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1.
PLoS Negl Trop Dis ; 16(4): e0010314, 2022 04.
Article in English | MEDLINE | ID: mdl-35486651

ABSTRACT

BACKGROUND: Dengue (DENV), Ross River (RRV) and Barmah Forest viruses (BFV) are the most common human arboviral infections in Australia and the Pacific Island Countries and Territories (PICTs) and are associated with debilitating symptoms. All are nationally notifiable in Australia, but routine surveillance is limited to a few locations in the PICTs. Understanding the level of human exposure to these viruses can inform disease management and mitigation strategies. To assess the historic and current seroprevalence of DENV, RRV and BFV in Australia and the PICTs we conducted a systematic literature review of all published quantitative serosurveys. METHODOLOGY AND PRINCIPAL FINDINGS: The Preferred Reporting of Items for Systematic Reviews and Meta-Analyses procedures were adopted to produce a protocol to systematically search for published studies reporting the seroprevalence of DENV, RRV and BFV in Australia and the PICTs. Data for author, research year, location, study population, serosurvey methods and positive tests were extracted. A total of 41 papers, reporting 78 serosurveys of DENV, RRV and BFV including 62,327 samples met the inclusion criteria for this review. Seroprevalence varied depending on the assay used, strategy of sample collection and location of the study population. Significant differences were observed in reported seropositivity depending on the sample collection strategy with clinically targeted sampling reporting the highest seroprevalence across all three viruses. Non-stratified seroprevalence showed wide ranges in reported positivity with DENV 0.0% - 95.6%, RRV 0.0% - 100.0%, and BFV 0.3% - 12.5%. We discuss some of the causes of variation including serological methods used, selection bias in sample collection including clinical or environmental associations, and location of study site. We consider the extent to which serosurveys reflect the epidemiology of the viruses and provide broad recommendations regarding the conduct and reporting of arbovirus serosurveys. CONCLUSIONS AND SIGNIFICANCE: Human serosurveys provide important information on the extent of human exposure to arboviruses across: (1) time, (2) place, and (3) person (e.g., age, gender, clinical presentation etc). Interpreting results obtained at these scales has the potential to inform us about transmission cycles, improve diagnostic surveillance, and mitigate future outbreaks. Future research should streamline methods and reduce bias to allow a better understanding of the burden of these diseases and the factors associated with seroprevalence. Greater consideration should be given to the interpretation of seroprevalence in studies, and increased rigour applied in linking seroprevalence to transmission dynamics.


Subject(s)
Alphavirus , Arboviruses , Culicidae , Dengue , Animals , Australia/epidemiology , Chickens , Dengue/epidemiology , Forests , Humans , Seroepidemiologic Studies
2.
Front Immunol ; 13: 842023, 2022.
Article in English | MEDLINE | ID: mdl-35345676

ABSTRACT

The early complement components have emerged as mediators of pro-oncogenic inflammation, classically inferred to cause terminal complement activation, but there are limited data on the activity of terminal complement in cancer. We previously reported elevated serum and tissue C9, the terminal complement component, in esophageal adenocarcinoma (EAC) compared to the precursor condition Barrett's Esophagus (BE) and healthy controls. Here, we investigate the level and cellular fates of the terminal complement complex C5b-9, also known as the membrane attack complex. Punctate C5b-9 staining and diffuse C9 staining was detected in BE and EAC by multiplex immunohistofluorescence without corresponding increase of C9 mRNA transcript. Increased C9 and C5b-9 staining were observed in the sequence normal squamous epithelium, BE, low- and high-grade dysplasia, EAC. C5b-9 positive esophageal cells were morphologically intact, indicative of sublytic or complement-evasion mechanisms. To investigate this at a cellular level, we exposed non-dysplastic BE (BAR-T and CP-A), high-grade dysplastic BE (CP-B and CP-D) and EAC (FLO-1 and OE-33) cell lines to the same sublytic dose of immunopurified human C9 (3 µg/ml) in the presence of C9-depleted human serum. Cellular C5b-9 was visualized by immunofluorescence confocal microscopy. Shed C5b-9 in the form of extracellular vesicles (EV) was measured in collected conditioned medium using recently described microfluidic immunoassay with capture by a mixture of three tetraspanin antibodies (CD9/CD63/CD81) and detection by surface-enhanced Raman scattering (SERS) after EV labelling with C5b-9 or C9 antibody conjugated SERS nanotags. Following C9 exposure, all examined cell lines formed C5b-9, internalized C5b-9, and shed C5b-9+ and C9+ EVs, albeit at varying levels despite receiving the same C9 dose. In conclusion, these results confirm increased esophageal C5b-9 formation during EAC development and demonstrate capability and heterogeneity in C5b-9 formation and shedding in BE and EAC cell lines following sublytic C9 exposure. Future work may explore the molecular mechanisms and pathogenic implications of the shed C5b-9+ EV.


