MRI. False-negative CT findings included nodules ≤ 5 mm ( n = 5), ≤ 10 mm ( n = 17), ≤ 15 mm ( n = 12 ), ≤ 20 mm ( n = 4 ), and 1 nodule > 20 mm. MRI missed 2 nodules ≤ 10 mm and 1 nodule ≤ 15 mm. On MRI, nodule diameters were greater than on CT (29.2 ± 25.1 mm, range 5-140 mm vs 24.1 ± 22.7 mm, range 4-129 mm, P < 0.005). In 2 patients, MDCT showed only unilobar tumour spread, whereas MRI revealed additional nodules in the contralateral lobe. Detection of these nodules could have changed the therapeutic strategy. CONCLUSION: Contrast-enhanced MRI is superior to 64-row MDCT for the detection of HCC nodules. Patients should be allocated to interventional or operative treatment according to a dedicated MRI-protocol.     

DNA methylation patterns in lung carcinomas

The genome of epithelial tumors is characterized by numerous chromosomal aberrations, DNA base sequence changes, and epigenetic abnormalities. The epigenome of cancer cells has been most commonly studied at the level of DNA CpG methylation. In squamous cell carcinomas of the lung, CpG methylation patterns undergo substantial changes relative to normal lung epithelium. Using a genome-scale mapping technique for CpG methylation (MIRA-chip), we characterized CpG island methylation and methylation patterns of entire chromosome arms at a level of resolution of ～100 bp. In individual stage I lung carcinomas, several hundred and probably up to a thousand CpG islands become methylated. Interestingly, a large fraction (almost 80%) of the tumor-specifically methylated sequences are targets of the Polycomb complex in embryonic stem cells. Homeobox genes are particularly overrepresented and all four HOX gene loci on chromosomes 2, 7, 12, and 17 are hotspots for tumor-associated methylation because of the presence of multiple methylated CpG islands within these loci. DNA hypomethylation at CpGs in squamous cell tumors preferentially affects repetitive sequence classes including SINEs, LINEs, subtelomeric repeats, and segmental duplications. Since these epigenetic changes are found in early stage tumors, their contribution to tumor etiology as well as their potential usefulness as diagnostic or prognostic biomarkers of the disease should be considered.     

Sensitive J‐coupled metabolite mapping using Sel‐MQC with selective multi‐spin‐echo readout

The selective multiple quantum coherence technique is combined with a read gradient to accelerate the measurement of a specific scalar‐coupled metabolite. The sensitivities of the localization using pure phase encoding and localization with the read gradient are compared in experiments at high magnetic field strength (17.6 T). Multiple spin‐echoes of the selective multiple quantum coherence edited metabolite are acquired using frequency‐selective refocusing of the specified molecule group. The frequency‐selective refocusing does not affect the J‐modulation of a coupled spin system, and the echo time is not limited to a multiple of 1/J to acquire pure in‐phase or antiphase signal. The multiple echoes can be used to accelerate the metabolite imaging experiment or to measure the apparent transverse relaxation T₂. A simple phase‐shifting scheme is presented, which enables the suppression of editing artifacts resulting from the multiple spin‐echoes of the water resonance. The experiments are carried out on phantoms, in which lactate and polyunsaturated fatty acids are edited, and in vivo on tumors, in which lactate content and T₂ are imaged. The method is of particular interest when a fast and sensitive selective multiple quantum coherence editing is necessary, e.g., for spatial three dimensional experiments. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.     

Smooth muscle tissue engineering for hybrid tubular organs: scanning electron microscopic investigations of cell interactions with collagen scaffolds

Tissue engineering of transplantable tubular tissue necessitates a composite approach to assembling the individual components. In the engineering of tubular structures (gastrointestinal, urogenital and vascular tissues) there is a demand for smooth muscle tissue in addition to the primary organ‐specific tissue. This study aims to investigate the interaction of smooth muscle cells on bovine collagen scaffolds cross‐linked with glutaraldehyde under in vitro conditions, using scanning electron microscopy. The density of tissue generated over the 8 week period was demonstrated in terms of: (a) scaffold coverage and attachment; (b) cell density; (c) cell viability deep inside the scaffolds; and (d) cell differentiation. Copyright © 2009 John Wiley & Sons, Ltd.     

EGF and HGF levels are increased during active HBV infection and enhance survival signaling through extracellular matrix interactions in primary human hepatocytes

The hepatitis B virus (HBV) is a major causative agent of chronic liver disease and subsequent liver cirrhosis worldwide. The reduced sensitivity of virus-infected liver cells to apoptosis may play a role in the failure to remove virus-infected cells and eventually promote viral chronicity. The purpose of our study was to investigate whether survival factors induced during compensatory liver regeneration may protect hepatocytes against apoptosis. We evaluated the serum levels of hepatocyte growth factor (HGF) and epidermal growth factor (EGF) in HBV-infected patients and found significant increases in HGF and EGF in patients with active virus infection. In primary human hepatocytes we show that HGF and EGF have a protective effect against CD95-mediated apoptosis and cytotoxic T-cell killing. Simultaneous treatment with both regeneration factors enhanced the cytoprotective effect. The PI 3-K/Akt kinase inhibitor, wortmannin, and the STAT3 pathway inhibitor, Tyrphostin AG490, both effectively attenuated the cytoprotective effect of HGF and EGF. Furthermore, we show an EGF/HGF-dependent upregulation of beta(1)-integrin chains, increased adhesion to extracellular matrix and an increase in focal adhesions, suggesting outside-in signaling from the extracellular matrix as an additional cytoprotective mechanism. Our study demonstrates that HGF and EGF can interfere with CD95-mediated apoptosis and the action of cytotoxic T-cells through multiple mechanisms in human hepatocytes. Together our results argue that a survival mileau generated by activation of liver regeneration factors may be a risk factor for establishing viral persistence.