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Search Results: 1 - 10 of 292345 matches for " Catherine D O'Connell "
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Multiple strand displacement amplification of mitochondrial DNA from clinical samples
Samantha Maragh, John P Jakupciak, Paul D Wagner, William N Rom, David Sidransky, Sudhir Srivastava, Catherine D O'Connell
BMC Medical Genetics , 2008, DOI: 10.1186/1471-2350-9-7
Abstract: DNA was isolated from clinical samples and sent to NIST. Samples were amplified by PCR and those with no visible amplification were re-amplified using the Multiple Displacement Amplificaiton technique of whole genome amplification. All samples were analyzed by mitochip for mitochondrial DNA sequence to compare sequence concordance of the WGA samples with respect to native DNA. Real-Time PCR analysis was conducted to determine the level of WGA amplification for both nuclear and mtDNA.In total, 19 samples were compared and the concordance rate between WGA and native mtDNA sequences was 99.995%. All of the cancer associated mutations in the native mtDNA were detected in the WGA amplified material and heteroplasmies in the native mtDNA were detected with high fidelity in the WGA material. In addition to the native mtDNA sequence present in the sample, 13 new heteroplasmies were detected in the WGA material.Genetic screening of mtDNA amplified by WGA is applicable for the detection of cancer associated mutations. Our results show the feasibility of this method for: 1) increasing the amount of DNA available for analysis, 2) recovering the identical mtDNA sequence, 3) accurately detecting mtDNA point mutations associated with cancer.It is often the case that an insufficient quantity of DNA can be isolated from clinical specimens and controls for full genome analysis. The quantity of DNA is particularly limited in patient tumor specimens, most notably in early tumors with limited mass and therefore, insufficient DNA may be available to perform the multiple analyses required for full genome screening [1-4]. Whole genome amplification (WGA) methods have been developed to solve the problem of insufficient quantities of DNA [5,6]. Using these technologies, investigators have been successful in applying genome scanning technologies to patient cohort samples collected years ago that are not recoverable by other means [7]. WGA is useful for amplification of DNA from stored histolo
In Silico Assigned Resistance Genes Confer Bifidobacterium with Partial Resistance to Aminoglycosides but Not to Β-Lactams
Fiona Fouhy, Mary OConnell Motherway, Gerald F. Fitzgerald, R. Paul Ross, Catherine Stanton, Douwe van Sinderen, Paul D. Cotter
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0082653
Abstract: Bifidobacteria have received significant attention due to their contribution to human gut health and the use of specific strains as probiotics. It is thus not surprising that there has also been significant interest with respect to their antibiotic resistance profile. Numerous culture-based studies have demonstrated that bifidobacteria are resistant to the majority of aminoglycosides, but are sensitive to β-lactams. However, limited research exists with respect to the genetic basis for the resistance of bifidobacteria to aminoglycosides. Here we performed an in-depth in silico analysis of putative Bifidobacterium-encoded aminoglycoside resistance proteins and β-lactamases and assess the contribution of these proteins to antibiotic resistance. The in silico-based screen detected putative aminoglycoside and β-lactam resistance proteins across the Bifidobacterium genus. Laboratory-based investigations of a number of representative bifidobacteria strains confirmed that despite containing putative β-lactamases, these strains were sensitive to β-lactams. In contrast, all strains were resistant to the aminoglycosides tested. To assess the contribution of genes encoding putative aminoglycoside resistance proteins in Bifidobacterium sp. two genes, namely Bbr_0651 and Bbr_1586, were targeted for insertional inactivation in B. breve UCC2003. As compared to the wild-type, the UCC2003 insertion mutant strains exhibited decreased resistance to gentamycin, kanamycin and streptomycin. This study highlights the associated risks of relying on the in silico assignment of gene function. Although several putative β-lactam resistance proteins are located in bifidobacteria, their presence does not coincide with resistance to these antibiotics. In contrast however, this approach has resulted in the identification of two loci that contribute to the aminoglycoside resistance of B. breve UCC2003 and, potentially, many other bifidobacteria.
