RESUMO
Global pandemics are likely to increase in frequency and severity, and media communication of key messages represents an important mediator of the behavior of individuals in response to public health countermeasures. Where the media places responsibility during a pandemic is therefore important to study as blame is commonly used as a tool to influence public behavior but can also lead to the subjective persecution of groups. The aim of this paper is to investigate where the media places responsibility for COVID-19 in Australia. Specifically, we identify the key themes and frames that are present and observe how they changed over the course of the COVID-19 pandemic in relation to government actions and progression of the pandemic. Understanding media representations of the COVID-19 pandemic will provide insights into ways in which responsibility is framed in relation to health action. Newspaper articles from the Australian and the Sydney Morning Herald were sampled between January 20 and March 31 2020 on every second Monday. Factiva was used to identify and download newspaper articles using the following search criteria: "COVID-19" OR coronavirus OR "Wuhan virus" OR "corona virus" OR "Hebei virus" OR "wet market" OR (Wuhan AND virus) OR (market AND Wuhan and virus) or (China AND Virus) or (Novel AND Virus). Articles were imported into Nvivo and thematic and framing analyses were used. The results show that framing of the pandemic was largely based on societal issues with the theme of economic disruption prevalent throughout the study time period. Moral evaluations of the pandemic were infrequent initially but increased co-incident with the first signs of "flattening of the curve." Explicit examples of blame were very rare but were commonly implied based on the causal origin of the virus. The Australian printed media were slow to report on the COVID-19 pandemic, in addition they were reluctant to apportion blame until the end of the study period, after confirmed case rates had begun to slow. This is interpreted as being due to an evaluation of the pandemic risks as low by the media and therefore the tools of othering and blame were not used until after the study period when the actual risks had begun to abate, more consistent with an inquiry than a mediating mechanism.
Assuntos
COVID-19 , Pandemias , Austrália/epidemiologia , China , Humanos , Pandemias/prevenção & controle , SARS-CoV-2RESUMO
Cardiovascular disease and cancer are increased in Type 2 diabetes. TPM1 and TPM4 genes encode proteins associated with cardiovascular and neoplastic disease. High (HMW) and low (LMW) molecular weight isoforms from TPM1 and TPM4 are altered in several cancer cells and the 3'UTR of TPM1 mRNA is tumour suppressive. Leukocytes influence cardiovascular and neoplastic disease by immunosurveillance for cancer and by chronic inflammation in Type 2 diabetes and cardiovascular disease. The aim was to determine changes in expression of isoforms from TPM1 and TPM4 genes in leukocytes from Type 2 diabetic patients and to use the leukocyte cell line THP1 to identify possible mediators of changes in the patients. Gene expression was determined by RT-qPCR. In diabetes, expression of HMW isoforms from TPM1 were markedly decreased (0.55 v 1.00; p = 0.019) but HMW isoforms from TPM4 were not significantly different (0.76 v 1.00; p = 0.205). Within individual variance in expression of HMW isoforms was very high. The change in expression in HMW isoforms from TPM1 and TPM4 was replicated in THP1 cells treated with 1 ng/ml TNFα (0.10 and 0.12 v 1.00 respectively) or 10 ng/ml IL-1α (0.17 and 0.14 v 1.00 respectively). Increased insulin or glucose concentrations had no substantial effects on TPM1 or TPM4 expression. Decreased TPM1 mRNA resulted in decreases in HMW protein levels. Expression of HMW isoforms from TPM1 is decreased in Type 2 diabetes. This is probably due to increased levels of inflammatory cytokines TNFα and IL-1α in Type 2 diabetes. Lower levels of TPM1 mRNA reduce tumour suppression and could contribute to increased cancer risk in Type 2 diabetes. Decreased HMW tropomyosin isoforms are associated with cancer. Decreased HMW isoforms give rise to cells that are more plastic, motile, invasive and prone to dedifferentiation resulting in leukocytes that are more invasive but less functionally effective.
