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1.  OptiVol fluid index predicts acute decompensation of heart failure with a high rate of unexplained events 
Background
Intrathoracic impedance monitoring has emerged as a promising new technique for the detection of impending heart failure (HF). Although false positive episodes have been reported in case reports and clinical trials, the efficacy and false positive rate in real-world practice remain unclear.
Objective
The aim of this study is to investigate the utility and reliability of the OptiVol alert feature in clinical practice.
Methods
We continuously recruited patients who underwent implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with defibrillator (CRT-D) implantation with feature of intrathoracic impedance monitoring system in our center from Sep. 2010 to Oct. 2012. Regular in-office follow-up were required of all patients and the following information was collected at each visit: medical history, device interrogation, N-terminal pro-brain natriuretic peptide (NT-proBNP) measurement and an echocardiogram. Worsening HF was defined as hospitalization or the presentation of signs or symptoms of HF.
Results
Forty three patients (male: 76.7%, mean age: 57 ± 15 years, left ventricular ejection fraction (LVEF): 33% ± 14%) were included in this observational study. Fifty four alert events and 14 adjudicated worsening HF were detected within 288 ±163 days follow-up. Eleven (20.4%) alert episodes were associated with acute cardiac decompensation in 9 patients with a positive predictive value of 78.6%. Forty three audible alerts showed no connection to worsening HF. The unexplained alerts rate was 79.6% and 1.27 per person-year. Thirty seven alarm alerts were detected in patients with EF < 45%, among which 9 accompanied with HF, 17 alerts detected in patients with LVEF ≥ 45% and 2 associated with HF. There was no significant difference between the two groups (9/37 vs. 2/17; P = 0.47).
Conclusions
Patients with normal or nearly normal left ventricular systolic function also exhibited considerable alert events. The OptiVol fluid index predicted worsening cardiac events with a high unexplained detection rate, and any alert must therefore be analyzed with great caution. Efforts to improve the specificity of this monitoring system represent a significant aspect of future studies.
doi:10.3969/j.issn.1671-5411.2013.03.012
PMCID: PMC3796699  PMID: 24133513
Heart failure; Intrathoracic impedance measurement; OptiVol fluid index; Left ventricular ejection fraction
2.  Fluid status monitoring with a wireless network to reduce cardiovascular-related hospitalizations and mortality in heart failure: rationale and design of the OptiLink HF Study (Optimization of Heart Failure Management using OptiVol Fluid Status Monitoring and CareLink) 
European Journal of Heart Failure  2011;13(7):796-804.
Aims
The Optimization of Heart Failure Management using OptiVol Fluid Status Monitoring and CareLink (OptiLink HF) study is designed to investigate whether OptiVol fluid status monitoring with an automatically generated wireless CareAlert notification via the CareLink Network can reduce all-cause death and cardiovascular hospitalizations in an HF population, compared with standard clinical assessment.
Methods
Patients with newly implanted or replacement cardioverter-defibrillator devices with or without cardiac resynchronization therapy, who have chronic HF in New York Heart Association class II or III and a left ventricular ejection fraction ≤35% will be eligible to participate. Following device implantation, patients are randomized to either OptiVol fluid status monitoring through CareAlert notification or regular care (OptiLink ‘on' vs. ‘off'). The primary endpoint is a composite of all-cause death or cardiovascular hospitalization. It is estimated that 1000 patients will be required to demonstrate superiority of the intervention group to reduce the primary outcome by 30% with 80% power.
Conclusion
The OptiLink HF study is designed to investigate whether early detection of congestion reduces mortality and cardiovascular hospitalization in patients with chronic HF. The study is expected to close recruitment in September 2012 and to report first results in May 2014.
ClinicalTrials.gov Identifier: NCT00769457
doi:10.1093/eurjhf/hfr045
PMCID: PMC3125124  PMID: 21555324
Chronic heart failure; Disease management; Telemedicine; Cardiac resynchronization therapy; Implantable defibrillator; Bioimpedance
3.  Radiation management and credentialing of fluoroscopy users 
Pediatric Radiology  2006;36(Suppl 2):182-184.