Application of a Novel Tool for Diagnosing Bile Acid Diarrhoea
James A. Covington,Eric W. Westenbrink,Nathalie Ouaret,Ruth Harbord,Catherine Bailey,Nicola O'Connell,James Cullis,Nigel Williams,Chuka U. Nwokolo,Karna D. Bardhan,Ramesh P. Arasaradnam
Sensors , 2013, DOI: 10.3390/s130911899
Abstract: Bile acid diarrhoea (BAD) is a common disease that requires expensive imaging to diagnose. We have tested the efficacy of a new method to identify BAD, based on the detection of differences in volatile organic compounds (VOC) in urine headspace of BAD vs. ulcerative colitis and healthy controls. A total of 110 patients were recruited; 23 with BAD, 42 with ulcerative colitis (UC) and 45 controls. Patients with BAD also received standard imaging (Se75HCAT) for confirmation. Urine samples were collected and the headspace analysed using an AlphaMOS Fox 4000 electronic nose in combination with an Owlstone Lonestar Field Asymmetric Ion Mobility Spectrometer (FAIMS). A subset was also tested by gas chromatography, mass spectrometry (GCMS). Linear Discriminant Analysis (LDA) was used to explore both the electronic nose and FAIMS data. LDA showed statistical differences between the groups, with reclassification success rates (using an n-1 approach) at typically 83%. GCMS experiments confirmed these results and showed that patients with BAD had two chemical compounds, 2-propanol and acetamide, that were either not present or were in much reduced quantities in the ulcerative colitis and control samples. We believe that this work may lead to a new tool to diagnose BAD, which is cheaper, quicker and easier that current methods.
Performance of mitochondrial DNA mutations detecting early stage cancer
John P Jakupciak, Samantha Maragh, Maura E Markowitz, Alissa K Greenberg, Mohammad O Hoque, Anirban Maitra, Peter E Barker, Paul D Wagner, William N Rom, Sudhir Srivastava, David Sidransky, Catherine D O'Connell
BMC Cancer , 2008, DOI: 10.1186/1471-2407-8-285
Abstract: We determined the mtDNA mutation load in the entire mitochondrial genome of 26 individuals with different early stage cancers (lung, bladder, kidney) and 12 heavy smokers without cancer. MtDNA was sequenced from three matched specimens (blood, tumor and body fluid) from each cancer patient and two matched specimens (blood and sputum) from smokers without cancer. The inherited wildtype sequence in the blood was compared to the sequences present in the tumor and body fluid, detected using the Affymetrix Genechip? Human Mitochondrial Resequencing Array 1.0 and supplemented by capillary sequencing for noncoding region.Using this high-throughput method, 75% of the tumors were found to contain mtDNA mutations, higher than in our previous studies, and 36% of the body fluids from these cancer patients contained mtDNA mutations. Most of the mutations detected were heteroplasmic. A statistically significantly higher heteroplasmy rate occurred in tumor specimens when compared to both body fluid of cancer patients and sputum of controls, and in patient blood compared to blood of controls. Only 2 of the 12 sputum specimens from heavy smokers without cancer (17%) contained mtDNA mutations. Although patient mutations were spread throughout the mtDNA genome in the lung, bladder and kidney series, a statistically significant elevation of tRNA and ND complex mutations was detected in tumors.Our findings indicate comprehensive mtDNA resequencing can be a high-throughput tool for detecting mutations in clinical samples with potential applications for cancer detection, but it is unclear the biological relevance of these detected mitochondrial mutations. Whether the detection of tumor-specific mtDNA mutations in body fluidsy this method will be useful for diagnosis and monitoring applications requires further investigation.The mitochondrial genome is well characterized and is composed of 16,568 base pairs, harboring 37 densely packed genes [1]. The mitochondrial genome has an accelerated
Analgesic Regimen and Readmission Following Tonsillectomy  [PDF]
Lyudmila Kishikova, Matthew D. Smith, Jason C. Fleming, Michael OConnell
International Journal of Otolaryngology and Head & Neck Surgery (IJOHNS) , 2013, DOI: 10.4236/ijohns.2013.24026
Abstract:

Objective: To define the analgesic regimen given following tonsillectomy in a large ENT department and correlate this with readmission for secondary complications. Methods: We performed a retrospective case note review of patients undergoing tonsillectomy within a six month period. Demographic information and relevant case information was collected including operative details, discharge medication and readmission details. Results: 125 patients underwent tonsillectomy during the period. 17 different post-operative analgesic regimens were identified with the most common being a paracetamol and ibuprofen combination (26.4%). 13 patients (10.4%) were readmitted following discharge from hospital post-operatively, four (3.2%) for issues related to pain. There was no correlation between analgesic regimens and readmission. Conclusion: No apparent link between readmission and analgesic regimen was identified. The vast variation of analgesic regimens used has prompted development of a formal step-based analgesic protocol.

