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The efficacy of a sanitizer in biofilm removal may be influenced by a combination of factors such as sanitizer exposure time and concentration, bacterial species, surface topography, and shear stresses. We employed an inline biofilm reactor to investigate the interactions of these variables on biofilm removal with chlorine. The CDC bioreactor was used to grow E. coli O157:H7 and L. monocytogenes biofilms as a single species or with Ralstonia insidiosa as a dual-species biofilm on stainless steel, PTFE, and EPDM coupons at shear stresses 0.368 and 2.462 N/m2 for 48 hours. Coupons were retrieved from a CDC bioreactor and placed in an inline biofilm reactor and 100, 200, or 500 ppm of chlorine was supplied for 1- and 4 min. Bacterial populations in the biofilms were quantified pre- and posttreatment by plating on selective media. After chlorine treatment, reduction (Log CFU/cm2) in pathogen populations obtained from three replicates was analyzed for statistical significance. A 1-min chlorine treatment (500 ppm), on dual-species E. coli O157:H7 biofilms grown at high shear stress of 2.462 N/m2 resulted in significant E. coli O157:H7 reductions on SS 316L (2.79 log CFU/cm2) and PTFE (1.76 log CFU/cm2). Similar trend was also observed for biofilm removal after a 4-min chlorine treatment. Single species E. coli O157:H7 biofilms exhibited higher resistance to chlorine when biofilms were developed at high shear stress. The effect of chlorine in L. monocytogenes removal from dual-species biofilms was dependent primarily on the shear stress at which they were formed rather than the surface topography of materials. Besides surface topography, shear stresses at which biofilms were formed also influenced the effect of sanitizer. The removal of E. coli O157:H7 biofilms from EPDM material may require critical interventions due to difficulty in removing this pathogen. The inline biofilm reactor is a novel tool to evaluate the efficacy of a sanitizer in bacterial biofilm removal.

The smooth variable structure filter (SVSF) is highly robust to modeling uncertainty and unknown disturbances. Recent developments to the SVSF have allowed for the creation of an adaptive estimation scheme termed the SVSF-KF, which balances the optimality of the Kalman filter (KF) with the robustness of the SVSF. The approach utilizes the KF estimate during normal operation, and utilizes the robust SVSF gain to estimate the states during the presence of a fault. However, the gain adaptation involved in detecting a fault and switching between the KF and SVSF estimates suffers from several limitations, including unwanted chattering. In this work, we review the original SVSF-KF approach and present two novel SVSF-KF strategies based on the normalized innovation square metric and the interacting multiple model strategy to address these limitations. Experimental simulations involving a simple harmonic oscillator subject to a fault condition are conducted, which verify the effectiveness of our proposed approaches.

Spatial life course epidemiological approaches offer promise for prospectively examining the impacts of air pollution exposure on longer-term health outcomes, but existing research is limited. An essential aspect, often overlooked is the comprehensiveness of exposure data across the lifecourse. The primary objective was to meticulously reconstruct historical estimates of air pollution exposure to include prenatal exposure as well as annual exposure from birth to 10 years (1977-1987) for each cohort member. We linked these data from a birth cohort of 1,265 individuals, born in Aotearoa/New Zealand in mid-1977 and studied to age 40, to historical air pollution data to create estimates of exposure from birth to 10 years (1977-1987). Improvements in air quality over time were found. However, outcomes varied by demographic and socioeconomic factors. Future research should examine how inequitable air pollution exposure is related to health outcomes over the life course., Competing Interests: Declaration of competing interest All authors declare no conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Mental health conditions pose a significant public health challenge, and low area-level socioeconomic status (SES) is a potentially important upstream determinant. Childhood exposure might have influences on later-life mental health. This study, utilises data from the Christchurch Health and Development Study birth cohort, examining the impact of area-level SES trajectories in childhood (from birth to age 16) on mental health at age 16 and from age 18-40 years. Findings revealed some associations between distinct SES trajectories and mental health. The study underscores the importance of using a spatial lifecourse epidemiology framework to understand long-term environmental impacts on later-life health., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study investigated associations between change in the food environment and change in measured body mass index (BMI) and waist circumference (WC) in the Christchurch Health and Development Study (CHDS) birth cohort. Our findings suggest that cohort members who experienced the greatest proportional change towards better access to fast food outlets had the slightly larger increases in BMI and WC. Contrastingly, cohort members who experienced the greatest proportional change towards shorter distance and better access to supermarkets had slightly smaller increases in BMI and WC. Our findings may help explain the changes in BMI and WC at a population level., Competing Interests: Declaration of competing interest The authors declare they have nothing to disclose., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Symbiogenesis, literally 'becoming by living together', refers to the crucial role of symbiosis in major evolutionary innovations. The term usually is reserved for the major transition to eukaryotes and to photosynthesising eukaryotic algae and plants by endosymbiosis. However, in some eukaryote lineages endosymbionts have been lost secondarily, showing that symbiosis can trigger a major evolutionary innovation, even if symbionts were lost secondarily. This leads to the intriguing possibility that symbiosis has played a role in other major evolutionary innovations as well, even if not all extant representatives of such groups still have the symbiotic association. We evaluate this hypothesis for two innovations in termites (Termitoidae, also known informally as "Isoptera"): i) the role of flagellate gut protist symbionts in the transition to eusociality from cockroach-like ancestors, and ii) the role of non-gut associated symbionts in the transition to 'higher' termites, characterized by the absence of flagellate gut protists. In both cases we identify a crucial role for symbionts, even though in both cases, subsequently, symbionts were lost again in some lineages. We also briefly discuss additional possible examples of symbiogenesis. We conclude that symbiogenesis is more broadly applicable than just for the endosymbiotic origin of eukaryotes and photosynthetic eukaryotes, and may be a useful concept to acknowledge the important role of symbiosis for evolutionary innovation. However, we do not accept Lynn Margulis's view that symbiogenesis will lead to a paradigm shift from neoDarwinism, as the role of symbiosis in evolutionary change can be integrated with existing theory perfectly., (Copyright © 2017. Published by Elsevier Ltd.)