Subject(s)
Adenocarcinoma , Barrett Esophagus , Extracellular Vesicles , Complement Activation , Complement C9/metabolism , Complement Membrane Attack Complex , Complement System Proteins/metabolism , Esophageal Neoplasms , Extracellular Vesicles/metabolism , Humans
3.
Viruses ; 15(1)2022 12 31.
Article in English | MEDLINE | ID: mdl-36680176

ABSTRACT

Old world alphaviruses, such as Ross River virus (RRV), cause debilitating arthralgia during acute and chronic stages of the disease. RRV-induced cartilage degradation has been implicated as a cause of joint pain felt by RRV patients. Chondrocytes are a major cell type of cartilage and are involved in the production and maintenance of the cartilage matrix. It is thought that these cells may play a vital role in RRV disease pathogenesis. In this study, we used RNA-sequencing (RNA-Seq) to examine the transcriptomes of RRV-infected and bystander chondrocytes in the same environment. RRV containing green fluorescent protein (GFP) allowed for the separation of RRV-infected (GFP+) and bystander uninfected cells (GFP-). We found that whereas GFP+ and GFP- populations commonly presented similar gene expression profiles during infection, there were also unique signatures. For example, RIMS2 and FOXJ1 were unique to GFP+ cells, whilst Aim2 and CCL8 were only found in bystander chondrocytes. This indicates that careful selection of potential therapeutic targets is important to minimise adverse effects to the neighbouring uninfected cell populations. Our study serves as a resource to provide more information about the pathways and responses elicited by RRV in cells which are both infected and stimulated because of neighbouring infected cells.


Subject(s)
Alphavirus Infections , Alphavirus , Humans , Chondrocytes/metabolism , Alphavirus/genetics , Ross River virus/genetics , Ross River virus/metabolism
4.
Cancers (Basel) ; 13(12)2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34201241

ABSTRACT

The current endoscopy and biopsy diagnosis of esophageal adenocarcinoma (EAC) and its premalignant condition Barrett's esophagus (BE) is not cost-effective. To enable EAC screening and patient triaging for endoscopy, we developed a microfluidic lectin immunoassay, the EndoScreen Chip, which allows sensitive multiplex serum biomarker measurements. Here, we report the proof-of-concept deployment for the EAC biomarker Jacalin lectin binding complement C9 (JAC-C9), which we previously discovered and validated by mass spectrometry. A monoclonal C9 antibody (m26 3C9) was generated and validated in microplate ELISA, and then deployed for JAC-C9 measurement on EndoScreen Chip. Cohort evaluation (n = 46) confirmed the expected elevation of serum JAC-C9 in EAC, along with elevated total serum C9 level. Next, we asked if the small panel of serum biomarkers improves detection of EAC in this cohort when used in conjunction with patient risk factors (age, body mass index and heartburn history). Using logistic regression modeling, we found that serum C9 and JAC-C9 significantly improved EAC prediction from AUROC of 0.838 to 0.931, with JAC-C9 strongly predictive of EAC (vs. BE OR = 4.6, 95% CI: 1.6-15.6, p = 0.014; vs. Healthy OR = 4.1, 95% CI: 1.2-13.7, p = 0.024). This proof-of-concept study confirms the microfluidic EndoScreen Chip technology and supports the potential utility of blood biomarkers in improving triaging for diagnostic endoscopy. Future work will expand the number of markers on EndoScreen Chip from our list of validated EAC biomarkers.

5.
West J Nurs Res ; 43(4): 298-306, 2021 04.
Article in English | MEDLINE | ID: mdl-32840186

ABSTRACT

Poor self-care is prevalent in patients with heart failure and adversely affects heart failure symptoms, hospitalization, and mortality. Adherence rates to different types of self-care vary in patients with heart failure. The purpose of this study was to examine factors associated with medication adherence, dietary sodium adherence, and symptom management in patients with heart failure. Data were collected using questionnaires, Medication Electronic Monitoring System, and 24-hour urine sodium output (N = 94). In logistic regression analysis, social support, education level, and race were associated with medication adherence (p = .002). Gender, race, perceived control, and depressive symptoms were associated with dietary sodium adherence (p = .030). Gender, education level, and depressive symptoms were associated with symptom management (p = .006). Different factors were associated with each type of self-care. Thus, clinicians need to manage each type of self-care by considering factors associated with it.


