[Improved patient safety through a clinical decision support system in laboratory medicine]. / Verbesserte Patientensicherheit durch "clinical decision support systems" in der Labormedizin.

BACKGROUND: Laboratory diagnostics are essential for diagnosis, initiation of therapy, and monitoring of patients. Laboratory results that are overlooked or incorrectly interpreted lead to adverse events and endanger patient safety. Clinical decision support systems (CDSSs) may facilitate appropriate interpretation of results and subsequent medical response. OBJECTIVES: The research project on digital laboratory medicine (AMPEL) aims at developing a CDSS based on laboratory diagnostics, which supports practitioners in ensuring the necessary medical consequences. MATERIALS AND METHODS: A literature review of CDSSs describes the current state of research. The research project AMPEL is presented with its objectives, challenges, and first results. Furthermore, the development of a framework and reporting system is illustrated through the clinical example of severe hypokalemia. RESULTS AND CONCLUSION: Through interdisciplinary development and constant optimization, a specific CDSS with high acceptance among clinicians was developed. Initial results in the case of severe hypokalemia show a positive effect on patient care. Thereby, more complex frameworks such as sepsis diagnostics or acute coronary syndrome are implemented. The limited availability of standardized and digital clinical data is challenging. In addition to the application of classic decision trees in CDSS, the use of machine learning offers a promising perspective for future developments.

[Lipid-lowering therapy in the elderly : Who profits from which target values?] / Lipidsenkende Therapie im Alter : Wer profitiert von welchem Zielwert?

Lowering low-density lipoprotein (LDL) cholesterol levels has been proven to reduce the incidence of cardiovascular and cerebrovascular events and mortality. So far recommendations have not provided information as to a meaningful duration of cholesterol-lowering therapy and were largely guided by economic constraints and limited therapeutic options. In light of the decline in the price of statins, the essential therapeutic agent and the increased efficacy of therapeutic options, treatment can nowadays be geared to target values that can be expected to have an optimal effect even in old age. The most favorable level of LDL-cholesterol for primary prevention is around and below 100 mg/dl, provided continuous adherence to these low levels from adolescence onwards. With later onset of cholesterol reduction the existence of initial atheromatous deposits must be expected. Therefore, with age and the manifestation of other risk factors the optimal treatment targets increasingly converge to those for which experience has been gained from secondary prevention. Both measurements of the effect of cholesterol lowering on the volume of atheromatous plaques and of the incidence of vascular events indicate a target for LDL-cholesterol well below 70 mg/dl and in the range 50-60 mg/dl. At the onset of cholesterol lowering in advanced age, a smaller effect has to be expected but due to the increasing incidence rate of vascular events a higher number of events may be avoided; thus, the efficiency does not necessarily decrease; however, long-term studies indicate that earlier cholesterol lowering provides an advantage for more than a decade, in terms of preventing vascular disease, which tends to increase. Therefore, optimal cardiovascular prevention involves moderate measures to maintain the LDL-cholesterol below 100 mg/dl lifelong from childhood on.

Metastatic efficiency of tumour cells can be impaired by intraoperative cell salvage process: truth or conjecture?

The use of salvaged blood in oncological surgery has been a matter of controversy over the years. This is due to the concern of systemic dissemination of reinfused tumour cells. Recent literature, across disciplines, has shed considerable light on its safety in terms of tumour recurrence, progression and overall survival rates. This clinical safety demonstrates the apparent metastatic inefficiency of reinfused tumour cells. The proof of this concept comes from various studies that have shown that salvaged blood has no tumour cells, or has a significantly lower count as compared to the patient's original circulatory tumour load. Recently, we took a step further and found that the tumour cells in the salvaged blood lose the capacity to replicate. In this review, we revisited the safety of salvaged blood from the point of view of metastatic potential. We have presented basic and applied science evidence regarding the innocuous nature of tumour cells that have been subjected to the cell salvage process. The understanding of the metastatic efficiency or the lack of it in tumour cells subjected to salvage process is key to allay the concerns conventionally associated with the use of salvaged blood in tumour surgery. Based on the available literature, we surmise that the prevalent apprehensions on the usage of salvaged blood are ill-founded and further substantiate why tumour cells in the salvaged blood could be regarded as cells with non-metastatic potential.

