977 resultados para Preiction error methods
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An hemodialysis population in Central Brazil was screened by polymerase chain reaction (PCR) and serological methods to assess the prevalence of hepatitis C virus (HCV) infection and to investigate associated risk factors. All hemodialysis patients (n=428) were interviewed in eight dialysis units in Goiânia city. Blood samples were collected and serum samples screened for anti-HCV antibodies by an enzyme-linked immunosorbent assay (ELISA). Positive samples were retested for confirmation with a line immunoassay (LIA). All samples were also tested for HCV RNA by the PCR. An overall prevalence of 46.7% (CI 95%: 42-51.5) was found, ranging from 20.7% (CI 95%: 8.8-38.1) to 90.4% (CI 95%: 79.9-96.4) depending on the dialysis unit. Of the 428 patients, 185 were found to be seropositive by ELISA, and 167 were confirmed positive by LIA, resulting in an anti-HCV prevalence of 39%. A total of 131 patients were HCV RNA-positive. HCV viremia was present in 63.5% of the anti-HCV-positive patients and in 10.3% of the anti-HCV-negative patients. Univariate analysis of risk factors showed that the number of previous blood transfusions, transfusion of blood before mandatory screening for anti-HCV, length of time on hemodialysis, and treatment in multiple units were associated with HCV positivity. However, multivariate analysis revealed that blood transfusion before screening for anti-HCV and length of time on hemodialysis were significantly associated with HCV infection in this population. These data suggest that nosocomial transmission may play a role in the spread of HCV in the dialysis units studied. In addition to anti-HCV screening, HCV RNA detection is necessary for the diagnosis of HCV infection in hemodialysis patients.
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Report for the scientific sojourn carried out at the University of California at Berkeley, from September to December 2007. Environmental niche modelling (ENM) techniques are powerful tools to predict species potential distributions. In the last ten years, a plethora of novel methodological approaches and modelling techniques have been developed. During three months, I stayed at the University of California, Berkeley, working under the supervision of Dr. David R. Vieites. The aim of our work was to quantify the error committed by these techniques, but also to test how an increase in the sample size affects the resultant predictions. Using MaxEnt software we generated distribution predictive maps, from different sample sizes, of the Eurasian quail (Coturnix coturnix) in the Iberian Peninsula. The quail is a generalist species from a climatic point of view, but an habitat specialist. The resultant distribution maps were compared with the real distribution of the species. This distribution was obtained from recent bird atlases from Spain and Portugal. Results show that ENM techniques can have important errors when predicting the species distribution of generalist species. Moreover, an increase of sample size is not necessary related with a better performance of the models. We conclude that a deep knowledge of the species’ biology and the variables affecting their distribution is crucial for an optimal modelling. The lack of this knowledge can induce to wrong conclusions.
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Anaplastic lymphoma kinase (ALK) rearrangements represents a new driver oncogenic event in non-small cell lung cancer (NSCLC). ALK positive patients account for a 1-7% of NSCLC patients. The objective of this study is to know the prevalence and clinical characteristics of ALK positive patients in a cohort of NSCLC patients and to compare inmunohistochemistry with D5F3 monoclonal antibody with gold standard method fluorescence in situ hybridation
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RATIONALE AND OBJECTIVES: To determine optimum spatial resolution when imaging peripheral arteries with magnetic resonance angiography (MRA). MATERIALS AND METHODS: Eight vessel diameters ranging from 1.0 to 8.0 mm were simulated in a vascular phantom. A total of 40 three-dimensional flash MRA sequences were acquired with incremental variations of fields of view, matrix size, and slice thickness. The accurately known eight diameters were combined pairwise to generate 22 "exact" degrees of stenosis ranging from 42% to 87%. Then, the diameters were measured in the MRA images by three independent observers and with quantitative angiography (QA) software and used to compute the degrees of stenosis corresponding to the 22 "exact" ones. The accuracy and reproducibility of vessel diameter measurements and stenosis calculations