Subject(s)
Heart Failure , Self Care , Heart Failure/therapy , Humans , Medication Adherence , Social Support , Surveys and Questionnaires
6.
Parasit Vectors ; 13(1): 484, 2020 Sep 23.
Article in English | MEDLINE | ID: mdl-32967711

ABSTRACT

Changes to Australia's climate and land-use patterns could result in expanded spatial and temporal distributions of endemic mosquito vectors including Aedes and Culex species that transmit medically important arboviruses. Climate and land-use changes greatly influence the suitability of habitats for mosquitoes and their behaviors such as mating, feeding and oviposition. Changes in these behaviors in turn determine future species-specific mosquito diversity, distribution and abundance. In this review, we discuss climate and land-use change factors that influence shifts in mosquito distribution ranges. We also discuss the predictive and epidemiological merits of incorporating these factors into a novel integrated statistical (SSDM) and mechanistic species distribution modelling (MSDM) framework. One potentially significant merit of integrated modelling is an improvement in the future surveillance and control of medically relevant endemic mosquito vectors such as Aedes vigilax and Culex annulirostris, implicated in the transmission of many arboviruses such as Ross River virus and Barmah Forest virus, and exotic mosquito vectors such as Aedes aegypti and Aedes albopictus. We conducted a focused literature search to explore the merits of integrating SSDMs and MSDMs with biotic and environmental variables to better predict the future range of endemic mosquito vectors. We show that an integrated framework utilising both SSDMs and MSDMs can improve future mosquito-vector species distribution projections in Australia. We recommend consideration of climate and environmental change projections in the process of developing land-use plans as this directly impacts mosquito-vector distribution and larvae abundance. We also urge laboratory, field-based researchers and modellers to combine these modelling approaches. Having many different variations of integrated (SDM) modelling frameworks could help to enhance the management of endemic mosquitoes in Australia. Enhanced mosquito management measures could in turn lead to lower arbovirus spread and disease notification rates.


Subject(s)
Biodiversity , Culicidae/physiology , Mosquito Vectors/physiology , Animal Distribution , Animals , Australia , Climate Change , Culicidae/classification , Mosquito Control , Mosquito Vectors/classification
7.
PLoS One ; 14(6): e0217998, 2019.
Article in English | MEDLINE | ID: mdl-31170255

ABSTRACT

Recently the anti-viral effects of prophylactic treatment with the low-molecular-weight heparan sulfate mimetic PG545 in Ross River virus (RRV) infected mice were reported. We further investigated the related, transient pathophysiology of PG545 drug treatment in RRV-infected and mock-infected PG545-treated mice. PG545 treatment resulted in mild lethargy and piloerection, on days after the drug administration. Mice were treated with two or three doses of PG545 within a ten-day period and were subsequently culled at peak disease or at disease resolution. The treatment responses of the spleen and liver were assessed through histology, flow cytometry, gene arrays and serum biochemistry. Microscopy showed an expanded red pulp in the spleen following either two or three treatments with PG545. The red pulp expansion was further demonstrated by the proliferation of megakaryocytes and erythrocyte precursors within the spleen. In addition, flow cytometry and gene array analyses revealed a reduction of lymphocytes within the spleens of PG545-treated mice. Previously unreported, RRV-induced elevations of aspartate aminotransferase (AST) and alanine transaminase (ALT) enzymes and creatinine were also noted in the RRV-infected mice. However, PG545 only reduced AST and ALT levels but not the creatinine levels in infected mice during treatment. Mice treated with three doses of PG545 also showed hepatosplenomegaly and anaemia, which were reversed upon discontinuation of the treatment. In summary, this study demonstrates that dose and frequency related haemopoietic pathophysiology such as hepatosplenomegaly and anaemia, occurred in C57BL/6 mice treated with PG545. However, this effect was reversible once drug administration is terminated.


Subject(s)
Alphavirus Infections/drug therapy , Aspartate Aminotransferases/metabolism , Lymphocytes/drug effects , Lymphocytes/metabolism , Ross River virus/drug effects , Saponins/pharmacology , Alanine Transaminase , Alphavirus Infections/metabolism , Animals , Glucuronidase/metabolism , Liver/drug effects , Liver/metabolism , Mice , Mice, Inbred C57BL , Spleen/drug effects , Spleen/metabolism
8.
Parasit Vectors ; 12(1): 165, 2019 Apr 11.
Article in English | MEDLINE | ID: mdl-30975197

ABSTRACT

Mosquito-borne diseases are associated with major global health burdens. Aedes spp. and Culex spp. are primarily responsible for the transmission of the most medically important mosquito-borne viruses, including dengue virus, West Nile virus and Zika virus. Despite the burden of these pathogens on human populations, the interactions between viruses and their mosquito hosts remain enigmatic. Viruses enter the midgut of a mosquito following the mosquito's ingestion of a viremic blood meal. During infection, virus recognition by the mosquito host triggers their antiviral defense mechanism. Of these host defenses, activation of the RNAi pathway is the main antiviral mechanism, leading to the degradation of viral RNA, thereby inhibiting viral replication and promoting viral clearance. However, whilst antiviral host defense mechanisms limit viral replication, the mosquito immune system is unable to effectively clear the virus. As such, these viruses can establish persistent infection with little or no fitness cost to the mosquito vector, ensuring life-long transmission to humans. Understanding of the mosquito innate immune response enables the discovery of novel antivectorial strategies to block human transmission. This review provides an updated and concise summary of recent studies on mosquito antiviral immune responses, which is a key determinant for successful virus transmission. In addition, we will also discuss the factors that may contribute to persistent infection in mosquito hosts. Finally, we will discuss current mosquito transmission-blocking strategies that utilize genetically modified mosquitoes and Wolbachia-infected mosquitoes for resistance to pathogens.


