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1.
PLoS Pathog ; 19(7): e1011529, 2023 07.
Article in English | MEDLINE | ID: mdl-37478143

ABSTRACT

The genomes of positive-sense RNA viruses encode polyproteins that are essential for mediating viral replication. These viral polyproteins must undergo proteolysis (also termed polyprotein processing) to generate functional protein units. This proteolysis can be performed by virally-encoded proteases as well as host cellular proteases, and is generally believed to be a key step in regulating viral replication. Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis. The positive-sense RNA genome is translated to generate a polyprotein, termed pORF1, which is necessary and sufficient for viral genome replication. However, the mechanism of polyprotein processing in HEV remains to be determined. In this study, we aimed to understand processing of this polyprotein and its role in viral replication using a combination of in vitro translation experiments and HEV sub-genomic replicons. Our data suggest no evidence for a virally-encoded protease or auto-proteolytic activity, as in vitro translation predominantly generates unprocessed viral polyprotein precursors. However, seven cleavage sites within the polyprotein (suggested by bioinformatic analysis) are susceptible to the host cellular protease, thrombin. Using two sub-genomic replicon systems, we demonstrate that mutagenesis of these sites prevents replication, as does pharmacological inhibition of serine proteases including thrombin. Overall, our data supports a model where HEV uses host proteases to support replication and could have evolved to be independent of a virally-encoded protease for polyprotein processing.


Subject(s)
Hepatitis E virus , Hepatitis E virus/genetics , Polyproteins/genetics , Polyproteins/metabolism , Thrombin , Virus Replication/physiology , Peptide Hydrolases/genetics , Peptide Hydrolases/metabolism , Viral Nonstructural Proteins/metabolism
2.
Ann Rheum Dis ; 82(3): 428-437, 2023 03.
Article in English | MEDLINE | ID: mdl-36414376

ABSTRACT

OBJECTIVES: Fibroblasts in synovium include fibroblast-like synoviocytes (FLS) in the lining and Thy1+ connective-tissue fibroblasts in the sublining. We aimed to investigate their developmental origin and relationship with adult progenitors. METHODS: To discriminate between Gdf5-lineage cells deriving from the embryonic joint interzone and other Pdgfrα-expressing fibroblasts and progenitors, adult Gdf5-Cre;Tom;Pdgfrα-H2BGFP mice were used and cartilage injury was induced to activate progenitors. Cells were isolated from knees, fibroblasts and progenitors were sorted by fluorescence-activated cell-sorting based on developmental origin, and analysed by single-cell RNA-sequencing. Flow cytometry and immunohistochemistry were used for validation. Clonal-lineage mapping was performed using Gdf5-Cre;Confetti mice. RESULTS: In steady state, Thy1+ sublining fibroblasts were of mixed ontogeny. In contrast, Thy1-Prg4+ lining fibroblasts predominantly derived from the embryonic joint interzone and included Prg4-expressing progenitors distinct from molecularly defined FLS. Clonal-lineage tracing revealed compartmentalisation of Gdf5-lineage fibroblasts between lining and sublining. Following injury, lining hyperplasia resulted from proliferation and differentiation of Prg4-expressing progenitors, with additional recruitment of non-Gdf5-lineage cells, into FLS. Consistent with this, a second population of proliferating cells, enriched near blood vessels in the sublining, supplied activated multipotent cells predicted to give rise to Thy1+ fibroblasts, and to feed into the FLS differentiation trajectory. Transcriptional programmes regulating fibroblast differentiation trajectories were uncovered, identifying Sox5 and Foxo1 as key FLS transcription factors in mice and humans. CONCLUSIONS: Our findings blueprint a cell atlas of mouse synovial fibroblasts and progenitors in healthy and injured knees, and provide novel insights into the cellular and molecular principles governing the organisation and maintenance of adult synovial joints.


Subject(s)
Receptor, Platelet-Derived Growth Factor alpha , Synoviocytes , Humans , Adult , Mice , Animals , Joints , Synovial Membrane , Fibroblasts
3.
BMC Infect Dis ; 23(1): 458, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37430196

ABSTRACT

INTRODUCTION: The rate of community antibiotic use is high in Aotearoa New Zealand (NZ) when compared to other nations, and in NZ, as in most other nations, antibiotics are very commonly prescribed for self-limiting upper respiratory tract infections (URTIs). Resources that build knowledge, perceptions and understanding can potentially reduce unnecessary antibiotic consumption. METHODS: To inform the content of educational resources, we conducted an in-depth qualitative study with 47 participants via 6 focus groups of the knowledge, attitudes, and expectations of whanau Maori and Pacific peoples about antibiotics and URTIs. RESULTS: Focus groups with 47 participants identified four themes: Knowledge that might influence expectations to receive antibiotics for URTIs; Perceptions - the factors that influence when and why to seek medical care for URTI; Expectations - the features of successful medical care for URTI; Solutions - how to build community knowledge about URTI and their treatment and prevention. Knowledge that might reduce expectations to receive antibiotics for URTI included confidence in the use of alternative remedies, knowledge that URTI are usually caused by viruses, and concerns about antibiotic adverse effects. Participants commonly reported that they would confidently accept their doctor's recommendation that an antibiotic was not necessary for an URTI, provided that a thorough assessment had been performed and that treatment decisions were clearly communicated. CONCLUSION: These findings suggest that building patients' knowledge and skills about when antibiotics are necessary, and increasing doctors' confidence and willingness not to prescribe an antibiotic for patients with an URTI, could significantly reduce inappropriate antibiotic prescribing in NZ.