were assessed for vessel size ranging from 6 to 8 mm (iliac artery), 4 to 5 mm (femoro-popliteal arteries), and 1 to 3 mm (infrapopliteal arteries). Maximum pixel dimension and slice thickness to obtain a mean error in stenosis evaluation of less than 10% were determined by linear regression analysis. RESULTS: Mean errors on stenosis quantification were 8.8% +/- 6.3% for 6- to 8-mm vessels, 15.5% +/- 8.2% for 4- to 5-mm vessels, and 18.9% +/- 7.5% for 1- to 3-mm vessels. Mean errors on stenosis calculation were 12.3% +/- 8.2% for observers and 11.4% +/- 15.1% for QA software (P = .0342). To evaluate stenosis with a mean error of less than 10%, maximum pixel surface, the pixel size in the phase direction, and the slice thickness should be less than 1.56 mm2, 1.34 mm, 1.70 mm, respectively (voxel size 2.65 mm3) for 6- to 8-mm vessels; 1.31 mm2, 1.10 mm, 1.34 mm (voxel size 1.76 mm3), for 4- to 5-mm vessels; and 1.17 mm2, 0.90 mm, 0.9 mm (voxel size 1.05 mm3) for 1- to 3-mm vessels. CONCLUSION: Higher spatial resolution than currently used should be selected for imaging peripheral vessels.
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Oscillations have been increasingly recognized as a core property of neural responses that contribute to spontaneous, induced, and evoked activities within and between individual neurons and neural ensembles. They are considered as a prominent mechanism for information processing within and communication between brain areas. More recently, it has been proposed that interactions between periodic components at different frequencies, known as cross-frequency couplings, may support the integration of neuronal oscillations at different temporal and spatial scales. The present study details methods based on an adaptive frequency tracking approach that improve the quantification and statistical analysis of oscillatory components and cross-frequency couplings. This approach allows for time-varying instantaneous frequency, which is particularly important when measuring phase interactions between components. We compared this adaptive approach to traditional band-pass filters in their measurement of phase-amplitude and phase-phase cross-frequency couplings. Evaluations were performed with synthetic signals and EEG data recorded from healthy humans performing an illusory contour discrimination task. First, the synthetic signals in conjunction with Monte Carlo simulations highlighted two desirable features of the proposed algorithm vs. classical filter-bank approaches: resilience to broad-band noise and oscillatory interference. Second, the analyses with real EEG signals revealed statistically more robust effects (i.e. improved sensitivity) when using an adaptive frequency tracking framework, particularly when identifying phase-amplitude couplings. This was further confirmed after generating surrogate signals from the real EEG data. Adaptive frequency tracking appears to improve the measurements of cross-frequency couplings through precise extraction of neuronal oscillations.
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This paper characterizes and evaluates the potential of three commercial CT iterative reconstruction methods (ASIR?, VEO? and iDose(4 ()?())) for dose reduction and image quality improvement. We measured CT number accuracy, standard deviation (SD), noise power spectrum (NPS) and modulation transfer function (MTF) metrics on Catphan phantom images while five human observers performed four-alternative forced-choice (4AFC) experiments to assess the detectability of low- and high-contrast objects embedded in two pediatric phantoms. Results show that 40% and 100% ASIR as well as iDose(4) levels 3 and 6 do not affect CT number and strongly decrease image noise with relative SD constant in a large range of dose. However, while ASIR produces a shift of the NPS curve apex, less change is observed with iDose(4) with respect to FBP methods. With second-generation iterative reconstruction VEO, physical metrics are even further improved: SD decreased to 70.4% at 0.5 mGy and spatial resolution improved to 37% (MTF(50%)). 4AFC experiments show that few improvements in detection task performance are obtained with ASIR and iDose(4), whereas VEO makes excellent detections possible even at an ultra-low-dose (0.3 mGy), leading to a potential dose reduction of a factor 3 to 7 (67%-86%). In spite of its longer reconstruction time and the fact that clinical studies are still required to complete these results, VEO clearly confirms the tremendous potential of iterative reconstructions for dose reduction in CT and appears to be an important tool for patient follow-up, especially for pediatric patients where cumulative lifetime dose still remains high.
