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Background: Pregestational excessive body mass index (BMI) is linked to an increased risk for gestational diabetes mellitus (GDM), but less is known on the effect of adolescent BMI on GDM occurrence. The study aimed to investigate possible associations of adolescent BMI and changes in BMI experienced before first pregnancy, with gestational diabetes risk. Methods: This retrospective study was based on linkage of a military screening database of adolescent health status (Israel Defence Forces) including measured height and weight, with medical records (Maccabi Healthcare Services, MHS) of a state-mandated health provider. The latter covers about 25% of the Israeli population; about 90% of pregnant women undergo screening by the two-step Carpenter-Coustan method. Adolescent BMI was categorized according to Center of Disease Control and Prevention percentiles. Only first documented pregnanies were analyzed and GDM was the outcome. Findings: Of 190,905 nulliparous women, 10,265 (5.4%) developed GDM. Incidence proportions of GDM were 5.1%, 6.1%, 7.3%, and 8.9% among women with adolescent normal BMI, underweight, overweight, and obesity (p

Summary: Multiple sclerosis (MS) is an immune-mediated disease whose precise etiology is unknown. Several studies found alterations in the microbiome of individuals with MS, but the mechanism by which it may affect MS is poorly understood. Here we analyze the microbiome of 129 individuals with MS and find that they harbor distinct microbial patterns compared with controls. To study the functional consequences of these differences, we measure levels of 1,251 serum metabolites in a subgroup of subjects and unravel a distinct metabolite signature that separates affected individuals from controls nearly perfectly (AUC = 0.97). Individuals with MS are found to be depleted in butyrate-producing bacteria and in bacteria that produce indolelactate, an intermediate in generation of the potent neuroprotective antioxidant indolepropionate, which we found to be lower in their serum. We identify microbial and metabolite candidates that may contribute to MS and should be explored further for their causal role and therapeutic potential.

This paper studies information exchange in collaborative group activities involving mixed networks of people and computer agents. It introduces the concept of "nearly decomposable" decision-making problems to address the complexity of information exchange decisions in such multi-agent settings. This class of decision-making problems arise in settings which have an action structure that requires agents to reason about only a subset of their partners' actions – but otherwise allows them to act independently. The paper presents a formal model of nearly decomposable decision-making problems, NED-MDPs, and defines an approximation algorithm, NED-DECOP that computes efficient information exchange strategies. The paper shows that NED-DECOP is more efficient than prior collaborative planning algorithms for this class of problem. It presents an empirical study of the information exchange decisions made by the algorithm that investigates the extent to which people accept interruption requests from a computer agent. The context for the study is a game in which the agent can ask people for information that may benefit its individual performance and thus the groupʼs collaboration. This study revealed the key factors affecting peopleʼs perception of the benefit of interruptions in this setting. The paper also describes the use of machine learning to predict the situations in which people deviate from the strategies generated by the algorithm, using a combination of domain features and features informed by the algorithm. The methodology followed in this work could form the basis for designing agents that effectively exchange information in collaborations with people., Engineering and Applied Sciences

This paper describes a challenging plan recognition problem that arises in environments in which agents engage widely in exploratory behavior, and presents new algorithms for effective plan recognition in such settings. In exploratory domains, agentsʼ actions map onto logs of behavior that include switching between activities, extraneous actions, and mistakes. Flexible pedagogical software, such as the application considered in this paper for statistics education, is a paradigmatic example of such domains, but many other settings exhibit similar characteristics. The paper establishes the task of plan recognition in exploratory domains to be NP-hard and compares several approaches for recognizing plans in these domains, including new heuristic methods that vary the extent to which they employ backtracking, as well as a reduction to constraint-satisfaction problems. The algorithms were empirically evaluated on peopleʼs interaction with flexible, open-ended statistics education software used in schools. Data was collected from adults using the software in a lab setting as well as middle school students using the software in the classroom. The constraint satisfaction approaches were complete, but were an order of magnitude slower than the heuristic approaches. In addition, the heuristic approaches were able to perform within 4% of the constraint satisfaction approaches on student data from the classroom, which reflects the intended user population of the software. These results demonstrate that the heuristic approaches offer a good balance between performance and computation time when recognizing peopleʼs activities in the pedagogical domain of interest., Engineering and Applied Sciences

