18 resultados para survival rate

em Deakin Research Online - Australia


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Black bream (Acanthopagrus butcheri) is the main target species amongst the estuarine recreational fisheries of Victoria, Australia. The A. butcheri fishery is managed through legal-minimum length and daily bag limits. The success of this management strategy requires that the survival rate for released fish is high. This study used the most common angling practices to estimate post-release survival and identify influential factors for undersized A. butcheri in Victoria. In total 1557 and 923 A. butcheri were caught and monitored for initial (≤1 h) and delayed (72 h) survival, respectively. Fish were caught across 3 years, with each year separated into cold and warm water periods with 8 fishing trial days in total. Only 1 of the 266 controls used to assess confinement effects died. Total survival was 95% (S.E. ± 0.8%) for shallow- and 74% (S.E. ± 3%) for deep-hooked fish and decreased as fish length increased. A post-mortem (PM) procedure was developed and showed that throat and gill injuries were the most frequent cause of deep-hooking death. It revealed that 97% of hooks left in fish remained there after 72 h and identified hooking location inaccuracies recorded at the time of capture. Total survival for deep-hooked fish was 20% higher when hooks were left in the fish. Deep-hooked fish were more likely to bleed when hooks were removed and total survival was lower for fish that bleed (58%) than fish that did not bleed (80%). Shallow-hooking rates decreased as fish length increased and were higher during warm water compared to cold water trials. The high shallow-hooking and survival rates observed suggest that A. butcheri survival in the fishery would be high, but deep-hooking has the potential to undermine the management strategy. Determining the shallow-hooking rate in the fishery would help clarify the impact of these findings at the fishery level.

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The black bream Acanthopagrus butcheri recreational fishery is the largest estuarine fishery in Victoria. This fishery is managed through legal-minimum length and daily bag limits. The success of this management strategy requires a high survival rate for released fish. Deep-hooking is known to reduce the chance of fish survival after recreational capture and release. This study investigated the potential to reduce deep-hooking and the number of under-size A. butcheri caught by varying angling gear and techniques. Three sizes of long shank hook (small [size 8], medium [size 4] and large [size 1/0]) and two angling techniques (slack line and tight line) were tested for their deep-hooking rates and selectivity characteristics. Increasing the hook size from small to large decreased the likelihood of deep-hooking by 6.6 times (95% CI 2.3–16.3 times). Fishing with a tight line instead of a slack line decreased the chance of deep-hooking by almost 100% (95% CI 0.8–3.6). Fishing with a large hook instead of a small hook significantly (F = 6.71, df = 2, P = <0.001) increased the mean A. butcheri length, although this mean size increase was less than 1 cm. This study was able to identify angling gear and angling technique manipulations that reduced the rate of deep-hooking when targeting A. butcheri in Victorian estuaries.

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There is expanding interest in the culture of the Australian shortfin eel Anguilla australis Richardson; however, there is a lack of fundamental biology and husbandry information necessary to further develop an industry within Australia. The present study was undertaken to gain a preliminary understanding of basic husbandry requirements for rearing of juvenile A. australis (glass eels and elvers) in tanks and earthen ponds. Newly caught glass eels were successfully acclimated to culture conditions. During tank culture trials, specific growth rates (SGR) and survival rates ranged from −2.1 to 2.8% day−1 and 52% to 100% respectively. Glass eels weaned onto a commercial eel diet exhibited a significantly greater SGR and survival rate than those weaned onto a commercial trout diet. Glass eels weaned onto an eel diet over a 15-day period grew slightly faster than eels weaned over a 5-day period, but survival rates were not significantly different for each treatment. SGRs (up to 2.8% day−1) were significantly higher for glass eels fed at 9 and 12% day−1 than at 6% day−1. Stocking densities between 2.5 kg m−3 and 30 kg m−3 did not influence either SGR or survival rates. SGRs were significantly higher for glass eels cultured at 25 °C than at lower temperatures. During pond culture trials, SGRs and survival rates ranged from 1.36 to 1.65% day−1 and 39% to 77% respectively. The SGR and survival rates of juvenile eels stocked into ponds receiving supplementary feeding with a commercial eel diet were not significantly different to those of eels stocked into ponds that did not receive supplementary feeding.