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PURPOSE OF REVIEW: Invasive candidiasis is a severe infectious complication occurring mostly in onco-hematologic and surgical patients. Its conventional diagnosis is insensitive and often late, leading to a delayed treatment and a high mortality. The purpose of this article is to review recent contributions in the nonconventional diagnostic approaches of invasive candidiasis, both for the detection of the epidose and the characterization of the etiologic agent. RECENT FINDINGS: Antigen-based tests to detect invasive candidiasis comprise a specific test, mannan, as well as a nonspecific test, beta-D-glucan. Both have a moderate sensitivity and a high specificity, and cannot be recommended alone as a negative screening tool or a positive syndrome driven diagnostic tool. Molecular-based tests still have not reached the stage of rapid, easy to use, standardized tests ideally complementing blood culture at the time of blood sampling. New tests (fluorescence in-situ hybridization or mass spectrometry) significantly reduce the delay of identification of Candida at the species level in positive blood cultures, and should have a positive impact on earlier appropriate antifungal therapy and possibly on outcome. SUMMARY: Both antigen-based and molecular tests appear as promising new tools to complement and accelerate the conventional diagnosis of invasive candidiasis with an expected significant impact on earlier and more focused treatment and on prognosis.
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A total of 106 women with vaginitis in Nicaragua were studied. The positive rate for the identification of Candida species was 41% (44 positive cultures out of 106 women with vaginitis). The sensitivity of microscopic examination of wet mount with the potassium hydroxide (KOH) was 61% and 70% with Gram's stain when using the culture of vaginal fluid as gold standard for diagnosis of candidiasis. Among the 44 positives cultures, isolated species of yeast from vaginal swabs were C. albicans (59%), C. tropicalis (23%), C. glabrata (14%) and C. krusei (4%). This study reports the first characterization of 26 C. albicans stocks from Nicaragua by the random amplified polymorphic DNA method. The genetic analysis in this small C. albicans population showed the existence of linkage disequilibrium, which is consistent with the hypothesis that C. albicans undergoes a clonal propagation.
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Fraud is as old as Mankind. There are an enormous number of historical documents which show the interaction between truth and untruth; therefore it is not really surprising that the prevalence of publication discrepancies is increasing. More surprising is that new cases especially in the medical field generate such a huge astonishment. In financial mathematics a statistical tool for detection of fraud is known which uses the knowledge of Newcomb and Benford regarding the distribution of natural numbers. This distribution is not equal and lower numbers are more likely to be detected compared to higher ones. In this investigation all numbers contained in the blinded abstracts of the 2009 annual meeting of the Swiss Society of Anesthesia and Resuscitation (SGAR) were recorded and analyzed regarding the distribution. A manipulated abstract was also included in the investigation. The χ(2)-test was used to determine statistical differences between expected and observed counts of numbers. There was also a faked abstract integrated in the investigation. A p<0.05 was considered significant. The distribution of the 1,800 numbers in the 77 submitted abstracts followed Benford's law. The manipulated abstract was detected by statistical means (difference in expected versus observed p<0.05). Statistics cannot prove whether the content is true or not but can give some serious hints to look into the details in such conspicuous material. These are the first results of a test for the distribution of numbers presented in medical research.
