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News Article | April 21, 2017
Site: www.eurekalert.org

Memphis, Tenn. - Which causes fewer eye infections - contact lens wear or LASIK surgery? While traditionally contacts were thought to be safer than a surgical procedure, an analysis by ophthalmologists from the Hamilton Eye Institute at the University of Tennessee Health Science Center indicates otherwise. A meta-data analysis comparing the incidence of microbial keratitis, an infection of the cornea caused by bacteria or a virus, for contact lens wearers versus post-LASIK (laser-assisted in situ keratomileusis) patients indicates that over time the infection rate for the contact lens wearers was higher than for those who had LASIK to correct their vision. An article on the findings was published in the Journal of Cataract & Refractive Surgery, a high-impact, peer-reviewed scientific journal. "Microbial keratitis is a relatively rare complication associated with contact lens use and LASIK postoperatively," the article said. The authors were Jordan Masters, MD; Mehmet Kocak, PhD; and Aaron Waite, MD. "The risk for microbial keratitis was similar between patients using contact lenses at one year, compared with LASIK. Over time, the risk for microbial keratitis was higher for contact lens use than for LASIK, specifically with extended-wear lenses." Literature in the PubMed database between December 2014 and July 2015 was analyzed. The results showed that after one year of daily soft-contact lens wear, there were fewer microbial keratitis cases than after LASIK, approximately two fewer cases per 10,000. If the surgery is assumed to have essentially a one-time risk for infection, after five years of extrapolation, contact lens wearers would show 11 more cases per 10,000 than those with surgery. "Most contact lens wearers use them for decades, which means they have a much higher risk of corneal infection compared to the risk with LASIK," said Dr. Waite, director of the Cornea, Cataract, and Refractive Surgery Program at the Hamilton Eye Institute and associate professor in the Department of Ophthalmology at UT Health Science Center. Microbial keratitis can be devastating, since it can lead to vision loss. It can also be expensive. Contact lens wear has been associated as a risk factor in the development of the condition. Factors, including hygiene, lens type, and history of use, contribute to the risk. According to the analysis, the approximately 38 million contact lens wearers in the United States accounted for an estimated 1 million clinical visits related to microbial keratitis at a cost of about $174.9 million in 2010. "We did this analysis to directly compare the rate for corneal infections between contact lens use and LASIK," Dr. Waite said. "Contact lenses carry a real risk of infection. In our experience with contact lens infections, some patients have lost vision and have needed a corneal transplant, or even lost the eye. There are cases where LASIK could have prevented this vision loss. LASIK does carry a rare risk of infection, however, it is a one-time risk compared to a continuous risk for infection in contact lens users. We wanted to compare the rates to get hard numbers." This is believed to be the first meta-analysis comparing the rates of microbial keratitis in contact lens wearers to those who have had LASIK surgery. "It is difficult to compare complications from contact lens use to LASIK, because the complication rate of both is so rare, but our analysis definitely shows that the infection rate is higher with contact lens use compared to LASIK," Dr. Waite said. More studies are needed to focus on other complications, such as vision loss and dry eye, to further explore the safety and risk of complications. As Tennessee's only public, statewide, academic health system, the mission of the University of Tennessee Health Science Center (UTHSC) is to bring the benefits of the health sciences to the achievement and maintenance of human health, with a focus on the citizens of Tennessee and the region, by pursuing an integrated program of education, research, clinical care, and public service. Offering a broad range of postgraduate and selected baccalaureate training opportunities, the main UTHSC campus is located in Memphis and includes six colleges: Dentistry, Graduate Health Sciences, Health Professions, Medicine, Nursing and Pharmacy. UTHSC also educates and trains cohorts of medicine, pharmacy and/or health professions students -- in addition to medical residents and fellows -- at its major sites in Knoxville, Chattanooga and Nashville. Founded in 1911, during its more than 100 years, UT Health Science Center has educated and trained more than 57,000 health care professionals in academic settings and health care facilities across the state. For more information, visit http://www. . Follow us on Facebook: facebook.com/uthsc, on Twitter: twitter.com/uthsc and on Instagram: instagram.com/uthsc.