Subject(s)
Culicidae/immunology , Culicidae/virology , Animals , Humans , Immunity, Innate , Mosquito Control , RNA Interference , RNA, Viral
9.
J Heart Lung Transplant ; 38(9): 920-926, 2019 09.
Article in English | MEDLINE | ID: mdl-30898555

ABSTRACT

BACKGROUND: After 3 years of continuous-flow left ventricular assist device (CF-LVAD) support, nearly a third of patients develop at least moderate aortic insufficiency (AI). Percutaneous occluder devices, surgical aortic valve replacement (SAVR), and urgent heart transplantation are available treatment options. Transcatheter aortic valve replacement (TAVR) has not been widely used for treating symptomatic AI in patients on LVAD support. METHODS: Retrospective chart review and data analysis from October 2010 through August 2017 was performed. A total of 286 patients with end-stage heart failure (ESHF) were implanted with a durable CF-LVAD. Nine patients subsequently developed significant symptomatic AI, which was treated with TAVR. RESULTS: All 9 patients had 1 TAVR procedure with resolution of AI and were discharged home. Procedural complications include valve migration warranting a second valve for stabilization, retroperitoneal and groin hematoma, and pseudoaneurysm requiring thrombin injection. A significant improvement of the New York Heart Association classification was noted from the time of implant to 6 months. Two patients had unplanned heart failure‒related hospitalizations within 6 months. At 6 months, 89% of patients were alive on LVAD support. CONCLUSIONS: TAVR is a successful treatment modality for LVAD patients who develop symptomatic AI.


Subject(s)
Aortic Valve Insufficiency/etiology , Aortic Valve Insufficiency/surgery , Heart-Assist Devices/adverse effects , Transcatheter Aortic Valve Replacement , Adult , Aged , Aortic Valve Insufficiency/diagnosis , Female , Heart Failure/surgery , Humans , Male , Middle Aged , Retrospective Studies , Time Factors , Treatment Outcome
10.
Mol Med Rep ; 16(5): 6170-6177, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28849047

ABSTRACT

Mesenchymal stem cells (MSCs) are often considered to be a good source for the development of regenerative medicine. Previously, we reported that tonsil­derived MSC conditioned medium (T­MSC CM) produces visceral fat reducing effects. As reduced visceral adiposity is closely associated with an increase in circulating adiponectin, the present study investigated the effects of T­MSC CM on adiponectin production. T­MSC CM was collected from previously isolated and characterized T­MSCs and injected into senescence­accelerated mouse prone 6 mice, which exhibit characteristics of aging and obesity. The results demonstrated a reduction in mouse weight and epididymal adipose tissue (eAT) mass following injection of T­MSC CM. Significant increases in adiponectin expression in the eAT, and total and high molecular weight (HMW) adiponectin in the circulation were observed in the T­MSC CM­injected mice compared with control mice using reverse transcription­quantitative polymerase chain reaction, western blot analysis and ELISA. In 3T3­L1 adipocytes, T­MSC CM treatment increased adiponectin secretion and multimerization, as detected using western blotting under non­reducing and non­heat­denaturing conditions. Furthermore, glucose oxidase was used to induce oxidative stress in 3T3­L1 adipocytes and it was observed that T­MSC CM reduced reactive oxygen species production and the expression of certain oxidative stress markers. In addition, the results also demonstrated that the production of HMW adiponectin was increased, which indicates that T­MSC CM may enhance adiponectin multimerization via amelioration of oxidative stress. Further studies are required to elucidate anti­oxidant molecules secreted from T­MSCs, and these results highlight the potential therapeutic relevance of T­MSC CM for the treatment of obesity or obesity­associated diseases.


Subject(s)
Adiponectin/metabolism , Culture Media, Conditioned/metabolism , Mesenchymal Stem Cells/metabolism , Palatine Tonsil/metabolism , Adipocytes/metabolism , Adipose Tissue/metabolism , Animals , Cells, Cultured , Intra-Abdominal Fat/metabolism , Male , Mice , Obesity/metabolism , Oxidative Stress/physiology , Reactive Oxygen Species/metabolism
11.
Biosci Rep ; 37(3)2017 Jun 30.
Article in English | MEDLINE | ID: mdl-28428430