Drying kinetics of deformable and cracking nano-porous gels.

The desiccation of porous materials encompasses a wide range of technological and industrial processes and is acutely sensitive to the hierarchical structure of the porous materials resulting in complex dynamics which are challenging to unravel. Macroscopic observations of the surface and geometry of model colloidal gels during desiccation under controlled air flow highlight the role of crack formation in drying. The density of cracks and their rate of appearance depend on the initial solid fraction of the gels and their adherence to the substrate. While under certain conditions cracking leads to an increase of the drying rate, in other cases cracking allows for its conservation over an extended period of the drying process. Nevertheless, as long as the sample is saturated with water, each piece within the sample shrinks isotropically as if it were an independent drying system. By simulating the airflow around the sample and inside the crack cavities, we show the existence of a perturbation in the air velocity in the vicinity of the crack cavity whose scale depends on the aspect ratio (depth/width) of the latter. On this basis, we propose a simple model which predicts the observed drying rate variations encountered while the sample cracks; and further enables to simulate the desiccation for a designated crack density.

[PCSK9 - "missing link" in familial hypercholesterolemia : New therapeutic options in hypercholesterolemia and coronary artery disease]. / PCSK9 - "missing link" der familiären Hypercholesterinämie : Neue Therapieoptionen bei Hypercholesterinämie und KHK.

Lowering plasma low-density lipoprotein cholesterol (LDL-C) levels to individual therapeutic goals is one of the most effective measures for the prevention of cardiovascular disease. Besides dietary measures, this can be achieved pharmaceutically by inhibition of hepatic cholesterol synthesis with statins or inhibition of intestinal cholesterol absorption (e.g., ezetimibe and bile acid sequestrants). Decisive for lowering LDL is an increased hepatic uptake of circulating LDL via an increase in LDL receptors (LDLR) in hepatic cell membranes. The formation of new LDLR and recirculation of existing LDLR play a decisive role in this process. An important modulator of LDLR is proprotein convertase subtilisin/kexin type 9 (PCSK9). In the last years genetic studies have identified several mutations in the PCSK9 gene leading to a gain of function and carriers of these mutations suffer from autosomal dominant hypercholesterolemia. In contrast, carriers of PCSK9 loss of function mutations show very low plasma LDL-C concentrations and a markedly reduced risk for coronary artery disease. These fundamental discoveries have sparked the development of a completely novel therapeutic approach to treating hypercholesterolemia. At present, inhibition of PCSK9 by monoclonal antibodies presents the most promising therapeutic approach. First human antibodies were recently approved as the first immunotherapeutic agents for the treatment of severe hypercholesterolemia and in patients with statin intolerance. An additional PCSK9 antibody is presently being studied in phase III clinical trials.

LC-MS/MS-based quantification of cholesterol and related metabolites in dried blood for the screening of inborn errors of sterol metabolism.

Smith-Lemli-Opitz syndrome (SLOS) is an inherited metabolic disease in the cholesterol biosynthesis pathway which is characterised by accumulation of 7- and 8-dehydrocholesterol and by reduced cholesterol concentrations in all tissues and body fluids. With this study, we developed a new, rapid, robust and high-throughput tandem mass spectrometric method as routine application for the selective SLOS screening and therapy monitoring in serum and dried blood. After protein precipitation of 10 µL serum or 4.7 mm dried blood spot, the sum of 7- and 8-dehydrocholesterol (DHC) was analysed by rapid chromatography combined with tandem mass spectrometry. Method comparison with GC-MS was performed for 46 serum samples. A comparison between serum and corresponding dried blood spots for DHC and cholesterol was performed with 40 samples from SLOS patients. Concentrations of DHC and cholesterol were analysed in 2 dried blood samples from newborns with SLOS and 100 unaffected newborns. Intra- and inter-assay variabilities ranged between 3.7 and 17.7% for serum and dried blood spots. Significant correlations between the new LC-MS/MS method and GC-MS were determined for DHC (r = 0.937, p < 0.001) and for cholesterol (r = 0.946, p < 0.001). Significant coefficients of correlation between serum and dried blood spot samples above 0.8 were calculated for both analytes. A cut-off value of 5.95 for the ratio of DHC/cholesterol (multiplied by 1000) was found to distinguish newborns diagnosed with SLOS from normal newborns in a retrospective analysis after 5 years. The developed method enables a rapid quantification of the sum parameter 7- and 8-DHC in newborns and SLOS patients under therapy in serum as well as dried blood spot samples.

