Parachlamydia acanthamoebae Detected during a Pneumonia Outbreak in Southeastern Finland, in 2017-2018

Community-acquired pneumonia (CAP) is a common disease responsible for significant morbidity and mortality. However, the definite etiology of CAP often remains unresolved, suggesting that unknown agents of pneumonia remain to be identified. The recently discovered members of the order Chlamydiales, Chlamydia-related bacteria (CRB), are considered as possible emerging agents of CAP. Parachlamydia acanthamoebae is the most studied candidate. It survives and replicates inside free-living amoeba, which it might potentially use as a vehicle to infect animals and humans. A Mycoplasma pneumoniae outbreak was observed in Kymenlaakso region in Southeastern Finland during August 2017-January 2018. We determined the occurrence of Chlamydiales bacteria and their natural host, free-living amoeba in respiratory specimens collected during this outbreak with molecular methods. Altogether, 22/278 (7.9%) of the samples contained Chlamydiales DNA. By sequence analysis, majority of the CRBs detected were members of the Parachlamydiaceae family. Amoebal DNA was not detected within the sample material. Our study further proposes that Parachlamydiaceae could be a potential agent causing atypical CAP in children and adolescents

Spatial distributions and seasonal cycles of aerosol climate effects in India seen in a global climate-aerosol model

Climate-aerosol interactions in India are studied by employing the global climate-aerosol model ECHAM5-HAM and the GAINS inventory for anthropogenic aerosol emissions. Model validation is done for black carbon surface concentrations in Mukteshwar and for features of the monsoon circulation. Seasonal cycles and spatial distributions of radiative forcing and the temperature and rainfall responses are presented for different model setups. While total aerosol radiative forcing is strongest in the summer, anthropogenic forcing is considerably stronger in winter than in summer. Local seasonal temperature anomalies caused by aerosols are mostly negative with some exceptions, e.g., parts of northern India in March-May. Rainfall increases due to the elevated heat pump (EHP) mechanism and decreases due to solar dimming mechanisms (SDMs) and the relative strengths of these effects during different seasons and for different model setups are studied. Aerosol light absorption does increase rainfall in northern India, but effects due to solar dimming and circulation work to cancel the increase. The total aerosol effect on rainfall is negative for northern India in the months of June-August, but during March-May the effect is positive for most model setups. These differences between responses in different seasons might help converge the ongoing debate on the EHPs and SDMs. Due to the complexity of the problem and known or potential sources for error and bias, the results should be interpreted cautiously as they are completely dependent on how realistic the model is. Aerosol-rainfall correlations and anticorrelations are shown not to be a reliable sole argument for deducing causality

Caenorhabditis elegans Genomic Response to Soil Bacteria Predicts Environment-Specific Genetic Effects on Life History Traits

With the post-genomic era came a dramatic increase in high-throughput technologies, of which transcriptional profiling by microarrays was one of the most popular. One application of this technology is to identify genes that are differentially expressed in response to different environmental conditions. These experiments are constructed under the assumption that the differentially expressed genes are functionally important in the environment where they are induced. However, whether differential expression is predictive of functional importance has yet to be tested. Here we have addressed this expectation by employing Caenorhabditis elegans as a model for the interaction of native soil nematode taxa and soil bacteria. Using transcriptional profiling, we identified candidate genes regulated in response to different bacteria isolated in association with grassland nematodes or from grassland soils. Many of the regulated candidate genes are predicted to affect metabolism and innate immunity suggesting similar genes could influence nematode community dynamics in natural systems. Using mutations that inactivate 21 of the identified genes, we showed that most contribute to lifespan and/or fitness in a given bacterial environment. Although these bacteria may not be natural food sources for C. elegans, we show that changes in food source, as can occur in environmental disturbance, can have a large effect on gene expression, with important consequences for fitness. Moreover, we used regression analysis to demonstrate that for many genes the degree of differential gene expression between two bacterial environments predicted the magnitude of the effect of the loss of gene function on life history traits in those environments

Borrelia burgdorferi BBK32 Inhibits the Classical Pathway by Blocking Activation of the C1 Complement Complex

Citation: Garcia, B. L., Zhi, H., Wager, B., Hook, M., & Skare, J. T. (2016). Borrelia burgdorferi BBK32 Inhibits the Classical Pathway by Blocking Activation of the C1 Complement Complex. Plos Pathogens, 12(1), 28. doi:10.1371/journal.ppat.1005404Pathogens that traffic in blood, lymphatics, or interstitial fluids must adopt strategies to evade innate immune defenses, notably the complement system. Through recruitment of host regulators of complement to their surface, many pathogens are able to escape complement-mediated attack. The Lyme disease spirochete, Borrelia burgdorferi, produces a number of surface proteins that bind to factor H related molecules, which function as the dominant negative regulator of the alternative pathway of complement. Relatively less is known about how B. burgdorferi evades the classical pathway of complement despite the observation that some sensu lato strains are sensitive to classical pathway activation. Here we report that the borrelial lipoprotein BBK32 potently and specifically inhibits the classical pathway by binding with high affinity to the initiating C1 complex of complement. In addition, B. burgdorferi cells that produce BBK32 on their surface bind to both C1 and C1r and a serum sensitive derivative of B. burgdorferi is protected from killing via the classical pathway in a BBK32-dependent manner. Subsequent biochemical and biophysical approaches localized the anti-complement activity of BBK32 to its globular C-terminal domain. Mechanistic studies reveal that BBK32 acts by entrapping C1 in its zymogen form by binding and inhibiting the C1 subcomponent, C1r, which serves as the initiating serine protease of the classical pathway. To our knowledge this is the first report of a spirochetal protein acting as a direct inhibitor of the classical pathway and is the only example of a biomolecule capable of specifically and noncovalently inhibiting C1/C1r. By identifying a unique mode of complement evasion this study greatly enhances our understanding of how pathogens subvert and potentially manipulate host innate immune systems