ABSTRACT

Secretion of high molecular weight (HMW) adiponectin is dependent on post-translational modification (PTM) of conserved lysines in the collagenous domain. The present study aims to characterize the enzymes responsible for the PTM of conserved lysines which leads to HMW adiponectin secretion, and to define its significance in relation to obesity. Collagen beta (1-O) galactosyltransferase 1 (GLT25D1) was knocked down in HEK cells modified for the stable expression of adiponectin (adiponectin expressing human embryonic kidney cells, Adipo-HEK) as well as in Simpson Golabi-Behmel-Syndrome (SGBS) adipocytes. Knockdown of GLT25D1 caused a significant decrease in HMW adiponectin in Adipo-HEK cells with no change in total adiponectin. Knockdown in the SGBS cells caused an increase in lipid accumulation yet inhibited adipogenesis. Co-immunoprecipitation with adiponectin and mass spectrometry showed that adiponectin formed a protein complex with lysyl hydroxylase 3 (LH3) and GLT25D1. Transient overexpression of GLT25D1 showed that the intracellular retention of LH3 was dependent on GLT25D1. To determine whether changes in GLT25D1 were significant in obesity, mice were fed a standard chow or high-fat diet (HFD) for 5 weeks. GLT25D1 was significantly decreased in mice fed HFD which coincided with a decrease in HMW adiponectin. We conclude that GLT25D1 regulates HMW adiponectin secretion and lipid accumulation, consistent with changes in mice after high-fat feeding. These results suggest a novel function of GLT25D1 leading to decreased HMW adiponectin secretion in early obesity.


Subject(s)
Adiponectin/metabolism , Galactosyltransferases/metabolism , Adipocytes/metabolism , Animals , Cell Line , Diet, High-Fat/adverse effects , HEK293 Cells , Humans , Lipid Metabolism/physiology , Lipids , Lysine/metabolism , Male , Mice , Mice, Inbred C57BL , Molecular Weight , Obesity/metabolism , Protein Processing, Post-Translational/physiology
12.
FASEB J ; 30(7): 2528-40, 2016 07.
Article in English | MEDLINE | ID: mdl-27006448

ABSTRACT

Adipose tissue expansion occurs through a combination of hypertrophy of existing adipocytes and generation of new adipocytes via the process of hyperplasia, which involves the proliferation and subsequent differentiation of preadipocytes. Deficiencies in hyperplasia contribute to adipose tissue dysfunction and the association of obesity with chronic cardiometabolic diseases. Thus, increased understanding of hyperplastic pathways may be expected to afford novel therapeutic strategies. We have reported that fibroblast growth factor (FGF)-1 promotes proliferation and differentiation of human preadipocytes and recently demonstrated that bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) is a central, proximal effector. Herein, we describe the identification and characterization of carboxypeptidase X (CPX)-1, a secreted collagen-binding glycoprotein, as a novel downstream effector in human primary and Simpson-Golabi-Behmel syndrome preadipocytes. CPX-1 expression increased after treatment of preadipocytes with FGF-1, BAMBI knockdown, or induction of differentiation. CPX-1 knockdown compromised preadipocyte differentiation coincident with reduced collagen expression. Furthermore, preadipocytes differentiated on matrix derived from CPX-1 knockdown cells exhibited reduced Glut4 expression and insulin-stimulated glucose uptake. Finally, CPX-1 expression was increased in adipose tissue from obese mice and humans. Collectively, these findings establish CPX-1 as a positive regulator of adipogenesis situated downstream of FGF-1/BAMBI that may contribute to hyperplastic adipose tissue expansion via affecting extracellular matrix remodeling.-Kim, Y.-H., Barclay, J. L., He, J., Luo, X., O'Neill, H. M., Keshvari, S., Webster, J. A., Ng, C., Hutley, L. J., Prins, J. B., Whitehead, J. P. Identification of carboxypeptidase X (CPX)-1 as a positive regulator of adipogenesis.


Subject(s)
Adipogenesis/physiology , Adipose Tissue/metabolism , Gene Expression Regulation/physiology , Glycoproteins/metabolism , Metalloexopeptidases/metabolism , Adipocytes/metabolism , Adipocytes/physiology , Adipogenesis/drug effects , Adult , Animals , Cell Differentiation , Dietary Fats/administration & dosage , Dietary Fats/adverse effects , Female , Fibroblast Growth Factor 1/genetics , Fibroblast Growth Factor 1/metabolism , Gene Expression Regulation/drug effects , Gene Knockdown Techniques , Glycoproteins/genetics , Humans , Male , Membrane Proteins/genetics , Membrane Proteins/metabolism , Metalloexopeptidases/genetics , Mice , Middle Aged , Obesity/etiology , Obesity/metabolism
13.
Patient Prefer Adherence ; 8: 843-51, 2014.
Article in English | MEDLINE | ID: mdl-24966669