Crill C.M.,University of Tennessee Health Science Center | Crill C.M.,Le Bonheur Childrens Medical Center | Hak E.B.,UTHSC | Robinson L.A.,Specialized Support Services
American Journal of Health-System Pharmacy | Year: 2010

Purpose. Microbial contamination associated with different methods of neonatal intravenous fat emulsion (IVFE) preparation and delivery was evaluated. Methods. Sterility testing was performed on IVFE dispensed via three different methods: (1) in the original container (n = 60), (2) repackaged into a syringe (n = 90), and (3) drawdown of the original container (n = 60). At the end of each infusion (24 hours for methods 1 and 3, 12 hours for method 2), a sample of the IVFE was with-drawn from the container using a sterile syringe in an International Organization for Standardization class 5 hood and sent to the hospital microbiology laboratory, where the samples were introduced into blood culture bottles and incubated for five days. Each sample was then subcultured on a blood agar plate with olive oil and left for an additional two days in a carbon dioxide incubator to assess for Malassezia furfur. Results. None of the samples from the original containers showed bacterial or fungal growth. Three of the samples from syringes had bacterial growth (two samples contained coagulase-negative staphylococcus and one contained both Klebsiella oxytoca and Citrobacter freundii), yielding a contamination rate of 3.3%. The number of contaminated samples did not significantly differ among the three preparation methods (p = 0.13). Conclusion. Repackaging IVFE into sterile syringes resulted in bacterial contamination and should be avoided in clinical practice. IVFE samples obtained using the drawdown procedure under sterile conditions for infusion over 24 hours revealed no microbial contamination. Copyright © 2010, American Society of Health-System Pharmacists, Inc. All rights reserved.


Graves D.T.,University of Pennsylvania | Oates T.,UTHSC
Journal of Oral Microbiology | Year: 2011

Both lesions of endodontic origin and periodontal diseases involve the host response to bacteria and the formation of osteolytic lesions. Important for both is the upregulation of inflammatory cytokines that initiate and sustain the inflammatory response. Also important are chemokines that induce recruitment of leukocyte subsets and bone-resorptive factors that are largely produced by recruited inflammatory cells. However, there are differences also. Lesions of endodontic origin pose a particular challenge since that bacteria persist in a protected reservoir that is not readily accessible to the immune defenses. Thus, experiments in which the host response is inhibited in endodontic lesions tend to aggravate the formation of osteolytic lesions. In contrast, bacteria that invade the periodontium appear to be less problematic so that blocking arms of the host response tend to reduce the disease process. Interestingly, both lesions of endodontic origin and periodontitis exhibit inflammation that appears to inhibit bone formation. In periodontitis, the spatial location of the inflammation is likely to be important so that a host response that is restricted to a subepithelial space is associated with gingivitis, while a host response closer to bone is linked to bone resorption and periodontitis. However, the persistence of inflammation is also thought to be important in periodontitis since inflammation present during coupled bone formation may limit the capacity to repair the resorbed bone. © 2011 Dana T. Graves et al.