Computer systems increasingly carry out tasks in mixed networks, that is in group settings in which they interact both with other computer systems and with people. Participants in these heterogeneous human-computer groups vary in their capabilities, goals, and strategies; they may cooperate, collaborate, or compete. The presence of people in mixed networks raises challenges for the design and the evaluation of decision-making strategies for computer agents. This paper describes several new decision-making models that represent, learn and adapt to various social attributes that influence people's decision-making and presents a novel approach to evaluating such models. It identifies a range of social attributes in an open-network setting that influence people's decision-making and thus affect the performance of computer-agent strategies, and establishes the importance of learning and adaptation to the success of such strategies. The settings vary in the capabilities, goals, and strategies that people bring into their interactions. The studies deploy a configurable system called Colored Trails (CT) that generates a family of games. CT is an abstract, conceptually simple but highly versatile game in which players negotiate and exchange resources to enable them to achieve their individual or group goals. It provides a realistic analogue to multi-agent task domains, while not requiring extensive domain modeling. It is less abstract than payoff matrices, and people exhibit less strategic and more helpful behavior in CT than in the identical payoff matrix decision-making context. By not requiring extensive domain modeling, CT enables agent researchers to focus their attention on strategy design, and it provides an environment in which the influence of social factors can be better isolated and studied., Engineering and Applied Sciences

Background: Basic life support (BLS) skills are crucial not only for healthcare workers but for all lay people as well. Timely recognition of out-of-hospital cardiac arrest (OHCA) and the initiation of BLS by bystanders before the arrival of healthcare personnel may improve survival. There are several methods of spreading BLS skills and improve BLS skill retention among lay people. One of these methods can be the education of adolescent school children. The introduction of mandatory BLS education in schools was very effective in some European countries to increase the rate of bystander BLS. Methods/design: The current study aims to investigate the efficacy of a BLS training and BLS curriculum among high school children in Hungary. Moreover, the investigators would like to optimise factors influencing skill retention in this first responder group and aim to compare two types of teaching methods: feedback given by the instructor or software-based feedback on the efficacy of chest compressions during the course. This study will be an interventional, assessor blinded, individually randomised parallel group trial recruiting 360 students. BLS skill retention will be assessed at the end of the course, two months after the training and six months after training. Discussion: The current study will increase our knowledge on the methods educating BLS among high school children. The results will help us to create an effective BLS curriculum at schools.Trial registration: ClinicalTrials.gov: NCT06016153. Prospectively registered on 08/2023.

The expansion of urban areas leads to a decrease in natural habitats, resulting some species to live in urban environments. Novel environmental factors might influence their size, body condition and development stability. The environmentally induced developmental instability can be indicated by fluctuating symmetry, which means random deviations from perfect symmetry in bilaterally symmetric creatures.Our research aimed to explore the impact of various urbanization factors on snake populations within urban habitats. To achieve this, we examined how dice snake (Natrix tessellata) populations differ in their asymmetry, body condition and size in a lake characterized by highly modified lakeside habitats, intensive urban land use, and severe human disturbance. The average size, body condition and two asymmetry indices were determined for 25 dice snake populations around Lake Balaton in Hungary. The impacts of the urban environment were characterized by land use and local variables, and the risk of road kill was also estimated.Populations living in areas with a more intensive road network or near a main road showed more asymmetric traits. It is conceivable that pollutants from vehicle traffic lead to developmental disorders that manifest themselves in more asymmetric individuals. In addition, the body condition of snakes was negatively correlated with the area of the harbours, possibly due to the intensive boat traffic and human disturbance. Finally, populations living in more urbanized areas had larger body sizes meaning that despite its negative effects through pollution, anthropized areas can provide a suitable habitat for dice snakes.While urban artificial surroundings can function as suitable habitats, our results confirm that urban environmental factors have negative effects on dice snakes. Our findings indicate that the density of road networks and the proximity of roads have adverse effects on the developmental stability of urban snakes. This underscores the need to implement conservation actions to mitigate the negative effects of roads on biodiversity.

