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Rationale: Accurate measurement of trace compounds in blood samples is important in clinical diagnosis and life science. Ambient ionization mass spectrometry, however, suffers from the matrix effect when dealing with complex samples such as blood. Therefore, it is important to reduce the matrix effects in blood samples. Methods: A low-cost and disposable Teflon tube was used as a platform to precipitate the protein in blood. The analytes are extracted into organic solvent, and the precipitated protein can be adsorbed by the chromatography paper inserted. Therefore, the Teflon tube after precipitation can be directly subjected to paper spray ionization mass spectrometry, achieving one-step analysis of blood. Results: High sensitivity and satisfactory stability were achieved for pharmaceuticals, acids, and endogenic metabolites in blood. The absolute signal intensities of characteristic product ions of the tested analytes were 8–20 times higher after protein precipitation than those obtained using paper spray. Detection limits and quantitative performance were evaluated for three drugs: carbamazepine, metformin, and tioconazole. In addition, the limits of detection and quantitation were improved 9–14- and 8–12-fold, respectively. Conclusions: Protein precipitation coupled to paper spray with a tube and then to mass spectrometry was successfully achieved and applied in the one-step analysis of trace compounds in blood samples. The experimental results showed that this method was sensitive, stable, convenient, and economic for the direct analysis of blood. [ABSTRACT FROM AUTHOR]

Four different paper types were evaluated in vitro for their suitability for the collection of gingival crevicular fluid and its subsequent quantification using both the Periotron® 6000 and measurement of the area of paper wetted. Whatman 3MM chromatography paper (Wh.3MM) was found to be the most suitable and strip dimensions of 2 × 8 mm were found to be the most absorbent whilst remaining compatible with the dimensions of the Periotron electrodes. The 2 × 8 mm Wh.3MM paper strips were used to derive a quadratic calibration curve, for a range of fluid volumes, which was shown to be a better fit than a straight line, Recovery of human serum proteins applied to these strips exceeded 90% even after compression of the strip between the electrodes of the Periotron during fluid volume measurement. [ABSTRACT FROM AUTHOR]

Workplace‐collected blood spots deposited on filter paper were analysed with multiplexed affinity‐based protein assays and found to be suitable for proteomics analysis. The protein extension assay (PEA) was used to characterize 92 proteins using 1.2 mm punches in repeated samples collected from 20 workers. Overall, 97.8% of the samples and 91.3% of the analysed proteins passed quality control. Both within and between spot correlations using six replicates from the same individual were above 0.99, suggesting that comparable levels are obtained from multiple punches from the same spot and from consecutive spots. Protein levels from dried blood and wet serum from the same individuals were compared and the majority of the analysed proteins were found to be significantly correlated. These results open up for simplified sample collection of blood in field conditions for proteomic analysis, but also highlight that not all proteins can be robustly measured from dried whole blood. [ABSTRACT FROM AUTHOR]

Proteins immobilized on insoluble carriers or immunoadsorbents are now widely used in many areas of biological research. They are especially efficient in studies of complex protein mixtures because immunoadsorbents are very useful for isolation of individual components for further investigation. Antibodies immobilized on paper retain their specific activity and can be applied as very sensitive measurement tool. [ABSTRACT FROM AUTHOR]

Major studies are still lacking on the impact of differing intensities of long-term donor plasmapheresis, not only on total serum protein, albumin and immunoglobulin G (IgG), but also on humoral and cellular immunity, red cell and iron metabolism, and biochemical cardiovascular risk markers. Three groups of donors, comprising 483 individuals undergoing differing intensities of long-term serial plasmapheresis, were entered into a cross-sectional study. A fourth control group consisted of 100 non-donors. In addition to measuring total protein, albumin and IgG levels, we determined parameters of humoral and cellular immunity, red cell and iron metabolism and recognized biochemical cardiovascular risk factors. The median annual net amount of plasma donated by the three donor groups was 37, 16 and 10 l, respectively ( P < 0·0001). Donors had significantly lower total serum protein, albumin and IgG levels than non-donors ( P < 0·0001), but the intensity of plasmapheresis had no influence on those parameters. Like non-donors, all plasma donors had normal humoral and cellular immunity. No increased rates of iron store depletion were observed in the three groups of plasma donors. Plasma donors were not at increased cardiovascular risk. Regular donor plasmapheresis of up to 45 l of plasma per year appears to be as safe as more moderate plasmapheresis programmes, with respect to the parameters analysed in this study. Individuals donating under these conditions did not develop impaired humoral and cellular immunity, iron store depletion, or increased cardiovascular risk with regard to established biochemical risk markers. Prospective studies are required to determine more exactly than in retrospective analyses the reasons why donors withdraw from plasmapheresis programmes. [ABSTRACT FROM AUTHOR]

Patients with systemic lupus erythematosus (SLE) have an increased risk of thrombosis. Platelet-induced extracellular phosphorylation of plasma proteins suggests that this is due to persistent activation of the platelets. We examined 30 SLE patients (15 with thrombotic disease), 18 non-SLE patients with deep vein thrombosis (DVT) and 50 healthy controls by analysing β-thromboglobulin, activated factor XI-antithrombin complexes and fibrinogen-bound phosphate. All parameters were elevated in SLE patients, particularly those with thrombosis, but normal in DVT cases and healthy controls. We conclude that thrombotic disease in SLE patients is associated with a persistent systemic platelet activation that may lower the threshold for induction of thrombosis. [ABSTRACT FROM AUTHOR]

The aim of this retrospective study was to assess the effect of activated recombinant factor VII (rFVIIa) on the natural history of massive transfusion episodes. During 2002, outcome parameters were assessed in 50 patients transfused with more than 10 units of packed red cells. The effect of the addition of rFVIIa in 10 patients, with intractable bleeding, was then observed. Overall mortality was 20% at 24 h and 34% at 7 days. Severe coagulopathy was confirmed as a serious negative prognostic factor and occurred in 42% of patients overall, but in 70% of rFVIIa-treated patients. Transient cessation or reduction of bleeding was noted in 60% of patients following rFVIIa infusion. However, 24-h and 7-day mortality rates were 40% and 70%, respectively, in this group. Last-ditch rFVIIa therapy in patients resistant to conventional treatment did not rescue these patients or significantly alter outcomes. [ABSTRACT FROM AUTHOR]

Rationale: To open up new ways for matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS)‐based patient screening, blood serum is the most preferred specimen because of its richness in patho‐physiological information and due to ease of collection. To overcome deleterious freeze/thaw cycles and to reduce high costs for shipping and storage, we sought to develop a procedure which enables MALDI‐MS protein profiling of blood serum proteins without the need for serum freezing. Methods: Blood sera from patients/donors were divided into portions which after pre‐incubation were fast frozen. Thawed aliquots were deposited on filter paper discs and air‐dried at room temperature. Intact serum proteins were eluted with acid‐labile detergent‐containing solutions and were desalted by employing a reversed‐phase bead system. Purified protein solutions were screened by MALDI‐MS using standardized instrument settings. Results: MALDI mass spectra from protein solutions which were eluted from filter paper discs and desalted showed on average 25 strong ion signals (mass range m/z 6000 to 10,000) from intact serum proteins (apolipoproteins, complement proteins, transthyretin and hemoglobin) and from proteolytic processing products. Semi‐quantitative analysis of three ion pairs: m/z 6433 and 6631, m/z 8205 and 8916, as well as m/z 9275 and 9422, indicated that the mass spectra from either pre‐incubated fast‐frozen serum or pre‐incubated dried serum spot eluted serum contained the same information on protein composition. Conclusions: A workflow that avoids the conventional cold‐chain and yet enables the investigation of intact serum proteins and/or serum proteolysis products by MALDI‐MS profiling was developed. The presented protocol tremendously broadens the clinical application of MALDI‐MS and simultaneously allows a reduction in the costs for storage and shipping of serum samples. This will pave the way for clinical screening of patients also in areas with limited access to health care systems, and/or specialized laboratories. [ABSTRACT FROM AUTHOR]

