10 research outputs found
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Monitoring Focal Laser Ablation of Prostate Cancer with Interstitial Thermal and Optical Probes
Prostate cancer is diagnosed in almost 200,000 men in the U.S. annually. With approximately 30,000 deaths, the mortality to incidence ratio is relatively low in comparison to other common cancers. Moreover, the primary treatment modalities, radical prostatectomy and radiation therapy, are associated with a substantial reduction in quality of life. Consequently, there is a growing interest in focal therapy which aims to treat the target tumor while minimizing damage to surrounding tissue.Focal laser ablation (FLA) is a form of focal therapy in which a laser fiber is inserted into a target tumor and oncologic control is achieved through thermally induced coagulative necrosis. Many groups have performed FLA using magnetic resonance imaging (MRI) for laser fiber targeting and real-time feedback. While this approach has shown promise, we contend that the resource intensive nature of MRI will forever preclude widespread adoption of FLA.This thesis presents a concerted effort to translate FLA from the MRI suite to the urology clinic. To this end we performed a clinical trial using magnetic resonance – ultrasound fusion guidance and interstitial thermal probes for treatment targeting and monitoring respectively. This approach proved to be safe and potentially effective; however, the utility of thermal probes was found to be inherently limited due to the need for empirically derived thermal damage models.In an effort to provide an improved monitoring modality we developed an interstitial optical monitoring system that directly assesses the state of tissue based on laser-tissue interaction. To correlate the optical signal and the growth of the coagulation zone we created a tissue mimicking phantom which simulates the thermal and optical response of prostatic tissue and facilitates visualization of the coagulation zone on MRI. FLA was performed in the phantom under MRI surveillance with simultaneous interstitial optical monitoring resulting in the development of a real-time feedback algorithm. The algorithm was subsequently tested in ex vivo bovine tissue and was capable of identifying the coagulation border with a mean absolute error of 0.3�0.1mm. Further work is necessary to demonstrate the utility of interstitial optical monitoring in vivo
Wdrożenie nauczania przez odkrywanie do polskiej podstawy programowej w zakresie przedmiotów przyrodniczych : badanie opinii nauczycieli
The new Polish science curriculum was launched in the 2008 and currently is being implemented in
upper secondary schools. The new general objectives of education, and students’ key competences that should be
developed during science classes were defined in that document. Presented competences are in line with
competences that might be developed by Inquiry Based Science Education (IBSE). IBSE is currently a popular
instructional method in many countries and it is being strongly promoted by European Union. In the article the
role of IBSE in the new Polish science curriculum is described and related to the method of ‘Independent
Investigation to Acquire Knowledge’ that was formerly known in the national pedagogy. The article also presents
results of a survey questionnaire that was conducted among Polish science teachers. The aim of the study was to
measure the attitude of Polish teachers, pupils and society to IBSE. Based on the results the current position and
degree of implementation of IBSE in Polish schools was estimated. Additionally the positive and negative factors
affecting the implementation of IBSE were presente
Cytosine methylation is a conserved epigenetic feature found throughout the phylum Platyhelminthes
BACKGROUND: The phylum Platyhelminthes (flatworms) contains an important group of bilaterian organisms responsible for many debilitating and chronic infectious diseases of human and animal populations inhabiting the planet today. In addition to their biomedical and veterinary relevance, some platyhelminths are also frequently used models for understanding tissue regeneration and stem cell biology. Therefore, the molecular (genetic and epigenetic) characteristics that underlie trophic specialism, pathogenicity or developmental maturation are likely to be pivotal in our continued studies of this important metazoan group. Indeed, in contrast to earlier studies that failed to detect evidence of cytosine or adenine methylation in parasitic flatworm taxa, our laboratory has recently defined a critical role for cytosine methylation in Schistosoma mansoni oviposition, egg maturation and ovarian development. Thus, in order to identify whether this epigenetic modification features in other platyhelminth species or is a novelty of S. mansoni, we conducted a study simultaneously surveying for DNA methylation machinery components and DNA methylation marks throughout the phylum using both parasitic and non-parasitic representatives. RESULTS: Firstly, using both S. mansoni DNA methyltransferase 2 (SmDNMT2) and methyl-CpG binding domain protein (SmMBD) as query sequences, we illustrate that essential DNA methylation machinery components are well conserved