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NICaN Regional Supportive & Palliative Care Network Friday 30th May 2008 Lecture Theatre, Fern House Antrim 2.00 pm - 5.00 pm Welcome, Introductions Stuart MacDonnell, Chair of the Supportive and Palliative Care network welcomed everyone to the meeting. This meeting had been rescheduled to accommodate the validation workshop for the regional palliative care model, which took place on Friday,18th April. Acknowledging the full agenda, several items were pulled forward to accommodate speakers SPC_0809_03 Modernisation and Reform of Supportive and Palliative care Mr MacDonnell welcomed Dr Sonja McIlfatrick and Dr Donna Fitzimons, members of the Phase 1 Project Team for the Modernisation and Reform of palliative care. Their presentation highlighted the journey taken by the Project Team since January 2008 - May 2008. Seeking to deliver the network vision, for any person with palliative care need, cancer or non - cancer, the project team incorporated several methodologies. The literature review identified best practice. An assessment of need including epidemiological data and review of service provision. Consultation reflected the engagement with patients, carers and professional forums, primary care and non-malignant focus groups. The breadth of consultation confirmed the evidence for the identified components of the model. These were validated at the April workshop. External review of the work was provided by Dr Phil Larkin (Galway Uni) Prof David Clark (End of Life Care Observatory, Lancaster University) and Mr Bob Neillans (Chair of the Mid Trent Palliative care network, which has been involved in the Delivering choice programme within Lincolnshire). The Guiding Principles of the model reinforced Patient and family centred care, enhanced community provision and supported by specialists. The components of the model are · Identification of patient with Palliative careened · Holistic Assessment · Integration of services · Coordination of care · End of Life Care and Bereavement Care The consultation process also highlighted the need for Increased Public and Professional Awareness. This was recognised as an encompassing component. Underpinning the model is the need for robust Education and common core values e.g. dignity, choice, advocacy, empowerment, partnership working. Stuart MacDonnell, who also chaired the steering group during the project, congratulated the Project Team for delivering the comprehensive document on schedule. The Report has been submitted to the NICaN Board and the DHSSPSNI. In addition, an outline for Phase 2 of this work has been submitted. Mr MacDonnell recognised that there is real opportunity for palliative care to benefit from the DHSSPSNI commitment to concrete developments. Phase 2 will progress the current high-level components of the model into quality services developments at a local level, demonstrating integration throughout. The methods propose continued engagement with the Delivering Choice Programme enabled through a Central and also Local Teams. The report and the Appendices care available on the NICaN website www.nican@n-i.nhs.uk SPC_0809_01 Chairman's Business · Update on the Cancer Service Framework, the document has been submitted and presented to the Departmental Programme Board. Next stages will include the review of costs and development of a implementation guidance It is hoped that the completed document should be available for public consultation in Autumn 2008. with a launch of the framework document and accompanying implementation guide in Spring 2009. Some funding has already been identified to advance key areas of work including, Advanced communication skills training, peer review and an appointment of a post to develop the cancerni.net, focusing on children and e-learning tools. · Children's and Adolescent Cancer network group , Liz Henderson is to convene a group to consider how this is to be taken forward. · NICaN appointments Recognition was given to the significant contribution made by Dr Gerard Daly during his position as NICaN Lead Clinician, particularly throughout the early establishment of the NICaN. Dr Dermott Hughes (Western Trust) has been appointed as the NICaN Medical Director. The Primary Care Director post has been advertised and it is hoped that the Director of Network will be advertised later in Summer. Endorsement of End of Life care paper. The Paper was presented and endorsed at the March 2008 NICaN Board meeting. Mr David Galloway (Director of Secondary Care) emphasised the need for this important work to be recognised within the regional model to ensure that it is reflected in future models of service delivery Congratulations were again echoed to the Chair of the End of Life Group for this work, Dr Glynis Henry, and the working group Other recognition Mr MacDonnell congratulated the significant achievements across the network. These include: · Dr Francis Robinson (Consultant Palliative Medicine, Western Trust) Awarded - Consultant of the year at the NI Health Care awards. · Mrs Evelyn Whittaker