Background: Hospital transfusion services order blood products to satisfy orders and maintain inventory levels during unexpected periods of increased blood demand. Surplus inventory may outdate before being allocated to a recipient. Blood product outdating is the largest contributor to blood wastage. Study Design: A province‐wide redistribution program was designed and implemented to redistribute near‐outdate plasma protein and related blood products from low‐usage to high‐usage hospitals. Program operations and details are described in this paper. Two transport container configurations were designed and validated for transport of all blood products. A cost‐analysis was performed to determine the effectiveness of this redistribution program. Results: A total of 130 hospital transfusion services contributed at least one near‐outdate blood product for redistribution between January 2012 and March 2020. These services redistributed 15,499 products through 3412 shipments, preventing the outdating of $17,570,700 CAD worth of product. Program costs were $14,900 for shipping and $30,000 for staffing. Failed time limits or non‐compliance with packing configurations resulted in $388,200 worth of blood products (97 shipments containing 816 products) being discarded. Courier transport delays was the most common reason (42/97; 43%) for transport failure. Conclusion: Redistributing near‐outdate blood products between hospitals is a feasible solution to minimize outdating. Despite heterogeneity of Canadian blood product inventory, all products (each with unique storage and transport requirements) were successfully redistributed in one of two validated and simple containers. Total operation costs of this program were small in comparison to the $17.6 million in savings associated with preventing the discard of outdated products. [ABSTRACT FROM AUTHOR]

Deep learning systems are typically designed to perform for a wide range of test inputs. For example, deep learning systems in autonomous cars are supposed to deal with traffic situations for which they were not specifically trained. In general, the ability to cope with a broad spectrum of unseen test inputs is called generalization. Generalization is definitely important in applications where the possible test inputs are known but plentiful or simply unknown, but there are also cases where the possible inputs are few and unlabeled but known beforehand. For example, medicine is currently interested in targeting treatments to individual patients; the number of patients at any given time is usually small (typically one), their diagnoses/responses are still unknown, but their general characteristics (such as genome information, protein levels in the blood, and so forth) are known before the treatment. We propose to call deep learning in such applications targeted deep learning. In this paper, we introduce a framework for targeted deep learning, and we devise and test an approach for adapting standard pipelines to the requirements of targeted deep learning. The approach is very general yet easy to use: It can be implemented as a simple data‐preprocessing step. We demonstrate on a variety of real‐world data that our approach can indeed render standard deep learning faster and more accurate when the test inputs are known beforehand. [ABSTRACT FROM AUTHOR]

Introduction: Hereditary factor X deficiency is a rare bleeding disorder, with limited treatment options. This paper describes the approach to pre‐clinical development and characterization of a high‐purity plasma‐derived factor X concentrate, to achieve orphan drug marketing authorization for the treatment of hereditary factor X deficiency. Methods: A chromatographic process was developed, to purify factor X from human plasma for fractionation. The product was characterized using in vitro, in vivo and ex vivo tests for potency, purity, thrombogenicity, immunogenicity, toxicity and stability. Results: The production process complied with good pharmaceutical manufacturing practice. It achieved 6000‐fold purification and 100‐fold concentration of the factor X protein compared to human plasma. The factor X protein was 94%–96% pure. Other residual plasma proteins were well below levels in plasma, minimizing potential interference in hemostasis after therapeutic administration. Effective virus‐reduction during manufacture, and the absence of thrombogenicity, toxicity and immunogenic potential were confirmed, addressing the main safety concerns historically associated with plasma‐derived therapeutics. The freeze‐dried product remained stable between +2°C and +30°C for at least three years. After reconstitution with water for injections, the factor X activity was maintained for at least 48 h at +18°C to +22°C. Conclusion: Targeted pre‐clinical development of the first highly‐purified concentrate to treat hereditary factor X deficiency is described. Following international guidelines for nonclinical safety testing, particular strategies were adopted for unmodified products derived from human blood plasma. This approach may also be relevant to the development of other ultra‐orphan medicinal products. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to fabricate novel nanoparticles (NPs) from a single disulfide bond‐bridged block copolymer poly(hydroxyethyl methacrylate)‐S‐S‐polycaprolactone (PHEMA‐S‐S‐PCL). The novel biomaterial was synthesized by ring‐opening polymerization and reversible addition–fragmentation chain transfer polymerization. The cargo‐free NPs were fabricated with the solvent evaporation method, and studies on NPs' characterizations were carried out. The hydrogen nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy spectra confirmed the synthesis of PHEMA‐S‐S‐PCL copolymer. Thermo‐gravimetric analysis curves indicated that the obtained PHEMA‐S‐S‐PCL copolymer had good thermostability. Transmission electron microscopy and dynamic light scatter results suggested that the cargo‐free NPs were in round shapes with an average diameter of 103.6 ± 0.12 nm. The low critical micelle concentration of cargo‐free NPs (7.9 × 10−4 mg/ml) indicated that these NPs would keep their spherical shapes after being attenuated by abundant liquid (e.g., blood or body fluid). Furthermore, these NPs showed high stability at the presence of bovine serum albumin. Therefore, it could be speculated that these NPs would not be absorbed by proteins in blood, and they could be used as a candidate carrier for drug delivery. [ABSTRACT FROM AUTHOR]

The urgent global public health need presented by severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) has brought scientists from diverse backgrounds together in an unprecedented international effort to rapidly identify interventions. There is a pressing need to apply clinical pharmacology principles and this has already been recognized by several other groups. However, one area that warrants additional specific consideration relates to plasma and tissue protein binding that broadly influences pharmacokinetics and pharmacodynamics. The principles of free drug theory have been forged and applied across drug development but are not currently being routinely applied for SARS‐CoV‐2 antiviral drugs. Consideration of protein binding is of critical importance to candidate selection but requires correct interpretation, in a drug‐specific manner, to avoid either underinterpretation or overinterpretation of its consequences. This paper represents a consensus from international researchers seeking to apply historical knowledge, which has underpinned highly successful antiviral drug development for other viruses, such as HIV and hepatitis C virus for decades. [ABSTRACT FROM AUTHOR]

Background and Objective: Azurocidin is a neutrophil-derived protein in gingival crevicular fluid (GCF) which, according to relevant studies, might correlate with periodontal disease. The aim of the present study was to evaluate azurocidin as a potential biomarker for chronic periodontitis., Material and Methods: One hundred and one patients participated in the study, divided into two groups. Forty-eight were included in the periodontally healthy group (HP) and fifty-three in the chronic periodontitis group (CP). Clinical indices included probing depth (PD), recession (REC), clinical attachment level (CAL), bleeding on probing (BOP) and plaque (PL). Pooled GCF samples were collected with paper strips, freezed in liquid nitrogen (-196°C), stored at -80°C, and the levels of azurocidin were analyzed with ELISA. Values were transformed and expressed for comparisons in pg/30 s sample. Statistical comparisons were performed using non-parametric tests (Mann-Whitney) at the 0.05 level. Furthermore, the diagnostic accuracy of the procedure was assessed with receiver operator characteristic curves (ROC), areas under the curve (AUC), and the Youden's J Index calculated., Results: Demographic data were comparable between the two groups. Clinical parameters and the levels of azurocidin were statistically significantly higher in the CP group when compared to the HP group (Mann-Whitney test, P < .05). Quantitative data from ELISA demonstrated a high diagnostic accuracy of azurocidin, with AUC calculated higher than 0.9 at the 0.000 level., Conclusion: Azurocidin in GCF is a promising biomarker for periodontal disease. The results of the present study agree with previous studies in the literature showing an up-regulated trend in the levels of azurocidin in periodontitis patients., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

