Integrating Two Epistemological Goals: Why Shouldn’t We Give It Another Chance?

As Beller, Bender, and Medin (in press) pointed out in their target article, in the contemporary study of culture in psychology, anthropology is virtually invisible. In this commentary, I traced this invisibility to a root conflict in epistemological goals of the two disciplines: Whereas anthropologists value rich description of specific cultures, psychologists aspire to achieve theoretical simplicity. To anthropologists, then, to understand culture is to articulate symbolic systems that are at work in a given location at a given time. In contrast, to psychologists, to understand culture amounts to identifying socio‐cultural variables that moderate psychological effects. These divergent epistemological goals dictate both theoretical perspectives and empirical approaches in both disciplines. Yet, the two goals are both valid and in fact complementary. A renewed effort toward integration of the two goals may enrich both disciplines.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92388/1/j.1756-8765.2012.01201.x.pd

Investigation of stable expressing S/MAR-minicircles for the industrial application in mammalian cell lines

Es gibt unterschiedliche Verfahren zur Manipulation und Modifikation von Zellen zur Expression von rekombinanten therapeutischen Proteinen. Es wird dabei zwischen integrierenden und nicht-integrierenden, episomal vorliegenden Vektoren unterschieden. Der episomal replizierende Vektor pEPI besitzt eine „scaffold matrix attachment region“ (S/MAR, SAR E), die durch Wechselwirkungen mit Proteinen der Kernmatrix eine Bindung an diese vermittelt und für die stabile Replikation und Segregation des Vektors während der Zellteilung verantwortlich ist. In dieser Arbeit wurde die Verwendung eines, auf dem Vektor pEPI basierenden, Minicircles (pEPI-delCM18-Minicircle) zur stabilen Transgenexpression untersucht. Durch die besonderen Eigenschaften dieses Minicircles sollte eine stabile episomale Etablierung des Minicircles im Zellkern ohne Selektionsdruck möglich sein. Es wurde ein stabiles Zwei-Minicircle-Expressionssystem zur Generierung von rekombinanten Antikörpern in CHO-K1-Zellen entwickelt. Es konnte gezeigt werden, dass es überwiegend zu einer episomalen Etablierung der zirkulären Minicircles kommt. Der Minicircle-Transfer führt gerade in CHO-K1-Zellen häufig zu ungerichteten Minicircle-Integrationen in das CHO-Genom und Deletionen innerhalb des Minicircles durch Doppelstrangbrüche. Aufgrund dessen wurde ein Konzept zur Inhibierung der Integration des Minicircles in das Wirtsgenom entwickelt. Darüber hinaus wurde die episomale Etablierung des Minicircles in einer neuen, von humanen Amniozyten abgeleiteten, Zelllinie (CAP) nachgewiesen. Durch Sequenzvergleich des SAR M18 mit dem CHO-K1-Genom konnte gezeigt werden, dass die Gefahr einer Integration über das SAR M18 durch homologe Rekombination gering ist. Es wurde weiterhin ein neues Verfahren zur Generierung von hochreiner Minicircle-DNA entwickelt. Dieses erfordert keine zusätzlichen, z.B. zur Generierung oder Aufreinigung von Minicircle-DNA benötigten, Sequenzen im Ursprungsvektor bzw. Minicircle.A great number of methods for the expression of therapeutic proteins with mammalian cells are well-established. The used DNA-vectors are divided into integrating and non-integrating, episomal vectors. Episomal vectors don´t influence the genomic gene-regulation and –function, therefore, until now, no insertional mutagenesis or cell transformations have been observed. The episomal replicating vector pEPI contains a ‘scaffold matrix attachment region’ (S/MAR, SAR E). This specific region interacts with nuclear matrix proteins and enables the stable episomal vector-replication during the cell cycle. In this thesis, the transgene expression with the pEPI-derived minicircle ‘pEPI-delCM18’ was analysed. This minicircle contains a size-reduced SAR E, the SAR M18, and is lacking in prokaryotic vector parts, e.g. a resistance marker. Therefore, a stable episomal vector-establishment should be possible in the absence of selection pressure. Based on the minicircle pEPI-delCM18, a stable two-minicircle-expression-system in CHO-K1 cells was developed. Thereby minicircles could be detected in the episomal status predominantly. However, additional genomic minicircle-integration events were often detected in CHO-K1 cells. Thus a concept to reduce random integrations was developed. Moreover the stable episomal minicircle-establishment was shown in a new commercially available human cell line (CAP), which is derived from human amniocytes. A sequence alignment of the SAR M18 with two CHO-K1 genomes showed that the minicircle-integration is not mediated by sequence homologies between SAR M18 and CHO-K1 gDNA. Furthermore, a new powerful method for producing high-purity minicircles without any recombination or recognition sites was developed. For this reason, this method offers a fast and easy production of minicircles

Evaluation der Nadelstichdokumentation: Meldeverhalten nach Änderung des Meldesystems

Ziel dieser Studie war die Evaluation des neuen lokalen Meldesystems durch Auswertung der dokumentierten nosokomialen Risikoereignisse. Es konnte gezeigt werden, dass signifikant mehr nosokomiale Risikoereignisse gemeldet wurden (Reduktion Underreporting), dass sich die Zeit zwischen nosokomialem Ereignis und der Meldung verkürzte (Verbesserung Sekundärprophylaxe und Verhinderung Infektion), jedoch sich auch nicht alle Betroffenen an die neue Verfahrensanweisung hielten (Meldewege und Zuständigkeiten nicht jedem bekannt). Hintergrundinfo, Procedere im Visitenkartenformat, Journal-Publikation

The adaptor protein PID1 regulates receptor-dependent endocytosis of postprandial triglyceride-rich lipoproteins.

