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1.
Transbound Emerg Dis ; 68(4): 2295-2307, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33085823

ABSTRACT

Viral haemorrhagic septicaemia virus (VHSV) and infectious haematopoietic necrosis virus (IHNV) are important viral pathogens posing a serious threat to salmonid fish. Survival of two isolates of IHNV and one of VHSV was assessed at temperatures ranging from 4 to 25°C: (a) after drying on stainless steel, (b) in cell culture medium, (c) in filtered river water, (d) in unfiltered river water, and (e) survival, adsorption and desorption in river sediment and five typical soil types. The viruses survived 1 hr to > 84 days depending on the conditions. Survival was inversely related to temperature and organic and inorganic content. Both viruses remained infectious after being dried on stainless steel for several weeks highlighting the risk of mechanical transmission and persistence in a dry environment. Both adsorbed to the soils from the river water inoculum, with titres between 5.56x104 and 2.58x108 TCID50 /ml after 1 hr. Clay soils adsorbed the least virus but had the greatest decrease in the river water inoculum (undetectable in ≤ 1 hr), and there was no desorption. Virus desorbed from the other soils into the surrounding water at different rates dependant on soil type (longest desorption was from chalk loam and sandy soil-detected at 28 days). When desorption was no longer detectable, virus persisted, adsorbed to the soil and remained infectious (the longest adsorption was detected in clay loam for ≥ 49 days, but all the viruses adsorbed to soils were likely to have survived longer than that detected, based on their rate of decay). The long survival of the viruses, particularly at cooler temperatures, highlights the risk of survival in the environment and waterborne spread. The data presented here are highly relevant for assessing risk of pathogen introduction via fomites (stainless steel) and for deciding on best control measures in the context of disease outbreaks.


Subject(s)
Fish Diseases , Infectious hematopoietic necrosis virus , Novirhabdovirus , Animals , Fresh Water , Soil , Stainless Steel
2.
Vaccine ; 24(23): 4927-33, 2006 Jun 05.
Article in English | MEDLINE | ID: mdl-16650915

ABSTRACT

Several DNA constructs containing the spring viraemia of carp virus (SVCV) glycoprotein (G) gene were investigated for their ability to induce protection against SVCV following injection into myofibres. The constructs were pooled into four groups and co-injected with a plasmid encoding murine granulocyte-macrophage colony-stimulating factor. Group 1 contained one full-length and two truncated G constructs under the control of the cytomegalovirus (CMV) promoter. Group 2 contained full-length constructs with the CMV promoter, the simian virus 40 promoter and a muscle-specific promoter. Group 3 contained constructs in which the G-gene was fused with a second gene in order to improve secretion of the G-protein or to enhance destruction of transfected myocytes by T cells. Group 4 contained constructs with the CMV-Intron A promoter in plasmids with or without CpG motifs. A small-scale trial in goldfish showed that antibody responses in at least half the fish were induced by three injections of plasmids from Groups 1 and 3 whereas T-cell like responses with stimulation indices of above 3 were induced in at least half the fish by Groups 2 and 4. A single-dose of each plasmid mix was then used to protect carp in a large-scale trial. Following challenge with a heterologous strain of SVCV that killed 64% of fish, the strongest protection was observed in carp that received the full length G-gene expressed by two plasmids driven by the CMV-Intron A promoter (Group 4), with a relative percentage survival of 48% (p=0.00008).


Subject(s)
Carps/immunology , Carps/virology , Fish Diseases/prevention & control , Fish Diseases/virology , Vaccines, DNA/immunology , Viral Vaccines/immunology , Viremia/veterinary , Virus Diseases/veterinary , Animals , Fish Diseases/immunology , Seasons , Viremia/immunology , Viremia/prevention & control , Virus Diseases/immunology , Virus Diseases/prevention & control
3.
Int J Radiat Oncol Biol Phys ; 64(4): 1002-12, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16414205

ABSTRACT

PURPOSE: This population-based study describes the treatment of early glottic cancer in Ontario, Canada and assesses whether treatment variations were associated with treatment effectiveness. METHODS AND MATERIALS: We studied 491 T1N0 and 213 T2N0 patients. Data abstracted from charts included age, sex, stage, treatment details, disease control, and survival. RESULTS: The total dose ranged from 50 to 70 Gy, and the daily dose ranged from 1.9 to 2.8 Gy. In 90%, treatment duration was between 25 and 50 days. Field sizes, field reductions, beam arrangement, and beam energy varied. Late treatment breaks occurred in 13.6% of T1N0 and 27.1% of T2N0 cases. Local control was comparable to other reports for T1N0 (82% at 5 years), but was only 63.2% in T2N0. Variables associated with local failure in T1N0 were age less than 49 years (relative risk [RR], 3.21; 95% confidence interval [CI], 1.49-6.90) and >3 treatment interruption days (RR, 2.43; 95% CI, 1.00-5.91). In T2N0, these were field reduction (RR, 2.33; 95% CI, 1.23-4.42) and late treatment breaks (RR, 2.19; 95% CI, 1.09-4.41). CONCLUSION: Some aspects of treatment for early glottic cancer were associated with worse local control. Problems with protracted treatment are of particular concern, underscoring the need for randomized studies to intensify radiotherapy.