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Artificial chick shelters might improve productivity of beach-nesting birds threatened by anthropogenic disturbance. We investigated the efficacy of three different chick shelter designs against four criteria: accessibility to chicks over time, thermal insulation, conspicuousness to beach-goers, and practicality (cost and ease of transport). One design (‘A-frame’) was selected because it offered the greatest thermal insulation, was the least conspicuous, most cost effective, and performed equally well in terms of accessibility. We deployed these artificial shelters on Hooded Plover Thinornis rubricollis territories where broods were present (n 5 11), and compared the behaviour and survival rate of chicks to that at control sites (n 5 10). We were unable to discern any difference in the behaviour of broods when artificial shelters were available. However, the survival rate of chicks to fledging was 71.8% higher where an artificial shelter was provided (n 5 21 broods). This was validated by analysing data from a larger sample of broods monitored as part of an active volunteer-based management programme; shelters conferred a 42.8%increase in survival to fledging (n 5 81 broods). Thus, artificial shelters have the potential to increase survival rates of threatened shorebird chicks, though the mechanisms through which survival is increased require further investigation.

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Nutrient discharge into coastal areas, such as the Great Barrier Reef can result in the degradation of coastal ecosystems. For example, excess nitrogen and phosphorus can damage corals through inducing algal bloom and subsequent shading. Excessive phosphorus can further weaken coral skeletons making them susceptible to damage. Land based industries such as aquaculture can contribute to such problems. This study set out to develop a system whereby water from aquaculture can be constantly reused resulting in minimized waste discharge. A three-stage filtration system utilizing floating media and activated carbon was designed to harness bacterial processes that could reduce both particulate and dissolved compounds to the extent whereby approximately 100% reuse of the wastewater became possible. This involved efficient and effective particulate and biological removal mechanisms in both aerobic and anaerobic zones of the filtration system. This design reduced dissolved nitrogen levels by up to 70% and maintained low phosphorus levels, which allowed the reuse of water for the successful culture of barramundi with a survival rate of 97% over 25 days. This pilot scale study demonstrated the potential of reusing aquaculture wastewater from the viewpoint of reducing nutrient input into coastal environments. Future research will refine these processes and assess the performance of the system at several commercial scale applications.

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Background In this phase II trial, we investigated the efficacy of a metronomic temozolomide schedule in the treatment of recurrent malignant gliomas (MGs).

Methods Eligible patients received daily temozolomide (50 mg/m2) continuously until progression. The primary endpoint was progression-free survival rate at 6 months in the glioblastoma cohort (N = 37). In an exploratory analysis, 10 additional recurrent grade III MG patients were enrolled. Correlative studies included evaluation of 76 frequent mutations in glioblastoma (iPLEX assay, Sequenom) aiming at establishing the frequency of potentially “drugable” mutations in patients entering recurrent MG clinical trials.

Results Among glioblastoma patients, median age was 56 y; median Karnofsky Performance Score (KPS) was 80; 62% of patients had been treated for ≥2 recurrences, including 49% of patients having failed bevacizumab. Treatment was well tolerated; clinical benefit (complete response + partial response + stable disease) was seen in 10 (36%) patients. Progression-free survival rate at 6 months was 19% and median overall survival was 7 months. Patients with previous bevacizumab exposure survived significantly less than bevacizumab-naive patients (median overall survival: 4.3 mo vs 13 mo; hazard ratio = 3.2; P = .001), but those patients had lower KPS (P = .04) and higher number of recurrences (P < .0001). Mutations were found in 13 of the 38 MGs tested, including mutations of EGFR (N = 10), IDH1 (N = 5), and ERBB2 (N = 1).

Conclusions In spite of a heavily pretreated population, including nearly half of patients having failed bevacizumab, the primary endpoint was met, suggesting that this regimen deserves further investigation. Results in bevacizumab-naive patients seemed particularly favorable, while results in bevacizumab-failing patients highlight the need to develop further treatment strategies for advanced MG.

