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BACKGROUND: It has been suggested that noise exposure increases the risk of hypertension. Road traffic is the dominant source of community noise exposure. OBJECTIVE: To study the association between exposure to residential road traffic noise and hypertension in an urban municipality. METHODS: The study population comprised randomly selected subjects aged 19-80 years. A postal questionnaire provided information on individual characteristics, including diagnosis of hypertension. The response rate was 77%, resulting in a study population of 667 subjects. The outdoor equivalent traffic noise level (Leq 24 h) at the residence of each individual was determined using noise-dispersion models and manual noise assessments. The individual noise exposure was classified in units of 5 dB(A), from <45 dB(A) to >65 dB(A). RESULTS: The odds ratio (OR) for hypertension adjusted for age, smoking, occupational status and house type was 1.38 (95% confidence interval (CI) 1.06 to 1.80) per 5 dB(A) increase in noise exposure. The association seemed stronger among women (OR 1.71; 95% CI 1.17 to 2.50) and among those who had lived at the address for >10 years (OR 1.93; 95% CI 1.29 to 2.83). Analyses of categorical exposure variables suggested an exposure-response relationship. The strongest association between exposure to traffic noise and hypertension was found among those with the least expected misclassification of true individual exposure, as indicated by not having triple-glazed windows, living in an old house and having the bedroom window facing a street (OR 2.47; 95% CI 1.38 to 4.43). CONCLUSION: The results of our study suggest an association between exposure to residential road traffic noise and hypertension. [ABSTRACT FROM AUTHOR]

Abstract Background We aim to propose interactions between the parathyroid hormone-2 receptor (PTH2R) and its ligand the tuberoinfundibular peptide of 39 residues (TIP39) by constructing a homology model of their complex. The two related peptides parathyroid hormone (PTH) and parathyroid hormone related protein (PTHrP) are compared with the complex to examine their interactions. Findings In the model, the hydrophobic N-terminus of TIP39 is buried in a hydrophobic part of the central cavity between helices 3 and 7. Comparison of the peptide sequences indicates that the main discriminator between the agonistic peptides TIP39 and PTH and the inactive PTHrP is a tryptophan-phenylalanine replacement. The model indicates that the smaller phenylalanine in PTHrP does not completely occupy the binding site of the larger tryptophan residue in the other peptides. As only TIP39 causes internalisation of the receptor and the primary difference being an aspartic acid in position 7 of TIP39 that interacts with histidine 396 in the receptor, versus isoleucine/histidine residues in the related hormones, this might be a trigger interaction for the events that cause internalisation. Conclusions A model is constructed for the complex and a trigger interaction for full agonistic activation between aspartic acid 7 of TIP39 and histidine 396 in the receptor is proposed.

Rare diseases are, despite their name, collectively common and millions of people are affected daily of conditions where treatment often is unavailable. Sulfatases are a large family of activating enzymes related to several of these diseases. Heritable genetic variations in sulfatases may lead to impaired activity and a reduced macromolecular breakdown within the lysosome, with several severe and lethal conditions as a consequence. While therapeutic options are scarce, treatment for some sulfatase deficiencies by recombinant enzyme replacement are available. The recombinant production of such sulfatases suffers greatly from both low product activity and yield, further limiting accessibility for patient groups. To mitigate the low product activity, we have investigated cellular properties through computational evaluation of cultures with varying media conditions and comparison of two CHO clones with different levels of one active sulfatase variant. Transcriptome analysis identified 18 genes in secretory pathways correlating with increased sulfatase production. Experimental validation by upregulation of a set of three key genes improved the specific enzymatic activity at varying degree up to 150-fold in another sulfatase variant, broadcasting general production benefits. We also identified a correlation between product mRNA levels and sulfatase activity that generated an increase in sulfatase activity when expressed with a weaker promoter. Furthermore, we suggest that our proposed workflow for resolving bottlenecks in cellular machineries, to be useful for improvements of cell factories for other biologics as well., Competing Interests: Declaration of competing interest Johan Rockberg reports equipment, drugs, or supplies was provided by Swedish Orphan Biovitrum AB. Johanna Rodhe reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Monica Andersson reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Dominik Possner reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Chao Su reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Joakim Nilsson reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Jeanette Vestin reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Johan Forsberg reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Erik Nordling reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. Anna Sandegren reports a relationship with Swedish Orphan Biovitrum AB that includes: employment. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

To utilize modern tools to assess depressive and anxiety symptoms, wellbeing and life conditions in pregnant women during the first two waves of the COVID-19 pandemic in Sweden. Pregnant women (n = 1577) were recruited through the mobile application Mom2B. Symptoms of depression, anxiety and wellbeing were assessed during January 2020-February 2021. Movement data was collected using the phone's sensor. Data on Google search volumes for "Corona" and Covid-related deaths were obtained. Qualitative analysis of free text responses regarding maternity care was performed. Two peaks were seen for depressive symptoms, corresponding to the two waves. Higher prevalence of anxiety was only noted during the first wave. A moderating effect of the two waves in the association of depression, anxiety, and well-being with Covid deaths was noted; positive associations during the first wave and attenuated or became negative during the second wave. Throughout, women reported on cancelled healthcare appointments and worry about partners not being allowed in hospital. The association of mental health outcomes with relevant covariates may vary during the different phases in a pandemic, possibly due to adaptation strategies on a personal and societal/healthcare level. Digital phenotyping can help healthcare providers and governmental bodies to in real time monitor high-risk groups during crises, and to adjust the support offered., (© 2022. The Author(s).)