Subject(s)
Anti-Bacterial Agents , Health Knowledge, Attitudes, Practice , Maori People , Respiratory Tract Infections , Humans , Anti-Bacterial Agents/therapeutic use , Focus Groups , Motivation , Qualitative Research , Respiratory Tract Infections/drug therapy
4.
Ann Rheum Dis ; 81(2): 214-224, 2022 02.
Article in English | MEDLINE | ID: mdl-34844926

ABSTRACT

OBJECTIVE: We aimed to understand the role of the transcriptional co-factor Yes-associated protein (Yap) in the molecular pathway underpinning the pathogenic transformation of synovial fibroblasts (SF) in rheumatoid arthritis (RA) to become invasive and cause joint destruction. METHODS: Synovium from patients with RA and mice with antigen-induced arthritis (AIA) was analysed by immunostaining and qRT-PCR. SF were targeted using Pdgfrα-CreER and Gdf5-Cre mice, crossed with fluorescent reporters for cell tracing and Yap-flox mice for conditional Yap ablation. Fibroblast phenotypes were analysed by flow cytometry, and arthritis severity was assessed by histology. Yap activation was detected using Yap-Tead reporter cells and Yap-Snail interaction by proximity ligation assay. SF invasiveness was analysed using matrigel-coated transwells. RESULTS: Yap, its binding partner Snail and downstream target connective tissue growth factor were upregulated in hyperplastic human RA and in mouse AIA synovium, with Yap detected in SF but not macrophages. Lineage tracing showed polyclonal expansion of Pdgfrα-expressing SF during AIA, with predominant expansion of the Gdf5-lineage SF subpopulation descending from the embryonic joint interzone. Gdf5-lineage SF showed increased expression of Yap and adopted an erosive phenotype (podoplanin+Thy-1 cell surface antigen-), invading cartilage and bone. Conditional ablation of Yap in Gdf5-lineage cells or Pdgfrα-expressing fibroblasts ameliorated AIA. Interleukin (IL)-6, but not tumour necrosis factor alpha (TNF-α) or IL-1ß, Jak-dependently activated Yap and induced Yap-Snail interaction. SF invasiveness induced by IL-6 stimulation or Snail overexpression was prevented by Yap knockdown, showing a critical role for Yap in SF transformation in RA. CONCLUSIONS: Our findings uncover the IL-6-Yap-Snail signalling axis in pathogenic SF in inflammatory arthritis.


Subject(s)
Arthritis, Rheumatoid/pathology , Fibroblasts/pathology , Synovial Membrane/pathology , YAP-Signaling Proteins/metabolism , Animals , Arthritis, Experimental/pathology , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Fibroblasts/metabolism , Humans , Interleukin-6/metabolism , Mice , Signal Transduction/physiology , Snail Family Transcription Factors/metabolism , Synovial Membrane/metabolism
5.
Semin Thromb Hemost ; 48(2): 174-187, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34428799

ABSTRACT

Fibrinogen, one of the most abundant plasma proteins playing a key role in hemostasis, is an important modulator of wound healing and host defense against microbes. In the current review, we address the role of fibrin(ogen) throughout the process of wound healing and subsequent tissue repair. Initially fibrin(ogen) acts as a provisional matrix supporting incoming leukocytes and acting as reservoir for growth factors. It later goes on to support re-epithelialization, angiogenesis, and fibroplasia. Importantly, removal of fibrin(ogen) from the wound is essential for wound healing to progress. We also discuss how fibrin(ogen) functions through several mechanisms to protect the host against bacterial infection by providing a physical barrier, entrapment of bacteria in fibrin(ogen) networks, and by directing immune cell function. The central role of fibrin(ogen) in defense against bacterial infection has made it a target of bacterial proteins, evolved to interact with fibrin(ogen) to manipulate clot formation and degradation for the purpose of promoting microbial virulence and survival. Further understanding of the dual roles of fibrin(ogen) in wound healing and infection could provide novel means of therapy to improve recovery from surgical or chronic wounds and help to prevent infection from highly virulent bacterial strains, including those resistant to antibiotics.