Hospice Nurse Specialist, NI Hospice, Joint Second Prize in the Development award within the International Journal of Palliative Nursing Awards, for her work in development of palliative care education in nursing homes. · Mr Ray Elder is the newly appointed Team Leader of Community Palliative care, SE Trust. · Mrs Bridget Denvir, who managed the establishment of one of the first community multiprofessional palliative care teams is moving to work with establishing integrated teams within the Belfast Trust. Bridget has been an active core member of the network and here contribution has been much appreciated. Mrs Sharon Barr will attend in future. SPC_0809_02 Minutes & matters Arising from Meeting, 13th December 2007 No amendments were made to the draft minutes from the December meeting. These will be posted on the NICaN website for future reference. Palliative Care Research Following consultation, the response to the business case for the All Ireland Institute was forwarded on 22 February 2008 to Prof David Clark. Prof Judith Hill informed the group that terms of tender are now being developed. Awareness raising across academic institutions continues to engage interest in potential partnerships. Atlantic Philantrophies have offered financial support to the venture and match funding is being sought from across jurisdictions. Previous discussions at Network meetings have endorsed the need to establish a work strand for research and development within palliative and end of life care. To identify the body of interested parties and explore the strengths and weaknesses of a collaborative model for research, a workshop, - Building collaboration for Palliative and End of life Care Research -will take place on 4 June 10am - 2pm.in the Comfort Hotel.Antrim, The workshop will be chaired by Prof David Clark, Director of the International Observatory on End of Life Care. Prof Shelia Payne, Help the Hospices Chair in Hospice Studies and co director of the Cancer Experiences Collaborative will present the Experiences and Results from Research Collaborative. Feedback from this event will be brought back to the next meeting in September. SPC_0809_04 Patient Information pathways - a pathway for advanced disease Ms Danny Sinclair, NICaN Regional Coordinator for Patient Information informed the network of how patient information pathways have been developed in line with the Cancer Services Collaborative. Emerging themes, with regard to information needs of patients with advanced disease, are being identified from the work undertaken across the tumour groups. It is important to identify all information needs to develop a generic pathway of information resources for advanced disease to be endorsed by the Supportive and Palliative care network. This could be used across the all tumour specific information pathways and across organisational boundaries. The resulting pathway could potentially be used for non- cancer condition. A group is to be established to take this work forward. The group will: · Develop a list of advanced disease information themes · .Identify when they become relevant for the patient or their carer · .Identify existing resources · .Develop resources where needed · .Participate or nominate when review is required Dr Sheila Kelly nominated Helen Hume (SETrust) Paula Kealey will also contribute to this work; a nomination from the Patient and Public Information Forum has also been identified. A date will be circulated across the network to engage further interest and establish group SPC_0809_08 Development of a Regional Syringe Driver Prescription Chart Ms Kathy Stephenson reported that the second consultation of the draft regional syringe driver prescription chart and the focus group discussions, Pilots of the chart are to be undertaken within Trust, Hospices and General Practices. SPC_0809_05 A framework for Generalist and Specialist Palliative and End of Life Care Competency Dr Kathleen Dunne, lead of the Education works strand, reported on the findings following consultation of the Education framework. The report was widely appreciated across the network and valued as a significant and timely document for the commissioning of generalist and specialist adult palliative care education. Mr MacDonnell congratulated Dr Dunne and the members of the education workstrand for developing the framework aligning its significance to the underpinning needs of the regional model Amendments will be made to the document and then forwarded to the NICaN Board for endorsement. A process of implementation will be explored and reported to the network group at the September meeting. Key target areas for generalist palliative care education were highlighted within care of the elderly and general medicine. . SPC_0809_06 Pallcareni.net-a website for people with palliative care needs Ms Danny Sinclair, reminded the group of the pending amalgamation of the CAPriCORN and NICaN website. The resulting new web address will be www. cancerni.net. Recurrent funding has been secured to ensure the development of the supportive and palliative care