Assuntos
Adipocinas/farmacologia , Diabetes Mellitus Tipo 2/genética , Expressão Gênica/efeitos dos fármacos , Tropomiosina/genética , Western Blotting , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Glucose/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Mediadores da Inflamação/farmacologia , Insulina/farmacologia , Interleucina-1alfa/farmacologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Peso Molecular , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tropomiosina/química , Tropomiosina/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Williams Syndrome Transcription Factor (WSTF) is one of â¼25 haplodeficient genes in patients with the complex developmental disorder Williams Syndrome (WS). WS results in visual/spatial processing defects, cognitive impairment, unique behavioral phenotypes, characteristic "elfin" facial features, low muscle tone and heart defects. WSTF exists in several chromatin remodeling complexes and has roles in transcription, replication, and repair. Chromatin remodeling is essential during embryogenesis, but WSTF's role in vertebrate development is poorly characterized. To investigate the developmental role of WSTF, we knocked down WSTF in Xenopus laevis embryos using a morpholino that targets WSTF mRNA. BMP4 shows markedly increased and spatially aberrant expression in WSTF-deficient embryos, while SHH, MRF4, PAX2, EPHA4 and SOX2 expression are severely reduced, coupled with defects in a number of developing embryonic structures and organs. WSTF-deficient embryos display defects in anterior neural development. Induction of the neural crest, measured by expression of the neural crest-specific genes SNAIL and SLUG, is unaffected by WSTF depletion. However, at subsequent stages WSTF knockdown results in a severe defect in neural crest migration and/or maintenance. Consistent with a maintenance defect, WSTF knockdowns display a specific pattern of increased apoptosis at the tailbud stage in regions corresponding to the path of cranial neural crest migration. Our work is the first to describe a role for WSTF in proper neural crest function, and suggests that neural crest defects resulting from WSTF haploinsufficiency may be a major contributor to the pathoembryology of WS.
Assuntos
Crista Neural/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Animais , Apoptose/genética , Sequência de Bases , Padronização Corporal/genética , Movimento Celular/genética , Desenvolvimento Embrionário/genética , Feminino , Técnicas de Silenciamento de Genes/métodos , Humanos , Dados de Sequência Molecular , Crista Neural/crescimento & desenvolvimento , Crista Neural/metabolismo , Síndrome de Williams/genética , Síndrome de Williams/metabolismoRESUMO
High and low molecular weight (LMW) tropomyosin isoforms, by regulation of actin filaments, have a major role in the regulation of cell behaviour. They affect malignant transformation, motility, differentiation, metastasis and cell membrane protein presentation. Expression of LMW isoforms from the TPM1 and TPM3 genes have an important role in these effects but the regulation of their expression is unknown. Luciferase assays on a progressively truncated 1.7 kb fragment upstream of the exon 1b translation start site in the TPM1 and TPM3 genes in HEK-293 cells showed upstream activation sequences in TPM1 between -152 and -139 bp and in TPM3 between -154 and -102 bp. The effect of mutating candidate transcription factor binding sites identified an AML1-like transcription factor binding site in TPM1 and a cAMP response element in TPM3. Downstream from the primary activation sequence in TPM1 was a repressor region corresponding to two Sp/KLF family binding GC boxes. Band shift assays confirmed that deletion of these sites altered transcription factor binding and ChIP assays confirmed the presence of AML1 and CREB at the TPM1 and TPM3 activation sequences in the respective promoters. Expression of LMW isoforms from TPM1 and TPM3 genes is regulated very differently. This facilitates regulation of the many cell processes involving these proteins. In situations where these proteins have a critical role, such as cancer metastasis, it also facilitates specific intervention.