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Considerable variability in survival rate after an acute myocardial infarction exists and accurate risk stratification is of significant importance. The American College of Cardiology and the American Heart Association has recommended early risk stratification using several clinical risk scoring instruments to identify high risk patients. The aim of this paper is to identify secondary cardiovascular risk scoring instruments that could be utilized at the time of intervention for acute coronary syndromes and compare their psychometric properties as they were developed. A search using Medline, Cumulative Index to Nursing and Allied Health Literature and the Psychology and Behavioral Sciences Collection data-bases identified studies published between January 1990 and January 2010 used to measure risk after intervention for acute coronary syndrome. Four validated secondary risk prediction scoring instruments were identified for comparison.Secondary risk prediction scoring instruments for the acute coronary syndrome patient population are evidence based, valid and reliable. Use of the instruments by cardiac focused clinicians will aid in the determination of treatment strategies, and estimation of short and long term events and mortality.

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 Some ground-nesting birds adopt a mixed strategy of nesting in the open, or under cover (e.g. vegetation). This may represent a trade-off between thermally favourable nest sites (covered) and those that enable the early detection and avoidance of predators (open). This study examined whether such a trade-off exists for Redcapped Plover Charadrius ruficapillus, whose eggs are preyed upon principally by Little Raven Corvus mellori. For real and artificial nests, nest temperatures under cover (real, 25.9 ± 0.1°C; false, 16.2 ± 0.5°C) were cooler than those in the open (real, 26.8 ± 0.1°C; false, 17.4 ± 0.9°C). Covered nests had more visual obstructions than open nests (covered, 65.5% ± 11.4%; open, 7.4% ± 2.8%) and a standardised measure of incubator escape distance, initiated by experimental human approaches, indicated incubators fled open nests at longer distances than for covered nests. Nests under cover showed a slightly (non-significant) higher probability of surviving one day (Daily Survival Rate [DSR] = 0.978) than those in the open (DSR = 0.950). For false nests containing model eggs, covered nests exhibited better survival to 10 days compared with open nests (20.4% vs. 4.7%). Thus, covered nests are associated with enhanced thermal environments and egg survival, but predators can approach the incubator more closely. Overall, the proposed trade-off between thermal and predation risks associated with nest sites appears to exist and explains the ongoing occurrence of nests in open and covered locations.

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This is the first ever attempt to combine anti-cancer therapeutic effects of emerging anticancer biodrug bovine lactoferrin (bLf), and multimodal imaging efficacy of Fe3O4 nanoparticles (NPs) together, as a saturated Fe3O4-bLf. For cancer stem cell specific uptake of nanocapsules/nanocarriers (NCs), Fe3O4-bLf was encapsulated in alginate enclosed chitosan coated calcium phosphate (AEC-CP) NCs targeted (Tar) with locked nucleic acid (LNA) modified aptamers against epithelial cell adhesion molecule (EpCAM) and nucleolin markers. The nanoformulation was fed orally to mice injected with triple positive (EpCAM, CD133, CD44) sorted colon cancer stem cells in the xenograft cancer stem cell mice model. The complete regression of tumor was observed in 70% of mice fed on non-targeted (NT) NCs, with 30% mice showing tumor recurrence after 30 days, while only 10% mice fed with Tar NCs showed tumor recurrence indicating a significantly higher survival rate. From tumor tissue analyses of 35 apoptotic markers, 55 angiogenesis markers, 40 cytokines, 15 stem cell markers and gene expression studies of important signaling molecules, it was revealed that the anti-cancer mechanism of Fe3O4-bLf was intervened through TRAIL, Fas, Fas-associated protein with death domain (FADD) mediated phosphorylation of p53, to induce activation of second mitochondria-derived activator of caspases (SMAC)/DIABLO (inhibiting survivin) and mitochondrial depolarization leading to release of cytochrome C. Induction of apoptosis was observed by inhibition of the Akt pathway and activation of cytokines released from monocytes/macrophages and dendritic cells (interleukin (IL) 27, keratinocyte chemoattractant (KC)). On the other hand, the recurrence of tumor in AEC-CP-Fe3O4-bLf NCs fed mice mainly occurred due to activation of alternative pathways such as mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinases (ERK) and Wnt signaling leading to an increase in expression of survivin, survivin splice variant (survivin 2B) and other anti-apoptotic proteins Bad, Bcl-2 and XIAP. Apart from the promising anti-cancer efficacy and the exceptional tumor targeting ability observed by multimodal imaging using near-infrared (NIR) imaging, magnetic resonance imaging (MRI) and computerized tomographic (CT) techniques, these NCs also maintained the immunomodulatory benefits of bLf as they were able to increase the RBC, hemoglobin, iron calcium and zinc levels in mice.