News Article | February 16, 2017
Site: www.eurekalert.org

One of the main tools doctors use to detect diseases and injuries in cases ranging from multiple sclerosis to broken bones is magnetic resonance imaging (MRI). However, the results of an MRI scan take hours or days to interpret and analyze. This means that if a more detailed investigation is needed, or there is a problem with the scan, the patient needs to return for a follow-up. A new, supercomputing-powered, real-time analysis system may change that. Researchers from the Texas Advanced Computing Center (TACC), The University of Texas Health Science Center (UTHSC) and Philips Healthcare, have developed a new, automated platform capable of returning in-depth analyses of MRI scans in minutes, thereby minimizing patient callbacks, saving millions of dollars annually, and advancing precision medicine. The team presented a proof-of-concept demonstration of the platform at the International Conference on Biomedical and Health Informatics this week in Orlando, Florida. The platform they developed combines the imaging capabilities of the Philips MRI scanner with the processing power of the Stampede supercomputer -- one of the fastest in the world -- using the TACC-developed Agave API Platform infrastructure to facilitate communication, data transfer, and job control between the two. An API, or Application Program Interface, is a set of protocols and tools that specify how software components should interact. Agave manages the execution of the computing jobs and handles the flow of data from site to site. It has been used for a range of problems, from plant genomics to molecular simulations, and allows researchers to access cyberinfrastructure resources like Stampede via the web. "The Agave Platform brings the power of high-performance computing into the clinic," said William (Joe) Allen, a life science researcher for TACC and lead author on the paper. "This gives radiologists and other clinical staff the means to provide real-time quality control, precision medicine, and overall better care to the patient." For their demonstration project, staff at UTHSC performed MRI scans on a patient with a cartilage disorder to assess the state of the disease. Data from the MRI was passed through a proxy server to Stampede where it ran the GRAPE (GRAphical Pipelines Environment) analysis tool. Created by researchers at UTHSC, GRAPE characterizes the scanned tissue and returns pertinent information that can be used to do adaptive scanning - essentially telling a clinician to look more closely at a region of interest, thus accelerating the discovery of pathologies. The researchers demonstrated the system's effectiveness using a T1 mapping process, which converts raw data to useful imagery. The transformation involves computationally-intensive data analyses and is therefore a reasonable demonstration of a typical workflow for real-time, quantitative MRI. A full circuit, from MRI scan to supercomputer and back, took approximately five minutes to complete and was accomplished without any additional inputs or interventions. The system is designed to alert the scanner operator to redo a corrupted scan if the patient moves, or initiate additional scans as needed, while adding only minimal time to the overall scanning process. "We are very excited by this fruitful collaboration with TACC," said Refaat Gabr, an assistant professor of Diagnostic and Interventional Imaging at UTHSC and the lead researcher on the project. "By integrating the computational power of TACC, we plan to build a completely adaptive scan environment to study multiple sclerosis and other diseases." Ponnada Narayana, Gabr's co-principal investigator and the director of Magnetic Resonance Research at The University of Texas Medical School at Houston, elaborated. "Another potential of this technology is the extraction of quantitative, information-based texture analysis of MRI," he said. "There are a few thousand textures that can be quantified on MRI. These textures can be combined using appropriate mathematical models for radiomics. Combining radiomics with genetic profiles, referred to as radiogenomics, has the potential to predict outcomes in a number diseases, including cancer, and is a cornerstone of precision medicine." According to Allen, "science as a service" platforms like Agave will enable doctors to capture many kinds of biomedical data in real time and turn them into actionable insights. "Here, we demonstrated this is possible for MRI. But this same idea could be extended to virtually any medical device that gathers patient data," he said. "In a world of big health data and an almost limitless capacity to compute, there is little reason not to leverage high-performance computing resources in the clinic." The research is supported in part by National Science Foundation (NSF) award ACI-1450459, by the Clinical Translational Science Award (CTSA) Grant UL1-TR000371 from the National Institutes of Health (NIH) National Center for Advancing Translational Sciences, and by the Chair in Biomedical Engineering Endowment Fund. Stampede was generously funded by the NSF through award ACI-1134872.


Farook M.F.,UTHSC | DeCuypere M.,UTHSC | Hyland K.,Medical Neurogenetics | Takumi T.,Hiroshima University | And 2 more authors.
PLoS ONE | Year: 2012

Childhood neurodevelopmental disorders like Angelman syndrome and autism may be the result of underlying defects in neuronal plasticity and ongoing problems with synaptic signaling. Some of these defects may be due to abnormal monoamine levels in different regions of the brain. Ube3a, a gene that causes Angelman syndrome (AS) when maternally deleted and is associated with autism when maternally duplicated has recently been shown to regulate monoamine synthesis in the Drosophila brain. Therefore, we examined monoamine levels in striatum, ventral midbrain, frontal cerebral cortex, cerebellar cortex and hippocampus in Ube3a deficient and Ube3a duplication animals. We found that serotonin (5HT), a monoamine affected in autism, was elevated in the striatum and cortex of AS mice. Dopamine levels were almost uniformly elevated compared to control littermates in the striatum, midbrain and frontal cortex regardless of genotype in Ube3a deficient and Ube3a duplication animals. In the duplication 15q autism mouse model, paternal but not maternal duplication animals showed a decrease in 5HT levels when compared to their wild type littermates, in accordance with previously published data. However, maternal duplication animals show no significant changes in 5HT levels throughout the brain. These abnormal monoamine levels could be responsible for many of the behavioral abnormalities observed in both AS and autism, but further investigation is required to determine if any of these changes are purely dependent on Ube3a levels in the brain. © 2012 Farook et al.