Class-specific, top-down segmentation

Abstract. In this paper we present a novel class-based segmentation method, which is guided by a stored representation of the shape of objects within a general class (such as horse images). The approach is different from bottom-up segmentation methods that primarily use the continuity of grey-level, texture, and bounding contours. We show that the method leads to markedly improved segmentation results and can deal with significant variation in shape and varying backgrounds. We discuss the relative merits of class-specific and general image-based segmentation methods and suggest how they can be usefully combined. Keywords: Grouping and segmentation; Figure-ground; Top-down processing; Object classificatio

European symposium on precision medicine in allergy and airways diseases:report of the European Union parliament symposium (October 14, 2015)

On 14 October 2015, the European Academy of Allergy and Clinical Immunology (EAACI), the European Rhinologic Society (ERS) and the European Medical Association (EMA) organized a symposium in the European Parliament in Brussels on Precision Medicine in Allergy and Airways Diseases, hosted by MEP David Borrelli and with active participation of the European Respiratory Society (ERS), the European Federations of Allergy and Airways Diseases Patients Associations (EFA), the Global Allergy and Asthma European Network (Ga2len), Allergic Rhinitis and Its Impact on Asthma (ARIA) and the Respiratory Effectiveness Group (REG). MEP Sirpa Pietikainen, Chair of the European Parliament Interest Group on Allergy and Asthma, underlined the importance of the need for a better diagnostic and therapeutic approach for patients with Allergies and Chronic Airways Diseases, and encouraged a joint initiative to control the epidemic of Allergy and Asthma in Europe. The socio-economic impact of allergies and chronic airways diseases cannot be underestimated, as they represent the most frequently diagnosed chronic non-communicable diseases in the EU. Despite the fact that 30% of the total European population is nowadays suffering from allergies and asthma, more than half of these patients are deprived from adequate diagnosis and treatment. Precision Medicine represents a novel approach in medicine, embracing 4 key features: personalized care based on molecular, immunologic and functional endotyping of the disease, with participation of the patient in the decision making process of therapeutic actions, and taking into account predictive and preventive aspects of the treatment. Implementation of Precision Medicine into clinical practice may help to achieve the arrest of the Epidemic of Allergies and Chronic Airways Diseases. This report summarizes the key messages delivered during the symposium by the speakers, including the EU Commissioner for Health and Food Safety Vitenys Andriukaitis. The Commissioner underscored the need for optimal patient care in Europe, supporting joint action plans for disease prevention, patient empowerment and cost-effective treatment strategies leading to a better health status of European citizens

European symposium on the awareness of allergy: report of the promotional campaign in the European Parliament (26-28 April 2016)

From 26 to 28 of April 2016, an allergy awareness campaign was organized by the European Academy of Allergy and Clinical Immunology and the European Federation of Allergy and Airway Diseases Patients Associations in the European Parliament in Brussels, with support of the European Parliament's Interest group on Allergy and Asthma and was co-hosted by the Members of the European Parliament David Borrelli, Sirpa Pietikainen and Nessa Childers. Skin prick tests (SPTs) were performed to gain attention for the increasing prevalence of allergic airway diseases in Europe. Since more than 30% of the total European population suffers from airway allergies and asthma, reaching a higher level of awareness and elaboration of an active prevention plan is mandatory. Of the 406 individuals undergoing SPT in the European Parliament, 211 participants (52%) reported to have suffered from an allergy in the past, with allergic symptoms being present in the nose and eyes (40% and 36%, respectively), the skin (27%), lower airways (14%) and the gut (8%). Of the 381 SPT with reliable results, cutaneous hypersensitivity was found in 201 (53%) participants. Of those with positive SPT (n = 201), 70 participants (35%) were monosensitized while 131 participants (65%) were polysensitized. The positive skin reactions were found mostly for grass pollen (n = 108), followed by Dermatophagoides pteronyssinus (n = 105), Dermatophagoides farina (n = 96) and birch pollen (n = 85). Of note, 54 individuals (14% of the total tested population) without reported allergy or allergic symptoms showed a positive SPT without clinical relevance. This report summarizes the main idea and goals of the symposium: chronic airway diseases are a major and growing health problem in Europe. Therefore, a joint preventive action plan needs to be developed for a better health status of European citizen