Treating social problem-solving as a construct comprised of a number of components enables us to examine patterns formed by the components. However, variable-centered research has paid little attention to exploring these patterns to date. A person-centered approach may enable us to identify distinct profiles for groups. Our study aimed to investigate whether it is possible to establish homogeneous profiles for groups based on social problem-solving factors (positive and negative orientation, rationality, impulsivity, and avoidance). Furthermore, the study sought to explore whether there is any difference among these groups regarding self-efficacy, a fundamental component of social problem-solving. We used cluster analysis to examine social problem-solving and self-efficacy among 543 Hungarian secondary school students and 277 Hungarian university students. We identified three homogeneous groups that had shared characteristics in the two age samples (optimistic–hasty; optimistic–reflective; resigned–procrastinator). Four further groups were identified among adolescents (resigned–distancer; insecure–reflective; insecure–hasty; resigned–brooder); and an additional three among young adults (optimistic–modest; tense–hasty; tense–reflective). The relationships among the social problem-solving factors and self-efficacy differed among the profiles. Taking into account the profiles explored in this study may help identify groups that need improvement, and contribute to interventions being better suited to the needs of a particular group.

ABSTRACT: This study was conducted to determine the effect of 1-stage homogenization (OSH) and 2-stage homogenization (TSH) and the addition of polysaccharides [κ-carrageenan (CR) or furcellaran (FR) at levels ranging from 0.000 to 1.000% (wt/wt)] on the physicochemical, viscoelastic, and mechanical vibration damping properties of processed cheese sauces (PCS) after 30 d of storage (6 ± 2°C). The basic chemical properties (pH, dry matter content) were similar for all tested samples. Viscoelastic measurements indicated that PCS rigidity was directly proportional to increasing CR or FR concentration and to the application of homogenization. The interactions between the application of homogenization and the concentration of polysaccharides used were also significant. Compared with OSH, TSH did not lead to any further increase in the rigidity. The preceding results were also supported by data obtained from a nondestructive method of mechanical vibration damping. No changes in water activity were observed in any PCS sample. Overall, the addition of FR or CR appeared to be highly suitable for increasing the emulsion stability of PCS. If PCS products with softer consistency are desired, then a concentration of CR/FR ≤0.250% (wt/wt) could be recommended together with OSH/TSH. For products for which a firmer PCS consistency is required, the addition of CR in concentrations of ≥0.500% (wt/wt) or FR in concentrations of ≥1.000% (wt/wt) together with OSH is recommended. Finally, as the concentration of polysaccharides increased, a darker PCS color was observed.

In the course of mining activities, large amounts of data are collected by multiple scientific disciplines. Software to assist mining engineers in planning and decision-making is, however, absent; the software used in the mining industry is not capable of a holistic approach, and therefore does not function as a data integration interface. What is required to fill this gap/to resolve this issue is an application that is platform-independent, integrates multiple types of data and does not require GIS knowledge.In this paper, a webGIS application, MaGISter-mine, is presented that can solve the problems arising during mining activities. MaGISter-mine was created as a data integrating surface that makes querying and measuring geographical data easy. The MaGISter-mine application is able to handle photogrammetry models and laser-scanned point clouds, while distance, area and volume can also be easily calculated. The software can draw 2D profiles from 3D files. Time- and space-dependent changes between two surveys can be analysed, too. Geological strata can be edited, and new surfaces can be generated by kriging interpolation.During the development of the webGIS application, mostly open-source software and libraries were used. The spatial database consists of the PostgreSQL relational database management system and its extension, called PostGIS. To perfect accessibility on the client side, GeoServer with Apache Tomcat and Apache webserver were employed. The webGIS application was developed using OpenLayers, three.js and Potree, written in PHP, SQL, HTML, CSS and JavaScript languages.