Calreticulin (CRT) and citrullinated (citCRT) are implicated in rheumatoid arthritis (RA) pathology. citCRT binds to RA shared epitopes (SE) on HLA-DR molecules with high affinity and triggers pro-inflammatory events in adjacent cells. The aim of the study was to detect the presence of citCRT prior to developing RA and evaluate if citCT is a target for autoantibodies in RA cohorts with and without lung disease. Antibodies were assessed by ELISA against native CRT, citCRT and general protein citrullination, in sera from 50 RA patients without lung disease, 122 bronchiectasis (BR) patients, 52 bronchiectasis patients with RA (BRRA), 87 asthma patients and 77 healthy controls (HC). Serum citCRT was detected by immunoblotting and mass spectrometry. Genomic DNA was genotyped for HLA-DRB1 alleles. Patients were assessed for DAS28, rheumatoid factor, and anti-cyclic citrullinated peptide antibodies. Extracellular citCRT was detected in BR patients sera prior to them developing RA. A citCRT SE binding peptide GEWKPR 261cit QIDNPDYK was identified. Anti-CRT antibodies were observed in 18% of BR patients with or without RA. Anti-citCRT antibodies were observed in ∼35% of BR or RA patients, increasing to 58% in BRRA patients. In the RA alone patients 7/20 (35%) who were negative for RF and anti-CCP were anti-CRT antibody positive and had higher DAS28 scores than triple negative RA alone patients. Three of the four BR patients who developed RA over 18 months were anti-citCRT+ve SE +ve . The detection of citCRT in BR and development of anti-citCRT in BR patients suggests citCRT antigens are early targets of antigenicity in these patients, especially in SE +ve patients prior to the onset of RA., (Copyright © 2017. Published by Elsevier Ltd.)