Parker M.S.,University of Memphis | Park E.A.,UTHSC | Sallee F.R.,University of Cincinnati | Parker S.L.,UTHSC
Amino Acids | Year: 2011

For many G-protein coupling receptors (GPCRs), the upkeep of receptor dimers could depend on association with functional Gi α subunits. This is known for Y1, Y2 and Y4 neuropeptide Y receptors [presented in the companion paper (Estes et al., Amino Acids, doi: 10.1007/s00726-010-0642-z, 2010)]. Interactions with transducers use mainly intracellular domains of the receptors. Intracellular loops 1 and 2 in GPCRs are short and lack extensive helicity that could support transducer anchoring. Interaction with G-proteins is known to use the juxtamembrane Helix 8 in the fourth intracellular domain, for which we document a helix-stabilizing n/(n + 4) pattern of large hydrophobic sidechains. Another intracellular helix located in the C-terminal portion of the third intracellular loop does not display a strong stabilizing pattern, and is found in many studies to serve dynamically in association and activation of transducers and effectors. We show that these tracts share features across metazoan phyla not only in opsins and opsin-like receptors (including the Y receptors), but also in Taste-2 and Frizzled receptors. Similarities of these helices across GPCR groups could have both phylogenetic and functional roots. © 2010 Springer-Verlag.


Sabri F.,University of Memphis | Boughter Jr. J.D.,UTHSC | Gerth D.,UTHSC | Skalli O.,University of Memphis | And 3 more authors.
PLoS ONE | Year: 2012

Background: Aerogels are a versatile group of nanostructured/nanoporous materials with physical and chemical properties that can be adjusted to suit the application of interest. In terms of biomedical applications, aerogels are particularly suitable for implants such as membranes, tissue growth scaffolds, and nerve regeneration and guidance inserts. The mesoporous nature of aerogels can also be used for diffusion based release of drugs that are loaded during the drying stage of the material. From the variety of aerogels polyurea crosslinked silica aerogels have the most potential for future biomedical applications and are explored here. Methodology: This study assessed the short and long term biocompatibility of polyurea crosslinked silica aerogel implants in a Sprague-Dawley rat model. Implants were inserted at two different locations a) subcutaneously (SC), at the dorsum and b) intramuscularly (IM), between the gluteus maximus and biceps femoris of the left hind extremity. Nearby muscle and other internal organs were evaluated histologically for inflammation, tissue damage, fibrosis and movement (travel) of implant. Conclusion/Significance: In general polyurea crosslinked silica aerogel (PCSA) was well tolerated as a subcutaneous and an intramuscular implant in the Sprague-Dawley rat with a maximum incubation time of twenty months. In some cases a thin fibrous capsule surrounded the aerogel implant and was interpreted as a normal response to foreign material. No noticeable toxicity was found in the tissues surrounding the implants nor in distant organs. Comparison was made with control rats without any implants inserted, and animals with suture material present. No obvious or noticeable changes were sustained by the implants at either location. Careful necropsy and tissue histology showed age-related changes only. An effective sterilization technique for PCSA implants as well as staining and sectioning protocol has been established. These studies further support the notion that silica-based aerogels could be useful as biomaterials. © 2012 Sabri et al.