ABSTRACT

BACKGROUND: Poor adherence to disease-modifying drugs is associated with an increased risk of relapse in patients with multiple sclerosis. However, adherence is difficult to assess objectively. RebiSmart(®) (Merck Serono SA, Geneva, Switzerland), a device for subcutaneous (sc) injection of interferon (IFN) ß-1a, features an electronic injection log that can assist in objective monitoring of adherence. OBJECTIVE: To assess adherence to sc IFN ß-1a injections using data from RebiSmart(®). METHODS: This was a single-group, observational, retrospective audit. Adherence data were collected from patients with relapsing multiple sclerosis in the United Kingdom and Ireland who had been prescribed sc IFN ß-1a and had been using RebiSmart(®) for a minimum of 24 months. RESULTS: In total, 225 patients were included in the full analysis set; 72% were in the United Kingdom, and 28% were in Ireland. Overall, the mean age was 44.1 years, and 73% were women. Patients received sc IFN ß-1a 44 µg (68%) or 22 µg (32%) three times per week. Mean adherence over the course of 24 months was 95.0% (median, 99.4%), and similar values were observed across all periods. The proportion of patients with 80% or higher adherence was 92.0% at 12 months and 91.1% at 24 months. CONCLUSION: High adherence to sc IFN ß-1a was observed across all patient groups using RebiSmart(®), according to 2-year treatment adherence data. This may be partly attributed to the expert support patients received, supplemented by routine and regular contact from the MySupport patient-support program, as well as the self-motivation of patients who persisted with treatment for 2 or more years.

14.
Biochem Biophys Res Commun ; 432(1): 28-33, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23376713

ABSTRACT

Adiponectin is a beneficial adipokine with insulin-sensitizing, anti-inflammatory and anti-atherogenic effects. These effects are mediated by two poorly characterised, closely related, atypical seven-transmembrane receptors. In the current report we have used C-terminal, epitope-tagged AdipoR1 and AdipoR2 constructs to monitor cell-surface expression by indirect immunofluorescence microscopy and quantitative plate-based analysis. We demonstrate that only AdipoR1 is constitutively expressed on the cell-surface. Further investigations, involving characterisation of a number of chimeric and truncated constructs, show the non-conserved region of AdipoR2 (residues 1-81) restricts its cell-surface expression. Introduction or deletion of this region, into AdipoR1 or AdipoR2, resulted in inhibition or promotion of cell-surface expression, respectively. We also confirmed that AdipoR1 and AdipoR2 can form heterodimers when co-expressed and that co-expression leads to the cell-surface expression of AdipoR2. Collectively these studies demonstrate that the non-conserved region of AdipoR2 restricts its cell-surface expression and raise the possibility that the majority of cell-surface AdipoR2 may be present in the form of heterodimers.


Subject(s)
Cell Membrane/metabolism , Receptors, Adiponectin/metabolism , Amino Acid Sequence , Animals , CHO Cells , Cricetinae , Humans , Molecular Sequence Data , Protein Multimerization , Protein Structure, Tertiary , Receptors, Adiponectin/genetics , Recombinant Fusion Proteins/metabolism
15.
PLoS One ; 7(12): e51096, 2012.
Article in English | MEDLINE | ID: mdl-23236438

ABSTRACT

We recently reported that Inosine Monophosphate Dehydrogenase (IMPDH), a rate-limiting enzyme in de novo guanine nucleotide biosynthesis, clustered into macrostructures in response to decreased nucleotide levels and that there were differences between the IMPDH isoforms, IMPDH1 and IMPDH2. We hypothesised that the Bateman domains, which are present in both isoforms and serve as energy-sensing/allosteric modules in unrelated proteins, would contribute to isoform-specific differences and that mutations situated in and around this domain in IMPDH1 which give rise to retinitis pigmentosa (RP) would compromise regulation. We employed immuno-electron microscopy to investigate the ultrastructure of IMPDH macrostructures and live-cell imaging to follow clustering of an IMPDH2-GFP chimera in real-time. Using a series of IMPDH1/IMPDH2 chimera we demonstrated that the propensity to cluster was conferred by the N-terminal 244 amino acids, which includes the Bateman domain. A protease protection assay suggested isoform-specific purine nucleotide binding characteristics, with ATP protecting IMPDH1 and AMP protecting IMPDH2, via a mechanism involving conformational changes upon nucleotide binding to the Bateman domain without affecting IMPDH catalytic activity. ATP binding to IMPDH1 was confirmed in a nucleotide binding assay. The RP-causing mutation, R224P, abolished ATP binding and nucleotide protection and this correlated with an altered propensity to cluster. Collectively these data demonstrate that (i) the isoforms are differentially regulated by AMP and ATP by a mechanism involving the Bateman domain, (ii) communication occurs between the Bateman and catalytic domains and (iii) the RP-causing mutations compromise such regulation. These findings support the idea that the IMPDH isoforms are subject to distinct regulation and that regulatory defects contribute to human disease.