Summary: The role of MDC1 in the DNA damage response has been extensively studied; however, its impact on other cellular processes is not well understood. Here, we describe the role of MDC1 in transcription as a regulator of RNA polymerase II (RNAPII). Depletion of MDC1 causes a genome-wide reduction in the abundance of actively engaged RNAPII elongation complexes throughout the gene body of protein-encoding genes under unperturbed conditions. Decreased engaged RNAPII subsequently alters the assembly of the spliceosome complex on chromatin, leading to changes in pre-mRNA splicing. Mechanistically, the S/TQ domain of MDC1 modulates RNAPII-mediated transcription. Upon genotoxic stress, MDC1 promotes the abundance of engaged RNAPII complexes at DNA breaks, thereby stimulating nascent transcription at the damaged sites. Of clinical relevance, cancer cells lacking MDC1 display hypersensitivity to RNAPII inhibitors. Overall, we unveil a role of MDC1 in RNAPII-mediated transcription with potential implications for cancer treatment.

The distribution of the high concentrations of arsenic (As) and fluoride (F-) in groundwater on a Pan-European scale could be explained by the geological European context (lithology and structural faults). To test this hypothesis, seventeen countries and eighteen geological survey organizations (GSOs) have participated in the dataset. The methodology has used the HydroGeoToxicity (HGT) and the Baseline Concentration (BLC) index. The results prove that most of the waters considered in this study are in good conditions for drinking water consumption, in terms of As and/or F- content. A low proportion of the analysed samples present HGT≥ 1 levels (4% and 7% for As and F-, respectively). The spatial distribution of the highest As and/or F- concentrations (via BLC values) has been analysed using GIS tools. The highest values are identified associated with fissured hard rock outcrops (crystalline rocks) or Cenozoic sedimentary zones, where basement fractures seems to have an obvious control on the distribution of maximum concentrations of these elements in groundwaters.

Pikeperch Sander lucioperca is a species of increasing presence in recirculation aquaculture system and the vast majority of thus far research was dedicated to its indoor farming. Concerning the present pond infrastructure in Central and East Europe, it is of interest to evaluate the intensive pond-connected system for pikeperch rearing. Therefore, the present study evaluated the grow-out performance in recirculation aquaculture system (RAS) and in-pond-raceway (IPR) in triplicated tanks. A 16-week trial with 1-year-old pikeperch (mean weight 215.7 ± 8.1 g RAS and 217.7 ± 2.6 g IPR) was conducted from June to October evaluating both culture and welfare parameters. Significantly higher final mean weight (443.1 ± 17.5 vs 400.6 ± 13.2) and lower feed conversion (2.1 ± 0.1 vs 3.0 ± 0.1) was obtained in fish reared in IPR. Cortisol levels were overall higher in the RAS group throughout the trial being significantly higher at the first and last sampling. Elevated lysozyme levels were found in IPR in the first half of the trial, while further on they were higher in RAS being significantly higher compared to IPR in middle sampling. Thus, both in terms of culture performance and fish welfare, IPR proves aptness for pikeperch rearing. This study presents the first insight into the suitability of pond-connected intensive rearing of pikeperch describing IPR as a promising system for final grow-out during the growing season. More comprehensive studies in terms of stocking densities and growing period are required to explore the full potential of pikeperch outdoor farming.

ABSTRACT: The effect of various cooking methods (roasting, broiling, grilling, frying, and stewing) on cooking loss (CL) and textural and sensory properties of selected chicken (breast fillet, thigh, and thigh fillet) and turkey (breast fillet, thigh) cuts in relation to the applied apparatus was evaluated. Diverse results were recorded according to the method, the type of poultry meat, and the cut of poultry meat. Additionally, CL and shear force (SF) values in all examined samples were influenced by the culinary technique, the type of poultry meat, and the poultry meat cut. The lowest CL and shear SF values were reported when the samples were treated using a method with higher heating rates and/or temperatures and shorter cooking times. Additionally, lower values of CL and SF were obtained for chicken meat compared to turkey meat (thighs). In general, the applied culinary technique affected the sensory properties of the samples tested. High sensory scores were recorded for grilled chicken breast fillets and fried turkey breast fillets (irrespective of the applied apparatus). On the whole, it could be stated that culinary techniques at high temperature requiring shorter times (such as frying, grilling, and roasting) were evaluated to be more effective (in terms of CL and SF).