Fibrinogen is not a prognostic factor for response to HELP-apheresis in sudden sensorineural hearing loss (SSHL).

Higher levels of fibrinogen or cholesterol were associated with improved hearing recovery in SSHL patients after treatment with HELP-apheresis (Heparin-induced extracorporeal LDL precipitation apheresis). The present trial was performed to demonstrate HELP-related effects on relevant metabolic and inflammatory parameters in the context of SSHL treatment. In the framework of a single arm non-controlled trial, we investigated the variation of metabolic and inflammatory parameters using HELP-apheresis for a defined group of 100 patients with SSHL. Based on cut off inclusion criteria (Serum LDL-cholesterol >1.6 g/l and/or fibrinogen >2.0 g/l, SSHL in minimum three frequencies more than 30 dB, time after event not longer than 6 days), the protocol followed a strict time line with one single shot HELP-apheresis and follow-up monitoring including laboratory parameters at six defined time points. If HELP-apheresis could not effect improvement of hearing on day 5, additional corticosteroid treatment was applied. Concentration of anti-inflammatory IL-10 increased while other proinflammatory parameters declined. Serum levels of all measured sterols and apolipoproteins decreased significantly. None of the investigated parameters were suitable to predict hearing improvement of the patients. Levels of fibrinogen and LDL-cholesterol were not prognostic for outcome after HELP-apheresis. A significant (p < 0.001) increase of anti-inflammatory IL-10 after apheresis was notable, while most of the proinflammatory parameters declined. Despite the limited validity of a single arm non-controlled trial, these alterations on immune modulating factors indicate possible secondary pleiotropic effects caused by HELP-apheresis.

Preanalytical standardization for reactive oxygen species derived oxysterol analysis in human plasma by liquid chromatography-tandem mass spectrometry.

The analysis of the oxysterols 7-keto-, 7-α/ß-hydroxy-, 5α,6α-epoxy-, 5ß,6ß-epoxycholesterol and cholestane-3ß,5α,6ß-triol derived from reactive oxygen species (ROS) is of interest as biomarkers in the field of atherosclerosis. Preanalytical validation is a crucial point to minimize the susceptibility of oxysterols to in vitro autoxidation. The aim of this study was to standardize a preanalytical protocol for ROS-derived oxysterol analysis by liquid chromatography-tandem mass spectrometry in human plasma. Sample matrices were compared and stability of free oxysterols in whole blood and EDTA-plasma was investigated with regard to short-term storage until sample preparation, freeze-thaw cycles, addition of butylated hydroxytoluene and long-term storage up to 1 year at different temperatures (-20 °C, -80 °C and -130 °C) as well as different storage containers (safe-lock tubes, cryo tubes and straws). Sample preparation prior LC-MS/MS analysis was reduced to a simple concentration and protein precipitation step. Storing EDTA-whole blood for 30 min at room temperature resulted in <25% concentration changes, within acceptable change limits (ACL). In freshly prepared plasma samples, free oxysterols were stable for 90 min stored at 4 °C with concentration changes <23.5% (within ACL). Up to nine freeze-thaw cycles did not affect analyte concentrations (concentration change -8.5% to +5.0%). 7-Ketocholesterol was stable for 2 years stored <-80 °C; concentration changes below 20.5% (within ACL). The remaining oxysterols were stored for a maximum of 2-4 weeks without exceeding ACL. The addition of BHT did not reveal improvement in analyte stability for storage at -80 or -130 °C. We developed a standardized preanalytical protocol for oxysterol analysis based on LC-MS/MS, compared cryobanking conditions for each oxysterol and present data for long-term storage up to 2 years.

Treatment of severe, nonfulminant acute hepatitis B with lamivudine vs placebo: a prospective randomized double-blinded multicentre trial.