Inflammasomes and the interleukin (IL)-1 family of cytokines are key mediators of both inflammation and immunothrombosis. Inflammasomes are responsible for the release of the pro-inflammatory cytokines IL-1β and IL-18, as well as releasing tissue factor (TF), a pivotal initiator of the extrinsic coagulation cascade. Uncontrolled production of inflammatory cytokines results in what is known as a "cytokine storm" leading to hyperinflammatory disease. Cytokine storms can complicate a variety of diseases and results in hypercytokinemia, coagulopathies, tissue damage, multiorgan failure, and death. Patients presenting with cytokine storm syndromes have a high mortality rate, driven in part by disseminated intravascular coagulation (DIC). While our knowledge on the factors propagating cytokine storms is increasing, how cytokine storm influences DIC remains unknown, and therefore treatments for diseases, where these aspects are a key feature are limited, with most targeting specific cytokines. Currently, no therapies target the immunothrombosis aspect of hyperinflammatory syndromes. Here we discuss how targeting the inflammasome and pyroptosis may be a novel therapeutic strategy for the treatment of hyperinflammation and its associated pathologies., Competing Interests: E.N. and C.K. are employees of SOBI., (© The Author(s) 2022. Published by Oxford University Press on behalf of the British Society for Immunology.)

The proinflammatory cytokine Interleukin-1 (IL-1), with its two isoforms α and β, has important roles in multiple pathogenic processes in the central nervous system. The present study aimed to evaluate and compare the blood-to-brain distribution of anakinra (IL-1 receptor antagonist), bermekimab (IL-1α antagonist) and canakinumab (IL-1β antagonist). A human in vitro model of the blood-brain barrier derived from human umbilical cord blood stem cells was used, where isolated CD34 + cells co-cultured with bovine pericytes were matured into polarized brain-like endothelial cells. Transport rates of the three test items were evaluated after 180 ​min incubation at concentrations 50, 250 and 1250 ​nM in a transwell system. We report herein that anakinra passes the human brain-like endothelial monolayer at a 4-7-fold higher rate than the monoclonal antibodies tested. Both antibodies had similar transport rates at all concentrations. No dose-dependent effects in transport rates were observed, nor any saturation effects at supraphysiological concentrations. The larger propensity of anakinra to pass this model of the human blood-brain barrier supports existing data and confirms that anakinra can reach the brain compartment at clinically relevant concentrations. As anakinra inhibits the actions of both IL-1α and IL-1β, it blocks all effects of IL-1 downstream signaling. The results herein further add to the growing body of evidence of the potential utility of anakinra to treat neuroinflammatory disorders., Competing Interests: CK, LL, EN are current employees of Swedish Orphan Biovitrum AB (publ), EOS is a former employee and current consultant contracted by Swedish Orphan Biovitrum AB (publ), MÅ is a former employee of Swedish Orphan Biovitrum AB (publ). CK, LL, EN, EOS are shareholders of Swedish Orphan Biovitrum AB (publ). MC and FG have been contracted for performing the study at LBHE (UA) by Swedish Orphan Biovitrum AB (publ)., (© 2021 The Author(s).)

We show the successful application of ancestral sequence reconstruction to enhance the activity of iduronate-2-sulfatase (IDS), thereby increasing its therapeutic potential for the treatment of Hunter syndrome-a lysosomal storage disease caused by impaired function of IDS. Current treatment, enzyme replacement therapy with recombinant human IDS, does not alleviate all symptoms, and an unmet medical need remains. We reconstructed putative ancestral sequences of mammalian IDS and compared them with extant IDS. Some ancestral variants displayed up to 2-fold higher activity than human IDS in in vitro assays and cleared more substrate in ex vivo experiments in patient fibroblasts. This could potentially allow for lower dosage or enhanced therapeutic effect in enzyme replacement therapy, thereby improving treatment outcomes and cost efficiency, as well as reducing treatment burden. In summary, we showed that ancestral sequence reconstruction can be applied to lysosomal enzymes that function in concert with modern enzymes and receptors in cells., Competing Interests: Anna Sandegren, Tommy Andersson, Jenny Blomqvist, Åsa Makower, Dominik Possner, Chao Su, Agneta Tjernberg, Ulrica Westermark, and Stefan Svensson Gelius were employed by Swedish Orphan Biovitrum AB at the time the study was conducted. Natalie Hendrikse was funded by the 10.13039/501100001729Swedish Foundation for Strategic Research and was jointly employed by the 10.13039/501100004270Royal Institute of Technology and 10.13039/501100012112Swedish Orphan Biovitrum AB. Erik Nordling is currently employed by Swedish Orphan Biovitrum AB. All authors declare no competing interests., (© 2021 The Author(s).)