News Article | February 16, 2017
Site: phys.org

A new, supercomputing-powered, real-time analysis system may change that. Researchers from the Texas Advanced Computing Center (TACC), The University of Texas Health Science Center (UTHSC) and Philips Healthcare, have developed a new, automated platform capable of returning in-depth analyses of MRI scans in minutes, thereby minimizing patient callbacks, saving millions of dollars annually, and advancing precision medicine. The team presented a proof-of-concept demonstration of the platform at the International Conference on Biomedical and Health Informatics this week in Orlando, Florida. The platform they developed combines the imaging capabilities of the Philips MRI scanner with the processing power of the Stampede supercomputer—one of the fastest in the world—using the TACC-developed Agave API Platform infrastructure to facilitate communication, data transfer, and job control between the two. An API, or Application Program Interface, is a set of protocols and tools that specify how software components should interact. Agave manages the execution of the computing jobs and handles the flow of data from site to site. It has been used for a range of problems, from plant genomics to molecular simulations, and allows researchers to access cyberinfrastructure resources like Stampede via the web. "The Agave Platform brings the power of high-performance computing into the clinic," said William (Joe) Allen, a life science researcher for TACC and lead author on the paper. "This gives radiologists and other clinical staff the means to provide real-time quality control, precision medicine, and overall better care to the patient." For their demonstration project, staff at UTHSC performed MRI scans on a patient with a cartilage disorder to assess the state of the disease. Data from the MRI was passed through a proxy server to Stampede where it ran the GRAPE (GRAphical Pipelines Environment) analysis tool. Created by researchers at UTHSC, GRAPE characterizes the scanned tissue and returns pertinent information that can be used to do adaptive scanning - essentially telling a clinician to look more closely at a region of interest, thus accelerating the discovery of pathologies. The researchers demonstrated the system's effectiveness using a T1 mapping process, which converts raw data to useful imagery. The transformation involves computationally-intensive data analyses and is therefore a reasonable demonstration of a typical workflow for real-time, quantitative MRI. A full circuit, from MRI scan to supercomputer and back, took approximately five minutes to complete and was accomplished without any additional inputs or interventions. The system is designed to alert the scanner operator to redo a corrupted scan if the patient moves, or initiate additional scans as needed, while adding only minimal time to the overall scanning process. "We are very excited by this fruitful collaboration with TACC," said Refaat Gabr, an assistant professor of Diagnostic and Interventional Imaging at UTHSC and the lead researcher on the project. "By integrating the computational power of TACC, we plan to build a completely adaptive scan environment to study multiple sclerosis and other diseases." Ponnada Narayana, Gabr's co-principal investigator and the director of Magnetic Resonance Research at The University of Texas Medical School at Houston, elaborated. "Another potential of this technology is the extraction of quantitative, information-based texture analysis of MRI," he said. "There are a few thousand textures that can be quantified on MRI. These textures can be combined using appropriate mathematical models for radiomics. Combining radiomics with genetic profiles, referred to as radiogenomics, has the potential to predict outcomes in a number diseases, including cancer, and is a cornerstone of precision medicine." According to Allen, "science as a service" platforms like Agave will enable doctors to capture many kinds of biomedical data in real time and turn them into actionable insights. "Here, we demonstrated this is possible for MRI. But this same idea could be extended to virtually any medical device that gathers patient data," he said. "In a world of big health data and an almost limitless capacity to compute, there is little reason not to leverage high-performance computing resources in the clinic." Explore further: Stampede 2 drives the frontiers of science and engineering forward


Powell B.S.,UTHSC | Lytle N.,UTHSC | Stoikes N.,UTHSC | Webb D.,UTHSC | Voeller G.,UTHSC
Hernia | Year: 2015

Objective: To describe the incidence and treatment of prevascular and retropsoas hernias in a large-volume general surgery practice. Background: Femoral hernias are considered uncommon with an incidence between 2 and 8 % of groin hernias. There are no large studies describing the subtypes of femoral hernias or retropsoas hernias, and therefore no reported incidence or standardized treatment recommendations for these hernias exist. Methods: This study is a retrospective review of all patients undergoing total extraperitoneal (TEP) laparoscopic herniorrhaphy between August 1993 and December 2011. A single surgeon performed all the repairs. Demographics and patient outcomes were reported. Results: 2,436 patients underwent 3,242 TEP repairs. The subtypes were: indirect 1,523 (46.9 %), direct 1,473 (45.4 %), femoral 156 (4.8 %), obturator 35 (1.1 %), prevascular 25 (0.77 %), Spigelian 20 (0.61 %), retropsoas 3 (0.09 %). Prevascular hernias accounted for 16 % of femoral hernias. Patients with prevascular hernias had a mean age of 70.3 years and were all male. 13 of the 25 patients (52 %) with prevascular hernias had other associated defects and four (16 %) of the patients had prevascular hernias as a recurrence from a prior hernia operation. There were three patients with retropsoas hernias that only would not have been seen from an anterior open approach. There are no intraoperative complications or known recurrences from this study group. Conclusions: Prevascular and retropsoas hernias are uncommon, but have a higher incidence than previously believed. Prevascular hernias tend to be associated with older age and other defects. The diagnosis and management of these hernias are readily achieved using the laparoscopic TEP approach. © 2014, Springer-Verlag France.


Purpose. The objective of this study was to compare the salivary protein profiles from individuals diagnosed with breast cancer that were either HER2/neu receptor positive or negative. Methods. Two pooled saliva specimens underwent proteomic analysis. One pooled specimen was from women diagnosed with stage IIa HER2/neu-receptor-positive breast cancer patients (n=10) and the other was from women diagnosed with stage IIa HER2/neu-receptor-negative cancer patients (n=10). The pooled samples were trypsinized and the peptides labeled with iTRAQ reagent. Specimens were analyzed using an LC-MS/MS mass spectrometer. Results. The results yielded approximately 71 differentially expressed proteins in the saliva specimens. There were 34 upregulated proteins and 37 downregulated proteins. © Copyright 2012 Charles F. Streckfus et al.

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