Assuntos
Regiões 3' não Traduzidas , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Tropomiosina/genética , Animais , Sítios de Ligação , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , AMP Cíclico/metabolismo , Genes Reporter , Células HEK293 , Humanos , Luciferases , Dados de Sequência Molecular , Peso Molecular , Mutação , Ligação Proteica , Alinhamento de Sequência , Transdução de Sinais/genética , Tropomiosina/química , Tropomiosina/metabolismoRESUMO
BACKGROUND: Inflammation contributes to the development of atherosclerotic lesions in the metabolic syndrome. Tropomyosin isoform expression is altered in this disease and has a role in inflammatory cell plasticity, motility, and insulin sensitivity. We determined the frequency of haplotype carriage of three single-nucleotide polymorphisms (SNPs) in the short isoform promoter of the TPM1 gene in 300 normal controls and 500 metabolic syndrome patients. The effect of each haplotype on tropomyosin gene expression was assessed. METHODS: PCR-restriction fragment length polymorphism assays were developed for each polymorphism. Promoter activity was measured using luciferase assays in the insulin-sensitive human embryonic kidney (HEK) 293 and the monocyte THP-1 lines. RESULTS: The SNPs -111(T/C), -426(T/C), and -491(A/G), relative to the TPM1 short isoform transcription start site, occurred in haplotypes ATT, GCT, GTT, and GTC, and were in strong linkage disequilibrium. ATT had a frequency of 66%. The presence of -491G, which conforms to a predicted binding site for transcription factor AML-1, caused a decrease in gene expression of 24% in the HEK 293 cells. In the THP-1 cells, haplotypes GTC and GTT gave 24% lower expression, whereas haplotype GCT gave expression at wild-type levels. The carriage of a -491G allele gave an odds ratio of 1.4 (95% CI 1.02-1.8) for the metabolic syndrome (P < 0.03). CONCLUSIONS: A polymorphism in the TPM1 short isoform promoter region is predicted to alter transcription factor binding, alters gene expression and is associated with the metabolic syndrome. This could affect inflammatory cells and cytoskeleton-mediated insulin signaling.
Assuntos
Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único , Tropomiosina/genética , Idoso , Idoso de 80 Anos ou mais , Expressão Gênica , Frequência do Gene , Humanos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Fatores de RiscoRESUMO
There is substantial evidence to suggest that complement activation plays a pivotal role in the pathogenesis of IgA nephropathy. Mesangial C3 deposition is seen in approximately 90% of patients and polymeric IgA has been shown to activate the alternative and lectin pathways. In addition there have been reports of deficiency and mutations in the serum complement regulator factor H (CFH) in association with IgA nephropathy. In this study we have examined the hypothesis that CFH is a susceptibility factor for IgA nephropathy. In 46 IgA nephropathy patients we undertook genotyping of three CFH SNPS (rs3753394, rs3753396 and rs1065489). There was no significant difference in the allele frequency of these 3 SNPs between the patients and normal controls. In the same group of patients we undertook mutation screening of CFH exons 18-23 using direct sequencing and found no abnormalities. All the patients had a normal serum factor H concentration. In this small cohort of IgA nephropathy patients we have not found evidence to support the hypothesis that factor H is a major susceptibility factor for the disease.
Assuntos
Predisposição Genética para Doença , Glomerulonefrite por IGA/genética , Adolescente , Adulto , Idoso , Biópsia , Estudos de Coortes , Complemento C3/análise , Complemento C4/análise , Fator H do Complemento/análise , Fator H do Complemento/genética , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genótipo , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/fisiologia , Adulto JovemRESUMO
A polymorphism of the alpha-subunit of adducin, Gly460-->Trp, may affect membrane ion transport and be associated with human EH (essential hypertension). The alpha-adducin Gly460-->Trp polymorphism was determined in 242 NC (normal controls) and 73 patients with EH and was related to the membrane ion transport marker in EH, erythrocyte Na/LiCT (sodium-lithium countertransport), in a subgroup of these subjects. The Km for external sodium was lower in patients with EH than NC. The Km of the Trp allele was lower than with the Gly/Gly genotype [NC, 105+/-6 compared with 88+/-5 mmol Na/l respectively (P=0.05); patients with EH, 76+/-5 compared with 64+/-4 mmol Na/l respectively (P=0.06)]. The Km was lower in patients with EH than NC for any adducin genotype. Thiol alkylation with NEM (N-ethylmaleimide) caused a decrease in Km in NC, but not in patients with EH. With a Trp allele, NEM lowered Km less in NC (-20 compared with -35) and increased it in patients with EH (+24 compared with +3; P=0.007 for genotype effect). Thiol alkylation with NEM caused an increase in Vmax in patients with EH but not in NC. With a Trp allele, NEM increased Vmax substantially in patients with EH (+0.12 compared with +0.03) but did not cause a decrease in NC (+0.02 compared with -0.06; P=0.007 for genotype effect). In conclusion, the Gly460-->Trp polymorphism of alpha-adducin modifies the kinetics of Na/LiCT. The effect of this genotype is different in patients with EH compared with NC and it does not explain the abnormal kinetics in patients with EH. The Trp allele was not associated with disease in the population studied. Several cytoskeletal proteins may interact with adducin in the overall phenotype of EH.