Enhanced Virulence of Chlamydia muridarum Respiratory Infections in the Absence of TLR2 Activation
Xianbao He,Anjali Nair,Samrawit Mekasha,Joseph Alroy,Catherine M. O'Connell,Robin R. Ingalls
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0020846
Abstract: Chlamydia trachomatis is a common sexually transmitted pathogen and is associated with infant pneumonia. Data from the female mouse model of genital tract chlamydia infection suggests a requirement for TLR2-dependent signaling in the induction of inflammation and oviduct pathology. We hypothesized that the role of TLR2 in moderating mucosal inflammation is site specific. In order to investigate this, we infected mice via the intranasal route with C. muridarum and observed that in the absence of TLR2 activation, mice had more severe disease, higher lung cytokine levels, and an exaggerated influx of neutrophils and T-cells into the lungs. This could not be explained by impaired bacterial clearance as TLR2-deficient mice cleared the infection similar to controls. These data suggest that TLR2 has an anti-inflammatory function in the lung during Chlamydia infection, and that the role of TLR2 in mucosal inflammation varies at different mucosal surfaces.
The ACTwatch project: methods to describe anti-malarial markets in seven countries
Tanya Shewchuk, Kathryn A O'Connell, Catherine Goodman, Kara Hanson, Steven Chapman, Desmond Chavasse
Malaria Journal , 2011, DOI: 10.1186/1475-2875-10-325
Abstract: The project is being conducted in seven malaria-endemic countries: Benin, Cambodia, the Democratic Republic of Congo, Madagascar, Nigeria, Uganda and Zambia from 2008 to 2012.ACTwatch measures which anti-malarials are available, where they are available and at what price and who they are used by. These indicators are measured over time and across countries through three study components: outlet surveys, supply chain studies and household surveys. Nationally representative outlet surveys examine the market share of different anti-malarials passing through public facilities and private retail outlets. Supply chain research provides a picture of the supply chain serving drug outlets, and measures mark-ups at each supply chain level. On the demand side, nationally representative household surveys capture treatment seeking patterns and use of anti-malarial drugs, as well as respondent knowledge of anti-malarials.The research project provides findings on both the demand and supply side determinants of anti-malarial access. There are four key features of ACTwatch. First is the overlap of the three study components where nationally representative data are collected over similar periods, using a common sampling approach. A second feature is the number and diversity of countries that are studied which allows for cross-country comparisons. Another distinguishing feature is its ability to measure trends over time. Finally, the project aims to disseminate findings widely for decision-making.ACTwatch is a unique multi-country research project that threads together anti-malarial supply and consumer behaviour to provide an evidence base to policy makers that can help determine where interventions may positively impact access to and use of quality-assured ACT and RDTs. Because of its ability to detect change over time, it is well suited to monitor the effects of policy or intervention developments in a country.Artemisinin-based combination therapy (ACT) is recommended by the WHO as
Chemical Abundances of Red Giant Stars in the Globular Cluster M107 (NGC 6171)
Julia E. O'Connell,Christian I. Johnson,Catherine A. Pilachowski,Geoffrey Burks
Physics , 2011, DOI: 10.1086/662138
Abstract: We present chemical abundances of Al and several Fe-Peak and neutron-capture elements for 13 red giant branch stars in the Galactic globular cluster NGC 6171 (M107). The abundances were determined using equivalent width and spectrum synthesis analyses of moderate resolution (R~15,000), moderate signal-to-noise ratio (~80) spectra obtained with the WIYN telescope and Hydra multifiber spectrograph. A comparison between photometric and spectroscopic effective temperature estimates seems to indicate a reddening value of E(B-V)=0.46 may be more appropriate for this cluster than the more commonly used value of E(B-V)=0.33. Similarly, we found that a distance modulus of (m-M)V~13.7 provided reasonable surface gravity estimates for the stars in our sample. Our spectroscopic analysis finds M107 to be moderately metal-poor with <[Fe/H]>= -0.93 and also exhibits a small star-to-star metallicity dispersion (sigma=0.04). These results are consistent with previous photometric and spectroscopic studies. Aluminum appears to be moderately enhanced in all program stars (<[Al/Fe]>=+0.39, sigma=0.11). The relatively small star-to-star scatter in [Al/Fe] differs from the trend found in more metal-poor globular clusters, and is more similar to what is found in clusters with [Fe/H] greater than about -1. The cluster also appears to be moderately r-process enriched with <[Eu/La]>=+0.32 (sigma=0.17).