Peroxiredoxin 2 has immune regulatory functions, but its expression in human peripheral blood lymphocytes and levels in extracellular fluid in healthy subjects and rheumatoid arthritis patients are poorly described. In the present study, the median intracellular peroxiredoxin 2 protein content of lymphocytes from rheumatoid arthritis patients was more than two-fold higher compared with healthy subjects' lymphocytes. Intracellular peroxiredoxin 3 levels were similar in healthy and rheumatoid arthritis lymphocytes. Flow cytometry detected peroxiredoxin 2 on the surface of ca. 8% of T cells and ca. 56% of B cells (median % values) of all subjects analyzed. Exofacial thioredoxin-1 was also observed. In the total lymphocyte population from rheumatoid arthritis patients, few cells (median, 6%) displayed surface peroxiredoxin 2. In contrast, a significantly increased proportion of interleukin-17(+ve) lymphocytes were exofacially peroxiredoxin 2(+ve) (median, 39%). Prdx2 was also detected in human extracellular fluids. We suggest that crucial inflammatory cell subsets, i.e. interleukin-17(+ve) T cells, exhibit increased exofacial redox-regulating enzymes and that peroxiredoxin 2 may be involved in the persistence of pro-inflammatory cells in chronic inflammation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Calreticulin (CRT) is an endoplasmic reticulum (ER) chaperone responsible for glycoprotein folding and Ca(2+) homeostasis. CRT also has extracellular functions, e.g. tumor and apoptotic cell recognition and wound healing, but the mechanism of CRT extracellular release is unknown. Cytosolic localization of CRT is determined by signal peptide and subsequent retrotranslocation of CRT into the cytoplasm. Here, we show that under apoptotic stress conditions, the cytosolic concentration of CRT increases and associates with phosphatidylserine (PS) in a Ca(2)(+)-dependent manner. PS distribution is regulated by aminophospholipid translocase (APLT), which maintains PS on the cytosolic side of the cell membrane. APLT is sensitive to redox modifications of its SH groups by reactive nitrogen species. During apoptosis, both CRT expression and the concentration of nitric oxide (NO) increase. By using S-nitroso-l-cysteine-ethyl-ester, an intracellular NO donor and inhibitor of APLT, we showed that PS and CRT externalization occurred together in an S-nitrosothiol-dependent and caspase-independent manner. Furthermore, the CRT and PS are relocated as punctate clusters on the cell surface. Thus, CRT induced nitrosylation and its externalization with PS could explain how CRT acts as a bridging molecule during apoptotic cell clearance., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

The Ewing Sarcoma (EWS) protein is a ubiquitously expressed RNA processing factor that localises predominantly to the nucleus. However, the mechanism through which EWS enters the nucleus remains unclear, with differing reports identifying three separate import signals within the EWS protein. Here we have utilized a panel of truncated EWS proteins to clarify the reported nuclear localisation signals. We describe three C-terminal domains that are important for efficient EWS nuclear localization: (1) the third RGG-motif; (2) the last 10 amino acids (known as the PY-import motif); and (3) the zinc-finger motif. Although these three domains are involved in nuclear import, they are not independently capable of driving the efficient import of a GFP-moiety. However, collectively they form a complex tripartite signal that efficiently drives GFP-import into the nucleus. This study helps clarify the EWS import signal, and the identification of the involvement of both the RGG- and zinc-finger motifs has wide reaching implications.

The two lung surfactant collectins, surfactant protein (SP)-A and SP-D, are involved in host defence against infectious and allergenic agents via enhancement of killing and clearance by macrophages and neutrophils. Recent gene-knockout, protein engineering and physiological studies have emphasised the roles that SP-A and SP-D play in acute inflammatory responses.

The respiratory quotient (RQ) at 28 degrees C was determined by Warburg manometry in 23 species of termites from the Mbalmayo Forest Reserve (Cameroon) and three sub-tropical species cultured under laboratory conditions in the U.K. or freshly collected in Australia. The data are tabulated with other recently reported RQs (determined by manometry or GC) and with measured CH(4) emission rates to provide a survey of 29 species covering both lower and higher termites in all major trophic (functional) categories. In all species, except the wood-feeding Coptotermes acinaciformis and the soil-feeding Cubitermes fungifaber, the observed mean values (with manometry corrected for known fluxes of H(2) and CH(4)) were at or well above 1.00. Soil-feeding forms (except C. fungifaber) generally showed a high apparent RQ (not corrected for H(2)), with nine species (out of 13) above 1.20 and six species above 1.30. Well-replicated laboratory experiments with Reticulitermes lucifugus showed that there was a tendency for RQ to fall with time over a 4-h incubation, although remaining greater than 1.00.The observed RQs are consistent with carbohydrate being the principal substrate supporting respiration in all trophic and taxonomic categories, with little or no contribution from the degradation of lignin or other polyaromatic materials. However, in many species (especially soil-feeders), the observed RQ is greater than that expected from known fluxes of O(2), CO(2) and CH(4) on the assumption that carbohydrate is the respiratory substrate. This presupposes that there is a large hydrogen sink (additional to CH(4) production), possibly the emission of H(2) gas, and/or the existence of unresolved digestive mechanisms or electron routings. Uncertainties in the use of manometry with termites are discussed.