Cerebral palsy (CP) is a well-researched area of medical science, health science and special education. The growing number of publications every year makes difficult to monitor the progress of this research domain, therefore there is a broad interest for conducting systematic reviews and meta-analyses of interventions in international peer-reviewed scientific journals.Our goal is to analyze the scientific activity of authors who published systematic reviews and meta-analyses of CP intervention studies. To identify the active researchers, institutions, and countries, we used scientometric and bibliometric indicators that assess their productivity, collaborations, and the citations (utilization/usefulness of their studies), also paying attention to the institutional background and the network structure of national and international collaboration.We used Scopus to search for articles and included systematic reviews and meta-analyses of intervention studies, a total of 180 works, in our sample.Our results showed active and large communities of prolific authors and groups of authors with diverse institutional background. Most institutions are universities, hospitals, but we found various other organizations among them. Most of the universities are leading educational institutions according to international rankings; some of them are among the top-ranking ones. In geographical terms, the North American, Australian, and European regions are the most active and most interconnected ones. We assume organizations other than scientific collaboration networks also play a major role in the productivity and dissemination of scientific knowledge in this research area. As an example, we could mention the network, including the US, Australian and European registers. Authors living and working in the Far East, the Middle East or in South America also started to publish relevant articles in the 2010s. The research network structuring scientific knowledge in this area is flourishing.

Roads threaten animal species through habitat loss, fragmentation and degradation, and direct mortality. It is crucial to understand how species respond to linear infrastructure for effective conservation of animal communities in fragmented landscapes. We assessed relationships between amphibian abundance and roads/ railways and habitat fragmentation. We examined whether the combined effects of habitat loss and roads or railways (accessible habitat) was a better predictor of amphibian abundance than (1) the total amount of habitat surrounding ponds, (2) distance to a highway or railway, or (3) surrounding road cover. Aquatic surveys for amphibian larvae were conducted at 30 freshwater ponds over the breeding season in a mixed peri-urban/ agricultural landscape in Hungary. Landscape variables were quantified within a 1000-m radius surrounding ponds and habitat variables were measured at the local (pond) scale. The larvae of seven amphibian species were detected. There were strong relationships between the abundance of amphibian larvae and the distance to a highway and the proportion of road cover within 1000 m of ponds. Relationships with accessible habitat and total habitat amount were uncertain, while there were no clear relationships with a major railway. Larval abundance increased with pond size, but there were mixed relationships with the presence of fish. Our results suggest that road effects were having a stronger impact on amphibian abundance than the combined effects of roads and habitat amount in the study area. Highways appeared to be negatively impacting amphibian communities within a wide road-effect zone up to 1 km from ponds. However, our results were obtained from a single-season snap-shot study and multi-season surveys are likely required to reduce uncertainty in the model predictions. Our analysis suggests that road mitigation projects for amphibians should create large ponds in areas with no highways and low road density, and with connectivity to surrounding habitats.

The recreational use of water bodies presents new challenges and pressures on lake ecosystems. We focused on how recreational beaches influence the shoreline biodiversity of Lake Balaton, Hungary. Taking into account the establishment of beaches, we examined natural reed vegetated shorelines (representing natural situation), open areas (representing areas, where reed has been removed), as well as beaches. We assessed the abiotic parameters as well as the chironomid assemblages of these habitats. We found that the transformation of reeds through open habitats to beaches is associated with multiple changes in environmental properties and with a decrease in habitat heterogeneity. We observed that the transformation of reeds to beaches caused an 18% reduction in chironomid taxa richness and a moderate drop in their abundance. This reduction can be explained by the removal of reeds, because this action transforms a productive system to an unproductive one, and by the assumed dependence of chironomid richness and abundance to the organic-matter content of the sediment. Our analyses showed that the composition of chironomids was sensitive to the transformation of the habitats, and to the natural differences in the northern and southern shorelines of the lake. These findings suggest that the establishment and use of recreational beaches had a negative effect on local biodiversity. Although beaches can promote diversified societal and economic benefits, our results show that they can also generate conservation issues related to biodiversity loss. Consequently, action plans focusing on the maintenance and the establishment of recreational beaches should carefully consider both economic and conservation aspects.