Subject(s)
Fibrin , Fibrinogen , Estrone/analogs & derivatives , Fibrin/metabolism , Fibrinogen/metabolism , Humans , Infection Control , Wound Healing
6.
Arterioscler Thromb Vasc Biol ; 41(9): 2370-2383, 2021 09.
Article in English | MEDLINE | ID: mdl-34261330

ABSTRACT

Thrombosis is a major complication of cardiovascular disease, leading to myocardial infarction, acute ischemic stroke, or venous thromboembolism. Thrombosis occurs when a thrombus forms inside blood vessels disrupting blood flow. Developments in thrombectomy to remove thrombi from vessels have provided new opportunities to study thrombus composition which may help to understand mechanisms of disease and underpin improvements in treatments. We aimed to review thrombus compositions, roles of components in thrombus formation and stability, and methods to investigate thrombi. Also, we summarize studies on thrombus structure obtained from cardiovascular patients and animal models. Thrombi are composed of fibrin, red blood cells, platelets, leukocytes, and neutrophil extracellular traps. These components have been analyzed by several techniques, including scanning electron microscopy, laser scanning confocal microscopy, histochemistry, and immunohistochemistry; however, each technique has advantages and limitations. Thrombi are heterogenous in composition, but overall, thrombi obtained from myocardial infarction are composed of mainly fibrin and other components, including platelets, red blood cells, leukocytes, and cholesterol crystals. Thrombi from patients with acute ischemic stroke are characterized by red blood cell- and platelet-rich regions. Thrombi from patients with venous thromboembolism contain mainly red blood cells and fibrin with some platelets and leukocytes. Thrombus composition from patients with myocardial infarction is influenced by ischemic time. Animal thrombosis models are crucial to gain further mechanistic information about thrombosis and thrombus structure, with thrombi being similar in composition compared with those from patients. Further studies on thrombus composition and function are key to improve treatment and clinical outcome of thrombosis.


Subject(s)
Blood Coagulation , Blood Platelets/metabolism , Erythrocytes/metabolism , Fibrin/metabolism , Thrombosis/metabolism , Animals , Blood Platelets/pathology , Cholesterol/metabolism , Disease Models, Animal , Erythrocytes/pathology , Humans , Leukocytes/metabolism , Thrombectomy , Thrombosis/pathology , Thrombosis/therapy
7.
Sensors (Basel) ; 22(18)2022 Sep 15.
Article in English | MEDLINE | ID: mdl-36146344

ABSTRACT

Dexterous manipulation in robotic hands relies on an accurate sense of artificial touch. Here we investigate neuromorphic tactile sensation with an event-based optical tactile sensor combined with spiking neural networks for edge orientation detection. The sensor incorporates an event-based vision system (mini-eDVS) into a low-form factor artificial fingertip (the NeuroTac). The processing of tactile information is performed through a Spiking Neural Network with unsupervised Spike-Timing-Dependent Plasticity (STDP) learning, and the resultant output is classified with a 3-nearest neighbours classifier. Edge orientations were classified in 10-degree increments while tapping vertically downward and sliding horizontally across the edge. In both cases, we demonstrate that the sensor is able to reliably detect edge orientation, and could lead to accurate, bio-inspired, tactile processing in robotics and prosthetics applications.


Subject(s)
Robotics , Touch Perception , Neural Networks, Computer , Touch
8.
Blood ; 133(11): 1233-1244, 2019 03 14.
Article in English | MEDLINE | ID: mdl-30545831

ABSTRACT

Bleeding complications secondary to surgery, trauma, or coagulation disorders are important causes of morbidity and mortality. Although fibrin sealants are considered to minimize blood loss, this is not widely adopted because of its high cost and/or risk for infection. We present a novel methodology employing nonantibody fibrinogen-binding proteins, termed Affimers, to stabilize fibrin networks with the potential to control excessive bleeding. Two fibrinogen-specific Affimer proteins, F5 and G2, were identified and characterized for their effects on clot structure/fibrinolysis, using turbidimetric and permeation analyses and confocal and electron microscopy. Binding studies and molecular modeling identified interaction sites, whereas plasmin generation assays determined effects on plasminogen activation. In human plasma, F5 and G2 prolonged clot lysis time from 9.8 ± 1.1 minutes in the absence of Affimers to 172.6 ± 7.4 and more than 180 minutes (P < .0001), respectively, and from 7.6 ± 0.2 to 28.7 ± 5.8 (P < .05) and 149.3 ± 9.7 (P < .0001) minutes in clots made from purified fibrinogen. Prolongation in fibrinolysis was consistent across plasma samples from healthy control patients and individuals at high bleeding risk. F5 and G2 had a differential effect on clot structure and G2 profoundly altered fibrin fiber arrangement, whereas F5 maintained physiological clot structure. Affimer F5 reduced fibrin-dependent plasmin generation and was predicted to bind fibrinogen D fragment close to tissue plasminogen activator (tPA; residues γ312-324) and plasminogen (α148-160) binding sites, thus interfering with tPA-plasminogen interaction and representing 1 potential mechanism for modulation of fibrinolysis. Our Affimer proteins provide a novel methodology for stabilizing fibrin networks with potential future clinical implications to reduce bleeding risk.