During the last 15 years, developments in X-ray technologies have substantially improved the ability of practitioners to treat patients using fluoroscopically guided interventional techniques. Many of these procedures require a greater use of fluoroscopy and more recording of images. This increases the potential for radiation-induced dermatitis and epilation, as well as severe radiation-induced burns to patients. Many fluoroscope operators are untrained in radiation management and do not realize that these procedures increase the risk of radiation injury and radiation-induced cancer in personnel as well as patients. The hands of long-time fluoroscope operators in some cases exhibit radiation damage—especially when sound radiation protection practices have not been followed. In response, the Center for Devices and Radiological Health of the United States Food and Drug Administration has issued an Advisory calling for proper training of operators. Hospitals and administrators need to support and enforce the need for this training by requiring documentation of credentials in radiation management as a prerequisite for obtaining fluoroscopy privileges. A concerted effort on the part of professional medical organizations and regulatory agencies will be required to train fluoroscopy users to prevent physicians from unwittingly imparting serious radiation injuries to their patients.
doi:10.1007/s00247-006-0209-z
PMCID: PMC2663635  PMID: 16862411
Credentialing fluoroscopist; Fluoroscopist radiation dose
4.  Clinicians’ justification of imaging: do radiation issues play a role? 
Insights into Imaging  2010;1(3):193-200.
Objective
To explore clinicians’ knowledge and consideration of radiation, in relation to their referral practice and use of referral guidelines for imaging.
Methods
A questionnaire was handed out to 213 clinicians in Norway; all responded: 77 general practitioners, 71 hospital physicians and 65 non-physicians (55 manual physiotherapists, 10 chiropractors). Questions concerned weighting of radiation dose, guideline use, referrals unlikely to affect treatment, doses from imaging procedures, ranking of imaging as radiation source, and deterministic and stochastic effects. For radiation knowledge, a total score was aggregated.
Results
The mean radiation knowledge score was 30.4/71. Most respondents underestimated doses from high-dose imaging, e.g., barium enema (94.7%), chest CT (57.7%) and abdominal CT (52.7%). Limited radiation knowledge was not compensated by using guidelines. Only 20% of physicians and 72% of non-physicians used referral guidelines. Non-physicians weighted radiation dose as being more important than physicians when referring; they also reported fewer referrals as being unlikely to affect treatment. Such referrals and not using guidelines were related to lower weighting of radiation dose but not to radiation knowledge.
Conclusion
Limited radiation knowledge and guideline use indicate suboptimal justification of referrals. When justifying imaging, weighting of radiation dose may play a larger role than detailed radiation knowledge.
doi:10.1007/s13244-010-0029-4
PMCID: PMC3259314  PMID: 22347915
Diagnostic imaging; Referral guidelines; Radiation dosage; Questionnaires; Radiation protection
5.  Clinicians’ justification of imaging: do radiation issues play a role? 
Insights into Imaging  2010;1(3):193-200.
Objective
To explore clinicians’ knowledge and consideration of radiation, in relation to their referral practice and use of referral guidelines for imaging.
Methods
A questionnaire was handed out to 213 clinicians in Norway; all responded: 77 general practitioners, 71 hospital physicians and 65 non-physicians (55 manual physiotherapists, 10 chiropractors). Questions concerned weighting of radiation dose, guideline use, referrals unlikely to affect treatment, doses from imaging procedures, ranking of imaging as radiation source, and deterministic and stochastic effects. For radiation knowledge, a total score was aggregated.
Results
The mean radiation knowledge score was 30.4/71. Most respondents underestimated doses from high-dose imaging, e.g., barium enema (94.7%), chest CT (57.7%) and abdominal CT (52.7%). Limited radiation knowledge was not compensated by using guidelines. Only 20% of physicians and 72% of non-physicians used referral guidelines. Non-physicians weighted radiation dose as being more important than physicians when referring; they also reported fewer referrals as being unlikely to affect treatment. Such referrals and not using guidelines were related to lower weighting of radiation dose but not to radiation knowledge.
Conclusion
Limited radiation knowledge and guideline use indicate suboptimal justification of referrals. When justifying imaging, weighting of radiation dose may play a larger role than detailed radiation knowledge.
doi:10.1007/s13244-010-0029-4
PMCID: PMC3259314  PMID: 22347915
Diagnostic imaging; Referral guidelines; Radiation dosage; Questionnaires; Radiation protection
6.  The Outer Surface Lipoprotein VolA Mediates Utilization of Exogenous Lipids by Vibrio cholerae 
mBio  2013;4(3):e00305-13.