Pott's puffy tumour is a life threatening complication of infectious sinusitis which is the osteomyelitis of the frontal bone with associated subperiosteal abscess causing swelling and oedema over the forehead and scalp.Here we present a case a 70 year old male with a rare infectious complication of untreated sinusitis called Pott's puffy tumour which was diagnosed due to high clinical suspicion and confirmed with CT imaging.This case highlights the need to recognize and easily prevent this fatal complication of a seemingly benign infection like bacterial sinusitis. Unfortunately, if it does occur, clinicians can avoid missing the diagnosis by upholding a high clinical suspicion in the setting of known risk factors and must look for underlying causes both medical and psychosocial. Keywords: Pott's tumour, Forehead abscess, Frontal sinusitis, Endoscopic endonasal surgery

Increased fMRI food cue reactivity in obesity, i.e. higher responses to high- vs. low-calorie food images, is a promising marker of the dysregulated brain reward system underlying enhanced susceptibility to obesogenic environmental cues. Recently, it has also been shown that weight loss interventions might affect fMRI food cue reactivity and that there is a close association between the alteration of cue reactivity and the outcome of the intervention. Here we tested whether fMRI food cue reactivity could be used as a marker of diet-induced early changes of neural processing in the striatum that are predictive of the outcome of the weight loss intervention. To this end we investigated the relationship between food cue reactivity in the striatum measured one month after the onset of the weight loss program and weight changes obtained at the end of the six-month intervention. We observed a significant correlation between BMI change measured after six months and early alterations of fMRI food cue reactivity in the striatum, including the bilateral putamen, right pallidum, and left caudate. Our findings provide evidence for diet-induced early alterations of fMRI food cue reactivity in the striatum that can predict the outcome of the weight loss intervention. Keywords: Obesity, Reward system, Striatum, Food-cue images, Body mass index

A natural fat-soluble thiamine derivative, namely N-[(4-amino-2-methylpyrimidin-5-yl)methyl]-N-[(2E)-5-hydroxy-3-(prop-2-en-1-yldisulfanyl)pent-2-en-2-yl]formamide (allithiamine) has been identified only in garlic (Allium sativum) until now. Hungarian red sweet pepper (Capsicum annuum) was found as a new source of allithiamine. Extraction procedure and analytical method were developed for the isolation of allithiamine and a chemical synthesis of the compound was also developed. First solid-liquid extraction was performed with 96 % ethanol to isolate allithiamine from pepper seeds. Thereafter, solid phase extraction was applied from ethanolic extract using C18 cartridge to concentrate and purify samples for further analysis. The structure of the synthesized and the isolated compounds was verified by reverse phase HPLC, HPLC-MS, MALD-TOF MS and NMR. Furthermore, effect of allithiamine was investigated on streptozotocin-induced diabetic mice with neuropathy. The results show that neuropathic pain sensation is improved by allithiamine treatment similarly to benfothiamine.

The lectin pathway of complement is part of the innate immune system. The complement-activating pattern-recognition molecules (for which we suggest the abbreviation CAPREMs) mannan-binding lectin (MBL) and the three ficolins (H-, L- and M-ficolin) circulate in complexes with MBL-associated serine proteases (MASP-1, -2 and -3) and two additional proteins (MAp19 and MAp44, also termed sMAP and MAP-1, respectively). When MBL or ficolins recognize a microorganism or altered self components, activation of the MASPs ensues, leading to the activation of the complement system. MASP-1, MASP-3 and MAp44 are all three encoded by the MASP1 gene. MASP-1 and -3 share five domains (constituting the so-called A-chain), but have unique protease domains (B-chains). MAp44 shares the first four domains with MASP-1 and MASP-3, followed by 17 unique C-terminal amino acid residues. Thus, assays for the protease domain of MASP-3 and for the 17 C-terminal amino acids of MAp44 are required to measure these proteins specifically and here we present such assays for MASP-3 and MAp44. MASP-3 was captured with a monoclonal antibody (5F5) reacting with a common domain of the three proteins (CCP1) and the assay was developed with a monoclonal antibody (38.12.3) specific for the C-terminal part of the MASP-3 protease domain. MAp44 was captured with a monoclonal antibody (2D5) reacting with the C-terminus of MAp44 followed by assay development with a monoclonal anti-CCP1 antibody (4H2). Using Superose 6 gel permeation chromatography of serum, MASP-3 and MAp44 were found in complexes, which eluted in positions corresponding to 600-800 kDa and 500-700 kDa, respectively. The level of MASP-3 in donor sera (N=200) was log-normally distributed with a median value of 5.0 μg/ml (range: 1.8-10.6 μg/ml), and the corresponding value for MAp44, also log-normally distributed, was 1.7 μg/ml (range: 0.8-3.2 μg/ml). For MASP-3, the inter-assay coefficients of variation of low, intermediate and high level internal controls were 4.9%, 6.9% and 3.9% (N=12). For MAp44, the corresponding inter-assay CVs were 7.6%, 6.2%, and 7.0% (N=12). MASP-3 levels were low at birth and reached adult levels within the first 6 months, whereas MAp44 levels fell slightly during the first 6 months. Concomitant with the acute phase response in patients undergoing major surgery, levels of both proteins fell slightly over 1-2 days, but whereas MASP-3 recovered to baseline values over another 2 days, MAp44 only reached baseline values at around day 30. Thus, neither of the two proteins behaves as a classical acute phase protein., (Copyright © 2010 Elsevier B.V. All rights reserved.)