Phenylalanine/tyrosine ammonia-lyases (PAL/TALs) have been approved by the FDA for treatment of phenylketonuria and may harbour potential for complementary treatment of hereditary tyrosinemia Type I. Herein, we explore ancestral sequence reconstruction as an enzyme engineering tool to enhance the therapeutic potential of PAL/TALs. We reconstructed putative ancestors from fungi and compared their catalytic activity and stability to two modern fungal PAL/TALs. Surprisingly, most putative ancestors could be expressed as functional tetramers in Escherichia coli and thus retained their ability to oligomerize. All ancestral enzymes displayed increased thermostability compared to both modern enzymes, however, the increase in thermostability was accompanied by a loss in catalytic turnover. One reconstructed ancestral enzyme in particular could be interesting for further drug development, as its ratio of specific activities is more favourable towards tyrosine and it is more thermostable than both modern enzymes. Moreover, long-term stability assessment showed that this variant retained substantially more activity after prolonged incubation at 25 °C and 37 °C, as well as an increased resistance to incubation at 60 °C. Both of these factors are indicative of an extended shelf-life of biopharmaceuticals. We believe that ancestral sequence reconstruction has potential for enhancing the properties of enzyme therapeutics, especially with respect to stability. This work further illustrates that resurrection of putative ancestral oligomeric proteins is feasible and provides insight into the extent of conservation of a functional oligomerization surface area from ancestor to modern enzyme.

Bacterial diterpene cyclases are receiving increasing attention in biocatalysis and synthetic biology for the sustainable generation of complex multicyclic building blocks. Herein, we explore the potential of ancestral sequence reconstruction (ASR) to generate remodeled cyclases with enhanced stability, activity, and promiscuity. Putative ancestors of spiroviolene synthase, a bacterial class I diterpene cyclase, display an increased yield of soluble protein of up to fourfold upon expression in the model organism Escherichia coli. Two of the resurrected enzymes, with an estimated age of approximately 1.7 million years, display an upward shift in thermostability of 7-13 °C. Ancestral spiroviolene synthases catalyze cyclization of the natural C 20 -substrate geranylgeranyl diphosphate (GGPP) and also accept C 15 farnesyl diphosphate (FPP), which is not converted by the extant enzyme. In contrast, the consensus sequence generated from the corresponding multiple sequence alignment was found to be inactive toward both substrates. Mutation of a nonconserved position within the aspartate-rich motif of the reconstructed ancestral cyclases was associated with modest effects on activity and relative substrate specificity (i.e., k cat /K M for GGPP over k cat /K M for FPP). Kinetic analyses performed at different temperatures reveal a loss of substrate saturation, when going from the ancestor with highest thermostability to the modern enzyme. The kinetics data also illustrate how an increase in temperature optimum of biocatalysis is reflected in altered entropy and enthalpy of activation. Our findings further highlight the potential and limitations of applying ASR to biosynthetic machineries in secondary metabolism., (© The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

The complement component 5 (C5)-binding antibody eculizumab is used to treat patients with paroxysmal nocturnal hemoglobinuria (PNH) and atypical haemolytic uremic syndrome (aHUS). As recently reported there is a need for a precise classification of eculizumab responsive patients to allow for a safe and cost-effective treatment. To allow for such stratification, knowledge of the precise binding site of the drug on its target is crucial. Using a structural epitope mapping strategy based on bacterial surface display, flow cytometric sorting and validation via haemolytic activity testing, we identified six residues essential for binding of eculizumab to C5. This epitope co-localizes with the contact area recently identified by crystallography and includes positions in C5 mutated in non-responders. The identified epitope also includes residue W917, which is unique for human C5 and explains the observed lack of cross-reactivity for eculizumab with other primates. We could demonstrate that Ornithodorus moubata complement inhibitor (OmCI), in contrast to eculizumab, maintained anti-haemolytic function for mutations in any of the six epitope residues, thus representing a possible alternative treatment for patients non-responsive to eculizumab. The method for stratification of patients described here allows for precision medicine and should be applicable to several other diseases and therapeutics.