Subject(s)
Blood Proteins/pharmacology , Fibrin Clot Lysis Time , Fibrinogen/metabolism , Fibrinolysis/drug effects , Thrombosis/prevention & control , Humans , Thrombosis/etiology , Tissue Plasminogen Activator/metabolism
9.
Qual Life Res ; 30(7): 1803-1832, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33738710

ABSTRACT

INTRODUCTION: Self-report is the gold standard for measuring children's health-related outcomes. Design of such measures is complex and challenging. This review aims to systematically appraise the evidence on recall period, response scale format, mode of administration and approaches needed to enable children and young people < 19 years to participate in valid and reliable self-reporting of their health outcomes. METHOD: PsycInfo, Medline, CINAHL and Embase were searched from 1 January 1990 to 15 March 2020, and citation searching undertaken in Scopus. Articles were included if they were primary research or case reports of ≥ 3 participants reporting the following: recall period, response scale selection, administration modality. Quality was assessed using QualSyst, and results synthesised narratively. This review was conducted and reported according to PRISMA guidelines. RESULTS: 81 of 13,215 retrieved articles met the inclusion criteria. Children < 5 years old cannot validly and reliably self-report health outcomes. Face scales demonstrate better psychometric properties than visual analogue or Likert scales. Computerised and paper scales generally show equivalent construct validity. Children prefer computerised measures. Children ≤ 7 years old think dichotomously so need two response options. Those > 8 years old can reliably use a 3-point scale. CONCLUSION: The results of this review have both clinical and research implications. They can be used to inform appropriate choice of PROM for use with CYP in the clinical setting. We also give eight recommendations for future development of self-reported outcome measures for children and young people.


Subject(s)
Outcome Assessment, Health Care/methods , Patient Reported Outcome Measures , Psychometrics/methods , Quality of Life/psychology , Child , Child, Preschool , Humans , Infant , Reproducibility of Results , Self Report
10.
Ann Rheum Dis ; 79(12): 1625-1634, 2020 12.
Article in English | MEDLINE | ID: mdl-32963046

ABSTRACT

OBJECTIVES: Osteophytes are highly prevalent in osteoarthritis (OA) and are associated with pain and functional disability. These pathological outgrowths of cartilage and bone typically form at the junction of articular cartilage, periosteum and synovium. The aim of this study was to identify the cells forming osteophytes in OA. METHODS: Fluorescent genetic cell-labelling and tracing mouse models were induced with tamoxifen to switch on reporter expression, as appropriate, followed by surgery to induce destabilisation of the medial meniscus. Contributions of fluorescently labelled cells to osteophytes after 2 or 8 weeks, and their molecular identity, were analysed by histology, immunofluorescence staining and RNA in situ hybridisation. Pdgfrα-H2BGFP mice and Pdgfrα-CreER mice crossed with multicolour Confetti reporter mice were used for identification and clonal tracing of mesenchymal progenitors. Mice carrying Col2-CreER, Nes-CreER, LepR-Cre, Grem1-CreER, Gdf5-Cre, Sox9-CreER or Prg4-CreER were crossed with tdTomato reporter mice to lineage-trace chondrocytes and stem/progenitor cell subpopulations. RESULTS: Articular chondrocytes, or skeletal stem cells identified by Nes, LepR or Grem1 expression, did not give rise to osteophytes. Instead, osteophytes derived from Pdgfrα-expressing stem/progenitor cells in periosteum and synovium that are descendants from the Gdf5-expressing embryonic joint interzone. Further, we show that Sox9-expressing progenitors in periosteum supplied hybrid skeletal cells to the early osteophyte, while Prg4-expressing progenitors from synovial lining contributed to cartilage capping the osteophyte, but not to bone. CONCLUSION: Our findings reveal distinct periosteal and synovial skeletal progenitors that cooperate to form osteophytes in OA. These cell populations could be targeted in disease modification for treatment of OA.


Subject(s)
Osteoarthritis/pathology , Osteophyte/pathology , Periosteum/pathology , Stem Cells/pathology , Synovial Membrane/pathology , Animals , Cell Lineage , Mice
11.
Am J Hematol ; 95(8): 944-952, 2020 08.
Article in English | MEDLINE | ID: mdl-32311169