ABSTRACT
Previous work from our laboratory showed that the Gram-negative aquatic pathogen Vibrio cholerae can take up a much wider repertoire of fatty acids than other Gram-negative organisms. The current work elaborated on the ability of V. cholerae to exploit an even more diverse pool of lipid nutrients from its environment. We have demonstrated that the bacterium can use lysophosphatidylcholine as a metabolite for growth. Using a combination of thin-layer chromatography and mass spectrometry, we also showed that lysophosphatidylcholine-derived fatty acid moieties can be used for remodeling the V. cholerae membrane architecture. Furthermore, we have identified a lysophospholipase, VolA (Vibrio outer membrane lysophospholipase A), required for these activities. The enzyme is well conserved in Vibrio species, is coexpressed with the outer membrane fatty acid transporter FadL, is one of very few surface-exposed lipoprotein enzymes to be identified in Gram-negative bacteria and the first instance of a surface lipoprotein phospholipase. We propose a model whereby the bacterium efficiently couples the liberation of fatty acid from lysophosphatidylcholine to its subsequent metabolic uptake. An expanded ability to scavenge diverse environmental lipids at the bacterial surface increases overall bacterial fitness and promotes homeoviscous adaptation through membrane remodeling.
IMPORTANCE
Our understanding of how bacteria utilize environmental lipid sources has been limited to lipids such as fatty acids and cholesterol. This narrow scope may be attributed to both the intricate nature of lipid uptake mechanisms and the diversity of lipid substrates encountered within an ecological niche. By examining the ability of the pathogen Vibrio cholerae to utilize exogenous lipids, we uncovered a surface-exposed lipoprotein (VolA) that is required for processing the prevalent host lipid lysophosphatidylcholine. VolA functions as a lipase liberating a fatty acid from exogenous lysophospholipids. The freed fatty acid is then transported into the cell, serving as a carbon source, or shunted into phospholipid synthesis for membrane assembly. A limited number of surface-exposed lipoproteins have been found in Gram-negative organisms, and few have enzymatic function. This work highlights the ability of bacteria to exploit exogenous lipids for both maintenance of the membrane and carbon source acquisition.
doi:10.1128/mBio.00305-13
PMCID: PMC3656444  PMID: 23674613
7.  Erratum Vol. 4, No. 1 
In the article, "Emerging Infectious Diseases Brazil," by Hooman Momen, on page 3 the last sentence of the next-to-the-last paragraph should read, "The existing, generally passive epidemiologic surveillance system produces information that arrives too late to be effective; however, a number of measures, if implemented immediately, can mitigate the impact of any future epidemic: a containment laboratory (biosafety level 4) that can handle known and unknown microbes of high virulence; at least one infirmary, properly designed and fully equipped, to treat highly contagious and virulent diseases (the current lack of this facility poses a great danger to the population should an outbreak of such a disease occur); and a mobile multidisciplinary task force, including epidemiologists, microbiologists, entomologists, and clinicians, ready to investigate suspected disease outbreaks on short notice.
PMCID: PMC2640140  PMID: 9680508
8.  A transmissible avian neoplasm. (Sarcoma of the common fowl) by Peyton Rous, M.D., Experimental Medicine for Sept. 1, 1910, vol. 12, pp.696- 705 
In this paper is reported the first avian tumor that has proved transplantable to other individuals. It is a spindle-celled sarcoma of the hen, which thus far has been propagated into its fourth tumor generation. This was accomplished by the use of fowls of pure blood from the small, intimately related stock in which the growth occurred. Market-bought fowls of similar variety have shown themselves insusceptible, as have fowls of mixed breed, pigeons and guinea-pigs. The percentage of successful transplantations has been small, but in the individuals developing a tumor its growth has been fairly rapid. Young chickens are more susceptible than adults. The reinoculation of negative fowls has never resulted in a growth. Throughout, the sarcoma has remained true to type. It is infiltrative and destructive. Metastasis has been observed once (to the heart). Experiments to determine whether the growth may be transmitted by cell-fragments have not yet been made. Repeated bacteriological examinations have yielded negative results. In its general behavior, so far as tested, this avian tumor closely resembles the typical mammalian neoplasms that are transplantable.
PMCID: PMC2185676  PMID: 229185
13.  Assessment of radiation protection practices among radiographers in Lagos, Nigeria 
Background:
Use of ionising radiation in diagnostic radiography could lead to hazards such as somatic and genetic damages. Compliance to safe work and radiation protection practices could mitigate such risks. The aim of the study was to assess the knowledge and radiation protection practices among radiographers in Lagos, Nigeria.
Materials and Methods:
The study was a prospective cross sectional survey. Convenience sampling technique was used to select four x-ray diagnostic centres in four tertiary hospitals in Lagos metropolis. Data were analysed with Epi- info software, version 3.5.1.
Results:
Average score on assessment of knowledge was 73%. Most modern radiation protection instruments were lacking in all the centres studied. Application of shielding devices such as gonad shield for protection was neglected mostly in government hospitals. Most x-ray machines were quite old and evidence of quality assurance tests performed on such machines were lacking.