There is a laboratory and clinical need to know the impact of direct oral anticoagulants (DOACs) on diagnostic tests to avoid misinterpretation of results. Although the regulatory labelling documents provide some information about the influences of each DOAC on diagnostic tests, these are usually limited to some of the most common tests and no head to head comparison is available. In this paper, we report the impact of DOACs on several thrombophilia tests, including assessment of antithrombin, protein S and protein C activity assays, detection of activated protein C resistance and assays used for lupus anticoagulant. Results are compared and discussed with data obtained from literature. The final goal of this comprehensive review is to provide practical recommendations for laboratories to avoid misdiagnosis due to oral direct factor Xa (FXa) or IIa (FIIa) inhibitors. Overall, oral direct FXa (apixaban, betrixaban, edoxaban and rivaroxaban) and FIIa (dabigatran) antagonists may affect clot‐based thrombophilia diagnostic tests resulting in false‐positive or false‐negative results. An effect on FIIa‐based thrombophilia diagnostic tests is observed with dabigatran but not with anti‐FXa DOACs and conversely for FXa‐based thrombophilia diagnostic tests. No impact was observed with antigenic/chromogenic methods for the assessment of protein S and C activity. In conclusion, interpretation of thrombophilia diagnostic tests results should be done with caution in patients on DOACs. The use of a device/chemical compound able to remove or antagonize the effect of DOACs or the development of new diagnostic tests insensitive to DOACs should be considered to minimize the risk of false results. [ABSTRACT FROM AUTHOR]

Mutations in the X‐linked phosphatidylinositol glycan, class A gene (Pig‐a) lead to loss of glycosylphosphatidylinositol (GPI) anchors and GPI‐anchored proteins from the surface of erythrocytes and other mammalian cells. The Pig‐a gene mutation assay quantifies in vivo gene mutation by immunofluorescent labeling and flow cytometry to detect the loss of GPI‐anchored proteins on peripheral blood erythrocytes. As part of the regulatory acceptance of the assay, a public database has been created that provides detailed information on Pig‐a gene mutation assays conducted in rats and mice. A searchable version of the database is available through a website designed and hosted by the University of Maryland School of Pharmacy. Currently, the database contains only mouse and rat data, but it is anticipated that it will expand to include data from other species, including humans. A major purpose in developing the database was to aid in the preparation of a Retrospective Performance Analysis and Detailed Review Paper required for Organisation for Economic Co‐operation and Development Test Guideline acceptance. We anticipate, however, that it also will be useful for accessing and comparing Pig‐a data to data from other assays and for conducting quantitative assessments of Pig‐a gene mutation responses. Environ. Mol. Mutagen., 60:759–762, 2019. © 2019 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Protein electrophoresis and immunotyping can be a useful adjunct to the standard biochemical techniques for characterizing serum and urine proteins. This paper reviews currently available and commonly used methods for diagnostic protein electrophoresis, including both agarose gel and capillary zone electrophoretic techniques and total protein assessments. Immunofixation and immunosubtraction methods for identification of immunoglobulin location and class are also presented. Practical application of quality assurance and quality control strategies in compliance with American Society of Veterinary Clinical Pathology (ASVCP) best practices are discussed. Commonly encountered serum and urine electrophoretic diagnostic patterns, including electrophoretically normal, acute‐phase protein responses, polyclonal gammopathies, restricted polyclonal/oligoclonal gammopathies, paraproteinemias (monoclonal or biclonal gammopathies), and Bence‐Jones proteinurias are also reviewed using relevant case material. Cases in which immunofixation electrophoresis are particularly useful are highlighted, and methodologies to more accurately quantify serum monoclonal proteins (M‐proteins), monitoring tests commonly used in human medicine, are discussed. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) have emerged as a promising tool for clinical liquid biopsy. However, the identification of EVs derived from blood samples is hindered by the presence of abundant plasma proteins, which impairs the downstream biochemical analysis of EV‐associated proteins and nucleic acids. Here, we employed optimized asymmetric flow field‐flow fractionation (AF4) combined with density cushion ultracentrifugation (UC) to obtain high‐purity and intact EVs with very low lipoprotein contamination from human plasma and serum. Further proteomic analysis revealed more than 1000 EV‐associated proteins, a large proportion of which has not been previously reported. Specifically, we found that cell‐line‐derived EV markers are incompatible with the identification of plasma‐EVs and proposed that the proteins MYCT1, TSPAN14, MPIG6B and MYADM, as well as the traditional EV markers CD63 and CD147, are plasma‐EV markers. Benefiting from the high‐purity of EVs, we conducted comprehensive miRNA profiling of plasma EVs and nanosized particles (NPs), as well as compared plasma‐ and serum‐derived EVs, which provides a valuable resource for the EV research community. Overall, our findings provide a comprehensive assessment of human blood EVs as a basis for clinical biopsy applications. [ABSTRACT FROM AUTHOR]

Nanostructured surfaces are effective at physically killing bacterial cells, highlighting their prospective application as biomaterials. The benefits of application of mechano‐bactericidal nanostructures as an alternative to chemical functionalisation are well documented, however, the effects of protein adsorption are not well understood. In this work, theoretical and experimental analyses are conducted by studying the adsorption of human serum proteins (HSP) to nanosheet titanium (Ti) and its subsequent effect on the mechano‐bactericidal efficacy toward Staphylococcus aureus and Pseudomonas aeruginosa cells. The nanosheet pattern exhibits enhanced antibiofouling behaviour mantaining high bactericidal efficiency toward both Gram‐negative and Gram‐positive cells in the presence of adsorbed HSP. To ascertain the immunomodulatory response, S. aureus cells are introduced to protein‐conditioned Ti nanosheet surfaces prior to introducing RAW 264.7 macrophages. On the pre‐infected nanostructured surfaces, macrophages exhibit wound healing behaviour with superior activation of M2‐like macrophage polarization and secretion of anti‐inflammatory cytokines. By contrast, macrophages attached to infected smooth surfaces activated the M1‐like polarized phenotype via the high expression of pro‐inflammatory cytokines, indicating persistent inflammation. The outcomes of this work demonstrate the suitability of Ti nanosheets as a potential biomaterial surface whereby the mechano‐bactericidal activity is not compromised by HSP adsorption and, furthermore, positively influenced an anti‐inflammatory immune response. [ABSTRACT FROM AUTHOR]

Superficial, systemic microcirculations, distinct from the pulmonary circulation, supply the mucosae of human nasal and conducting airways. Non‐injurious, inflammatory challenges of the airway mucosa cause extravasation without overt mucosal oedema. Instead, likely reflecting minimal increases in basolateral hydrostatic pressure, circulating proteins/peptides of all sizes are transmitted paracellularly across the juxtaposed epithelial barrier. Thus, small volumes of extravasated, unfiltered bulk plasma appear on the mucosal surface at nasal and bronchial sites of challenge. Importantly, the plasma‐exuding mucosa maintains barrier integrity against penetrability of inhaled molecules. Thus, one‐way epithelial penetrability, strict localization, and well‐controlled magnitude and duration are basic characteristics of the plasma exudation response in human intact airways. In vivo experiments in human‐like airways demonstrate that local plasma exudation is also induced by non‐sanguineous removal of epithelium over an intact basement membrane. This humoral response results in a protective, repair‐promoting barrier kept together by a fibrin‐fibronectin net. Plasma exudation stops once the provisional barrier is substituted by a new cellular cover consisting of speedily migrating repair cells, which may emanate from all types of epithelial cells bordering the denuded patch. Exuded plasma on the surface of human airways reflects physiological microvascular‐epithelial cooperation in first line mucosal defense at sites of intact and regenerating epithelium. [ABSTRACT FROM AUTHOR]