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OBJECTIVE: With improvements in cardiovascular disease (CVD) rates among people with diabetes, mortality rates may also be changing. However, these trends may be influenced by coding practices of CVD-related deaths on death certificates. We analyzed trends of mortality over 13 years in people with diabetes and quantified the potential misclassification of CVD mortality according to current coding methods. RESEARCH DESIGN AND METHODS: A total of 1,136,617 Australians with diabetes registered on the National Diabetes Services Scheme between 1997 and 2010 were linked to the National Death Index. Excess mortality relative to the Australian population was reported as standardized mortality ratios (SMRs). Potential misclassification of CVD mortality was determined by coding CVD according to underlying cause of death (COD) and then after consideration of both the underlying and other causes listed in part I of the death certificate. RESULTS: For type 1 diabetes, the SMR decreased in males from 4.20 in 1997 to 3.08 in 2010 (Ptrend < 0.001) and from 3.92 to 3.46 in females (Ptrend < 0.01). For type 2 diabetes, the SMR decreased in males from 1.40 to 1.21 (Ptrend < 0.001) and from 1.56 to 1.22 in females (Ptrend < 0.001). CVD deaths decreased from 35.6 to 31.2% and from 31.5 to 27.2% in males and females with type 1 diabetes, respectively (Ptrend < 0.001 for both sexes). For type 2 diabetes, CVD decreased from 44.5 to 29.2% in males and from 45.5 to 31.6% in females (Ptrend < 0.001 for both sexes). Using traditional coding methods, ∼38 and 26% of CVD deaths are underestimated in type 1 diabetes and type 2 diabetes, respectively. CONCLUSIONS: All-cause and CVD mortality has decreased in diabetes. However, the total CVD mortality burden is underestimated when only underlying COD is considered. This has important ramifications for understanding mortality patterns in diabetes.

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BACKGROUND: Differences in demographics, presenting characteristics, and treatment of heart disease in women may contribute to adverse outcomes. The purpose of this paper was to describe gender differences in the epidemiology, treatment, and outcomes of all admissions for acute coronary syndrome (ACS) in Victoria that occurred between June 2007 and July 2009. METHODS: We undertook a retrospective cohort study of all patients admitted to Victorian hospitals with a first time diagnosis of ACS. Use of angiograms, percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), and adverse outcomes (death and/or unplanned readmission) were compared by gender and hierarchical logistic regression models were used to account for confounding variables. RESULTS: Of a total of 28,985 ACS patients, 10,455 (36%) were women. Compared with men, women were older (aged ≥75 years: 54% vs 31%; p < .001), more likely to present with multiple comorbidities (>1 comorbidity: 53% vs 46%; p < .001), and more likely to be diagnosed with non-ST-segment elevation ACS (86% vs 80%; p < .001). Women were less likely to receive coronary interventions (angiogram: adjusted odds ratio [aOR], 0.71; 95% CI, 0.66-0.75; PCI: aOR, 0.73; 95% CI, 0.66-0.80; CABG: aOR, 0.58; 95% CI, 0.53-0.64). Adverse outcomes were similar in women and men after accounting for confounding variables. CONCLUSIONS: Our results show that women in Victoria were less likely to receive coronary interventions after an admission for ACS. Clinicians should be wary of inherent gender bias in decisions to refer patients for angiography.

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Coastal birds are critical ecosystem constituents on sandy shores, yet are threatened by depressed reproductive success resulting from direct and indirect anthropogenic and natural pressures. Few studies examine clutch fate across the wide range of environments experienced by birds; instead, most focus at the small site scale. We examine survival of model shorebird clutches as an index of true clutch survival at a regional scale (∼200 km), encompassing a variety of geomorphologies, predator communities, and human use regimes in southeast Queensland, Australia. Of the 132 model nests deployed and monitored with cameras, 45 (34%) survived the experimental exposure period. Thirty-five (27%) were lost to flooding, 32 (24%) were depredated, nine (7%) buried by sand, seven (5%) destroyed by people, three (2%) failed by unknown causes, and one (1%) was destroyed by a dog. Clutch fate differed substantially among regions, particularly with respect to losses from flooding and predation. ‘Topographic’ exposure was the main driver of mortality of nests placed close to the drift line near the base of dunes, which were lost to waves (particularly during storms) and to a lesser extent depredation. Predators determined the fate of clutches not lost to waves, with the depredation probability largely influenced by region. Depredation probability declined as nests were backed by higher dunes and were placed closer to vegetation. This study emphasizes the scale at which clutch fate and survival varies within a regional context, the prominence of corvids as egg predators, the significant role of flooding as a source of nest loss, and the multiple trade-offs faced by beach-nesting birds and those that manage them.