Amyloidosis is characterized by misfolding of proteins. The clinical gastrointestinal manifestations of amyloidosis may mimic other disease, such as inflammatory bowel disease or colonic cancer. As these patients have a high risk for bleeding and poor wound healing following surgery it is important to diagnose them correctly and do a careful preoperative assessment. The most common form of colonic amyloidosis is caused by Serum Amyloid A (SAA), an acute phase protein of unknown function. It is expressed in response to inflammation and the increased levels may lead to amyloidosis. The main treatment is to suppress the acute phase response and thereby reduce production of SAA. As no structure for SAA is available we aim to perform an in silico assessment of its structural and fibrillation properties. In the paper we propose an ab initio model of the structure of SAA, which consists of a five membered helical bundle with a fold related to the tetratricopeptide repeat domain. As there are uncertainties relating to the packing of the helices, each helical region is subjected to triplicate molecular dynamics simulations to assess the integrity of the structural region. The first helix, stretching from residues 1 to 13, is the least stable according to the simulations; almost all of the helical conformation is lost during the 10 ns simulations, whereas the other helices maintain portions that remain in an helical conformation in at least 80% of the simulations. All helices are also subjected to a single 100 ns simulation to investigate how the secondary structure develops over time. In them helix 1 adopts a β-hairpin structure similar to other fibril forming proteins. The β-hairpin can in turn multimerise and form a mature fibril structure. The mechanism behind the conformational transition appears to be driven by interactions of side chains of charged residues, particularly Arginine 1. It exchanges interaction partners in the simulation and stabilizes intermediate conformations on the folding pathway to the final β-hairpin., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: The role of exposure to air pollution in the development of allergic sensitization remains unclear., Objective: We sought to assess the development of sensitization until school age related to longitudinal exposure to air pollution from road traffic., Methods: More than 2500 children in the birth cohort BAMSE (Children, Allergy, Milieu, Stockholm, Epidemiological Survey) from Stockholm, Sweden, were followed with repeated questionnaires and blood sampling until 8 years of age. Outdoor concentrations of nitrogen oxides, as a marker of exhaust particles, and particles with an aerodynamic diameter of less than 10 μm (PM(10)), mainly representing road dust, were assigned to residential, day care, and school addresses by using dispersion models. Time-weighted average exposures were linked to levels of IgE against common inhalant and food allergens at 4 and 8 years of age., Results: Air pollution exposure during the first year of life was associated with an increased risk of pollen sensitization at 4 years of age (odds ratio, 1.83; 95% confidence interval, 1.02-3.28) for a 5th to 95th difference in exposure to nitrogen oxides. At 8 years, there was no general increase in the risk of sensitization; however, the risk of food sensitization was increased, particularly among children free of sensitization at 4 years of age (odds ratio, 2.30; 95% confidence interval, 1.10-4.82). Results were similar by using PM(10). No associations between air pollution exposure after the first year of life and sensitization were seen., Conclusion: Traffic-related air pollution exposure does not seem to increase the overall risk of sensitization to common inhalant and food allergens up to school age, but sensitization to certain allergens might be related to exposure during infancy., (Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

The neutrophil formyl peptide receptors (FPR1 and FPR2) are G-protein coupled receptors that can induce pro-inflammatory as well as anti-inflammatory activities when activated. Accordingly, these receptors may become therapeutic targets for the development of novel drugs to be used for reducing the inflammation induced injuries in asthma, rheumatoid arthritis, Alzheimer's disease, cardiovascular diseases and traumatic shock. We screened a library of more then 50K small compounds for an ability of the compounds to induce a transient rise in intracellular Ca(2+) in cells transfected to express FPR2 (earlier called FPRL1 or the lipoxin A(4) receptor). Ten agonist hits were selected for further analysis representing different chemical series and five new together with five earlier described molecules were further profiled. Compounds 1-10 gave rise to a calcium response in the FPR2 transfectants with EC(50) values ranging from 4×10(-9)M to 2×10(-7)M. All 10 compounds activated human neutrophils to release superoxide, and based on the potency of their activity, the three most potent activators of the neutrophil NADPH-oxidase were further characterized. These three agonists were largely resistant to inactivation by neutrophil produced reactive oxygen species and shown to trigger the same functional repertoire in neutrophils as earlier described peptide agonists. Accordingly they induced chemotaxis, granule mobilization and secretion of superoxide. Interestingly, the oxidase activity was largely inhibited by cyclosporine H, an FPR1 selective antagonist, but not by PBP10, an FPR2 selective inhibitor, suggesting that FPR1 is the preferred receptor in neutrophils for all three agonists., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: Air pollutants may induce airway inflammation and sensitization due to generation of reactive oxygen species. The genetic background to these mechanisms could be important effect modifiers., Objective: Our goal was to assess interactions between exposure to air pollution and single nucleotide polymorphisms (SNPs) in the beta2-adrenergic receptor (ADRB2), glutathione S-transferase P1 (GSTP1), and tumor necrosis factor (TNF) genes for development of childhood allergic disease., Methods: In a birth cohort originally of 4,089 children, we assessed air pollution from local traffic using nitrogen oxides (traffic NO(x)) as an indicator based on emission databases and dispersion modeling and estimated individual exposure through geocoding of home addresses. We measured peak expiratory flow rates and specific IgE for inhalant and food allergens at 4 years of age, and selected children with asthma symptoms up to 4 years of age (n = 542) and controls (n = 542) for genotyping., Results: Interaction effects on allergic sensitization were indicated between several GSTP1 SNPs and traffic NO(x) exposure during the first year of life (p(nominal) < 0.001-0.06). Children with Ile105Val/Val105Val genotypes were at increased risk of sensitization to any allergen when exposed to elevated levels of traffic NO(x) (for a difference between the 5th and 95th percentile of exposure: odds ratio = 2.4; 95% confidence interval, 1.0-5.3). In children with TNF-308 GA/AA genotypes, the GSTP1-NO(x) interaction effect was even more pronounced. We observed no conclusive interaction effects for ADRB2., Conclusion: The effect of air pollution from traffic on childhood allergy appears to be modified by GSTP1 and TNF variants, supporting a role of genes controlling the antioxidative system and inflammatory response in allergy.