ObjectiveInsulin resistance is associated with impaired receptor dependent hepatic uptake of triglyceride-rich lipoproteins (TRL), promoting hypertriglyceridemia and atherosclerosis. Next to low-density lipoprotein (LDL) receptor (LDLR) and syndecan-1, the LDLR-related protein 1 (LRP1) stimulated by insulin action contributes to the rapid clearance of TRL in the postprandial state. Here, we investigated the hypothesis that the adaptor protein phosphotyrosine interacting domain-containing protein 1 (PID1) regulates LRP1 function, thereby controlling hepatic endocytosis of postprandial lipoproteins.MethodsLocalization and interaction of PID1 and LRP1 in cultured hepatocytes was studied by confocal microscopy of fluorescent tagged proteins, by indirect immunohistochemistry of endogenous proteins, by GST-based pull down and by immunoprecipitation experiments. The in vivo relevance of PID1 was assessed using whole body as well as liver-specific Pid1-deficient mice on a wild type or Ldlr-deficient (Ldlr-/-) background. Intravital microscopy was used to study LRP1 translocation in the liver. Lipoprotein metabolism was investigated by lipoprotein profiling, gene and protein expression as well as organ-specific uptake of radiolabelled TRL.ResultsPID1 co-localized in perinuclear endosomes and was found associated with LRP1 under fasting conditions. We identified the distal NPxY motif of the intracellular C-terminal domain (ICD) of LRP1 as the site critical for the interaction with PID1. Insulin-mediated NPxY-phosphorylation caused the dissociation of PID1 from the ICD, causing LRP1 translocation to the plasma membrane. PID1 deletion resulted in higher LRP1 abundance at the cell surface, higher LDLR protein levels and, paradoxically, reduced total LRP1. The latter can be explained by higher receptor shedding, which we observed in cultured Pid1-deficient hepatocytes. Consistently, PID1 deficiency alone led to increased LDLR-dependent endocytosis of postprandial lipoproteins and lower plasma triglycerides. In contrast, hepatic PID1 deletion on an Ldlr-/- background reduced lipoprotein uptake into liver and caused plasma TRL accumulation.ConclusionsBy acting as an insulin-dependent retention adaptor, PID1 serves as a regulator of LRP1 function controlling the disposal of postprandial lipoproteins. PID1 inhibition provides a novel approach to lower plasma levels of pro-atherogenic TRL remnants by stimulating endocytic function of both LRP1 and LDLR in the liver

Phytotoxin production in Aspergillus terreus is regulated by independent environmental signals

Secondary metabolites have a great potential as pharmaceuticals, but there are only a few examples where regulation of gene cluster expression has been correlated with ecological and physiological relevance for the producer. Here, signals, mediators, and biological effects of terrein production were studied in the fungus Aspergillus terreus to elucidate the contribution of terrein to ecological competition. Terrein causes fruit surface lesions and inhibits plant seed germination. Additionally, terrein is moderately antifungal and reduces ferric iron, thereby supporting growth of A. terreus under iron starvation. In accordance, the lack of nitrogen or iron or elevated methionine levels induced terrein production and was dependent on either the nitrogen response regulators AreA and AtfA or the iron response regulator HapX. Independent signal transduction allows complex sensing of the environment and, combined with its broad spectrum of biological activities, terrein provides a prominent example of adapted secondary metabolite production in response to environmental competition

Inclusion of additional studies yields different conclusions: Comment on Sedikides, Gaertner, & Vevea (2005), Journal of Personality and Social Psychology

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75100/1/j.1467-839X.2007.00211.x.pd

Применение метода подвижных клеточных автоматов для оптимизации внутренней структуры эндопротеза тазобедренного сустава человека

На основе метода подвижных клеточных автоматов проведено изучение влияния конструкционных изменений эндопротеза тазобедренного сустава человека на деформационные и прочностные свойства, а также динамику генерации и развития повреждений в системе "сустав-эндопротез-бедренная кость". Структура протеза модифицировалась введением в шейку демпфирующих включений и нанесением покрытия на ножку имплантата. Показано, что наличие таких включений практически не изменяет прочность системы, но при этом ведет к заметному увеличению предельной деформации структуры "кость - протез", а также оказывает влияние на динамику зарождения и развития повреждений в костной ткани

Coupling governs entrainment range of circadian clocks

Circadian clock oscillator properties that are crucial for synchronization with the environment (entrainment) are studied in experiment and theory.The ratio between stimulus (zeitgeber) strength and oscillator amplitude, and the rigidity of the oscillatory system (relaxation rate upon perturbation) determine entrainment properties. Coupling among oscillators affects both qualities resulting in increased amplitude and rigidity.Uncoupled lung clocks entrain to extreme zeitgeber cycles, whereas the coupled oscillator system in the suprachiasmatic nucleus (SCN) does not; however, when coupling in the SCN is inhibited, larger ranges of entrainment can be achieved