throughout the phylum. Secondly, using both molecular (methylation specific amplification polymorphism, MSAP) and immunological (enzyme-linked immunoabsorbent assay, ELISA) methodologies, we demonstrate that representative species (Echinococcus multilocularis, Protopolystoma xenopodis, Schistosoma haematobium, Schistosoma japonicum, Fasciola hepatica and Polycelis nigra) within all four platyhelminth classes (Cestoda, Monogenea, Trematoda and ‘Turbellaria’) contain methylated cytosines within their genome compartments. CONCLUSIONS: Collectively, these findings provide the first direct evidence for a functionally conserved and enzymatically active DNA methylation system throughout the Platyhelminthes. Defining how this epigenetic feature shapes phenotypic diversity and development within the phylum represents an exciting new area of metazoan biology
Effects of the North Atlantic Oscillation on growth and phenology of stream insects
Climatic variation associated with the North Atlantic Oscillation (NAO) influences terrestrial and marine ecosystems, but its effects on river and stream ecosystems are less well known. The influence of the NAO on the growth of stream insects was examined using long-term empirical data on the sizes of mayfly and stonefly nymphs and on water temperature data. Models of egg development and nymphal growth in relation to temperature were used to predict the effect of the NAO on phenology. The study was based in two upland streams in mid-Wales UK that varied in the extent of plantation forestry in their catchments. Winter stream temperatures at both sites were positively related to the winter NAO index, being warmer in positive phases and colder in negative phases. The observed mean size and the simulated developmental period of mayfly nymphs were significantly related to the winter NAO index, with nymphs growing faster in positive phases of the NAO, but the growth of stonefly nymphs was not related to the NAO. This may have been due to the semivoltine stonefly lifecycle, but stonefly nymph growth is also generally less dependent on temperature. There were significant differences in growth rates of both species between streams, with nymphs growing more slowly in the forested stream that was consistently cooler than the open stream. Predicted emergence dates for adult mayflies varied by nearly two months between years, depending on the phase of the NAO. Variation in growth and phenology of stream insects associated with the NAO may influence temporal fluctuations in the composition and dynamics of stream communities
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Interstitial Optical Monitoring of Focal Laser Ablation.
Focal laser ablation is a minimally invasive method of treating cancerous lesions in organs such as prostate, liver and brain. Oncologic control is achieved by inducing hyperthermia throughout the target while minimizing damage to surrounding tissue. Consequently, successful clinical outcomes are contingent upon achieving desired ablation volumes. Magnetic resonance thermometry is frequently used to monitor the formation of the induced thermal damage zone and inform the decision to terminate energy delivery. However, due to the associated cost and complexity there is growing interest in the development of alternative approaches. Here we investigate the utility of real-time interstitial interrogation of laser-tissue interaction as an inexpensive alternative monitoring modality that provides direct assessment of tissue coagulation without the need for organ specific calibration. The optical contrast mechanism was determined using a Monte Carlo model. Subsequently, four interstitial probe designs were manufactured and assessed in a tissue mimicking phantom under simultaneous magnetic resonance imaging. Finally, the optimal probe design was evaluated in ex vivo bovine muscle. It was found to be capable of providing sufficient feedback to achieve pre-defined ablation radii in the range 4-7 mm with a mean absolute error of 0.3 mm. This approach provides an inexpensive monitoring modality that may facilitate widespread adoption of focal laser ablation
Inter-population dispersal by adult stoneflies detected by stable isotope enrichment
1. Dispersal of adult stream insects may be of considerable importance in regional population dynamics and colonisation of new sites, but quantifying the rate and extent of dispersal is difficult.2. We used stable isotope (15N) enrichment to mark more than 1.5 million larval stoneflies (Leuctra inermis) before they emerged from an upland stream in the Plynlimon area of mid-Wales, in order to determine directly the rate and pattern of inter-site dispersal. 3. A small number of isotopically enriched adult stoneflies were captured in samples taken at adjacent streams between 800m and 1.1km away from the source population, including a headwater of a different river system.4. The distribution of marked individuals suggested that wind influences dispersal direction in the uplands, but the low number of captures limits our ability to draw firm conclusions.5. This is the first direct demonstration of dispersal of insects between streams. The dispersal distances recorded were significantly greater than those suggested by previous direct studies, but much more consistent with indirect studies based on genetic differentiation of populations