Background: To date, most existing models for predicting neuromyelitis optica spectrum disorder (NMOSD) are based primarily on clinical characteristics. Blood‐based NMOSD severity and prognostic predictive immune‐ and inflammation‐related biomarkers are needed. We aimed to investigate the associations between plasma inflammatory biomarkers and relapse and attack severity in NMOSD. Methods: This two‐step, single‐center prospective cohort study included discovery and validation cohorts. We quantified 92 plasma inflammatory proteins by using Olink's proximity extension assay and identified differentially expressed proteins in the relapse group (relapse within 1 year of follow‐up) and severe attack group. To define a new molecular prognostic model, we calculated the risk score of each patient based on the key protein signatures and validated the results in the validation cohort. Results: The relapse prediction model, including FGF‐23, DNER, GDNF, and SLAMF1, predicted the 1‐year relapse risk. The severe attack prediction model, including PD‐L1 and MCP‐2, predicted the severe clinical attack risk. Both the relapse and severe attack prediction models demonstrated good discriminative ability and high accuracy in the validation cohort. Conclusions: Our discovered biomarker signature and prediction models may complement current clinical risk stratification approaches. These inflammatory biomarkers could contribute to the discovery of therapeutic interventions and prevent NMOSD progression. [ABSTRACT FROM AUTHOR]

Studies of the potential role of the complement system in the pathogenesis of periodontal disease have involved measurements of complement cleavage in gingival fluid obtained from lesions of periodontitis. Due to the limited amounts of gingival fluid available from periodontal lesions. these studies have been confined to assessment of single complement components in lesions with significant inflammation. This paper presents a description and an evaluation of reliability of an improved method of sampling and complement assessment by crossed- immunoelectrophoresis which permits measurement of C3, C4, B, and their conversion products in single gingival fluid samples as small as 0.2 μl. Gingival fluid collected on filter paper strips and serum applied to strips as controls were subjected to crossed-immunoelectrophoresis using a multiple second-dimension gel composed of a 2 cm wide slab of agarose with anti-human B and anti-human Ci followed by another 2 cm slab containing anti-human C4 and anti-human transferrin (reference marker). Following drying and staining of the gels, the resultant precipitates were measured and the relative amount of each component and the percentage conversion of C3 determined. Using both fresh and activated serum, this technique was found to have a variability within 10%. Stability of complement measurements in gingival fluid was determined by duplicate sampling of 26 lesions of periodontitis prior to periodontal therapy. No significant differences were found in any of the components measured suggesting that the method produced reliable results from clinical samples. These findings establish this method as a sensitive and reliable means of assessment of complement cleavage in single samples of gingival fluid. This technique should be useful for longitudinal measurements of changes in complement during induction or resolution of periodontal disease. [ABSTRACT FROM AUTHOR]

The contribution of electrospun nanofibrous membranes (e.NFMs) in the biosensing platforms opens up a new prospect for the invention of faster and more sensitive analytical devices. In this paper, we utilized e.NFM of polyethersulfone (PES) as a solid substrate for the protein immobilization through two different approaches: physical and covalent. Scanning electron microscopy (SEM) and Fourier‐transform‐infrared (FTIR) tests were performed to study the effect of plasma treatment on protein immobilization efficacy. Moreover, taking advantage of ELISA technique, the influence of different parameters, namely, nanofibers diameter, membrane thickness, plasma treatment time, an incubation time of ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide/N‐hydroxysuccinimide (EDC/NHS), and their ratio on antibody immobilization efficacy through two mentioned approaches, was also assessed. [ABSTRACT FROM AUTHOR]

In transfusional iron overload, extra-hepatic iron distribution differs, depending on the underlying condition. Relative mechanisms of plasma non-transferrin bound iron ( NTBI) generation may account for these differences. Markers of iron metabolism (plasma NTBI, labile iron, hepcidin, transferrin, monocyte SLC40A1 [ferroportin]), erythropoiesis (growth differentiation factor 15, soluble transferrin receptor) and tissue hypoxia (erythropoietin) were compared in patients with Thalassaemia Major ( TM), Sickle Cell Disease and Diamond-Blackfan Anaemia ( DBA), with matched transfusion histories. The most striking differences between these conditions were relationships of NTBI to erythropoietic markers, leading us to propose three mechanisms of NTBI generation: iron overload (all), ineffective erythropoiesis (predominantly TM) and low transferrin-iron utilization ( DBA). [ABSTRACT FROM AUTHOR]

One of the key pharmacokinetic properties of most small molecule drugs is their ability to bind to serum proteins. Unbound or free drug is responsible for pharmacological activity while the balance between free and bound drug can impact drug distribution, elimination, and other safety parameters. In the hepatic impairment (HI) and renal impairment (RI) clinical studies, unbound drug concentration is often assessed; however, the relevance and impact of the protein binding (PB) results is largely limited. We analyzed published clinical safety and pharmacokinetic studies in subjects with HI or RI with PB assessment up to October 2022 and summarized the contribution of PB results on their label dose recommendations. Among drugs with HI publication, 32% (17/53) associated product labels include PB results in HI section. Of these, the majority (9/17, 53%) recommend dose adjustments consistent with observed PB change. Among drugs with RI publication, 27% (12/44) of associated product labels include PB results in RI section with the majority (7/12, 58%) recommending no dose adjustment, consistent with the reported absence of PB change. PB results were found to be consistent with a tailored dose recommendation in 53% and 58% of the approved labels for HI and RI section, respectively. We further discussed the interpretation challenges of PB results, explored treatment decision factors including total drug concentration, exposure–response relationships, and safety considerations in these case examples. Collectively, comprehending the alterations in free drug levels in HI and RI informs treatment decision through a risk‐based approach. [ABSTRACT FROM AUTHOR]

Introduction: Intervertebral disc degeneration and Modic change are the main spinal structural changes associated with chronic low back pain (LBP). Both conditions are thought to manifest local inflammation and if inflammatory proteins translocate to the blood circulation could be detected systemically. The work here assesses whether the presence of disc degeneration is associated with detectable blood level changes of five inflammatory markers and whether chronic LBP is associated with these changes. Materials and Methods: Two hundred and forty TwinsUK cohort participants with both MRI disc degeneration grade and Modic change extent, and IL‐6, IL‐8, IL‐8 TNF, and CX3CL1 protein blood concentration measurements were included in this work. Linear mixed effects models were used to test the association of blood cytokine concentration with disc degeneration score and Modic change volumetric score. Association of chronic LBP status from questionnaires with disc degeneration, Modic change, and cytokine blood concentration was also tested. Results: No statistically significant association between disc degeneration or Modic change with cytokine blood concentration was found. Instead, regression analysis pointed strong association between cytokine blood concentration with body mass index for IL‐6 and with age for IL‐6 and TNF. Mild association was found between IL‐8 blood concentration and body mass index. Additionally, LBP status was associated with Modic change volumetric score but not associated with any cytokine concentration. Conclusions: We found no evidence that Modic change and disc degeneration are able to produce changes in tested blood cytokine concentration. However, age and body mass index have strong influence on cytokine concentration and both are associated with the conditions studied which may confound associations found in the literature. It is then unlikely that cytokines produced in the disc or vertebral bone marrow induce chronic LBP. [ABSTRACT FROM AUTHOR]