The Value of Positive Pressure Ventilations for Clients in Acute Respiratory Distress as a Result of Cardiac and Pulmonary Issues  [PDF]
Patrick OConnell
Open Journal of Respiratory Diseases (OJRD) , 2015, DOI: 10.4236/ojrd.2015.52005
Abstract: Objective: Research was conducted to examine benefits to using non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) early in the treatment of respiratory distress caused by pulmonary edema, chronic obstructive pulmonary disease (COPD) and asthma. Limitations to successful NIV and CPAP therapy were evaluated to determine how prolonged initiation of treatment may lead to hypoxemia (decreased oxygen in the blood) and hypercapnia (increased carbon dioxide in the blood) resulting in poor outcomes. Method: Reviews of literature from nursing and allied health data bases (CINAHL and ProQuest) with terms pulmonary edema, positive pressure device and non-invasive ventilation from 2010 to 2014 were used. Studies were conducted in the hospital and prehospital settings. Results: The literature search located 7 articles from CINAHL and 25 articles from ProQuest. A total of 6 of these articles were analyzed. Additional sources of data were obtained from Ignatavicius and Workman (2013) Medical-Surgical Nursing Patient-Centered Collaborative Care 7th edition and American Journal of Nursing (02/2013) Volume 113: 2. Conclusion: All of the articles concluded that early initiation of continuous positive airway pressure ventilations in the short-term was beneficial; however, late initiation of therapy required additional interventions. The studies indicated that early use of positive airway pressure in acute respiratory distress improved breath rate, heart rate and blood pressure. The use of positive airway pressure for respiratory distress may decrease the need for endotracheal intubation.
Conditional survival of cancer patients: an Australian perspective
Yu Xue,Baade Peter D,OConnell Dianne L
BMC Cancer , 2012, DOI: 10.1186/1471-2407-12-460
Abstract: Background Estimated conditional survival for cancer patients diagnosed at different ages and disease stage provides important information for cancer patients and clinicians in planning follow-up, surveillance and ongoing management. Methods Using population-based cancer registry data for New South Wales Australia, we estimated conditional 5-year relative survival for 11 major cancers diagnosed 1972–2006 by time since diagnosis and age and stage at diagnosis. Results 193,182 cases were included, with the most common cancers being prostate (39,851), female breast (36,585) and colorectal (35,455). Five-year relative survival tended to increase with increasing years already survived and improvement was greatest for cancers with poor prognosis at diagnosis (lung or pancreas) and for those with advanced stage or older age at diagnosis. After surviving 10 years, conditional 5-year survival was over 95% for 6 localised, 6 regional, 3 distant and 3 unknown stage cancers. For the remaining patient groups, conditional 5-year survival ranged from 74% (for distant stage bladder cancer) to 94% (for 4 cancers at different stages), indicating that they continue to have excess mortality 10–15 years after diagnosis. Conclusion These data provide important information for cancer patients, based on age and stage at diagnosis, as they continue on their cancer journey. This information may also be used by clinicians as a tool to make more evidence-based decisions regarding follow-up, surveillance, or ongoing management according to patients' changing survival expectations over time.
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