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BACKGROUND: We describe a retrospective series of children with low-grade glioma who received temozolomide. PROCEDURE: Eligible patients had had a diagnosis of low-grade glioma with or without histological confirmation. Temozolomide was administered at a dose of 200 mg/m(2) daily for 5 days, in a 4-week cycle. Therapy was stopped on completion of the targeted 12 cycles of chemotherapy or on evidence of tumor progression. RESULTS: Thirteen eligible patients were identified, eight male and five female. Median age at diagnosis was 5.5 years (range 2.6-15.0 years) and at commencement of temozolomide treatment was 9.0 years (range 3.8-15.2 years). Nine patients had a histological diagnosis of pilocytic astrocytoma. Twelve patients had received carboplatin prior to temozolomide, including three in combination with vincristine. A total of 111 cycles of therapy have been administered. Hematological toxicity and nausea were the most common adverse effects. Median time to progression was 6.7 months (range 1.5-41.8 months). Event-free survival rate at 3 years was 57%. Twelve of 13 patients remain alive at the time of report. Eleven have stable disease (SD). CONCLUSION: Temozolomide appears to be active in pediatric low-grade glioma, with the advantage of oral administration and excellent tolerability.

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Individual specialization is widespread among wild populations. While its fitness consequences are central in predicting the ecological and evolutionary trajectories of populations, they remain poorly understood. Long-term individual foraging specializations occur in male Antarctic (Arctocephalus gazella) and Australian (A. pusillus doriferus) fur seals. Strong selective pressure is expected in these highly dimorphic and polygynous species, raising the question of the fitness payoffs associated with different foraging strategies. We investigated the relationship between individual isotopic niche (a proxy of foraging specialization), body size and condition, and an index of reproductive success (harem size) in territorial males. Individuals varied greatly in their skin and fur isotopic values reflecting a range of foraging strategies within the two populations. However, in both species, isotopic niche was not correlated to body size, condition or mating success (R (2)/ρ < 0.06). Furthermore, no foraging niche was predominant in either species, which would have indicated a substantial long-term fitness benefit of a particular strategy via a higher survival rate. These results suggest that the fitness consequences of a foraging strategy depend not only on the quality of prey and feeding habitat but also on an individual's hunting efficiency and skills.

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Background
The aim of this study was to describe the clinical characteristics, causative pathogens, clinical management and outcomes of patients presenting to a tertiary adult Australian intensive care unit (ICU) with a diagnosis of necrotizing fasciitis (NF).
Methods
This retrospective observational study was conducted in a 19-bed, level III, adult ICU in a 450-bed tertiary, regional hospital. Clinical databases were accessed for patients diagnosed with NF and admitted to The Geelong Hospital ICU between 1 February 2000 and 1 June 2011. Information on severity of sepsis, surgical procedures and microbiological results were collected.
Results
Twenty patients with NF were identified. The median age was 52.5 years and 38% were female. The overall mortality rate was 8.3%. Common co-morbidities were diabetes (21%) and heart failure (17%), although 50% of patients had no co-morbidities. Group A Streptococcus was the identified pathogen in 11 (46%) patients, and Streptococcus milleri group in 5 (21%) patients. Hyperbaric oxygen therapy was not used in the majority of patients. The initial antibiotics administered were active against subsequently cultured bacteria in 83% of patients. Median time to surgical debridement was 20 h. Diagnosis and management was delayed in the nosocomial group.
Conclusions
This study reports physiological data, aetiology and therapeutic interventions in NF for an adult tertiary hospital. We demonstrate one of the lowest reported mortality rates, with early surgical debridement being achieved in the majority of patients. The main delay was found to be in the diagnosis of NF.