In spite of the great diversity of animal lectins, a common characteristic is their ability to bind sugars by means of discrete, modular carbohydrate recognition domains, CRDs. Three different groups of animal lectins-galectins, P-type and C-type lectins- have different types of CRDs which they arrange in a number of combinations, in three dimensions, in order to increase the affinity for oligosaccharides associated with glycoconjugates. The necessity of combining multiple CRDs in a native lectin molecule in order to increase the affinity for multiple ligands is of great importance physiologically, since many of the carbohydrate structures associated with proteins exist in a variety of different conformations. Recent work has clarified the structural basis for carbohydrate recognition by some of these lectins.

The partial characterization and expression of the C1q receptor (C1q-R) in relation to other complement receptors present on the surface of neutrophils has been examined, as well as the effects of free C1q on cell function. A polyclonal anti-C1q-R antibody recognizes a 68-kD neutrophil surface protein. C1q-R expression was not upregulated upon warming, priming, or exposure to FMLP, but decreased after exposure to phorbol myristate acetate (PMA), because of shedding of the receptor into the extracellular medium, as detected by enzyme-linked immunosorbent assay. CR3 and CR1 expression was upregulated from intracellular pools after cell stimulation by PMA. No evidence of intracellular pools of C1q-R was found, as assessed by immunoblotting of subcellular fractions. But C1q-R appeared to be expressed early in cell differentiation, was detected on undifferentiated HL-60 cells, and like CR3 expression, increased upon 5 days differentiation towards a neutrophil lineage. However, C1q-R expression decreased upon additional culture, whereas CR3 expression continued to increase. A large variation in the percentage of peripheral cells expressing C1q receptors in donors was observed, ranging from 13% to 100%, contrasting with CR3 receptors that exhibited less variability. Interactions between free monomeric C1q and neutrophils were also studied. Incubation of stimulated neutrophils with 10 to 100 micrograms/mL C1q resulted in a further increase in CR3 expression and adherence to albumin-coated surfaces. Staphylococci opsonized with low quantities of C1q (0.1 to 1 microgram/mL) mediated a moderate and sustained respiratory burst in neutrophils, whereas a burst of similar magnitude was generated only with free C1q at concentrations 10- to 100-fold higher. Stimulation was only partially inhibited if cells were first treated with anti-C1q-R antibody, suggesting other C1q binding proteins may be present on the cell surface. In summary, neutrophil C1q receptor is approximately 68-kD, exhibits varying expression on different subjects, and is not upregulated from intracellular stores on exposure to soluble stimuli. Stimulated, but not resting, neutrophils selectively respond to raised levels of free C1q, resulting in altered cell function and enhanced CR3 receptor expression. These studies thus suggest complex roles for C1q in neutrophil function.

Isolated blood neutrophils from normal healthy subjects were separated into fractions by sequential countercurrent distribution (CCD) in a charge-sensitive dextran/polyethylene glycol aqueous phase system. The neutrophils separated as a broad profile, and in a charged phase procedure the separation was based upon differences in cell surface electrokinetic properties, as confirmed by electrophoretic mobility measurements of fractions across the profile using analytical cytopherometry. The CCD cell fractions were generally pooled as three or four major subfractions for analysis of functional and metabolic differences. These included measurements of chemotaxis, phagocytosis, and respiratory burst. An inverse relationship was found between the electrophoretic mobility (EPM) of the subfraction pools and their functional competence, with the less electronegative cell fraction pools often as much as 2 to 3-fold more active than the more electronegative pools. This demonstration of electrokinetic and functional heterogeneity in 'resting' neutrophil subpopulations separated by CCD may reflect changes during their sojourn in the circulation that determine selective margination and recruitment of cells to inflammatory foci and sites of infection.

A simple, rapid and economical method for the isolation of polymorphonuclear leucocytes (PMNs) from whole blood is compared with dextran and dextran/Lymphoprep gradient techniques. The method eliminates the use of dextran and density gradient polymers such as Ficoll which have been shown to affect PMNs adversely. The technique is based on the lysis of red cells with isotonic ammonium chloride solution followed by differential centrifugation to separate the PMNs. This method gave a PMN yield of 73% (SD +/- 3.5) and a purity of 78% (SD +/- 2.5). Both morphology and functional activity were preserved, as assessed by bacterial phagocytosis and killing, chemotaxis, polarising response, superoxide production and adherence. In contrast, the dextran and dextran/Lymphoprep techniques gave yields of 50% and 15% with purities of 78% and 91% respectively. In a series of 14 PMN isolations, the differential centrifugation method gave an average yield of 63% with an average purity of 83%.