Conclusion:
Radiographers within Lagos metropolis showed an excellent knowledge of radiation protection within the study period. Adherence to radiation protection practices among radiographers in Lagos metropolis during the period studied was, however, poor. Radiographers in Lagos, Nigeria should embrace current trends in radiation protection and make more concerted efforts to apply their knowledge in protecting themselves and patients from harmful effects of ionising radiation.
doi:10.4103/0300-1652.126290
PMCID: PMC3948960  PMID: 24665152
Attitude; ionisation; protection; radiation; radiographers
14.  RADIATION: REGISTRATION OF SOURCES 
California Medicine  1960;92(3):198-200.
Registration of sources of ionizing radiation, including x-ray machines and radioactive material used in the healing professions, is required by legislation recently enacted in California. Registration will provide information concerning the type and location of sources of radiation, and will provide a basis for the evaluation of a need for additional radiation control and protection measures in the future.
As the medical uses of radiation procedures constitute a major portion of the total radiation exposure to the total population, it becomes increasingly important that physicians develop a reasonable and knowledgeable concept of not only the obvious benefits but also the actual and potential hazards of radiation as used in medicine. Practical and effective measures to minimize patient exposure, based on professional knowledge, competence and experience, with profession-wide participation and support, will insure the effective integration of the medical uses of radiation in the California Atomic Energy Development and Radiation Protection Program.
PMCID: PMC1578161  PMID: 13818568
16.  Comparative cost-efficiency of the EVOTECH endoscope cleaner and reprocessor versus manual cleaning plus automated endoscope reprocessing in a real-world Canadian hospital endoscopy setting 
BMC Gastroenterology  2011;11:105.
Background
Reprocessing of endoscopes generally requires labour-intensive manual cleaning followed by high-level disinfection in an automated endoscope reprocessor (AER). EVOTECH Endoscope Cleaner and Reprocessor (ECR) is approved for fully automated cleaning and disinfection whereas AERs require manual cleaning prior to the high-level disinfection procedure. The purpose of this economic evaluation was to determine the cost-efficiency of the ECR versus AER methods of endoscopy reprocessing in an actual practice setting.
Methods
A time and motion study was conducted at a Canadian hospital to collect data on the personnel resources and consumable supplies costs associated with the use of EVOTECH ECR versus manual cleaning followed by AER with Medivators DSD-201. Reprocessing of all endoscopes was observed and timed for both reprocessor types over three days. Laboratory staff members were interviewed regarding the consumption and cost of all disposable supplies and equipment. Exact Wilcoxon rank sum test was used for assessing differences in total cycle reprocessing time.
Results
Endoscope reprocessing was significantly shorter with the ECR than with manual cleaning followed by AER. The differences in median time were 12.46 minutes per colonoscope (p < 0.0001), 6.31 minutes per gastroscope (p < 0.0001), and 5.66 minutes per bronchoscope (p = 0.0040). Almost 2 hours of direct labour time was saved daily with the ECR. The total per cycle cost of consumables and labour for maintenance was slightly higher for EVOTECH ECR versus manual cleaning followed by AER ($8.91 versus $8.31, respectively). Including the cost of direct labour time consumed in reprocessing scopes, the per cycle and annual costs of using the EVOTECH ECR was less than the cost of manual cleaning followed by AER disinfection ($11.50 versus $11.88).
Conclusions
The EVOTECH ECR was more efficient and less costly to use for the reprocessing of endoscopes than manual cleaning followed by AER disinfection. Although the cost of consumable supplies required to reprocess endoscopes with EVOTECH ECR was slightly higher, the value of the labour time saved with EVOTECH ECR more than offset the additional consumables cost. The increased efficiency with EVOTECH ECR could lead to even further cost-savings by shifting endoscopy laboratory personnel responsibilities but further study is required.