Studies have presented conflicting associations between cat allergen exposure and sensitisation and atopic disease. We therefore investigated the association between the observed domestic cat allergen level and cat sensitisation in young children in four study populations from three European countries. We recruited children from a nested case-control study, which is composed of four ongoing birth cohorts conducted in three European countries. Children at 2-4 years of age in the four cohorts who were sensitised to cat allergens (n=106) were compared with 554 non-sensitised children (controls). House dust samples were collected when the children were 5 to 7 years old, and cat allergen levels were measured in ng/g dust and ng/m(2) surface area. In the German study population we found a positive association between domestic cat allergen in house dust and cat sensitisation (OR (CI)=3.01 (1.16, 7.99)) while in the Swedish study population, we found a negative association (OR (CI)=0.41 (0.16, 0.98)). No association was found in the Dutch study population (OR (CI)=0.83 (0.22, 2.93)). Looking into the family history of cat keeping, we found the lowest prevalence of cat sensitisation in children who were cat owners at the age of blood sampling (11%) and the highest prevalence was found in those who have had a cat but not anymore, at the age of blood sampling (41%). The mixed results may be explained by differences in age and avoidance patterns.

Background: Urban air pollution can trigger asthma symptoms in children, but there is conflicting evidence on effects of long-term exposure on lung function, onset of airway disease and allergic sensitization., Methods: The spatial distribution of nitrogen oxides from traffic (traffic-NOx) and inhalable particulate matter from traffic (traffic-PM10) in the study area was assessed with emission databases and dispersion modeling. Estimated levels were used to assign first-year exposure levels for children in a prospective birth cohort (n = 4089), by linking to geocoded home addresses. Parents in 4 Swedish municipalities provided questionnaire data on symptoms and exposures when the children were 2 months and 1, 2, and 4-year-old. At 4 years, 73% of the children underwent clinical examination including peak expiratory flow and specific IgE measurements., Results: Exposure to air pollution from traffic during the first year of life was associated with an excess risk of persistent wheezing (odds ratio [OR] for 44 microg/m3 [5th-95th percentile] difference in traffic-NOx = 1.60; 95% confidence interval [CI] = 1.09-2.36). Similar results were found for sensitization (measured as specific IgE) to inhalant allergens, especially pollen (OR for traffic-NOx = 1.67; 95% CI = 1.10-2.53), at the age of 4 years. Traffic-related air pollution exposure during the first year of life was also associated with lower lung function at 4 years of age. Results were similar using traffic-NOx and traffic-PM10 as indicators., Conclusions: Exposure to moderate levels of locally emitted air pollution from traffic early in life appears to influence the development of airway disease and sensitization in preschool children.

Diseases associated with protein fibril-formation, such as the prion diseases and Alzheimer's disease, are gaining increased attention due to their medical importance and complex origins. Using molecular dynamics (MD) simulations in an aqueous environment, we have studied the stability of the alpha-helix covering positions 15-25 of the amyloid beta-peptide (A beta) involved in Alzheimer's disease. The effects of residue replacements, including the effects of A beta disease related mutations, were also investigated. The MD simulations show a very early (2 ns) loss of alpha-helical structure for the Flemish (A beta(A21G)), Italian (A beta(E22K)), and Iowa (A beta(D23N)) forms associated with hereditary Alzheimer's disease. Similarly, an early (5 ns) loss of alpha-helical structure was observed for the Dutch (A beta(E22Q)) variant. MD here provides a possible explanation for the structural changes. Two variants of A beta, A beta(K16A,L17A,F20A) and A beta(V18A,F19A,F20A), that do not produce fibrils in vitro were also investigated. The A beta(V18A,F19A,F20A) initially loses its helical conformation but refolds into helix several times and spends most of the simulation time in helical conformation. However, the A beta(K16A,L17A,F20A) loses the alpha-helical structure after 5 ns and does not refold. For the wildtype A beta(1-40) and A beta(1-42), the helical conformation is lost after 5 ns or after 40 ns, respectively, while for the "familial" (A beta(A42T)) variant, the MD simulations suggest that a C-terminal beta-strand is stabilised, which could explain the fibrillation. The simulations for the Arctic (A beta(E22G)) variant indicate that the alpha-helix is kept for 2 ns, but reappears 2 ns later, whereafter it disappears after 10 ns. The MD results are in several cases compatible with known experimental data, but the correlation is not perfect, indicating that multimerisation tendency and other factors might also be important for fibril formation.