Background: Seroma formation is the commonest early sequel to breast cancer surgery especially when axillary dissection is undertaken. It is associated with significant morbidity and financial burden. The main pathophysiology of seroma is still poorly understood and remains controversial. The optimal ways to reduce the incidence of seroma formation are unknown. The aim of this paper is to review the concepts of pathophysiology of seroma formation following mastectomy and breast-conserving surgery for cancer. The various techniques in practice to reduce its incidence and treatment are outlined. Method: MEDLINE search of published work on the subject with respect to its pathophysiology, prevention and treatment was carried out. Manual retrieval of relevant articles in the reference lists of the original papers from the MEDLINE was then carried out. Result: The pathophysiology and mechanism of seroma formation in breast cancer surgery remains controversial and not fully understood. Methods of prevention and treatment of seroma remain varied and inconclusive. Conclusion: Evidence suggests an increase in the incidence of seroma because of thermal trauma from electrocautery dissection, but this is indispensable for surgical haemostasis. Obliteration of dead space by various flap apposition techniques has been shown to be advantageous in reducing incidence and volume of seroma. Low-pressure suction drainage reduces seroma volume and duration of drainage leading to earlier drain removal. Preventive measures have to be tailored according to individual patient and operative factors. [ABSTRACT FROM AUTHOR]

In a previous paper [Lindley et al. (1993), Acta Cryst. D49, 292-304], the X-ray structure analysis of the 18 kDa fragment of duck ovotransferrin, corresponding to the Nil domain of the intact protein, was reported at a resolution of 2.3 Å. in this structure, the FeIII cation binds to two tyrosine residues and the synergistic carbonate anion in an identical manner to that found in the intact protein. However, the aspartate and histidine residues, normally involved in iron binding in transferrins, are absent in the fragment and it was not possible to unequivocally define what had replaced them. The electron density was tentatively assigned to be a mixture of peptides, presumably resulting from the proteolytic preparation of the fragment, binding to the iron through their amino and carboxylate termini. A more recent X-ray analysis of the fragment, from a different preparation, has resulted in a structure at 1.95 Å, in which glycine appears to be the predominant residue bound to the cation. in an alternative attempt to clarify the binding of iron to the 18 kDa fragment, the metal was removed by dialysis and replaced in the form of ferric nitrilotriacetate. Crystallization of this complex has resulted in an X-ray structure at 1.90 Å in which the FeII is bound to the synergistic carbonate anion and only one tyrosine residue in a manner almost identical to the intact protein. The carboxylate groups and the tertiary amino group of the nitrilotriacetate occupy the remaining coordination sites. The second tyrosine residue, Tyr95, is not bound directly to the iron. The implication of these structures with respect to the mechanism of iron binding by the transferrins is addressed. [ABSTRACT FROM AUTHOR]

Experiments demonstrating the feasibility of Kr-edge MAD on frozen crystals as a routine method for structure determination are reported. Approximately 50% of protein crystals can be successfully derivatized by pressurization with the noble gases xenon or krypton. While Xe has produced many useful derivatives for MIR phasing over the last several years, the Xe edges (K edge = 34.6 keV, L1 = 5.5 keV) are not easily accessible for MAD studies. As the Kr K edge (14.3 keV) is accessible on most MAD beamlines, Kr derivatization provides the additional opportunity to conduct a MAD experiment and obtain phases using only a single crystal. This paper describes the phasing of two proteins using Kr MAD: the 17 kDa Fe protein myoglobin (Mb) from sperm whale (Physeter catodon) and an 18 kDa protein (SP18) from green abalone (Haliotis fulgens). Three-wavelength data were collected at SSRL beamline 9-2 from crystals of Mb and SP18 incubated in 2.76 MPa of Kr gas for 2 min, depressurized and then flash-frozen in a stream of nitrogen gas at 100 K. MAD phases were calculated using the program SHARP and the resulting density improved with wARP. The final maps for both Mb and SP18 were of excellent quality. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The aim of this paper is to test whether α‐defensins and bacterial/permeability‐increasing protein were related to obesity and cardiovascular risk factors in prepubertal children. Methods: Plasma α‐defensins and bacterial/permeability‐increasing protein, body mass index (BMI), waist circumference, systolic blood pressure (SBP), carotid intima media thickness (cIMT), HOMA‐IR and HMW‐adiponectin were assessed. Results: In a cross‐sectional study (N = 250), higher α‐defensins concentrations were positively associated with BMI, waist, SBP, cIMT, HOMA‐IR and negative correlated with HMW‐adiponectin (all between r = 0.191 and r = 0.377, p ≤ 0.01 and p ≤ 0.0001). Conversely, plasma bacterial/permeability‐increasing protein concentrations presented inversed associated with the same parameters (all between r = −0.124 and r = −0.329; p ≤ 0.05 and p ≤ 0.0001). In a longitudinal study (N = 91), α‐defensins at age 7 were associated with BMI (β = 0.189, p = 0.002; model R2 = 0.847) and waist (β = 0.241, pthinsp;= 0.001; model R2 = 0.754) at age 10. Conclusions: α‐Defensins and bacterial/permeability‐increasing protein may be the markers of childhood obesity. Increased concentrations of α‐defensins may predict BMI and abdominal fat deposition in children. [ABSTRACT FROM AUTHOR]

Blood is generated in very large volumes as a by-product in slaughterhouses all around the world. On the one hand, blood generation presents a serious environmental issue because of its high pollutant capacity; however, on the other hand, blood has the potential to be collected and processed to generate high-added-value food ingredients based on its exceptional nutritive value and its excellent functional properties. In this paper, we review the current state of the art for blood processing, from collection to final recovery of protein isolates, the functional properties of blood, impact of processing on functional properties, and potential applications as food ingredients. Furthermore, future challenges are outlined for this underutilized and abundant product from the meat industry. [ABSTRACT FROM AUTHOR]

Haemophilia patients with inhibitors are treated for acute bleeding with prothrombin complex concentrates (PCCs) or activated prothrombin complex concentrates (aPCCs). Despite this therapy, patients with high-level inhibitors are at increased risk of developing devastating joint disease. This paper examines available information that supports the study of PCCs and/or aPCCs as prophylactic therapy for haemophilia patients with inhibitors. This strategy would require that PCCs or aPCCs be administered repetitively in a dose that is sufficient to prevent haemarthrosis without causing thrombogenic events, or causing anamnestic response in inhibitor titre. PCC doses ranging from 30 to 50 U kg-1 every other day for up to 8 months have resulted in subjective improvement both in bleeding associated with target joints and in the management of chronic joint inflammation. aPCC doses as low as 50–100 U kg-1 every other day have been useful in postsurgical prophylaxis. The risk of developing a myocardial infarction or clinically relevant disseminated intravascular coagulation is linked to total dosages of either PCCs or aPCCs greater than 200 U kg-1 day-1. It is uncertain what anamnestic response would result from prophylaxis, but with typical therapy the aPCCs cause such a response in only a small percentage of patients. Based on these findings, a clinical trial of these products used in doses of 50–100 U kg-1 every other day would appear to be warranted in patients who have permanent inhibitors and frequent joint bleeding. [ABSTRACT FROM AUTHOR]