ABSTRACT

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder, characterized by complement-mediated intravascular hemolysis and thrombosis. The increased incidence of PNH-driven thrombosis is still poorly understood, but unlike other thrombotic disorders, is thought to largely occur through complement-mediated mechanisms. Treatment with a C5 inhibitor, eculizumab, has been shown to significantly reduce the number of thromboembolic events in these patients. Based on previously described links between changes in fibrin clot structure and thrombosis in other disorders, our aim was to investigate clot structure as a possible mechanism of thrombosis in patients with PNH and the anti-thrombotic effects of eculizumab treatment on clot structure. Clot structure, fibrinogen levels and thrombin generation were examined in plasma samples from 82 patients from the National PNH Service in Leeds, UK. Untreated PNH patients were found to have increased levels of fibrinogen and thrombin generation, with subsequent prothrombotic changes in clot structure. No link was found between increasing disease severity and fibrinogen levels, thrombin generation, clot formation or structure. However, eculizumab treated patients showed decreased fibrinogen levels, thrombin generation and clot density, with increasing time spent on treatment augmenting these antithrombotic effects. These data suggest that PNH patients have a prothrombotic clot phenotype due to increased fibrinogen levels and thrombin generation, and that the antithrombotic effects of eculizumab are, in-part, due to reductions in fibrinogen and thrombin generation with downstream effects on clot structure.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Blood Coagulation/drug effects , Complement Inactivating Agents/therapeutic use , Hemoglobinuria, Paroxysmal/cerebrospinal fluid , Hemoglobinuria, Paroxysmal/drug therapy , Antibodies, Monoclonal, Humanized/pharmacology , Complement Inactivating Agents/pharmacology , Female , Healthy Volunteers , Hemoglobinuria, Paroxysmal/complications , Humans , Male , Phenotype
12.
BMC Plant Biol ; 19(1): 172, 2019 Apr 30.
Article in English | MEDLINE | ID: mdl-31039740

ABSTRACT

BACKGROUND: Angiosperm sex chromosomes, where present, are generally recently evolved. The key step in initiating the development of sex chromosomes from autosomes is the establishment of a sex-determining locus within a region of non-recombination. To better understand early sex chromosome evolution, it is important to determine the process by which recombination is suppressed around the sex determining genes. We have used the dioecious angiosperm kiwifruit Actinidia chinensis var. chinensis, which has an active-Y sex chromosome system, to study recombination rates around the sex locus, to better understand key events in the development of sex chromosomes. RESULTS: We have confirmed the sex-determining region (SDR) in A. chinensis var. chinensis, using a combination of high density genetic mapping and fluorescent in situ hybridisation (FISH) of Bacterial Artificial Chromosomes (BACs) linked to the sex markers onto pachytene chromosomes. The SDR is a subtelomeric non-recombining region adjacent to the nucleolar organiser region (NOR). A region of restricted recombination of around 6 Mbp in size in both male and female maps spans the SDR and covers around a third of chromosome 25. CONCLUSIONS: As recombination is suppressed over a similar region between X chromosomes and between and X and Y chromosomes, we propose that recombination is suppressed in this region because of the proximity of the NOR and the centromere, with both the NOR and centromere suppressing recombination, and this predates suppressed recombination due to differences between X and Y chromosomes. Such regions of suppressed recombination in the genome provide an opportunity for the evolution of sex chromosomes, if a sex-determining locus develops there or translocates into this region.


Subject(s)
Actinidia/genetics , Chromosomes, Plant , Recombination, Genetic , Sex Chromosomes , Actinidia/cytology , Chromosome Mapping , Chromosomes, Artificial, Bacterial , Genetic Variation , In Situ Hybridization, Fluorescence , Microsatellite Repeats
13.
BMC Musculoskelet Disord ; 20(1): 326, 2019 Jul 12.
Article in English | MEDLINE | ID: mdl-31299941

ABSTRACT

BACKGROUND: Oestrogen-deficiency induced by menopause is associated with reduced bone density and primary osteoporosis, resulting in an increased risk of fracture. While the exact etiology of menopause-induced primary osteoporotic bone loss is not fully known, members of the tumour necrosis factor super family (TNFSF) are known to play a role. Recent studies have revealed that the TNFSF members death receptor 3 (DR3) and one of its ligands, TNF-like protein 1A (TL1A) have a key role in secondary osteoporosis; enhancing CD14+ peripheral blood mononuclear cell (PBMC) osteoclast formation and bone resorption. Whether DR3 and TL1A contribute towards bone loss in menopause-induced primary osteoporosis however, remains unknown. METHODS: To investigate this we performed flow cytometry analysis of DR3 expression on CD14+ PBMCs isolated from pre- and early post-menopausal females and late post-menopausal osteoporotic patients. Serum levels of TL1A, CCL3 and total MMP-9 were measured by ELISA. In vitro osteoclast differentiation assays were performed to determine CD14+ monocyte osteoclastogenic potential. In addition, splenic CD4+ T cell DR3 expression was investigated 1 week and 8 weeks post-surgery, using the murine ovariectomy model. RESULTS: In contrast to pre-menopausal females, CD14+ monocytes isolated from post-menopausal females were unable to induce DR3 expression. Serum TL1A levels were decreased approx. 2-fold in early post-menopausal females compared to pre-menopausal controls and post-menopausal osteoporotic females; no difference was observed between pre-menopausal and late post-menopausal osteoporotic females. Analysis of in vitro CD14+ monocyte osteoclastogenic potential revealed no significant difference between the post-menopausal and post-menopausal osteoporotic cohorts. Interestingly, in the murine ovariectomy model splenic CD4+ T cell DR3 expression was significantly increased at 1 week but not 8 weeks post-surgery when compared to the sham control. CONCLUSION: Our results reveals for the first time that loss of oestrogen has a significant effect on DR3; decreasing expression on CD14+ monocytes and increasing expression on CD4+ T cells. These data suggest that while oestrogen-deficiency induced changes in DR3 expression do not affect late post-menopausal bone loss they could potentially have an indirect role in early menopausal bone loss through the modulation of T cell activity.