Few epidemiological studies report on reliability of exposure measurements even though this significantly influences the results of correlation and regression analysis often used in these studies. Poor reliability of exposure measurement reduces the ability to detect a true association between a certain component and health outcome variables. The aim of this study was to determine the ratio of the within-home and between-home components of variance of a number of biocontaminants measured in house dust in the framework of an international study conducted in the Netherlands, Germany and Sweden (the AIRALLERG study). To this end, duplicate dust samples were collected from children's beds and from living room floors in over 100 homes. Samples were taken at the same point in time. Variables considered were the dust mass collected in mg/m2 and the concentrations of the house dust mite allergens Der p 1 and Der f 1, cat allergen Fel d 1, endotoxin, (1 --> 3)-beta-D-glucan and extracellular polysaccharides, all per gram of dust and per square meter of sampling surface. An analysis of variance showed that the within-home variance was small compared to the between-home variance for most variables (mostly less than half) with the exception of glucan on mattresses, when expressed in mug/g. Investigation of variation over time is needed for a more complete assessment of the use of these variables in epidemiological analyses of exposure-response relationships.

Background: It has been suggested that noise exposure increases the risk of hypertension. Road traffic is the dominant source of community noise exposure., Objective: To study the association between exposure to residential road traffic noise and hypertension in an urban municipality., Methods: The study population comprised randomly selected subjects aged 19-80 years. A postal questionnaire provided information on individual characteristics, including diagnosis of hypertension. The response rate was 77%, resulting in a study population of 667 subjects. The outdoor equivalent traffic noise level (Leq 24 h) at the residence of each individual was determined using noise-dispersion models and manual noise assessments. The individual noise exposure was classified in units of 5 dB(A), from <45 dB(A) to >65 dB(A)., Results: The odds ratio (OR) for hypertension adjusted for age, smoking, occupational status and house type was 1.38 (95% confidence interval (CI) 1.06 to 1.80) per 5 dB(A) increase in noise exposure. The association seemed stronger among women (OR 1.71; 95% CI 1.17 to 2.50) and among those who had lived at the address for >10 years (OR 1.93; 95% CI 1.29 to 2.83). Analyses of categorical exposure variables suggested an exposure-response relationship. The strongest association between exposure to traffic noise and hypertension was found among those with the least expected misclassification of true individual exposure, as indicated by not having triple-glazed windows, living in an old house and having the bedroom window facing a street (OR 2.47; 95% CI 1.38 to 4.43)., Conclusion: The results of our study suggest an association between exposure to residential road traffic noise and hypertension.

Background: Mold growth is believed to be one causative factor underlying the association between dampness in buildings and increased respiratory morbidity. Measurements of beta(1-->3)-glucans and fungal extracellular polysaccharides (EPS) are used as markers of mold exposure in field studies. Little is known about their levels and determinants in homes., Objective: To study levels and determinants of beta(1-->3)-glucan and EPS levels in mattress and living room floor dust in three European countries., Methods: Mattress and living room floor dust was collected in the homes of 1065 German, Dutch, and Swedish (pre-)school children. All samples were analyzed for beta(1-->3)-glucans and EPS in one central laboratory. Determinants were assessed by questionnaire., Results: Amounts of dust, EPS and beta(1-->3)-glucan levels differed between countries. Amounts of dust, beta(1-->3)-glucan and EPS levels for mattresses were only weakly correlated with those for living room floors. Floor dust beta(1-->3)-glucan loads, EPS loads and EPS concentrations were strongly correlated with the amount of dust sampled, which is largely determined by the type of floor that was sampled (carpeted floors had 5-20 higher amounts of dust). None of the other determinants was consistently and statistically significantly associated with amounts of dust, beta(1-->3)-glucan and EPS concentrations on floors and mattresses., Conclusion: Mattress dust and floor dust are two different measures of exposure to the investigated mold components. Living room floor beta(1-->3)-glucan and EPS loads and EPS concentrations are largely determined by the type of floor sampled. Differences between countries can only partly be explained by the determinants studied.

