Variable coordination of cotranscribed genes in Escherichia coli following antisense repression

Background  

A majority of bacterial genes belong to tight clusters and operons, which complicates gene functional studies using conventional knock-out methods. Antisense agents can down-regulate the expression of genes without disrupting the genome because they bind mRNA and block its expression. However, it is unclear how antisense inhibition affects expression from genes that are cotranscribed with the target.     

Do “infectious” prey select for high levels of natural antibodies in tropical pythons?

Natural antibodies (NAbs) constitute an important component in vertebrate immune system, but, in spite of this, have often been dismissed as “non-specific background” signals. We observed a significant positive relationship between water python (Liasis fuscus) body length/age and levels of antibodies reactive with two administered antigens (tetanus and diphtheria). However, no humoral immune response to the antigens was observed. The lack of elevated immune response, and the age-associated increase in antibody titres, strongly suggest that the antibodies consisted of polyreactive NAbs, and that absence of an elevated immune response was caused by such high levels of NAbs that they were able to mask the epitopes of the antigens. In our study area pythons feed mainly on rodents that frequently, before being killed, are able to inflict numerous bites to the snakes. The bites most likely transmit pathogens such as bacteria. As NAbs have been shown to act as a first line defence against bacterial infections, the high levels of NAbs in the pythons may be an adaptation to reduce pathogenic effects of bacteria transmitted by the prey when the snakes are feeding. Thus, the results from present study suggest that NAbs may have an important immunological function by reducing deleterious effects of pathogens in wild populations.     

Arthritis suppression by NADPH activation operates through an interferon-β pathway

Background  

A polymorphism in the activating component of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex, neutrophil cytosolic factor 1 (NCF1), has previously been identified as a regulator of arthritis severity in mice and rats. This discovery resulted in a search for NADPH oxidase-activating substances as a potential new approach to treat autoimmune disorders such as rheumatoid arthritis (RA). We have recently shown that compounds inducing NCF1-dependent oxidative burst, e.g. phytol, have a strong ameliorating effect on arthritis in rats. However, the underlying molecular mechanism is still not clearly understood. The aim of this study was to use gene-expression profiling to understand the protective effect against arthritis of activation of NADPH oxidase in the immune system.     

Assembly Root Cause Analysis: A Way to Reduce Dimensional Variation in Assembled Products

The objective of root cause analysis (RCA) is to make the trouble shooting dimensional error efforts in an assembly plant more efficient and successful by pinpointing the underlying reasons for variation. The result of eliminating or limiting these sources of variation is a real and long term process improvement. Complex products are manufactured in multileveled hierarchical assembly processes using positioning fixtures. A general approach for diagnosing fixture related errors using routine measurement on products, rather than from special measurements on fixtures, is presented. The assembly variation is effectively tracked down into variation in the fixture tooling elements, referred to as locators. In this way, the process engineers can focus on adjusting the locators affected by most variation. However, depending on the assembly process configuration, inspection strategy, and the type of locator error, it can be impossible to completely sort out the variation caused by an individual locator. The reason for this is that faults in different locators can cause identical dimensional deviation in the inspection station. Conditions guaranteeing diagnosability are derived by considering multiple uncoupled locator faults, in contrast to previous research focusing on single or multiple coupled locator faults. Furthermore, even if an assembly is not diagnosable, it is still possible to gain information for diagnosis by using a novel approach to find an interval for each locator containing the true underlying locator variation. In this way, some locators can be excluded from further analysis, some can be picked out for adjustment, and others remain as potential reason for assembly variation. Another way around the problem of diagnosability is to make a higher level diagnosis by calculating the amount of variation originating from different assembly stations. Also, a design for diagnosis approach is discussed, where assembly and inspection concepts allowing for root cause analysis are the objective.