Subject(s)
Estrogens/deficiency , Osteoporosis, Postmenopausal/metabolism , Receptors, Tumor Necrosis Factor, Member 25/metabolism , Tumor Necrosis Factor Ligand Superfamily Member 15/blood , Adult , Aged , Animals , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Disease Models, Animal , Female , Humans , Lipopolysaccharide Receptors/metabolism , Menopause/blood , Menopause/physiology , Mice , Middle Aged , Monocytes/immunology , Monocytes/metabolism , Osteoporosis, Postmenopausal/blood , Osteoporosis, Postmenopausal/immunology , Ovariectomy , Young Adult
14.
Blood ; 127(4): 487-95, 2016 Jan 28.
Article in English | MEDLINE | ID: mdl-26608329

ABSTRACT

Previous studies have shown effects of thrombin and fibrinogen γ' on clot structure. However, structural information was obtained using electron microscopy, which requires sample dehydration. Our aim was to investigate the role of thrombin and fibrinogen γ' in modulating fibrin structure under fully hydrated conditions. Fibrin fibers were studied using turbidimetry, atomic force microscopy, electron microscopy, and magnetic tweezers in purified and plasma solutions. Increased thrombin induced a pronounced decrease in average protofibril content per fiber, with a relatively minor decrease in fiber size, leading to the formation of less compact fiber structures. Atomic force microscopy under fully hydrated conditions confirmed that fiber diameter was only marginally decreased. Decreased protofibril content of the fibers produced by high thrombin resulted in weakened clot architecture as analyzed by magnetic tweezers in purified systems and by thromboelastometry in plasma and whole blood. Fibers produced with fibrinogen γ' showed reduced protofibril packing over a range of thrombin concentrations. High-magnification electron microscopy demonstrated reduced protofibril packing in γ' fibers and unraveling of fibers into separate protofibrils. Decreased protofibril packing was confirmed in plasma for high thrombin concentrations and fibrinogen-deficient plasma reconstituted with γ' fibrinogen. These findings demonstrate that, in fully hydrated conditions, thrombin and fibrinogen γ' have dramatic effects on protofibril content and that protein density within fibers correlates with strength of the fibrin network. We conclude that regulation of protofibril content of fibers is an important mechanism by which thrombin and fibrinogen γ' modulate fibrin clot structure and strength.


Subject(s)
Blood Coagulation , Fibrinogens, Abnormal/metabolism , Fibrinogens, Abnormal/ultrastructure , Thrombin/metabolism , Thrombin/ultrastructure , Blood Viscosity , Humans , Microscopy, Atomic Force , Nephelometry and Turbidimetry , Thrombosis/metabolism
15.
Haematologica ; 103(1): 9-17, 2018 01.
Article in English | MEDLINE | ID: mdl-29246924

ABSTRACT

Paroxysmal nocturnal hemoglobinuria is a rare acquired hematologic disorder, the most serious complication of which is thrombosis. The increased incidence of thrombosis in paroxysmal nocturnal hemoglobinuria is still poorly understood, but unlike many other thrombotic disorders, predominantly involves complement-mediated mechanisms. This review article discusses the different factors that contribute to the increased risk of thrombosis in paroxysmal nocturnal hemoglobinuria. Paroxysmal nocturnal hemoglobinuria leads to a complex and multifaceted prothrombotic state due to the pathological effects of platelet activation, intravascular hemolysis and neutrophil/monocyte activation. Platelet and endothelial microparticles as well as oxidative stress may play a role. Impaired fibrinolysis has also been observed and may be caused by several mechanisms involving interactions between complement activation, coagulation and fibrinolysis. While many factors may affect thrombosis in paroxysmal nocturnal hemoglobinuria, the relative contribution of each mechanism that has been implicated is difficult to quantify. Further studies, including novel in vivo and in vitro thrombosis models, are required in order to define the role of the individual mechanisms contributing to thrombosis, impaired fibrinolysis and clarify other complement-driven prothrombotic mechanisms in paroxysmal nocturnal hemoglobinuria.