Summary: The plant hormone auxin and its directional intercellular transport play a major role in diverse aspects of plant growth and development. The establishment of auxin gradients requires the asymmetric distribution of members of the auxin efflux carrier PIN‐FORMED (PIN) protein family to the plasma membrane. An endocytic pathway regulates the recycling of PIN proteins between the plasma membrane and endosomes, providing a mechanism for dynamic localisation.N‐Ethylmaleimide‐sensitive factor adaptor protein receptors (SNAP receptors, SNAREs) mediate fusion between vesicles and target membranes and are classed as Q‐ or R‐SNAREs based on their sequence. We analysed gain‐ and loss‐of‐function mutants, dominant‐negative transgenics and localisation of the Arabidopsis R‐SNARE VAMP714 protein to understand its function.We demonstrate that VAMP714 is essential for the insertion of PINs into the plasma membrane, for polar auxin transport, root gravitropism and morphogenesis. VAMP714 gene expression is upregulated by auxin, and the VAMP714 protein co‐localises with endoplasmic reticulum and Golgi vesicles and with PIN proteins at the plasma membrane.It is proposed that VAMP714 mediates the delivery of PIN‐carrying vesicles to the plasma membrane, and that this forms part of a positive regulatory loop in which auxin activates a VAMP714‐dependent PIN/auxin transport system to control development. [ABSTRACT FROM AUTHOR]

This paper describes a procedure for analysing multiple antibody reactivities that explores a commercially available immunoblot system, and is based on a double staining of nitrocellulose membranes, revealing both antibody reactivities and the migration position of the blotted proteins in the membrane. Quantification of both stainings by densitometry allowed the accurate superposition of the immunoreactivity and total protein profiles of each lane. Moreover, the protein stainings of the different lanes could be adjusted with a simple-scale transformation algorithm, correcting for possible distortions during electrophoretic migration, and allowing for the precise comparison of the immunoreactivity profiles in different lanes. The procedure is discriminatory enough to identify unique reactivity patterns in random pools of 104 activated B cells, and to define strain-specific natural antibody repertoires. The utility of this immunoblot method as an assay for simultaneously scoring multiple reactivities to hundreds of antigens in complex mixtures of antibodies, and thus defining antibody repertoires in a global manner, is discussed. [ABSTRACT FROM AUTHOR]

The primary structure of the 2265 residues of bovine plasma fibronectin has been completed. The new sequences reported in this paper are residues 600-868 (269 residues), 1138-1217 (80 residues), 1518 -1599 (82 residues) and 1868-2061 (194 residues). These sequences constitute six type II homology units and two non-monologous connecting strands. Thus, there are fifteen type III homology units in plasma fibronectin. Evidence for two of the three splice variant found in rat liver cels [Schwarzbauer et al. (1983) Cell 35, 421-431] was obtained. No indications of the 'extra' type III domain present in some human fibroblast fibronectins [Kornblihtt et al. (1984) EMBO J. 3, 221-226] was found. Three carbohydrate groups (two glucosamine-based and one galactosamine-based) were identified, giving a total of eight carbohydrate groups in the lowest splice variant of bovine plasma fibronectin. A second free sulfhydryl group (cysteine) was identified. This cysteine, like the first, is in a type III homology unit. HPLC patterns of peptides obtained from the C-terminal 6-kDa fragment suggested that the interchain bridge pattern of fibronectin is antiparallel. The bovine plasma fibronectin sequence is highly homologous to the human cellular fibronectin sequence deduced from the cDNA sequence [Kornblihtt et al. (1985) EMBO J. 4, 1755-1759]. [ABSTRACT FROM AUTHOR]

The expression of human transferrin and lactoferrin binding activity in Haemophilus influenzae, detected by a binding assay using human transferrin or lactoferrin conjugated to peroxidase, was regulated by the level of available iron in the medium. Transferrin binding activity was present in all H. influenzae isolates tested but not detected in other Haemophilus species or in species of Pasteurella or Actinobacillus. Lactoferrin binding activity was only detected in 1⁄15 H. influenzae isolates tested. The transferrin and lactoferrin receptors were shown to be specific for the respective human proteins by means of a competition binding assay. Competition binding assays also showed that iron-loaded transferrin was more effective at blocking the transferrin receptor than apotransferrin, but no differences in receptor blocking were observed between iron-loaded lactoferrin and apolactoferrin. [ABSTRACT FROM AUTHOR]

Protein glycosylation responds sensitively to disease states. It is implicated in every hallmark of cancer and has recently started to be considered as a hallmark itself. Changes in N‐glycosylation microheterogeneity are more dramatic than those of protein expression due to the non‐template nature of protein glycosylation. This enables their potential use in serum‐based diagnostics. Here, we perform glycopeptidomics on serum from patients with oropharyngeal squamous cell carcinoma (OPSCC), compared to controls and comparing between cancers based on etiology (human papilloma virus‐ positive or negative). Using MS2, we then targeted glycoforms, significantly different between the groups, to identify their glycopeptide compositions. Simultaneously we investigate the same serum proteins, comparing whether N‐glycosylation changes reflect protein‐level changes. Significant glycoforms were identified from proteins such as alpha‐1‐antitrypsin (SERPINA1), haptoglobin, and different immunoglobulins. SERPINA1 had glycovariance at 2 N‐glycosylation sites, that were up to 35 times more abundant in even early‐stage OPSCCs, despite minimal differences between SERPINA1 protein levels between groups. Some identified glycoforms' fold changes (FCs) were in line with serum protein level FCs, others were less abundant in early‐stage cancers but with great variance in higher‐stage cancers, such as on immunoglobulin heavy constant gamma 2, despite no change in protein levels. Such findings indicate that glycovariant analysis might be more beneficial than proteomic analysis, which is yet to be fruitful in the search for biomarkers. Highly sensitive glycopeptide changes could potentially be used in the future for cancer screening. Additionally, characterizing the glycopeptide changes in OPSCC is valuable in the search for potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Glycidol fatty acid esters that are present in foods are degraded in vivo to the animal carcinogen glycidol, which binds to the N‐terminal valine of hemoglobin (Hb) to form N‐(2,3‐dihydroxypropyl)valine (diHOPrVal) adducts. The existence of other chemicals that are converted to glycidol is unknown. To determine the effect of different exposure conditions on the formation of diHOPrVal adducts, several glycidol‐related chemicals (3‐monochloropropane‐1,2‐diol; 3‐MCPD, epichlorohydrin, glyceraldehyde, acrylic acid, and 1,2‐propanediol) were evaluated using in vitro and in vivo (single/repeated dose) methods. In vitro, the reaction of 3‐MCPD or epichlorohydrin with human Hb produced 17% and 0.7% of diHOPrVal, as compared to equimolar glycidol, respectively. Following a single administration of glycidol‐related compounds to ICR mice, diHOPrVal formation was observed only in the epichlorohydrin‐treated group after day 5 of exposure. After 14 days of repeated dosing, the amounts of diHOPrVal produced by epichlorohydrin and 3‐MCPD in vivo were <1% of diHOPrVal produced by an equal molar concentration of glycidol. Furthermore, glyceraldehyde group produced 0.2% of diHOPrVal at the same molar concentration of glycidol equivalents, in which diHOPrVal formation could not be confirmed by the in vitro assay. The results indicate the usefulness of diHOPrVal as an exposure marker for glycidol; however, the contribution of its formation in vivo by exposure to various chemicals will be necessary to validate and interpret the results. [ABSTRACT FROM AUTHOR]