Introduction: Cat allergen is a major cause of morbidity among sensitised asthma patients, but little is known about distribution of cat allergen exposure and its determinants in homes., Methods: We measured cat allergen and potential determinants of cat allergen levels in more than 1000 homes. House dust was collected from children's mattresses and living room floors in approximately 360 homes in The Netherlands, Sweden and Germany and analysed for Fel d 1 in one central laboratory. Exposure was expressed both in concentration (ng/g) and in loads (ng/m2)., Results: Levels on mattresses were similar in Sweden and Germany but higher on Dutch mattresses. Dutch floors had higher concentrations than Swedish floors, which had higher concentrations than German floors. The differences in load were less clear. Cat allergen on mattress and floor were moderately to highly correlated. The most important variable quantifying cat allergen variation was the presence of a cat. Floor cover type and last time that floor was vacuumed were important in all three countries. The ratio of cat allergen loads between mattresses from homes with and without cats was higher for Sweden and Germany than for The Netherlands. This is likely related to higher prevalence of cat ownership in The Netherlands which leads to more contamination of homes in which cats were never held. Dust samples from 27-35% of mattresses from homes without cats contained more than 1000 ng/g cat allergen., Conclusion: With the exception of cat ownership and floor cover, questionnaire data on housing characteristics did not accurately predict cat allergen in the home.

Granulysin and NK-lysin are homologous bactericidal proteins with a moderate residue identity (35%), both of which have antimycobacterial activity. Short loop peptides derived from the antimycobacterial domains of granulysin, NK-lysin, and a putative chicken NK-lysin were examined and shown to have comparable antimycobacterial but variable Escherichia coli activities. The known structure of the NK-lysin loop peptide was used to predict the structure of the equivalent peptides of granulysin and chicken NK-lysin by homology modeling. The last two adopted a secondary structure almost identical to that of NK-lysin. All three peptides form very similar three-dimensional (3-D) architectures in which the important basic residues assume the same positions in space. The basic residues in granulysin are arginine, while those in NK-lysin and chicken NK-lysin are a mixture of arginine and lysine. We altered the ratio of arginine to lysine in the granulysin fragment to examine the importance of basic residues for antimycobacterial activity. The alteration of the amino acids reduced the activity against E. coli to a larger extent than that against Mycobacterium smegmatis. In granulysin, the arginines in the loop structure are not crucial for antimycobacterial activity but are important for cytotoxicity. We suggest that the antibacterial domains of the related proteins granulysin, NK-lysin, and chicken NK-lysin have conserved their 3-D structure and their function against mycobacteria.

Herein a general concept for the design of targeted libraries for proteins with binding sites that are divided into subsites is laid out, including several practical aspects and their solutions. The design is based on a chemogenomic classification of the subsites followed by collection of bioactive molecular fragments and virtual library generation. The general process is outlined and applied to the assembly of a library of 500 molecules targeting the serotonin type 7 (5-HT7) receptor, a class A G-Protein Coupled Receptor (GPCR). Utilizing commercially available building blocks of similar size and composition, a reference library was created. Control sets of known ligands for the 5-HT7 receptor, other GPCRs, and nuclear receptors were collected from literature sources. Principal component analysis of molecular descriptors for the two libraries and the literature sets, displayed a focusing of the targeted library to the region in the chemical space defined by the literature actives, suggesting a denser coverage of the bioactive region than for the more diverse reference library. Additional computational validations, including PCA class predictions, 3D pharmacophore modeling, and docking calculations all indicated an enrichment factor of 5-HT7 ligand-like molecules in the range of 2-4 for the targeted library compared to the reference library.

Several proteins and peptides that can convert from alpha-helical to beta-sheet conformation and form amyloid fibrils, including the amyloid beta-peptide (Abeta) and the prion protein, contain a discordant alpha-helix that is composed of residues that strongly favor beta-strand formation. In their native states, 37 of 38 discordant helices are now found to interact with other protein segments or with lipid membranes, but Abeta apparently lacks such interactions. The helical propensity of the Abeta discordant region (K16LVFFAED23) is increased by introducing V18A/F19A/F20A replacements, and this is associated with reduced fibril formation. Addition of the tripeptide KAD or phospho-L-serine likewise increases the alpha-helical content of Abeta(12-28) and reduces aggregation and fibril formation of Abeta(1-40), Abeta(12-28), Abeta(12-24), and Abeta(14-23). In contrast, tripeptides with all-neutral, all-acidic or all-basic side chains, as well as phosphoethanolamine, phosphocholine, and phosphoglycerol have no significant effects on Abeta secondary structure or fibril formation. These data suggest that in free Abeta, the discordant alpha-helix lacks stabilizing interactions (likely as a consequence of proteolytic removal from a membrane-associated precursor protein) and that stabilization of this helix can reduce fibril formation.