Subject(s)
IMP Dehydrogenase/metabolism , Protein Isoforms/metabolism , Purine Nucleotides/metabolism , Animals , CHO Cells , Cricetinae , HeLa Cells , Humans , IMP Dehydrogenase/genetics , Mutation , Protein Isoforms/genetics , Purine Nucleotides/genetics
16.
Diabetes ; 61(9): 2320-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22923652

ABSTRACT

Obesity, type 2 diabetes, and cardiovascular disease correlate with infiltration to adipose tissue of different immune cells, with uncertain influences on metabolism. Rats were fed a diet high in carbohydrates and saturated fats to develop diet-induced obesity over 16 weeks. This nutritional overload caused overexpression and secretion of phospholipase A(2) group IIA (pla2g2a) from immune cells in adipose tissue rather than adipocytes, whereas expression of adipose-specific phospholipase A(2) (pla2g16) was unchanged. These immune cells produce prostaglandin E(2) (PGE(2)), which influences adipocyte signaling. We found that a selective inhibitor of human pla2g2a (5-(4-benzyloxyphenyl)-(4S)-(phenyl-heptanoylamino)-pentanoic acid [KH064]) attenuated secretion of PGE(2) from human immune cells stimulated with the fatty acid, palmitic acid, or with lipopolysaccharide. Oral administration of KH064 (5 mg/kg/day) to rats fed the high-carbohydrate, high-fat diet prevented the overexpression of pla2g2a and the increased macrophage infiltration and elevated PGE(2) concentrations in adipose tissue. The treatment also attenuated visceral adiposity and reversed most characteristics of metabolic syndrome, producing marked improvements in insulin sensitivity, glucose intolerance, and cardiovascular abnormalities. We suggest that pla2g2a may have a causal relationship with chronic adiposity and metabolic syndrome and that its inhibition in vivo may be a valuable new approach to treat obesity, type 2 diabetes, and metabolic dysfunction in humans.


Subject(s)
Adipocytes/drug effects , Adipose Tissue/physiology , Group II Phospholipases A2/antagonists & inhibitors , Metabolic Syndrome/prevention & control , Pentanoic Acids/pharmacology , Adipocytes/physiology , Animals , Cell Line , Diet, High-Fat , Dinoprostone/metabolism , Glucose Intolerance/prevention & control , Humans , Insulin Resistance , Lipolysis/drug effects , Macrophages/physiology , Male , Mast Cells/physiology , Mice , Monocytes/physiology , Obesity/physiopathology , Phospholipases A2, Calcium-Independent/biosynthesis , Rats , Rats, Wistar , Signal Transduction/drug effects , T-Lymphocytes/physiology , Tumor Suppressor Proteins/biosynthesis
17.
Diabetes ; 61(1): 124-36, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22187378

ABSTRACT

Adipose tissue dysfunction underpins the association of obesity with type 2 diabetes. Adipogenesis is required for the maintenance of adipose tissue function. It involves the commitment and subsequent differentiation of preadipocytes and is coordinated by autocrine, paracrine, and endocrine factors. We previously reported that fibroblast growth factor-1 (FGF-1) primes primary human preadipocytes and Simpson Golabi Behmel syndrome (SGBS) preadipocytes and increases adipogenesis through a cascade involving extracellular signal-related kinase 1/2 (ERK1/2). Here, we aimed to use the FGF-1 system to identify novel adipogenic regulators. Expression profiling revealed bone morphogenetic protein (BMP) and activin membrane-bound inhibitor (BAMBI) as a putative FGF-1 effector. BAMBI is a transmembrane protein and modulator of paracrine factors that regulate adipogenesis, including transforming growth factor (TGF) superfamily members (TGF-ß and BMP) and Wnt. Functional investigations established BAMBI as a negative regulator of adipogenesis and modulator of the anti- and proadipogenic effects of Wnt3a, TGF-ß1, and BMP-4. Further studies showed that BAMBI expression levels are decreased in a mouse model of diet-induced obesity. Collectively, these findings establish BAMBI as a novel, negative regulator of adipogenesis that can act as a nexus to integrate multiple paracrine signals to coordinate adipogenesis. Alterations in BAMBI may play a role in the (patho)physiology of obesity, and manipulation of BAMBI may present a novel therapeutic approach to improve adipose tissue function.


Subject(s)
Adipogenesis/genetics , Adipokines/genetics , Autocrine Communication/genetics , Membrane Proteins/physiology , Paracrine Communication/genetics , Adipogenesis/drug effects , Adipokines/metabolism , Animals , Autocrine Communication/drug effects , Cells, Cultured , Down-Regulation/drug effects , Down-Regulation/genetics , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Gene Knockdown Techniques , Humans , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/genetics , Membrane Proteins/isolation & purification , Mice , Mice, Inbred C57BL , Mice, Obese , Obesity/genetics , Obesity/metabolism , Paracrine Communication/drug effects , RNA, Small Interfering/pharmacology
18.
Community Pract ; 84(1): 35-7, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21370692

ABSTRACT

This case history describes the first application of the Attachment and Bio-behavioural Catch-up (ABC) programme in the UK. It illustrates the key role and value of primary care clinicians in early infancy. The health visitor's careful and reflective observations, and her close links with a GP who shared her understanding of why these were significant, were the only means for this family to access help. The need for interventions in attachment is only likely to be identified by health visitors, with their unique opportunities to see families in their own homes.