A randomized, double-blind, placebo-controlled trial of intravenous alpha-1 antitrypsin for ARDS secondary to COVID-19
Background: Patients with severe coronavirus disease 2019 (COVID-19) develop a febrile pro-inflammatory cytokinemia with accelerated progression to acute respiratory distress syndrome (ARDS). Here we report the results of a phase 2, multicenter, randomized, double-blind, placebo-controlled trial of intravenous (IV) plasma-purified alpha-1 antitrypsin (AAT) for moderate to severe ARDS secondary to COVID-19 (EudraCT 2020-001391-15).Â
Methods: Patients (n = 36) were randomized to receive weekly placebo, weekly AAT (Prolastin, Grifols, S.A.; 120 mg/kg), or AAT once followed by weekly placebo. The primary endpoint was the change in plasma interleukin (IL)-6 concentration at 1 week. In addition to assessing safety and tolerability, changes in plasma levels of IL-1β, IL-8, IL-10, and soluble tumor necrosis factor receptor 1 (sTNFR1) and clinical outcomes were assessed as secondary endpoints.Â
Findings: Treatment with IV AAT resulted in decreased inflammation and was safe and well tolerated. The study met its primary endpoint, with decreased circulating IL-6 concentrations at 1 week in the treatment group. This was in contrast to the placebo group, where IL-6 was increased. Similarly, plasma sTNFR1 was substantially decreased in the treatment group while remaining unchanged in patients receiving placebo. IV AAT did not definitively reduce levels of IL-1β, IL-8, and IL-10. No difference in mortality or ventilator-free days was observed between groups, although a trend toward decreased time on ventilator was observed in AAT-treated patients.Â
Conclusions: In patients with COVID-19 and moderate to severe ARDS, treatment with IV AAT was safe, feasible, and biochemically efficacious. The data support progression to a phase 3 trial and prompt further investigation of AAT as an anti-inflammatory therapeutic.Â
Funding: ECSA-2020-009; Elaine Galwey Research Bursary.</p
Characterization of the inflammatory response to severe COVID-19 illness.
Rationale: Coronavirus disease (COVID-19) is a global
threat to health. Its inflammatory characteristics are incompletely understood. Objectives: To define the cytokine profile of COVID-19
and to identify evidence of immunometabolic alterations in those with severe
illness. Methods: Levels of IL-1β, IL-6, IL-8, IL-10, and
sTNFR1 (soluble tumor necrosis factor receptor 1) were assessed in plasma from
healthy volunteers, hospitalized but stable patients with COVID-19 (COVIDstable patients), patients with COVID-19 requiring
ICU admission (COVIDICU patients), and patients with severe
community-acquired pneumonia requiring ICU support (CAPICU patients). Immunometabolic markers were
measured in circulating neutrophils from patients with severe COVID-19. The
acute phase response of AAT (alpha-1 antitrypsin) to COVID-19 was also
evaluated. Measurements and Main
Results: IL-1β, IL-6, IL-8, and sTNFR1 were all
increased in patients with COVID-19. COVIDICU patients could be clearly differentiated
from COVIDstable patients, and demonstrated higher levels of
IL-1β, IL-6, and sTNFR1 but lower IL-10 than CAPICU patients. COVID-19 neutrophils displayed
altered immunometabolism, with increased cytosolic PKM2 (pyruvate kinase M2),
phosphorylated PKM2, HIF-1α (hypoxia-inducible factor-1α), and lactate. The production
and sialylation of AAT increased in COVID-19, but this antiinflammatory
response was overwhelmed in severe illness, with the IL-6:AAT ratio markedly
higher in patients requiring ICU admission (P < 0.0001). In critically unwell patients
with COVID-19, increases in IL-6:AAT predicted prolonged ICU stay and
mortality, whereas improvement in IL-6:AAT was associated with clinical
resolution (P
Conclusions: The COVID-19 cytokinemia is distinct from
that of other types of pneumonia, leading to organ failure and ICU need.
Neutrophils undergo immunometabolic reprogramming in severe COVID-19 illness.
Cytokine ratios may predict outcomes in this population.
Measurements and Main Results: IL-1β, IL-6, IL-8, and sTNFR1 were all increased in
patients with COVID-19. COVIDICU patients could be clearly differentiated
from COVIDstable patients, and demonstrated higher levels of
IL-1β, IL-6, and sTNFR1 but lower IL-10 than CAPICU patients. COVID-19 neutrophils displayed
altered immunometabolism, with increased cytosolic PKM2 (pyruvate kinase M2),
phosphorylated PKM2, HIF-1α (hypoxia-inducible factor-1α), and lactate. The production
and sialylation of AAT increased in COVID-19, but this antiinflammatory
response was overwhelmed in severe illness, with the IL-6:AAT ratio markedly
higher in patients requiring ICU admission (P < 0.0001). In critically unwell patients
with COVID-19, increases in IL-6:AAT predicted prolonged ICU stay and
mortality, whereas improvement in IL-6:AAT was associated with clinical
resolution (P
Conclusions: The COVID-19 cytokinemia is distinct from
that of other types of pneumonia, leading to organ failure and ICU need.
Neutrophils undergo immunometabolic reprogramming in severe COVID-19 illness.
Cytokine ratios may predict outcomes in this population.</p