C1r, C1s, MBL-associated serine protease (MASP)-1, MASP-2 and MASP-3 are mosaic serine proteases of the classical and lectin pathways of complement. They form a family of enzymes with identical domain organization and similar overall structure, but with different enzymatic properties. MASP-2 of the lectin pathway can autoactivate and cleave C4 and C2 components. In the classical pathway two enzymes mediate these functions: C1r autoactivates and activates C1s, while C1s cleaves C4 and C2. The substrate specificity and the biological function of MASP-1 and MASP-3 have not yet been completely resolved. MASP-1 can autoactivate and the activated MASP-1 has more relaxed substrate specificity than the other members of the family. It was demonstrated that MASP-1 can specifically cleave C2, C3 and fibrinogen, but the physiological relevance of these findings has to be proved. We do not know how MASP-3 becomes activated and its biological function is also not clear. In this review, we will summarize current knowledge about the structure and function of these proteases. Special emphasis will be laid on the specificity, autoactivation and evolution of these enzymes.

The flagellum-specific export system is a specialized type III export machinery. Terminally truncated fragments of flagellin (FliC) were used to identify the secretion signal in the main component of flagellar filaments. The first 13 residues were not essential for export, but removal of 29 or more residues destroyed export ability. When an 8kDa human protein domain was fused to various N-terminal fragments of FliC, the 26-47 sequence alone was sufficient to mediate secretion of this protein module through the flagellum specific export pathway. Neither half of this segment was enough to direct export of the attached protein domain. Our results demonstrate that the 22-residue long 26-47 segment within the disordered N-terminal region of Salmonella flagellin contains the recognition signal for the flagellar export machinery.

A family of serine proteases mediates the proteolytic cascades of several defense mechanisms in vertebrates, such as the complement system, blood coagulation and fibrinolysis. These proteases usually form large complexes with other glycoproteins. Their common features are their modular structures and restricted substrate specificities. The lectin pathway of complement, where mannose-binding lectin (MBL) recognizes the carbohydrate structures on pathogens, is activated by mannose-binding lectin-associated serine protease-2 (MASP-2). We present the 2.25A resolution structure of the catalytic fragment of MASP-2 encompassing the second complement control protein module (CCP2) and the serine protease (SP) domain. The CCP2 module stabilizes the structure of the SP domain as demonstrated by differential scanning calorimetry measurements. The asymmetric unit contains two molecules with different CCP-SP domain orientations, reflecting increased modular flexibility at the CCP2/SP joint. This flexibility may partly explain the ability of the MASP-2 dimer to perform all of its functions alone, whereas the same functions are mediated by the much larger C1r2-C1s2 tetramer in the C1 complex of the classical pathway. The main scaffold of the MASP-2 SP domain is chymotrypsin-like. Eight surface loops determine the S1 and other subsite specificities. Surprisingly, some surface loops of MASP-2, e.g. loop 1 and loop 2, which form the S1 pocket are similar to those of trypsin, and show significant differences if compared with those of C1s, indicating that the nearly identical substrate specificities of C1s and MASP-2 are realized through different sets of enzyme-substrate interactions.