Acute hepatitis B virus (aHBV) infection can lead to fulminant liver failure, which likely is prevented by early lamivudine therapy. Even nonfulminant but severe acute hepatitis B can lead to significant morbidity and impaired quality of life. Therefore, lamivudine was evaluated in patients with severe aHBV in a placebo-controlled trial. Patients with severe aHBV infection (ALT >10× ULN, bilirubin >85 µm, prothrombin time >50%) were prospectively treated with lamivudine 100 mg/day or with placebo within 8 days after the diagnosis. The primary end point was time to bilirubin <34.2 µm. Secondary end points were time to clear HBsAg and HBV-DNA, development of anti-HBs and normalization of ALT. Eighteen cases were randomized to lamivudine, 17 to placebo. 94% of patients were hospitalized. No individual progressed to hepatic failure; all but one patient achieved the primary end point. Due to smaller than expected patient numbers, all study end points did not become statistically significant between treatment arms. Median time end points [in days] were bilirubin <34.2 µm (26.5 vs 32), ALT normalization (35 vs 48) and HBsAg clearance (48 vs 67) referring to earlier recovery under lamivudine, in contrast to loss of HBV-DNA (62 vs 54) and development of anti-HBs (119 vs 109). In all but two patients (one in every group), HBsAg clearance was reached in the study. Adverse events occurred more frequently during lamivudine therapy, but did not reach statistical significance. Lamivudine may ameliorate severe aHBV infection, but limited patient numbers prevented definite conclusions.

Peer problems are associated with elevated serum leptin levels in children.

BACKGROUND: Leptin is thought to act as an important mediator in stress reactions. To date, no study has examined the association between psychological stress and leptin levels in children. This study aimed to assess the association between emotional symptoms and peer problems and serum leptin levels in children aged 10 years of the two population-based GINI-plus and LISA-plus birth cohorts. METHOD: Cross-sectional data from 2827 children aged 10 years were assessed with regard to leptin concentrations in serum and behavioral problems using the parent-reported Strengths and Difficulties Questionnaire (SDQ). Linear regression modeling was applied to determine the likelihood of elevated leptin levels in children with emotional symptoms and peer problems, controlling for socio-economic status (SES), body mass index (BMI), fasting serum leptin levels, pubertal development and sex hormones. RESULTS: We found that increases in emotional symptoms (exp ß adj = 1.03, s.e. = 0.02, p < 0.04) and peer problems (exp ß adj = 1.05, s.e. = 0.01, p = 0.0001) were significantly associated with higher serum leptin levels controlled for BMI and sociodemographic factors. Similar results were found when the fasting serum leptin sample was examined (exp ß adj = 1.08, s.e. = 0.04, p = 0.0294). Gender-stratified analyses showed a significant relationship between serum leptin and peer problems in girls (exp ß adj = 1.05, s.e. = 0.02, p = 0.03), and a borderline significant association in boys (exp ß adj = 1.04, s.e. = 0.02, p = 0.05). CONCLUSIONS: Children with peer problems have higher stress and eat more, acquire a higher body fat mass and thus, through increased leptin resistance, exhibit higher leptin levels.

Effects of immunosuppression on alpha and beta cell renewal in transplanted mouse islets.

AIMS/HYPOTHESIS: Immunosuppressive drugs used in human islet transplantation interfere with the balance between beta cell renewal and death, and thus may contribute to progressive graft dysfunction. We analysed the influence of immunosuppressants on the proliferation of transplanted alpha and beta cells after syngeneic islet transplantation in streptozotocin-induced diabetic mice. METHODS: C57BL/6 diabetic mice were transplanted with syngeneic islets in the liver and simultaneously abdominally implanted with a mini-osmotic pump delivering BrdU alone or together with an immunosuppressant (tacrolimus, sirolimus, everolimus or mycophenolate mofetil [MMF]). Glycaemic control was assessed for 4 weeks. The area and proliferation of transplanted alpha and beta cells were subsequently quantified. RESULTS: After 4 weeks, glycaemia was significantly higher in treated mice than in controls. Insulinaemia was significantly lower in mice treated with everolimus, tacrolimus and sirolimus. MMF was the only immunosuppressant that did not significantly reduce beta cell area or proliferation, albeit its levels were in a lower range than those used in clinical settings. CONCLUSIONS/INTERPRETATION: After transplantation in diabetic mice, syngeneic beta cells have a strong capacity for self-renewal. In contrast to other immunosuppressants, MMF neither impaired beta cell proliferation nor adversely affected the fractional beta cell area. Although human beta cells are less prone to proliferate compared with rodent beta cells, the use of MMF may improve the long-term outcome of islet transplantation.