website.www.Pallcareni.net The new website will host good information for people with palliative care needs, regardless of diagnosis. It will be accessible via the cancerni.net portal or independently as the pallcareni portal. It will signpost people with palliative care needs to condition- specific websites. The website will also enable the communication needs of the NI Regional Supportive & Palliative Care Network. This is a very significant method of seeking to enable greater understanding of palliative care for public and professionals, as highlighted within the regional model. Currently the material from the CAPriCORN website is being migrated onto cancerni and /or pallcareni.net as appropriate. To enable the further development of this opportunity a steering group of interested individuals is to be established. Their role will be to: · Drive the development of the website so it meets the needs of public and professionals through the sourcing and development of additional content · Identify any support that is needed, e.g. technical support · Review the website as a whole as it grows (coordinating condition-specific developments) · Review the functions of the website to aid communication throughout the Supportive and Palliative care network The steering group representation should reflect the constituencies within the Supportive and Palliative Care network. Current expressions of interest have come from Heather Reid and Valerie Peacock. A date will be circulated across the network to engage further interest and establish group SPC_0809_07 Update of Guidelines workstrand Dr Pauline Wilkinson presented the current work within the guidelines workstrand. 1. Brief Holistic Assessment & Referral Criteria to Specialist Palliative Care The development of an Holistic assessment Tool will help to identify holistic need at generalist and specialist level. Recognition of complex need prompts appropriate referral to specialist palliative care. The regional referral form is compatible with the Minimum Data set. The final drafts of this work are to be circulated widely, inclusive of service framework groups, primary care, secondary care and the supportive and palliative care network. Consultation will take place during June and July. Piloting of the forms will also be undertaken. 2. Control of Pain in Cancer Patients The original guidelines where developed 2003 and are now ready for review. The Mapping exercise, undertaken in May 2007, highlighted that the Guidelines were poorly adopted. The group have reviewed the pending SIGN 2 guidelines for pain with regard to practice in Northern Ireland. These are highly evidence based and are due to be launched this Summer. Whilst an excellent resource their comprehensiveness limits their readability, this may result in poor compliance. The Guidelines group feel it is important to have accessible and user-friendly guidelines particularly for Generalists and Out of hours. There are examples of good work that has taken place across the province, but there is a need for regional consistency. Dr Wilkinson has contacted Dr Carolyn Harper (Deputy CMO) and GAIN with regard to enabling funding to progress this work. The Guidelines group hope to approach the NICaN Primary Care Group to work in collaboratively on this piece, based on the templates already available. The works should be available in both electronic and paper versions. 3. Care of the dying & Breaking bad news Dr Gail Johnston has now completed an Audit of the Care of the Dying Pathways within the EHSSB. Gail is also seeking to examine to what extent the Regional Guidelines for Breaking Bad News are being implemented in the EHSSB with a view to identifying the need for further training or organisational structures that would facilitate future uptake. 4. Advances in new Technology Syringe Drivers Dr Wilkinson reported on a presentation made to the guidelines group by Mr Jim Elliot, Principle Engineer, Cardiology & Ann McLean, and Macmillan Palliative Care Nurse RVH. There is increasing concern with regard to how devices meet the recommended safety standards and how to reduce error. New devices have 3 point checking, automatic detection of syringe, automatic flow rates, full range of alarms, battery status and data download to provide an event log. There are now 2 companies in UK who have devices that meet these safety criteria. The current Graseby syringe drivers, which have been on the market and used predominately within Northern Ireland over the past 27 years Most new devices are not compatible with the regionally available monoject syringe, however contractual changes will lead to the withdrawal of the monoject syringes in October 2008. The Guidelines group supports a regional approach to this matter. This was echoed in the Supportive and Palliative care network. An option appraisal, identifying costs, and training issues should be developed through the engagement with Trusts and DHSSPSNI. The issue of Patient safety should be raised with the DHSSPSNI. SPC_0809_09 Evaluation of Supportive and Palliative Care network Deferred