The Mannose-binding lectin-associated serine proteases (MASPs) have been the subject of intensive research particularly over the past 10 years. First one, then two, and currently 3 MASPs have been characterized. Initially it was thought likely that the MBL + MASPs system would resemble very closely the C1 complex of the complement classical pathway, and that MASP1 and MASP2 would have similar activities to their classical pathway homologues C1r and C1s. MASP2 does certainly have similar activities to C1s, but MASP1 does not have the activities of either C1r or C1s. MASP1 has been thought to act on the complement system by cleaving C3 directly, but work with recombinant and purified native MASP1 shows that direct C3 cleavage by this protease is very slow, and may not be biologically significant. MASP1 and MASP2 appear not to have such a narrow specificity as C1r and C1s, and may have significant substrates other than complement proteins. As an example, MASP1 does cleave fibrinogen, releasing fibrinopeptide B (a chemotactic factor) and also cleaves and activates plasma transglutaminase (Factor XIII). These reactions are also relevant to defence against microorganisms, and may represent a biologically significant action of MASP1.

C1s is the modular serine protease, which executes the catalytic function of the C1 complex: the cleavage of C4 and C2. Like other complement serine proteases C1s has restricted substrate specificity and it is engaged into specific interactions with other subcomponents of the complement system. There has been a rapid progress in determining the 3D structure of complement serine proteases and in revealing the role of the individual domains in the protein-protein interaction properties. In this review we summarize recent findings on the structure of C1s, and on the mechanism of action of this protease. The results obtained by genetic engineering, physico-chemical and functional studies are reviewed. The physiological relevance of the proteolytic action of C1s and its possible implications in health and disease will also be discussed.

Our protein engineering studies on human C1r and C1s revealed important characteristics of the individual domains of these multidomain serine-proteases, and supplied evidence about the cooperation of the domains to create binding sites, and to control the activation process. We expressed the recombinant subcomponents in the baculovirus-insect cell system and checked the biological activity. Deletions and point mutants of C1r were constructed and C1r-C1s chimeras were also produced. Our deletion mutants demonstrated that the N-terminal CUB domain and the EGF-like domain of C1r together are responsible for the calcium dependent C1r-C1s interaction. It seems very likely that these two modules form the calcium-binding site of the C1r alpha-fragment and participate in the tetramer formation. The deletion mutants also demonstrated that the N-terminal region of the C1r molecule contains essential elements involved in the control of activation of the serine-protease module. The substrate specificity of the serine-protease is also determined by the five N-terminal noncatalytic domain of C1r/C1s chimera, which contains the catalytic domain of C1s preceded by the N-terminal region of C1r, could replace the C1r in the hemolytically active C1 complex. The C1s/C1r chimera, in which the alpha-fragment of the C1r was replaced for that of the C1s exibits both C1r- and C1s-like characteristics. We stabilized the zymogen form of human C1r by mutating the Arg(463)-Ile(464) bond. Using our stable zymogen C1r we showed that one active C1r in the C1 complex is sufficient for the full activity of the entire complex. Further experiment with this mutant could provide us with important information about the structure of the C1 complex.

Spodoptera frugiperda cells are the hosts of wild type and recombinant virus in the baculovirus insect cell expression system. The expression of the foreign gene could be enhanced by the addition of ecdysteroids and increased amount of recombinant protein was secreted into the medium. The time and concentration dependence of this effect was followed in the case of 20-hydroxyecdysone-, makisterone and ecdysone. 20-hydroxyecdysone proved to be the most efficient, producing a three fold increase in the level of recombinant protein secreted into the medium, as it was measured by ELISA. This effect was also confirmed by tracing the L-(35S)methionine incorporation into the gene product. Makisterone was also effective in stimulation, while ecdysone proved to be ineffective.

The Fc fragment of human IgG1 can be trapped in a stable intermediate state during thermal denaturation. In this conformation the molecule is compact with a native-like secondary structure, however, the tertiary structure is perturbed as revealed by intrinsic fluorescence measurements, the near-UV CD spectra and by mapping of antigenic sites with monoclonal antibodies. Similar phenomena were recently described for a few globular proteins of small size, and termed 'the molten globule' state. Our observation is a unique example of this phenomenon for a four domain protein.