Photoperiodic variations of the polysialylated form of neural cell adhesion molecule within the hypothalamus and related reproductive output in the ewe.

Cellular mechanisms induced by melatonin to synchronise seasonal reproduction in several species, including sheep, remain unclear. We sought to evaluate the scale and physiological significance of neural plasticity in order to explain the delay between the change of duration of melatonin secretion and the change of reproductive status following a transition from long days (LD, 16 h light/24 h) to short days (SD, 8 h light/24 h) and from SD to LD. Using Western blots in ovariectomised oestradiol-replaced ewes, we evaluated the content of the polysialylated form of neural cell adhesion molecule (PSA-NCAM), a plasticity marker, in the hypothalamus. From day 15 following a transition to SD, most hypothalamic areas showed a decrease of PSA-NCAM level that was particularly significant in the preoptic area (POA). Following a transition to LD, PSA-NCAM content increased at day 15 in most regions except in the premammillary hypothalamic area (PMH) in which a significant decrease was noted. The functional importance of PSA-NCAM variations for seasonal reproduction was assessed for the PMH and POA. PSA-NCAM was degraded by stereotaxic injections of endoneuraminidase N and luteinising hormone (LH) secretion was recorded in treated and control ewes. Degradation of PSA-NCAM in the PMH in SD-treated ewes failed to produce a significant effect on LH secretion, whereas a similar treatment in the POA before a transition to SD delayed activation of the gonadotroph axis in two-thirds of the ewes. Our results suggest that the photoperiod controls variations of the hypothalamic content of a plasticity marker and that these might be important for the regulation of seasonal reproduction, particularly in the POA.

Tetrahydrobiopterin (BH4) in PKU: effect on dietary treatment, metabolic control, and quality of life.

BACKGROUND: Tetrahydrobiopterin (BH(4))-sensitive phenylketonuria (PKU) can be treated with sapropterin dihydrochloride. We studied metabolic control and health-related quality of life (HRQoL) in PKU patients treated with BH(4). SUBJECTS AND METHODS: Based on the review of neonatal BH(4) test results and mutation analysis in 41 PKU patients, 19 were identified as potentially BH(4)-sensitive (9 females, 10 males, age 4-18 years). We analyzed phenylalanine (phe) concentrations in dried blood samples, nutrition protocols, and HRQoL questionnaires (KINDL(®)) beginning from 1 year before, during the first 42 days, and after 3 months of BH(4) therapy. RESULTS: Eight BH(4)-sensitive patients increased their phe tolerance (629 ± 476 vs. 2131 ± 1084 mg, p = 0.006) while maintaining good metabolic control (phe concentration in dried blood 283 ± 145 vs. 304 ± 136 µM, p = 1.0). Six of them were able to stop dietary protein restriction entirely. BH(4)-sensitive patients had average HRQoL scores that were comparable to age-matched healthy children. There was no improvement in HRQoL scores after replacing classic dietary treatment with BH(4) supply, although personal reports given by the patients and their parents suggest that available questionnaires are inappropriate to detect aspects relevant to inborn metabolic disorders. DISCUSSION: BH(4) can allow PKU patients to increase their phe consumption significantly or even stop dietary protein restrictions. Unexpectedly, this does not improve HRQoL as assessed with KINDL(®), partly due to high scores even before BH(4) therapy. Specific questionnaires should be developed for inborn metabolic disorders.

[Guidelines-oriented diagnostics of dyslipidemia]. / Leitliniengerechte Diagnostik von Dyslipidämien.