to next meeting. . SPC_0809_10 Emerging Issues Mrs Anne Coyle, Bereavement Coordinator, Southern Trust, announced that the Regional Bereavement Strategy is soon to be released. Anne supported the close alignment between the content of the strategy and the work of the regional model and other workstrands within the Supportive and Palliative care network. Ms Eleanor Donaghy, Transplant Coordinator, briefly highlighted the issue of tissue donation. Each year Northern Ireland has a dearth of corneal donations. There is no upper age limit for donation and retrieval is not limited by a cancer diagnosis. Recipients do not require immunosuppressive and the transplant is lifelong. The National Blood Service provided coordination of this donation they may be contacted via 07659180773. It is hoped that Mrs Coyle and Ms Donaghy could provide more comprehensive presentations at a future meeting. Events · Irish Psycho- Oncology Group Seminar, Cork 6 June, Exploring the Struggle for meaning in Cancer · Integrated Care: Putting Research into Practice, 13June, Trinity College, Dublin · Macmillan online conference Friday 13 June 2008, 9am - 5pm · Delivering effective end of life care: developing partnership working 15 Oct 2008, 9.30 -4.15 pm London Network Meeting was closed at 5.00pm SPC_0607_ Dates of Future Meetings (please note the change of venue) 10th September 2008, 1.30 - 5pm venue to be decided15th January 2009, 1.30 - 5pm venue to be decided12th May 2009, 1.30 - 5pm venue to be decided Attendances Apologies Stuart MacDonnellLorna NevinSonja McIlfatrick Donna FitzsimonsKathleen DunnePauline WilkinsonKathy StephensonSheila KellyMarie Nugent,Anne CoyleFiona GilmourJudith HillLorna DicksonMargaret CarlinLoretta GribbenYvonne Duff Lesley NelsonLiz HendersonSue FosterCathy PayneGraeme PaynePatricia MageeGeraldine WeatherupPaula KealyCaroline McAfeeLinda WrayValerie PeacockAnn McCleanRay Elder Martin BradleyHelen HumeGillian RankinHeather MonteverdeJulie DoyleAlison PorterYvonne SmythLiz Atkinson,Glynis HenryMaeve HullyCaroline HughesAnn FinnBob BrownSharon BarrJulie DoyleJanis McCulla .
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Bacteria can survive on hospital textiles and surfaces, from which they can be disseminated, representing a source of health care-associated infections (HCAIs). Surfaces containing copper (Cu), which is known for its bactericidal properties, could be an efficient way to lower the burden of potential pathogens. The antimicrobial activity of Cu-sputtered polyester surfaces, obtained by direct-current magnetron sputtering (DCMS), against methicillin-resistant Staphylococcus aureus (MRSA) was tested. The Cu-polyester microstructure was characterized by high-resolution transmission electron microscopy to determine the microstructure of the Cu nanoparticles and by profilometry to assess the thickness of the layers. Sputtering at 300 mA for 160 s led to a Cu film thickness of 20 nm (100 Cu layers) containing 0.209% (wt/wt) polyester. The viability of MRSA strain ATCC 43300 on Cu-sputtered polyester was evaluated by four methods: (i) mechanical detachment, (ii) microcalorimetry, (iii) direct transfer onto plates, and (iv) stereomicroscopy. The low efficacy of mechanical detachment impeded bacterial viability estimations. Microcalorimetry provided only semiquantitative results. Direct transfer onto plates and stereomicroscopy seemed to be the most suitable methods to evaluate the bacterial inactivation potential of Cu-sputtered polyester surfaces, since they presented the least experimental bias. Cu-polyester samples sputtered for 160 s by DCMS were further tested against 10 clinical MRSA isolates and showed a high level of bactericidal activity, with a 4-log(10) reduction in the initial MRSA load (10(6) CFU) within 1 h. Cu-sputtered polyester surfaces might be of use to prevent the transmission of HCAI pathogens.
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A field survey on schistosomiais was carried out in 1998, in the municipality of Pedro de Toledo, a low endemic area in the state of São Paulo, Brazil. According to the parasitologic Kato-Katz method, the prevalence rate was 1.6%, with an infection intensity of 40.9 eggs per gram of stool. By the immunofluorescence test (IFT) for detection of IgG and IgM antibodies in the serum, IgG-IFT and IgM-IFT, respectively, prevalence indices of 33.2% and 33.5% were observed. To assess the impact of the schistosomiasis control program in the area, parasitologic and serologic data obtained in 1998, analyzed according to the age, sex, and residence zone, were compared to previous data obtained in a epidemiologic study carried out in 1980, when prevalence indices were of 22.8% and 55.5%, respectively by Kato-Katz and IgG-IFT. A significant fall of the prevalence was observed, indicating that the control measures were effective. Nonetheless, residual transmission was observed, demonstrating the need for a joint effort to include new approaches for better understanding the real situation and improving the control of the disease in low endemic areas.