17beta-hydroxysteroid dehydrogenases (17beta-HSDs) catalyse the conversion of 17beta-OH (-hydroxy)/17-oxo groups of steroids, and are essential in mammalian hormone physiology. At present, eleven 17beta-HSD isoforms have been defined in mammals, with different tissue-expression and substrate-conversion patterns. We analysed 17beta-HSD type 10 (17beta-HSD10) from humans and Drosophila, the latter known to be essential in development. In addition to the known hydroxyacyl-CoA dehydrogenase, and 3alpha-OH and 17beta-OH activities with sex steroids, we here demonstrate novel activities of 17beta-HSD10. Both species variants oxidize the 20beta-OH and 21-OH groups in C21 steroids, and act as 7beta-OH dehydrogenases of ursodeoxycholic or isoursodeoxycholic acid (also known as 7beta-hydroxylithocholic acid or 7beta-hydroxyisolithocholic acid respectively). Additionally, the human orthologue oxidizes the 7alpha-OH of chenodeoxycholic acid (5beta-cholanic acid, 3alpha,7alpha-diol) and cholic acid (5beta-cholanic acid). These novel substrate specificities are explained by homology models based on the orthologous rat crystal structure, showing a wide hydrophobic cleft, capable of accommodating steroids in different orientations. These properties suggest that the human enzyme is involved in glucocorticoid and gestagen catabolism, and participates in bile acid isomerization. Confocal microscopy and electron microscopy studies reveal that the human form is localized to mitochondria, whereas Drosophila 17beta-HSD10 shows a cytosolic localization pattern, possibly due to an N-terminal sequence difference that in human 17beta-HSD10 constitutes a mitochondrial targeting signal, extending into the Rossmann-fold motif.

Short-chain dehydrogenases/reductases (SDR) form a large, functionally heterogeneous protein family presently with about 3000 primary and about 30 3D structures deposited in databases. Despite low sequence identities between different forms (about 15-30%), the 3D structures display highly similar alpha/beta folding patterns with a central beta-sheet, typical of the Rossmann-fold. Based on distinct sequence motifs functional assignments and classifications are possible, making it possible to build a general nomenclature system. Recent mutagenetic and structural studies considerably extend the knowledge on the general reaction mechanism, thereby establishing a catalytic tetrad of Asn-Ser-Tyr-Lys residues, which presumably form the framework for a proton relay system including the 2'-OH of the nicotinamide ribose, similar to the mechanism found in horse liver ADH. Based on their cellular functions, several SDR enzymes appear as possible and promising pharmacological targets with application areas spanning hormone-dependent cancer forms or metabolic diseases such as obesity and diabetes, and infectious diseases.

Eukaryotic genomes code for at least eight medium-chain dehydrogenases/reductases (MDR) enzyme families of two types, with and without Zn(2+) at the active site. Four families have Zn(2+): 'Dimeric alcohol dehydrogenases (ADHs)' (including liver ADHs), 'Tetrameric ADHs' (including the yeast ADHs), 'Cinnamyl ADHs' and 'Polyol DHs'. In the human genome, there are minimally 23 MDR genes, but the list is still growing from further interpretations. Of these, seven genes on chromosome 4 (and three pseudogenes) represent the ADH classes in the gene order IV, Igamma, Ibeta, Ialpha, V, II and III. The lineages leading to human ADH establish five levels of divergence, with nodes at the MDR/short-chain dehydrogenases/reductases (SDR), dimer/tetramer, class III/non-III, further class, and intraclass levels of divergence. These multiplicities allow conclusions on pathways of function for ADHs and suggest this activity to have two roles in addition to its function in metabolism, one of a basic defence nature, the other of regulatory value in higher eukaryotes.

Completed eukaryotic genomes were screened for medium-chain dehydrogenases/reductases (MDR). In the human genome, 23 MDR forms were found, a number that probably will increase, because the genome is not yet fully interpreted. Partial sequences already indicate that at least three further members exist. Within the MDR superfamily, at least eight families were distinguished. Three families are formed by dimeric alcohol dehydrogenases (ADH; originally detected in animals/plants), cinnamyl alcohol dehydrogenases (originally detected in plants) and tetrameric alcohol dehydrogenases (originally detected in yeast). Three further families are centred around forms initially detected as mitochondrial respiratory function proteins, acetyl-CoA reductases of fatty acid synthases, and leukotriene B4 dehydrogenases. The two remaining families with polyol dehydrogenases (originally detected as sorbitol dehydrogenase) and quinone reductases (originally detected as zeta-crystallin) are also distinct but with variable sequences. The most abundant families in the human genome are the dimeric ADH forms and the quinone oxidoreductases. The eukaryotic patterns are different from those of Escherichia coli. The different families were further evaluated by molecular modelling of their active sites as to geometry, hydrophobicity and volume of substrate-binding pockets. Finally, sequence patterns were derived that are diagnostic for the different families and can be used in genome annotations.