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H7N7 Avian Influenza Virus Mutation from Low to High Pathogenicity on a Layer Chicken Farm in the UK
Alexander M. P. Byrne Scott M. Reid Amanda H. Seekings Alejandro Núez Ana B. Obeso Prieto Susan Ridout Caroline J. Warren Anita Puranik Vanessa Ceeraz Stephen Essen Marek J. Slomka Jill Banks Ian H. Brown Sharon M. Brookes 《Viruses》2021,13(2)
Avian influenza virus (AIV) subtypes H5 and H7 are capable of mutating from low to high pathogenicity strains, causing high mortality in poultry with significant economic losses globally. During 2015, two outbreaks of H7N7 low pathogenicity AIV (LPAIV) in Germany, and one each in the United Kingdom (UK) and The Netherlands occurred, as well as single outbreaks of H7N7 high pathogenicity AIV (HPAIV) in Germany and the UK. Both HPAIV outbreaks were linked to precursor H7N7 LPAIV outbreaks on the same or adjacent premises. Herein, we describe the clinical, epidemiological, and virological investigations for the H7N7 UK HPAIV outbreak on a farm with layer chickens in mixed free-range and caged units. H7N7 HPAIV was identified and isolated from clinical samples, as well as H7N7 LPAIV, which could not be isolated. Using serological and molecular evidence, we postulate how the viruses spread throughout the premises, indicating potential points of incursion and possible locations for the mutation event. Serological and mortality data suggested that the LPAIV infection preceded the HPAIV infection and afforded some clinical protection against the HPAIV. These results document the identification of a LPAIV to HPAIV mutation in nature, providing insights into factors that drive its manifestation during outbreaks. 相似文献
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Quality of life (QOL) measurement may aid decision making in the treatment of patients with oesophageal cancer but must be clinically valid to be useful. This study considered if the European Organisation for Research and Treatment of Cancer QOL questionnaire, the QLQ-C30, showed differing results in two clinically distinct groups of patients with oesophageal cancer and also investigated the correlation between dysphagia grade and various scales of QOL. Patients treated by oesophagectomy reported significantly better physical, emotional, cognitive, and global health scores than those in the palliative treatment group. Patients who received palliative treatment had significantly worse pain, fatigue, appetite loss, constipation, and dysphagia. The correlations between dysphagia grade and each of the QOL scales and items in both groups of patients were poor. This questionnaire differentiates clearly between the two clinically distinct groups of patients, but to be an entirely appropriate indicator of QOL in patients with oesophageal cancer, an additional specific oesophageal module including a dysphagia scale is required. 相似文献
65.
Carl W. Kotze James H.F. Rudd Balaji Ganeshan Leon J. Menezes Jocelyn Brookes Obiekezie Agu Syed W. Yusuf Ashley M. Groves 《Atherosclerosis》2014
Objective
There is a need for prognostic biomarkers for risk assessment of small abdominal aortic aneurysm (AAA). Since CT textural analysis of tissue is a recognized feature of adverse biology and patient outcome in other diseases, we investigated it as a possible biomarker in small AAA.Methods
Fifty consecutive patients (46-men, 4-woman, median-age 75y, range 56–85) with small AAA (3–5.5 cm) under surveillance undergoing serial ultrasound were prospectively recruited and assessed at baseline with CT texture analysis (CTTA) and 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG-PET). We followed forty patients (36-men, 4-woman, median-age = 74 y, range 60–85, participation rate = 80% for 1 year. For each axial image, CTTA using the filtration-histogram technique was carried out using a software algorithm that selectively extracts texture features of different coarseness (fine, medium and coarse) and intensity variation. Standard-deviation (SD) and kurtosis (K) at each feature-scale were measured. The maximum standardized uptake value (SUVmax) of 18F-FDG in each axial image of the AAA was also measured with corrections for blood pool 18F-FDG activity to assess AAA metabolic activity. Specificity, sensitivity, and c-statistics were calculated with 95% confidence intervals for prediction of significant AAA expansion (≥2 mm) by CTTA measures before and after adjusting for clinical variables.Results
The median aneurysm expansion at 12 months was 2.0 mm, (IQR 0.0–4.0). Coarse texture SD correlated inversely with AAA SUVmax (rs = −0.456, P = 0.003). Medium coarse texture K correlated significantly with future AAA expansion adjusted for baseline size (rs = 0.343, P = 0.030). AAA SUVmax correlated inversely with AAA expansion corrected for baseline size (rs = −0.383, P = 0.015). Medium texture K was a strong predictor of significant AAA expansion (area under the Receiver-operating-characteristic (ROC) curve was 0.813) after adjusting for clinical variables.Conclusion
We have shown evidence that CT signal heterogeneity measurements in small aortic aneurysm may be considered as a risk stratification tool in future prospective studies to identify aneurysms at risk of significant expansion. CT textural data appears to reflect AAA metabolism measured by PET. 相似文献66.