Introduction: Severe COVID‐19 management is still challenging. Having a laboratory factor to predict the severity of a patient's condition can be very useful in how to approach each patient. There have been studies concentrating on the correlation between serum C‐reactive protein (CRP) level and COVID‐19 severity but we aim to reach a threshold for CRP in disease severity determination. Methods: We conducted a thorough search on PubMed, Web of Science and Google Scholar databases from early 2019 to October 2021, and 323 studies were assessed for eligibility in three phases. We used the Newcastle‐Ottawa Scale to examine the validity of the studies. The t‐test was applied for the CRP level cutoffs. Results: Eventually, 11 articles and 1615 patients were included in this systematic review. Our analysis evaluated combined mean, median, and standard deviation of severe patients' CRP to be respectively 73.37, 53.80, and 47.936. Based on the combined mean, 75 mg/dL was suggested as an initial threshold for baseline CRP in hospitalized patients for developing severe conditions. Conclusion: This study recommends that COVID‐19 patients with on‐admission serum CRP levels of 75 mg/dL and more are likely associated with severe conditions. Thus, anti‐inflammatory agents and further following may be helpful in these patients. [ABSTRACT FROM AUTHOR]

Aims: Patients with heart failure (HF) exhibit poor prognosis, which is further deteriorated by pulmonary hypertension (PH), with negative impact on morbidity and mortality. As PH due to left HF (LHF‐PH) is among the most common causes of PH, there is an urge according to the 2021 European Society of Cardiology HF guidelines to find new biomarkers that aid in prognostication of this patient cohort. Given the role of tumour necrosis factor‐alpha (TNF‐α) in HF progression, we aimed to investigate the prognostic value of plasma proteins related to TNF‐α in patients with LHF‐PH, in relation to haemodynamic changes following heart transplantation (HT). Methods and results: Twenty TNF‐α‐related plasma proteins were analysed using proximity extension assay in healthy controls (n = 20) and patients with LHF‐PH (n = 67), before and 1 year after HT (n = 19). Plasma levels were compared between the groups, and the prognostic values were determined using Kaplan–Meier and Cox regression analyses. Plasma levels of lymphotoxin‐beta receptor (LTBR), TNF receptor superfamily member 6B (TNFRSF6B), and TNF‐related apoptosis‐inducing ligand receptors 1 and 2 (TRAIL‐R1 and TRAIL‐R2, respectively) were higher in LHF‐PH pre‐HT vs. controls (P < 0.0001), as well as higher in pre‐HT vs. post‐HT (P < 0.001). The elevated pre‐HT levels of LTBR, TNFRSF6B, TRAIL‐R1, and TRAIL‐R2 decreased towards the levels of healthy controls after HT. Higher preoperative levels of LTBR, TNFRSF6B, TRAIL‐R1, and TRAIL‐R2 in LHF‐PH were associated with worse survival rates (P < 0.002). In multivariate Cox regression models, each adjusted for age and sex, LTBR, TNFRSF6B, TRAIL‐R1, and TRAIL‐R2 predicted mortality (P < 0.002) [hazard ratio (95% confidence interval): 1.12 (1.04–1.19), 1.01 (1.004–1.02), 1.28 (1.14–1.42), and 1.03 (1.02–1.04), respectively]. Conclusions: Elevated pre‐HT plasma levels of the TNF‐α‐related proteins LTBR, TNFRSF6B, TRAIL‐R1, and TRAIL‐R2 in LHF‐PH decreased 1 year after HT, displaying a normalization pattern towards the levels of the healthy controls. These proteins were also prognostic, where higher levels were associated with worse survival rates in LHF‐PH, providing new insight in their potential role as prognostic biomarkers. Larger studies are warranted to validate our findings and to investigate their possible pathobiological mechanisms in LHF‐PH. [ABSTRACT FROM AUTHOR]

Within the last decade new technologies have been developed and implemented which employ light, often in the presence of a photosensitizer, to inactivate pathogens that reside in human blood products for the purpose of transfusion. These pathogen reduction technologies attempt to find the proper balance between pathogen kill and cell quality. Each system utilizes various chemistries that not only impact which pathogens they can inactivate and how, but also how the treatments affect the plasma and cellular proteins and to what degree. This paper aims to present the various chemical mechanisms for pathogen reduction in transfusion medicine that are currently practiced or in development. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER), catalysed by proteins at mercury electrodes and reflected in chronopotentiometric stripping peak H, provides a label-free and reagentless analytical technique that is sensitive to protein structure. Here we show how the kinetic isotope effect affected the HER catalysed by the protein bovine serum albumin (BSA). We found that the deuteron bond, which is stronger than that of a proton, contributed to less effective transport of deuterons mediated by BSA at the HgjD2O interface, and enhanced structural stability of the surface-attached native BSA in D2O solution. A structural transition was also observed in the surface-attached urea-denatured BSA, and is probably due to the destabilisation of some secondary structural remnants retained by the 17 SSbonds. Because the catalytically active groups involved in proton or deuteron transfer in native proteins are often exposed towards solutions and their protons exchange almost instantly, no signs of H/D exchange were observed in native BSA using peak H under the given conditions. [ABSTRACT FROM AUTHOR]

Background: During sepsis, higher plasma cell-free hemoglobin (CFH) levels portend worse outcomes. In sepsis models, plasma proteins that bind CFH improve survival. In our canine antibiotic-treated Staphylococcus aureus pneumonia model, with and without red blood cell (RBC) exchange transfusion, commercial human haptoglobin (Hp) concentrates bound and compartmentalized CFH intravascularly, increased CFH clearance, and lowered iron levels, improving shock, lung injury, and survival. We now investigate in our model how very high CFH levels and treatment time affect Hp's beneficial effects.Materials and Methods: Two separate canine pneumonia sepsis Hp studies were undertaken: one with exchange transfusion of RBCs after prolonged storage to raise CFH to very high levels and another with rapidly lethal sepsis alone to shorten time to treat. All animals received continuous standard intensive care unit supportive care for 96 hours.Results: Older RBCs markedly elevated plasma CFH levels and, when combined with Hp therapy, created supraphysiologic CFH-Hp complexes that did not increase CFH or iron clearance or improve lung injury and survival. In a rapidly lethal bacterial challenge model without RBC transfusion, Hp binding did not increase clearance of complexes or iron or show benefits seen previously in the less lethal model.Discussion: High-level CFH-Hp complexes may impair clearance mechanisms and eliminate Hp's beneficial effect during sepsis. Rapidly lethal sepsis narrows the therapeutic window for CFH and iron clearance, also decreasing Hp's beneficial effects. In designing clinical trials, dosing and kinetics may be critical factors if Hp infusion is used to treat sepsis. [ABSTRACT FROM AUTHOR]

β2‐microglobulin (β2‐m) is a plasma protein derived from physiological shedding of the class I major histocompatibility complex (MHCI), causing human systemic amyloidosis either due to persistently high concentrations of the wild‐type (WT) protein in hemodialyzed patients, or in presence of mutations, such as D76N β2‐m, which favor protein deposition in the adulthood, despite normal plasma levels. Here we describe a new transgenic Caenorhabditis elegans (C. elegans) strain expressing human WT β2‐m at high concentrations, mimicking the condition that underlies dialysis‐related amyloidosis (DRA) and we compare it to a previously established strain expressing the highly amyloidogenic D76N β2‐m at lower concentrations. Both strains exhibit behavioral defects, the severity of which correlates with β2‐m levels rather than with the presence of mutations, being more pronounced in WT β2‐m worms. β2‐m expression also has a deep impact on the nematodes' proteomic and metabolic profiles. Most significantly affected processes include protein degradation and stress response, amino acids metabolism, and bioenergetics. Molecular alterations are more pronounced in worms expressing WT β2‐m at high concentration compared to D76N β2‐m worms. Altogether, these data show that β2‐m is a proteotoxic protein in vivo also in its wild‐type form, and that concentration plays a key role in modulating pathogenicity. Our transgenic nematodes recapitulate the distinctive features subtending DRA compared to hereditary β2‐m amyloidosis (high levels of non‐mutated β2‐m vs. normal levels of variant β2‐m) and provide important clues on the molecular bases of these human diseases. [ABSTRACT FROM AUTHOR]