Cardiovascular diseases are the main cause of mortality for patients with advanced age. Changes in lipid metabolism are common and play an important role as key risk factors. This article explains an approach in the diagnostics of dyslipidemia according to the current guidelines. First, the overall risk evaluation of cardiovascular mortality based on the current chart has to be evaluated. Depending on these results an individual LDL-C goal should be defined. The article also includes other relevant cardiovascular risk factors which were not included in the established risk charts. Furthermore, the main innovative biomarkers are discussed in their possible applications and diagnostic value.

Effect of a two-week treatment with low dose of ortho-substituted polychlorinated biphenyls (PCB104 and PCB153) on VEGF-receptor system expression in the choroid plexus in adult ewes.

Ortho-substituted polychlorinated biphenyl (PCB) congeners, which constitute a large part of PCB residues found in the environment and in animal tissues, are known to exert potent vascular effects and can activate endothelial cells in the periphery and in the brain. The choroid plexus (CP) is responsible for cerebrospinal fluid (CSF) production and its epithelial cell layer is responsible for structure and functions of the blood-CSF barrier. The aims of this study were: 1) to investigate if environmentally relevant doses of PCB153 and similar doses of PCB104 caused changes in the expression of vascular endothelial growth factor (VEGF)--receptor system, which maintains CP function, and 2) to determine the level of both congeners in blood plasma after their oral administration. Studies of both congeners were performed on ovariectomized ewes treated per os with low doses (0.1 mg/kg, three times a week for two weeks) of PCB153 (n = 4) or PCB104 (n = 4) and vehicle (control, n = 4). The effects of PCB153 and PCB104 treatment on mRNA expression of two isoforms of VEGF (VEGF120 and VEGF164) and their receptors Flt-1 and KDR were determined using real-time PCR. Plasma concentration of PCBs was measured using high resolution chromatography/tandem mass spectrometry (HRGC/MS-MS). We observed that neither PCB153 nor PCB104 significantly altered the mRNA of the VEGF-receptor system in the CP. In PCB treated animals plasma concentration of PCB153 (1.425 +/- 0.16 ng/g of dry mass, DM) was about 150 times higher than PCB104 (0.009 +/- 0.007 ng/g DM). In control animals the PCB153 level was 0.14 +/- 0.031 ng/g DM, while the PCB104 level was below detection level. This indicates that increase in plasma PCB153 concentration to levels similar to those reported in humans and of PCB104 concentration to levels 100 times higher than those found in human plasma did not affect the VEGF-receptor system in the CP in adult ewes. The significantly lower increase of PCB104 than PCB153 concentration in blood after oral administration suggests different absorption of both congeners from the digestive tract.

Phenotypic and genetic variation in leptin as determinants of weight regain.

AIMS: Over 75% of obese subjects fail to maintain their weight following weight loss interventions. We aimed to identify phenotypic and genetic markers associated with weight maintenance/regain following a dietary intervention. SUBJECTS AND METHODS: In the 2-year Dietary Intervention Randomized Controlled Trial, we assessed potential predictors for weight changes during the 'weight loss phase' (0-6 months) and the 'weight maintenance/regain phase' (7-24 months). Genetic variation between study participants was studied using single-nucleotide polymorphisms in the leptin gene (LEP). RESULTS: Mean weight reduction was -5.5% after 6 months, with a mean weight regain of 1.2% of baseline weight during the subsequent 7-24 months. In a multivariate regression model, higher baseline high-molecular-weight adiponectin was the only biomarker predictor of greater success in 0- to 6-month weight loss (ß = -0.222, P-value = 0.044). In a multivariate regression model adjusted for 6-month changes in weight and various biomarkers, 6-month plasma leptin reduction exhibited the strongest positive association with 6-month weight loss (ß = 0.505, P-value < 0.001). Conversely, 6-month plasma leptin reduction independently predicted weight regain during the following 18 months (ß = -0.131, P-value < 0.013). Weight regain was higher among participants who had a greater (top tertiles) 6-month decrease in both weight and leptin (+3.4% (95% confidence interval 2.1-4.8)) as compared with those in the lowest combined tertiles (+0.2% (95% confidence interval -1.1 to 1.4)); P-value < 0.001. Weight regain was further significantly and independently associated with genetic variations in LEP (P = 0.006 for both rs4731426 and rs2071045). Adding genetic data to the phenotypic multivariate model increased its predictive value for weight regain by 34%. CONCLUSION: Although greater reduction in leptin concentrations during the initial phase of a dietary intervention is associated with greater weight loss in the short term, plasma leptin reduction, combined with the degree of initial weight loss and with genetic variations in the LEP gene, constitutes a significant predictor of subsequent long-term weight regain.