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68.
Sergiy M. Nadtochiy Lindsay S. Burwell Christopher A. Ingraham Cody M. Spencer Alan E. Friedman Carl A. Pinkert Paul S. Brookes 《Journal of molecular and cellular cardiology》2009,46(6):960-968
The reversible S-nitrosation and inhibition of mitochondrial complex I is a potential mechanism of cardioprotection, recruited by ischemic preconditioning (IPC), S-nitrosothiols, and nitrite. Previously, to exploit this mechanism, the mitochondrial S-nitrosating agent S-nitroso-2-mercaptopropionyl glycine (SNO-MPG) was developed, and protected perfused hearts and isolated cardiomyocytes against ischemia–reperfusion (IR) injury. In the present study, the murine left anterior descending coronary artery (LAD) occlusion model of IR injury was employed, to determine the protective efficacy of SNO-MPG in vivo. Intraperitoneal administration of 1 mg/kg SNO-MPG, 30 min prior to occlusion, significantly reduced myocardial infarction and improved EKG parameters, following 30 min occlusion plus 2 or 24 h reperfusion. SNO-MPG protected to the same degree as IPC, and notably was also protective when administered at reperfusion. Cardioprotection was accompanied by increased mitochondrial protein S-nitrosothiol content, and inhibition of complex I, both of which were reversed after 2 h reperfusion. Finally, hearts from mice harboring a heterozygous mutation in the complex I NDUSF4 subunit were refractory to protection by either SNO-MPG or IPC, suggesting that a fully functional complex I, capable of reversible inhibition is critical for cardioprotection. Overall, these results are consistent with a role for mitochondrial S-nitrosation and complex I inhibition in the cardioprotective mechanism of IPC and SNO-MPG in vivo. 相似文献
69.
David RH Christie Kenneth W Tiver 《Journal of Medical Imaging and Radiation Oncology》1996,40(3):331-333
Five patients who received radiotherapy (RT) for 7 melanotic freckles (MF, also known as Hutchinson's freckles, lentigo maligna) were reviewed 8 to 37 months after their treatment by RT. Local control and a favourable cosmetic result occurred in all patients. Treatment toxicity was minimal. Few reports about the use of RT for MF exist. Many other treatments including observation alone have been associated with high rates of recurrence, and in some cases conversion to invasive melanoma has occurred. RT appears to be a safe and effective treatment for this condition, providing that doses equivalent to 44 Gy in 11 fractions or more are given. 相似文献
70.
Malcolm RL Ludwick L Brookes DL Hanna JN 《Australian and New Zealand journal of public health》2000,24(4):353-355
BACKGROUND: In early 1999, five teenagers from the same Indigenous community were notified as having hepatitis B. Hepatitis B vaccine should have been offered to this cohort of teenagers in a 'catch-up' program during the late 1980s when they were of pre-school age. OBJECTIVES: To determine the vaccination status of residents of the community born between 1981 and 1985 (inclusive) and to ascertain the prevalence of markers of hepatitis B infection and carriage in the incompletely vaccinated teenagers in this cohort. METHODS: Community health records were examined to identify all residents in the study cohort. Immunisation records were obtained from local hospital records and from a statewide computerised vaccination database. Serological tests for markers of hepatitis B infection and carriage were performed on blood samples from the incompletely vaccinated teenagers. RESULTS: Only 44% of 235 teenagers who had their vaccination status assessed were fully vaccinated. One hundred and eleven (47%) of the cohort had not received any hepatitis B vaccine. Over 90% of the incompletely vaccinated had been infected with the hepatitis B virus and 26% of these were hepatitis B carriers. CONCLUSIONS: Despite the availability of an effective hepatitis B vaccine and the recommendation for a catch-up program, the pre-school aged cohort of children at the community were not effectively targeted for vaccination. Hepatitis B remains a consequential infection in Indigenous communities in North Queensland. IMPLICATIONS: Initiatives to control hepatitis B need to be enhanced within existing maternal and child health, sexual health, alcohol and drug and chronic disease management programs. 相似文献