doi:10.1186/1471-230X-11-105
PMCID: PMC3198958  PMID: 21967345
17.  Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF®), a new ultraviolet protection label for eyewear 
Ultraviolet (UV) radiation potentially damages the skin, the immune system, and structures of the eye. A useful UV sun protection for the skin has been established. Since a remarkable body of evidence shows an association between UV radiation and damage to structures of the eye, eye protection is important, but a reliable and practical tool to assess and compare the UV-protective properties of lenses has been lacking. Among the general lay public, misconceptions on eye-sun protection have been identified. For example, sun protection is mainly ascribed to sunglasses, but less so to clear lenses. Skin malignancies in the periorbital region are frequent, but usual topical skin protection does not include the lids. Recent research utilized exact dosimetry and demonstrated relevant differences in UV burden to the eye and skin at a given ambient irradiation. Chronic UV effects on the cornea and lens are cumulative, so effective UV protection of the eyes is important for all age groups and should be used systematically. Protection of children’s eyes is especially important, because UV transmittance is higher at a very young age, allowing higher levels of UV radiation to reach the crystalline lens and even the retina. Sunglasses as well as clear lenses (plano and prescription) effectively reduce transmittance of UV radiation. However, an important share of the UV burden to the eye is explained by back reflection of radiation from lenses to the eye. UV radiation incident from an angle of 135°–150° behind a lens wearer is reflected from the back side of lenses. The usual antireflective coatings considerably increase reflection of UV radiation. To provide reliable labeling of the protective potential of lenses, an eye-sun protection factor (E-SPF®) has been developed. It integrates UV transmission as well as UV reflectance of lenses. The E-SPF® compares well with established skin-sun protection factors and provides clear messages to eye health care providers and to lay consumers.
doi:10.2147/OPTH.S46189
PMCID: PMC3872277  PMID: 24379652
back reflection; transmission; irradiation; solar irradiance; aging; risk reduction; prevention
18.  Children, CT Scan and Radiation 
Children are more sensitive to radiation than adults. Computerized tomography (CT) consists of 25 % of all medical imaging. It was estimated that more than 2% of all carcinomas in the USA are due to CT scans. There is an ongoing focus on the reduction of CT scan radiation dose. Awareness about risk-benefits of CT has increased. Reduction of radiological exam is an important issue because the accumulation effects of radiation can be hazardous. In addition, proper protocol should be followed for diagnostic procedures of ionization radiation and computerized tomography. Effective radiation dose should range from 0.8 to 10.5 millisievert. The same protocol should be followed in different hospitals as well. Basic principles of radiation protection should be monitored. As much as possible, both technician and radiologist must be present during computerized tomography for children, and MRI and ultrasound should be replaced if possible.
PMCID: PMC3075516  PMID: 21566776
Computer tomography; Magnetic Resonance Imaging; Millisievert; Radiation; Prevention
19.  SWIMMY: Free Software for Teaching Neurophysiology of Neuronal Circuits 
To circumvent the many problems in teaching neurophysiology as a “wet lab,” we developed SWIMMY, a virtual fish that swims by moving its virtual tail by means of a virtual neural circuit. SWIMMY diminishes the need for expensive equipment, troubleshooting, and manual skills that require practice. Also, SWIMMY effectively replaces live preparations, which some students find objectionable.
Using SWIMMY, students (1) review the basics of neurophysiology, (2) identify the neurons in the circuit, (3) ascertain the neurons’ synaptic interconnections, (4) discover which cells generate the motor pattern of swimming, (5) discover how the rhythm is generated, and finally (6) use an animation that corresponds to the activity of the motoneurons to discover the behavioral effects produced by various lesions and explain them in terms of their neural underpinnings. SWIMMY is a genuine inquiry-based exercise producing data that requires individual thought and interpretation. It is neither a cookbook exercise nor a demonstration.
We have used SWIMMY for several terms with great success. SWIMMY solidifies students’ understanding of material learned in traditional lecture courses because they must apply the concepts. Student ratings of SWIMMY have been very positive, particularly ratings from students who have also been exposed to a “wet” neurophysiology lab.
Because SWIMMY requires only computers for implementation and makes minimal demands on instructional resources, it provides for a great deal of flexibility. Instructors could use SWIMMY as part of a traditional lab course, as a classroom exercise, in distance learning, or in blended instructional formats (internet with classroom). SWIMMY is now available for free online complete with student and instructor manuals at http://mdcune.psych.ucla.edu.
PMCID: PMC3592681  PMID: 23492869
Neurophysiology; simulation; Neuron; neural circuit; central pattern generator; neural oscillators; teaching neuroscience
20.  Radiation Protection in Canada 
The current recommendations of the International Commission on Radiological Protection have as a basic objective the limitation of the radiation dose to “that which involves a risk that is not unacceptable to the individual and to the population at large”. The problem is to decide what degree of risk is acceptable, in relation to the benefits of a practice that necessitates a radiation exposure. At the present time it is not possible to make more than very rough estimates of some of the risks of exposure to radiation, but such estimates can be usefully compared with some of the other risks that are tolerated by society. On the assumption that it would be possible to make quantitative assessments of both the benefits and the risks, the question is raised as to how and by whom an appropriate balance should be made.
PMCID: PMC1928157  PMID: 14275037

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