Subject(s)
Community Health Nursing/organization & administration , Depression, Postpartum/diagnosis , Depression, Postpartum/prevention & control , Health Promotion/organization & administration , Mother-Child Relations , Nursing Assessment/organization & administration , Depression, Postpartum/psychology , Early Diagnosis , Female , General Practice/organization & administration , Humans , Infant, Newborn , Male , Maternal Behavior , Object Attachment , Postnatal Care/organization & administration , Primary Health Care/organization & administration
19.
Eur J Cardiovasc Prev Rehabil ; 17(4): 393-402, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20498608

ABSTRACT

BACKGROUND: Heart failure is a common and costly condition, particularly in the elderly. A range of models of interventions have shown the capacity to decrease hospitalizations and improve health-related outcomes. Potentially, cardiac rehabilitation models can also improve outcomes. AIM: To assess the impact of a nurse-coordinated multidisciplinary, cardiac rehabilitation program to decrease hospitalizations, increase functional capacity, and meet the needs of patients with heart failure. METHOD: In a randomized control trial, a total of 105 patients were recruited to the study. Patients in the intervention group received an individualized, multidisciplinary 12-week cardiac rehabilitation program, including an individualized exercise component tailored to functional ability and social circumstances. The control group received an information session provided by the cardiac rehabilitation coordinator and then follow-up care by either their cardiologist or general practitioner. This trial was stopped prematurely after the release of state-based guidelines and funding for heart failure programs. RESULTS: During the study period, patients in the intervention group were less likely to have been admitted to hospital for any cause (44 vs. 69%, P = 0.01) or after a major acute coronary event (24 vs. 55%, P = 0.001). Participants in the intervention group were more likely to be alive at 12 months, (93 vs. 79%; P = 0.03) (odds ratio = 3.85; 95% confidence interval=1.03-14.42; P = 0.0042). Quality of life scores improved at 3 months compared with baseline (intervention t = o/-4.37, P<0.0001; control t = /-3.52, P<0.01). Improvement was also seen in 6-min walk times at 3 months compared with baseline in the intervention group (t = 3.40; P = 0.01). CONCLUSION: This study shows that a multidisciplinary heart failure cardiac rehabilitation program, including an individualized exercise component, coordinated by a specialist heart failure nurse can substantially reduce both all-cause and cardiovascular readmission rates, improve functional status at 3 months and exercise tolerance.


Subject(s)
Exercise Therapy , Heart Failure/rehabilitation , Hospitalization , Outpatient Clinics, Hospital , Patient Readmission , Aged , Chi-Square Distribution , Counseling , Exercise Tolerance , Female , Heart Failure/mortality , Heart Failure/nursing , Heart Failure/physiopathology , Humans , Kaplan-Meier Estimate , Logistic Models , Male , Middle Aged , New South Wales , Odds Ratio , Patient Care Team , Quality of Life , Recovery of Function , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
20.
Biochem Biophys Res Commun ; 392(2): 234-9, 2010 Feb 05.
Article in English | MEDLINE | ID: mdl-20074551

ABSTRACT

The pleiotropic effects of the insulin-sensitizing adipokine adiponectin are mediated, at least in part, by two seven-transmembrane domain receptors AdipoR1 and AdipoR2. Recent reports indicate a role for AdipoR-binding proteins, namely APPL1, RACK1 and CK2beta, in proximal signal transduction events. Here we demonstrate that endoplasmic reticulum protein 46 (ERp46) interacts specifically with AdipoR1 and provide evidence that ERp46 modulates adiponectin signalling. Co-immunoprecipitation followed by mass spectrometry identified ERp46 as an AdipoR1-, but not AdipoR2-, interacting protein. Analysis of truncated constructs and GST-fusion proteins revealed the interaction was mediated by the cytoplasmic, N-terminal residues (1-70) of AdipoR1. Indirect immunofluorescence microscopy and subcellular fractionation studies demonstrated that ERp46 was present in the ER and the plasma membrane (PM). Transient knockdown of ERp46 increased the levels of AdipoR1, and AdipoR2, at the PM and this correlated with increased adiponectin-stimulated phosphorylation of AMPK. In contrast, adiponectin-stimulated phosphorylation of p38MAPK was reduced following ERp46 knockdown. Collectively these results establish ERp46 as the first AdipoR1-specific interacting protein and suggest a role for ERp46 in adiponectin receptor biology and adiponectin signalling.


Subject(s)
Adiponectin/metabolism , Protein Disulfide-Isomerases/metabolism , Receptors, Adiponectin/metabolism , Cell Membrane/metabolism , Endoplasmic Reticulum/metabolism , HeLa Cells , Humans , Immunoprecipitation , Protein Disulfide-Isomerases/genetics , Protein Interaction Mapping , Signal Transduction
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