Assuntos
Antiporters/metabolismo , Proteínas de Ligação a Calmodulina/genética , Eritrócitos/metabolismo , Hipertensão/genética , Adulto , Análise de Variância , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Citoesqueleto/metabolismo , Membrana Eritrocítica/metabolismo , Etilmaleimida/metabolismo , Feminino , Genótipo , Humanos , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo GenéticoRESUMO
Abnormal erythrocyte sodium-lithium countertransport is common in a subgroup of patients with essential hypertension and a strong family history of hypertension and cardiovascular disease. We have previously shown that the abnormality in sodium-lithium countertransport is associated with tropomyosin, a cytoskeletal protein required to stabilize actin filament formation. Leukocyte trafficking events, which depend on cytoskeletal reorganization, are also altered in patients with essential hypertension with abnormal sodium-lithium countertransport. The aim of this study was to determine whether there is an abnormality in isoforms of tropomyosin that are common to erythrocytes and leukocytes. Analysis of reticulocyte RNA by reverse transcription (RT) and polymerase chain reaction (PCR) showed expression of TPMN and TPM5b isoforms of tropomyosin. No other isoforms were expressed. These isoforms were also detected in RNA from leukocytes. In patients with essential hypertension with abnormal erythrocyte sodium-lithium countertransport compared with normal control subjects, there was a higher TPMN/TPM5b ratio of protein in erythrocytes (median 3.8 [range 1.8 to 6.6] versus 2.9 [1.9 to 4.0], P<0.001) and of RNA in leukocytes (3.7 [1.7 to 8.2] versus 2.6 [1.2 to 4.3], P<0.01). Furthermore, the protein ratio of TPMN/TPM5b in erythrocytes showed significant correlation with the V(max)/K(m) ratio of sodium-lithium countertransport across the patient groups (r=-0.42; P<0.01). Therefore, altered tropomyosin expression may be the underlying abnormality associated with blood cell membrane changes in essential hypertension and implicates the cytoskeleton in the pathogenesis of the disease in a major subgroup of patients.
Assuntos
Hipertensão/genética , Tropomiosina/genética , Idoso , Animais , Antiporters/metabolismo , Northern Blotting , Western Blotting , Eritrócitos/metabolismo , Feminino , Expressão Gênica , Humanos , Hipertensão/metabolismo , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reticulócitos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tropomiosina/metabolismoRESUMO
Microalbuminuria in Type I diabetes involves a cell membrane abnormality and is associated with a large increase in cardiovascular risk. The hypothesis that the membrane abnormality alters granule exocytosis in neutrophils, which could contribute to the increased incidence of cardiovascular disease, was investigated. PMA-stimulated expression of CD11b and CD69 on neutrophils from normal controls (NC), long-term uncomplicated Type I diabetic control patients (DC) and diabetic nephropathy patients (DN) was determined by fluorescence activated cell scanning. Neutrophils from DN were faster than neutrophils from either NC or DC to exocytose primary granules with CD69 following initial expression of the adhesion molecule CD11b. However, a larger proportion of neutrophils from DN failed to withdraw CD11b from the cell membrane after 90 min incubation. The protein kinase C (PKC) inhibitor, bisindolylmaleimide (BIM), showed that a larger proportion of neutrophils from DN, compared with DC or NC, exocytosed primary granules independent of PKC. The calpain inhibitor, E64d, showed that a larger proportion of neutrophils from both groups of diabetic patients, compared with NC, exocytosed primary granules independent of calpain. Cytoskeletal disruption with cytochalasin D had an effect on CD11b and CD69 exocytosis similar to that of BIM and E64d. The pathways controlling granule exocytosis in neutrophils from diabetic patients are abnormal. A change characteristic of DN causes rapid exocytosis of primary granules, and also causes the adhesion molecule CD11b to persist on an increased proportion of neutrophils. This will make an important contribution to increased vascular damage in these patients.