Subject(s)
Blood Coagulation , Hemoglobinuria, Paroxysmal/blood , Hemoglobinuria, Paroxysmal/etiology , Animals , Biomarkers , Blood Platelets/metabolism , Cell-Derived Microparticles/metabolism , Disease Models, Animal , Endothelium, Vascular/metabolism , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/pathology , Hemoglobins/metabolism , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/diagnosis , Humans , Phenotype , Platelet Activation , Reactive Oxygen Species , Thrombosis/blood , Thrombosis/etiology
16.
Int J Colorectal Dis ; 33(2): 231-234, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29188453

ABSTRACT

AIM: Enhanced recovery after surgery (ERAS) programmes and laparoscopic techniques both provide short-term benefits to patients undergoing colorectal cancer surgery. ERAS protocol compliance may improve long-term survival in those undergoing open colorectal resection but as laparoscopic data has not been reported. Therefore, we aimed to investigate the impact of the combination of laparoscopy and ERAS management on 5-year overall survival. METHODS: A dedicated prospectively populated colorectal cancer surgery database was reviewed. Patient inclusion criteria were biopsy-proven colorectal adenocarcinoma, undergoing elective surgery undertaken with curative intent. All patients were managed within an established ERAS programme and routinely followed up for 5 years. Overall survival was measured using the log-rank Kaplan-Meier method at 5 years. RESULTS: Eight hundred fifty-four patients met the inclusion criteria. Four hundred eighty-one (56%) cases were laparoscopic with 98 patients (20%) requiring conversion. There were no differences in patient or tumour demographics between the surgical groups. Median ERAS protocol compliance was 93% (range 53-100%). Five-year overall survival was superior in laparoscopic cases compared with that of converted and open surgery (78 vs 68 vs 70%, respectively, p < 0.007). An open approach (HR 1.55, 95%CI 1.16-2.06, p = 0.002) and delayed hospital discharge (> 7 days, HR 1.5, 95%CI 1.13-1.9, p = 0.003) were the only modifiable risk factors associated with poor survival. CONCLUSIONS: The use of a laparoscopic approach with enhanced recovery after surgery management appears to have long-term survival benefits following colorectal cancer resection.


Subject(s)
Colorectal Neoplasms/surgery , Colorectal Surgery , Laparoscopy , Recovery of Function , Follow-Up Studies , Humans , Kaplan-Meier Estimate
17.
Nanomedicine ; 14(3): 909-918, 2018 04.
Article in English | MEDLINE | ID: mdl-29410160

ABSTRACT

Plasma fibrinogen includes an alternatively spliced γ-chain variant (γ'), which mainly exists as a heterodimer (γAγ') and has been associated with thrombosis. We tested γAγ' fibrinogen-red blood cells (RBCs) interaction using atomic force microscopy-based force spectroscopy, magnetic tweezers, fibrin clot permeability, scanning electron microscopy and laser scanning confocal microscopy. Data reveal higher work necessary for RBC-RBC detachment in the presence of γAγ' rather than γAγA fibrinogen. γAγ' fibrinogen-RBCs interaction is followed by changes in fibrin network structure, which forms an heterogeneous clot structure with areas of denser and highly branched fibrin fibers. The presence of RBCs also increased the stiffness of γAγ' fibrin clots, which are less permeable and more resistant to lysis than γAγA clots. The modifications on clots promoted by RBCs-γAγ' fibrinogen interaction could alter the risk of thrombotic disorders.


Subject(s)
Blood Coagulation , Cell Adhesion , Erythrocytes/metabolism , Fibrin/metabolism , Fibrin/ultrastructure , Fibrinogen/metabolism , Fibrinogens, Abnormal/metabolism , Erythrocytes/ultrastructure , Fibrinogen/ultrastructure , Fibrinogens, Abnormal/ultrastructure , Hemostatics , Humans , Microscopy, Atomic Force , Microscopy, Electron, Scanning
18.
Clin Otolaryngol ; 43(1): 151-157, 2018 02.
Article in English | MEDLINE | ID: mdl-28620984

ABSTRACT

BACKGROUND: New cases of oropharyngeal squamous cell carcinoma (OPSCC) are routinely tested for HPV. HPV in saliva can be detected with PCR, but its clinical applicability in the context of OPSCC remains unknown. METHODS: Forty-six consecutive patients diagnosed with OPSCC had pre-treatment saliva specimens collected. PCR for HPV on saliva was compared to p16 IHC and HPV DNA in situ hybridisation (ISH) on surgical biopsies. RESULTS: The sensitivity and specificity of saliva testing when compared to the reference test of p16 IHC and HPV DNA ISH were 72.2% and 90%, and positive and negative predictive values were 96.3% and 47.4%. There were no adverse events. Time from last meal, smoking, alcohol drinking and physical exercise did not impact on results. CONCLUSIONS: Saliva testing is a promising test to detect HPV in patients with OPSCC. A positive result could avoid the need for surgical biopsies, thereby reducing costs, patient morbidity and expedite treatment.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , DNA, Viral/analysis , Oropharyngeal Neoplasms/diagnosis , Papillomaviridae/genetics , Papillomavirus Infections/diagnosis , Saliva/chemistry , Adult , Aged , Aged, 80 and over , Biopsy , Carcinoma, Squamous Cell/virology , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Oropharyngeal Neoplasms/virology , Papillomavirus Infections/virology , Polymerase Chain Reaction , Prospective Studies , Reproducibility of Results , Saliva/virology
19.
Pol J Vet Sci ; 21(2): 255-263, 2018 Jun.
Article in English | MEDLINE | ID: mdl-30450863

