Knowledge acquisition for case-based reasoning systems

Case-based reasoning (CBR) is a simple idea: solve new problems by adapting old solutions to similar problems. The CBR approach offers several potential advantages over rule-based reasoning: rules are not combined blindly in a search for solutions, solutions can be explained in terms of concrete examples, and performance can improve automatically as new problems are solved and added to the case library. Moving CBR for the university research environment to the real world requires smooth interfaces for getting knowledge from experts. Described are the basic elements of an interface for acquiring three basic bodies of knowledge that any case-based reasoner requires: the case library of problems and their solutions, the analysis rules that flesh out input problem specifications so that relevant cases can be retrieved, and the adaptation rules that adjust old solutions to fit new problems

Invasive disease caused by Haemophilus influenzae in Sweden 1997–2009; evidence of increasing incidence and clinical burden of non‐type b strains

Introduction of a conjugated vaccine against encapsulated Haemophilus influenzae type b (Hib) has led to a dramatic reduction of invasive Hib disease. However, an increasing incidence of invasive disease by H. influenzae non‐type b has recently been reported. Non‐type b strains have been suggested to be opportunists in an invasive context, but information on clinical consequences and related medical conditions is scarce. In this retrospective study, all H. influenzae isolates ( n  =   410) from blood and cerebrospinal fluid in three metropolitan Swedish regions between 1997 and 2009 from a population of approximately 3 million individuals were identified. All available isolates were serotyped by PCR ( n  =   250). We observed a statistically significant increase in the incidence of invasive H. influenzae disease, ascribed to non‐typeable H. influenzae (NTHi) and encapsulated strains type f (Hif) in mainly individuals >60 years of age. The medical reports from a subset of 136 cases of invasive Haemophilus disease revealed that 48% of invasive NTHi cases and 59% of invasive Hif cases, respectively, met the criteria of severe sepsis or septic shock according to the ACCP/SCCM classification of sepsis grading. One‐fifth of invasive NTHi cases and more than one‐third of invasive Hif cases were admitted to intensive care units. Only 37% of patients with invasive non‐type b disease had evidence of immunocompromise, of which conditions related to impaired humoral immunity was the most common. The clinical burden of invasive non‐type b H. influenzae disease, measured as days of hospitalization/100 000 individuals at risk and year, increased significantly throughout the study period.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87052/1/j.1469-0691.2010.03417.x.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/87052/2/CLM_3417_sm_FigS1.pd

Acquisition of Adaptation Knowledge for Breast Cancer Treatment Decision Support

Colloque avec actes et comité de lecture. internationale.International audienceThe elaboration of a treatment in cancerology depends on the particular practice of decision protocols. These protocols are often adapted rather than used straightforwardly. This paper deals with the acquisition of the knowledge exploited during protocol adaptations. It shows that this knowledge acquisition process can be based on similarity paths, that are used for representing the matchings between decision problems (e.g., source and target problems within a case-based reasoning process)

Vitronectin binds to a specific stretch within the head region of Yersinia adhesin A and thereby modulates Yersinia enterocolitica host interaction

Complement resistance is an important virulence trait of Yersinia enterocolitica (Ye) . The predominant virulence factor expressed by Ye is Yersinia adhesin A (YadA), which enables bacterial attachment to host cells and extracellular matrix and additionally allows the acquisition of soluble serum factors. The serum glycoprotein vitronectin (Vn) acts as an inhibitory regulator of the terminal complement complex by inhibiting the lytic pore formation. Here, we show YadA-mediated direct interaction of Ye with Vn and investigated the role of this Vn binding during mouse infection in vivo. Using different Yersinia strains, we identified a short stretch in the YadA head domain of Ye O:9 E40, similar to the ‘uptake region’ of Y. pseudotuberculosis YPIII YadA, as crucial for efficient Vn binding. Using recombinant fragments of Vn, we found the C-terminal part of Vn, including heparin-binding domain 3, to be responsible for binding to YadA. Moreover, we found that Vn bound to the bacterial surface is still functionally active and thus inhibits C5b-9 formation. In a mouse infection model, we demonstrate that Vn reduces complement-mediated killing of Ye O:9 E40 and, thus, improved bacterial survival. Taken together, these findings show that YadA-mediated Vn binding influences Ye pathogenesis

Highlights of the São Paulo ISEV workshop on extracellular vesicles in cross-kingdom communication

In the past years, extracellular vesicles (EVs) have become an important field of research since EVs have been found to play a central role in biological processes. In pathogens, EVs are involved in several events during the host–pathogen interaction, including invasion, immunomodulation, and pathology as well as parasite–parasite communication. In this report, we summarised the role of EVs in infections caused by viruses, bacteria, fungi, protozoa, and helminths based on the talks and discussions carried out during the International Society for Extracellular Vesicles (ISEV) workshop held in São Paulo (November, 2016), Brazil, entitled Cross-organism Communication by Extracellular Vesicles: Hosts, Microbes and Parasites. © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.11Ysciescopu

Antibiotic-induced release of small extracellular vesicles (exosomes) with surface-associated DNA

Recently, biological roles of extracellular vesicles (which include among others exosomes, microvesicles and apoptotic bodies) have attracted substantial attention in various fields of biomedicine. Here we investigated the impact of sustained exposure of cells to the fluoroquinolone antibiotic ciprofloxacin on the released extracellular vesicles. Ciprofloxacin is widely used in humans against bacterial infections as well as in cell cultures against Mycoplasma contamination. However, ciprofloxacin is an inducer of oxidative stress and mitochondrial dysfunction of mammalian cells. Unexpectedly, here we found that ciprofloxacin induced the release of both DNA (mitochondrial and chromosomal sequences) and DNA-binding proteins on the exofacial surfaces of small extracellular vesicles referred to in this paper as exosomes. Furthermore, a label-free optical biosensor analysis revealed DNA-dependent binding of exosomes to fibronectin. DNA release on the surface of exosomes was not affected any further by cellular activation or apoptosis induction. Our results reveal for the first time that prolonged low-dose ciprofloxacin exposure leads to the release of DNA associated with the external surface of exosomes

On the role of computers in creativity-support systems

We report here on our experiences with designing computer-based creativity-support systems over several years. In particular, we present the design of three different systems incorporating different mechanisms of creativity. One of them uses an idea proposed by Rodari to stimulate imagination of the children in writing a picture-based story. The second one is aimed to model creativity in legal reasoning, and the third one uses low-level perceptual similarities to stimulate creation of novel conceptual associations in unrelated pictures.We discuss lessons learnt from these approaches, and address their implications for the question of how far creativity can be tamed by algorithmic approaches