Proteomic approaches have unique advantages in the identification of biological pathways that influence physical frailty, a multifactorial geriatric syndrome predictive of adverse health outcomes in older adults. To date, proteomic studies of frailty are scarce, and few evaluated prefrailty as a separate state or examined predictors of incident frailty. Using plasma proteins measured by 4955 SOMAmers in the Atherosclerosis Risk in Community study, we identified 134 and 179 proteins cross‐sectionally associated with prefrailty and frailty, respectively, after Bonferroni correction (p < 1 × 10−5) among 3838 older adults aged ≥65 years, adjusting for demographic and physiologic factors and chronic diseases. Among them, 23 (17%) and 82 (46%) were replicated in the Cardiovascular Health Study using the same models (FDR p < 0.05). Notably, higher odds of prefrailty and frailty were observed with higher levels of growth differentiation factor 15 (GDF15; pprefrailty = 1 × 10−15, pfrailty = 2 × 10−19), transgelin (TAGLN; pprefrailty = 2 × 10−12, pfrailty = 6 × 10−22), and insulin‐like growth factor‐binding protein 2 (IGFBP2; pprefrailty = 5 × 10−15, pfrailty = 1 × 10−15) and with a lower level of growth hormone receptor (GHR, pprefrailty = 3 × 10−16, pfrailty = 2 × 10−18). Longitudinally, we identified 4 proteins associated with incident frailty (p < 1 × 10−5). Higher levels of triggering receptor expressed on myeloid cells 1 (TREM1), TAGLN, and heart and adipocyte fatty‐acid binding proteins predicted incident frailty. Differentially regulated proteins were enriched in pathways and upstream regulators related to lipid metabolism, angiogenesis, inflammation, and cell senescence. Our findings provide a set of plasma proteins and biological mechanisms that were dysregulated in both the prodromal and the clinical stage of frailty, offering new insights into frailty etiology and targets for intervention. [ABSTRACT FROM AUTHOR]

Diet can affect the inflammatory state of the body. Accordingly, the dietary inflammatory index (DII) has been developed to quantify the inflammatory properties of food items. This study sought to investigate the association between dietary inflammation index (DII) and the odds ratio of elevated CRP (E‐CRP) through a systematic review and meta‐analysis study. The International electronic databases of PubMed, Web of Science (ISI), and Scopus were searched until May 2023 to find related articles. From 719 studies found in the initial search, 14 studies, with a total sample size of 59,941 individuals, were included in the meta‐analysis. The calculated pooled odds ratio (OR) of E‐CRP in the highest DII category was 1.39 (95% CI: 1.06, 1.14, test for heterogeneity: p =.63, and I2 =.0%) in comparison with the lowest DII category. Also, the results of this study showed that each unit increase in DII as a continuous variable generally elicited a 10% increase in the odds of E‐CRP (OR 1.10, 95% CI 1.06, 1.14, test for heterogeneity: p =.63, and I2 =.0%). Subgroup meta‐analyses showed that there is a higher E‐CRP odds ratio for the articles that reported energy‐adjusted DII (E‐DII) instead of DII, the studies that measured CRP instead of hs‐CRP, and the studies that used 24‐h recall instead of FFQ as the instrument of dietary intake data collection. Individuals with a higher DII were estimated to have higher chances of developing elevated serum CRP. This value was influenced by factors such as the participants' nationality, instruments of data collection, methods used to measure inflammatory biomarkers, study design, and data adjustments. However, future well‐designed studies can help provide a more comprehensive understanding of the inflammatory properties of diet and inflammatory serum biomarkers. [ABSTRACT FROM AUTHOR]

Background: Attainment of adequate transfer of passive immunity (TPI) is critical to health of calves; however, studies comparing available tools for measurement of TPI in individual beef animals are limited. Objectives: To report agreement between 4 tests evaluating individual TPI status in beef calves. Animals: One hundred ninety‐six beef calves born to cows and heifers presenting for calving management or dystocia. Methods: Retrospective study to assess serum immunoglobulin (IgG) concentrations via turbidimetric immunoassay (TI), gamma‐glutamyl transferase (GGT), serum total protein (TP), and single radial immunodiffusion (RID; reference standard). Test agreement was evaluated using Passing‐Bablok regression, Bland‐Altman analysis, Cohen's kappa, and receiver operating characteristic (ROC) curves with and without covariate adjustment to determine optimal thresholds. Results: Correlation between RID and test results varied: TI, ρ = 0.757; TP, ρ = 0.715; GGT: ρ = 0.413. For the TI compared to RID, regression analysis identified a constant (intercept = −0.51 [CI: −2.63, 3.05]) and proportional (slope = 1.87 [CI: 1.69, 2.08]) bias. Based on ROC, TI concentrations of ≤9.89 and ≤13.76 g/L, and TP concentrations of ≤5.5 and ≤6.0 g/dL, indicated IgG concentrations <18.0 and <25.0 g/L, respectively. Conclusions and Clinical Importance: Within this cohort of calves, TI demonstrated the best correlation with RID; however, significant bias was identified which led to frequent underestimation of IgG concentration. Serum total protein demonstrated less correlation with RID but had less misclassification than TI. Both TI and TP demonstrated less correlation for calves that received colostrum replacement prompting clinical awareness of colostrum type when evaluating individual TPI in beef calves. [ABSTRACT FROM AUTHOR]

RATIONALE Liquid chromatography/tandem mass spectrometry (LC/MS/MS) assays are increasingly being used for absolute quantitation of proteins due to high specificity and low cost. However, the major challenge for the LC/MS method is insufficient sensitivity. This paper details the strategies developed to maximize the sensitivity from aspects of chromatography, mass spectrometry, and sample preparation to achieve a highly sensitive LC/MS method. METHODS The method is based on the LC/MS/MS measurement of a surrogate peptide generated from trypsin digestion of interferon-gamma-inducible protein-10 (IP-10). The sample preparation strategy involved selectively extracting IP-10 and removing high-abundance serum proteins through acidified protein precipitation (PPT). It was revealed in this work that these high-abundance serum proteins, if not separated from the protein of interest, could cause significant ionization saturation and high background noise in selected reaction monitoring (SRM), leading to a 100-fold higher lower limit of quantification (LLOQ). RESULTS Our method demonstrated that the acidified PPT could be optimized to selectively extract the protein of interest with full recovery of 97% to 103%, while the high-abundance serum proteins could be effectively removed with minimal matrix effect of 90% to 93%. For the first time, a highly sensitive LC/MS method with a LLOQ of 31.62 pM for the quantitation of IP-10 has been achieved, which is a 100-fold improvement over the generic method. CONCLUSIONS The described method offers excellent sensitivity with advantages of being antibody reagent independent and leads to significant cost and time savings. It has been successfully employed to determine both total and free IP-10 levels in human serum samples. This method development strategy may also be applied to other small proteins. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The endothelial glycocalyx is an important part of the vascular barrier. The glycocalyx is intimately linked to the homoeostatic functions of the endothelium. Damage to the glycocalyx precedes vascular pathology. In the first part of this paper, we have reviewed the structure, physiology and pathology of the endothelial glycocalyx, based on a literature search of the past five years. In the second part, we have systematically reviewed interventions to protect or repair the glycocalyx. Glycocalyx damage can be caused by hypervolaemia and hyperglycaemia and can be prevented by maintaining a physiological concentration of plasma protein, particularly albumin. Other interventions have been investigated in animal models: these require clinical research before their introduction into medical practice. [ABSTRACT FROM AUTHOR]