ABSTRACT

Lipoproteins, isolated from ostrich egg yolk (LPFo), provide excellent protection for boar spermatozoa against cryo-induced damage. The present study was performed to investigate the effects of LPFo on the freezability and fertilizing capacity of frozen-thawed (FT) boar semen after post-cervical artificial inseminations (post-CAIs). Semen, collected from 7 Polish Large White (PLW) and 4 Polish Landrace (PLR), was frozen in an extender containing LPFo. Post-CAIs were performed in 38 multiparous sows, using a catheter-cannula kit. Sows were inseminated 2× within one oestrus, and fertility parameters were recorded after farrowing. Neither boar (within breed) nor breed affected the quality of the pre-freeze (PF) semen, such as total motility (TMOT), mitochondria membrane potential (MMP), plasma membrane integrity (PMI), osmotic resistance test (ORT) and DNA fragmentation. Differences in the freezability of boar semen were observed among the boars, whereas there were no marked breed effects. Post-thaw TMOT markedly declined over storage time in most of the boars, particularly at 60 min after thawing. Inseminations of post-weaned oestrus sows resulted in pregnancy and farrowing rates of 84.2% and 81.6%, respectively. Neither the mean number of piglets born (NB) nor the mean number of piglets born alive (NBA) was affected by boar or breed. The total number of piglets born was 365, resulting in 11.8 NB piglets, whereas the total number of piglets born alive was 353, with 11.4 NBA piglets per litter. The findings of this study reaffirm the variations in the freezability of boar semen. In this study the supplementation of ostrich egg yolk lipoproteins to the freezing extender of boar semen produced high proportions of functionally viable FT spermatozoa that were capable of providing acceptable fertility results after post-CAIs in multiparous sows.


Subject(s)
Cryopreservation , Egg Yolk , Insemination, Artificial , Semen Preservation , Semen , Animals , Female , Fertility , Insemination, Artificial/veterinary , Lipoproteins , Male , Pregnancy , Spermatozoa , Swine
20.
Climacteric ; 20(3): 240-247, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28326899

ABSTRACT

OBJECTIVES: The negative publicity about menopausal hormone therapy (MHT) has led to increased use of complementary and alternative medicines (CAM) and non-pharmacological interventions (NPI) for menopausal symptom relief. We report on the prevalence and predictors of CAM/NPI among UK postmenopausal women. METHOD: Postmenopausal women aged 50-74 years were invited to participate in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). A total of 202 638 women were recruited and completed a baseline questionnaire. Of these, 136 020 were sent a postal follow-up-questionnaire between September 2006 and May 2009 which included ever-use of CAM/NPI for menopausal symptom relief. Both questionnaires included MHT use. RESULTS: A total of 88 430 (65.0%) women returned a completed follow-up-questionnaire; 22 206 (25.1%) reported ever-use of one or more CAM/NPI. Highest use was reported for herbal therapies (43.8%; 9725/22 206), vitamins (42.6%; 9458/22 206), lifestyle approaches (32.1%; 7137/22 206) and phytoestrogens (21.6%; 4802/22 206). Older women reported less ever-use of herbal therapies, vitamins and phytoestrogens. Lifestyle approaches, aromatherapy/reflexology/acupuncture and homeopathy were similar across age groups. Higher education, Black ethnicity, MHT or previous oral contraceptive pill use were associated with higher CAM/NPI use. Women assessed as being less hopeful about their future were less likely to use CAM/NPI. CONCLUSION: One in four postmenopausal women reported ever-use of CAM therapies/NPI for menopausal symptom relief, with lower use reported by older women. Higher levels of education and previous MHT use were positive predictors of CAM/NPI use. UKCTOCS Trial registration: ISRCTN22488978.


Subject(s)
Complementary Therapies/statistics & numerical data , Estrogen Replacement Therapy/statistics & numerical data , Hot Flashes/therapy , Menopause/psychology , Ovarian Neoplasms/epidemiology , Aged , Female , Humans , Mass Screening , Middle Aged , Ovarian Neoplasms/prevention & control , Predictive Value of Tests , Prevalence , State Medicine , Surveys and Questionnaires , United Kingdom/epidemiology
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