Subject(s)
Carcinoma, Squamous Cell/radiotherapy , Glottis , Laryngeal Neoplasms/radiotherapy , Age Factors , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Confidence Intervals , Dose Fractionation, Radiation , Humans , Laryngeal Neoplasms/pathology , Middle Aged , Neoplasm Staging , Ontario , Regression Analysis , Retrospective Studies , Treatment Outcome
4.
J Clin Oncol ; 21(3): 496-505, 2003 Feb 01.
Article in English | MEDLINE | ID: mdl-12560441

ABSTRACT

PURPOSE: We compared the management and outcome of supraglottic cancer in Ontario, Canada, with that in the Surveillance, Epidemiology, and End Results (SEER) Program areas in the United States. METHODS: Electronic, clinical, and hospital data were linked to cancer registry data and supplemented by chart review where necessary. Stage-stratified analyses compared initial treatment and survival in the SEER areas (n = 1,643) with a random sample from Ontario (n = 265). We also compared laryngectomy rates at 3 years in those patients 65 years and older at diagnosis. RESULTS: Radical surgery was more commonly used in SEER, with absolute differences increasing with increasing stage: I/II, 17%; III, 36%; and IV, 45%. The 5-year survival rates were 74% in Ontario and 56% in SEER for stage I/II disease (P =.01), 55.7% in Ontario and 46.8% in SEER for stage III disease (P =.40), and 28.5% in Ontario and 29.1% in SEER for stage IV disease (P =.28). Cancer-specific survival results mirrored the overall survival results with the exception of stage IV disease, for which 34.6% of Ontario patients survived their cancer compared with 38.1% in SEER (P =.10). This stage IV difference was more pronounced when we further controlled for possible cause of death errors by restricting the comparison to patients with a single primary cancer (P =.01). Three-year actuarial laryngectomy rates differed. In stage I/II, these rates were 3% in Ontario compared with 35% in SEER (P < 10(-3)). In stage III disease, the rates were 30% and 54%, respectively (P =.03), and in stage IV disease they were 33% and 64% (P =.002). CONCLUSION: There are large differences in the management of supraglottic cancer between the SEER areas of the United States and Ontario. Long-term larynx retention was higher in Ontario, where radiotherapy is widely regarded as the treatment of choice and surgery is reserved for salvage. In stages I to III, survival was similar in the two regions despite the differences in treatment policy. In stage IV, there may be a small survival advantage in the U.S. SEER areas related to the higher use of primary surgery.


Subject(s)
Laryngeal Neoplasms/pathology , Laryngeal Neoplasms/surgery , Laryngectomy , Practice Patterns, Physicians' , SEER Program , Aged , Cohort Studies , Female , Humans , Male , Middle Aged , Neoplasm Staging , Ontario , Prognosis , Retrospective Studies , Survival , United States
5.
J Clin Epidemiol ; 55(6): 533-44, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12063095

ABSTRACT

The combination of T, N, and M classifications into stage groupings is meant to facilitate a number of activities including: the estimation of prognosis and the comparison of therapeutic interventions among similar groups of cases. We tested the UICC/AJCC fifth edition stage grouping and six other TNM-based groupings proposed for head and neck cancer for their ability to meet these expectations in laryngeal cancer using data from Ontario, Canada, and the area of Southern Norway surrounding Oslo. We defined four criteria to assess each grouping scheme: (1) the subgroups defined by T, N, and M comprising a given group within a grouping scheme have similar survival rates (hazard consistency); (2) the survival rates differ among the groups (hazard discrimination); (3) the prediction of cure is high (outcome prediction); and (4) the distribution of patients among the groups is balanced. We previously identified or derived a measure for each criterion, and the findings were summarized using a scoring system. The range of scores was from 0 (best) to 7 (worst). The data sets were population-based, with 861 cases from Ontario and 642 cases from Southern Norway. Clinical stage assignment was used and the outcome of interest was cause-specific survival. Summary scores across the seven schemes had similar ranges: 0.9 to 5.1 in Ontario and 1.8 to 5.7 in Southern Norway, but the ranking varied. Summing the scores across the two datasets, the TANIS-7 scheme (Head & Neck 1993;15:497-503) ranked first, and was ranked high in both datasets (first and second, respectively). The UICC/AJCC scheme ranked sixth out of seven schemes, and its ranking was fifth and seventh, respectively. UICC/AJCC stage groupings were defined without empirical investigation. When tested, this scheme did not perform best. Our results suggest that the usefulness of the TNM system could be enhanced by optimizing the design of stage groupings through empirical investigation.


Subject(s)
Carcinoma, Squamous Cell/classification , Carcinoma, Squamous Cell/pathology , Head and Neck Neoplasms/classification , Laryngeal Neoplasms/classification , Laryngeal Neoplasms/pathology , Neoplasm Staging/methods , Carcinoma, Squamous Cell/epidemiology , Disease Progression , Disease-Free Survival , Head and Neck Neoplasms/pathology , Humans , Laryngeal Neoplasms/epidemiology , Norway/epidemiology , Odds Ratio , Ontario/epidemiology , Prognosis , Proportional Hazards Models , Reproducibility of Results , Retrospective Studies , Survival Analysis
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