The junction between cytokines and cell adhesion.

Several aspects of the interactions between growth factors and cell adhesion are described. Recent advances in the field come from the identification of molecules resembling growth factors or growth factor receptors, which bear cell adhesion motifs as well as molecules participating in both cell growth control and adhesion.

Calponin modulates the exclusion of Otx-expressing cells from convergence extension movements.

Otx2, a vertebrate homologue of the Drosophila orthodenticle gene, coordinates two processes in early embryonic development. Not only does it specify cell fate in the anterior regions of the embryo, it also prevents the cells that express it from participating in the convergence extension movements that shape the rest of the body axis. Here we show that, in Xenopus, this latter function is mediated by XclpH3, transcription of which is directly stimulated by Xotx2. XclpH3 is a Xenopus homologue of the mammalian calponin gene, the product of which binds both actin and myosin and prevents the generation of contractile force by actin filaments.

Micropatterns of cell adhesive proteins with poly(ethylene oxide)-block-Poly(4-vinylpyridine) diblock copolymer.

Control of cell shape and behavior through the micropattern technique by spatial immobilization of adhesive proteins on a surface has provided novel insights in several aspects of cell biology, such as tissue morphogenesis, cell growth and cell differentiation, and apoptosis. In this work, we present the use of poly(ethylene oxide-block-poly(4-vinylpyridine) (PEO-b-P4VP) as a non-adhesive background to construct micropatterns of cell adhesive proteins. In the method presented, PEO-b-P4VP is used for its antifouling properties and at the same time, as a photosensitive material to define the micropatterns. The irradiation of PEO-b-P4VP with a short wavelength UV light through photolithographic mask, causes the polymer to crosslink and immobilize in the areas exposed. In the areas non-exposed the polymer can be removed. These areas can be subsequent back filled with the adhesive protein of interest to produce the final micropatterned cell chips.

Plant sterols from rapeseed and tall oils: effects on lipids, fat-soluble vitamins and plant sterol concentrations.

BACKGROUND AND AIMS: Data comparing the impact of different sources of plant sterols on CVD risk factors and antioxidant levels is scarce. We evaluated the effects of plant sterols from rapeseed and tall oils on serum lipids, lipoproteins, fat-soluble vitamins and plant sterol concentrations. METHODS AND RESULTS: This was a double-blinded, randomized, crossover trial in which 59 hypercholesterolemic subjects consumed 25 g/day of margarine for 4 weeks separated by 1 week washout periods. The two experimental margarines provided 2g/day of plant sterols from rapeseed or tall oil. The control margarine had no added plant sterols. The control margarine reduced LDL cholesterol by 4.5% (95% CI 1.4, 7.6%). The tall and rapeseed sterol margarines additionally reduced LDL cholesterol by 9.0% (95% CI 5.5, 12.4%) and 8.2% (95% CI 5.2, 11.4%) and apolipoprotein B by 5.3% (95% CI 1.0, 9.6%) and 6.9% (95% CI 3.6, 10.2%), respectively. Lipid-adjusted beta-carotene concentrations were reduced by both sterol margarines (P<0.017). alpha-Tocopherol concentrations were reduced by the tall sterol compared to the rapeseed sterol margarine (P=0.001). Campesterol concentrations increased more markedly with the rapeseed sterol versus tall sterol margarine (P<0.001). The rapeseed sterol margarine increased while the tall sterol margarine decreased brassicasterol concentrations (P<0.001). CONCLUSIONS: Plant sterols from tall and rapeseed oils reduce atherogenic lipids and lipoproteins similarly. The rapeseed sterol margarine may have more favorable effects on serum alpha-tocopherol concentrations.