102 results on '"Johnson LP"'
Search Results
2. Effects of massage on pain intensity, analgesics and quality of life in patients with cancer pain: a pilot study of a randomized clinical trial conducted within hospice care delivery.
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Wilkie DJ, Kampbell J, Cutshall S, Halabisky H, Harmon H, Johnson LP, Weinacht L, and Rake-Marona M
- Abstract
Aims: In a randomized controlled clinical trial (RCCT), we examined the effects of tour massages on pain intensity, prescribed IM morphine equivalent doses (IMMSEQ), hospital admissions, and quality of life (QoL). Methods: Of 173 referred patients, 29 (14 control, 15 massage) com pleted this pilot study. Subjects were 69% male and aged 63 years on average. Licensed therapists administered tour, twice-weekly massages. Baseline and outcome measurements were obtained by other team members before the first and after the fourth massages. Results: Pain intensity, pulse rate, and respiratory rate were significantly reduced immediately after the massages. At study entry, the massage group reported higher pain intensity (2.4 +/- 2.8 vs. 1.6 t 2.1) which decreased by 42% (1.4 +/- 1.5) compared to a 25% reduction in the control group (1.2 +/- 1.3) (p > .05). IMMSEQ doses were stable or decreased for eight patients in each group and increased for seven massage and six control group patients. One massage group and two control group patients were hospitalized. All initial QoL scores were higher in the massage group than in the control group, but only current QoL was statistically significant. Both groups reported improved global QoL. The control group reported slight improvement in current QoL and satisfaction with QoL whereas these two aspects of QoL declined in the massage group even though their average QoL scores were higher than the control group at the end of the study. Conclusions: We demonstrated feasibility of conducting an RCCT in which we systematically implemented massage as a nonpharmacologic comfort therapy along with our usual hospice care. The massage intervention produced immediate relaxation and pain relief effects. A power analysis based on trends in the longer-term effects indicate that a study with 80 subjects per group is likely to detect statistically significant effects of usual hospice care with twice-weekly massage therapy sessions on pain intensity, analgesic dosages, and quality of life. Lessons we learned from conducting this pilot study are being used to improve documentation of our hospice program outcomes and to plan a definitive study. [ABSTRACT FROM AUTHOR]
- Published
- 2000
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3. Intraoral ultrasound evaluation of peritonsillar abscess.
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Strong EB, Woodward PJ, Johnson LP, Strong, E B, Woodward, P J, and Johnson, L P
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Peritonsillar cellulitis and peritonsillar abscess are similar clinical entities with markedly different methods of treatment. Therefore, accurate diagnosis is paramount to appropriate treatment. This pilot study was designed to evaluate the sensitivity and specificity of intraoral ultrasound as a noninvasive method of differentiating abscess from cellulitis. Sixteen consecutive patients suspected of having peritonsillar abscess were prospectively evaluated with intraoral ultrasound. The results were confirmed with imaging or surgical drainage. Correct diagnoses were made in 9 (90%) of 10 abscesses and in 5 (83%) of 6 cases of cellulitis. Our results suggest that, while there is a learning curve for intraoral ultrasound, it is an accurate, noninvasive, and inexpensive tool to differentiate abscess from cellulitis. We believe that this will be a clinically useful technique in the future. [ABSTRACT FROM AUTHOR]
- Published
- 1995
4. "We need a little strength as well": Examining the social context of informal caregivers for Black women with breast cancer.
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Thompson T, Coats J, Croston M, Motley RO Jr, Thompson VS, James AS, and Johnson LP
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- Humans, Female, Family psychology, Social Support, Black or African American, Qualitative Research, Caregivers psychology, Breast Neoplasms
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Background: Informal caregivers (e.g., partners, other family members, friends) often provide social support to Black women with breast cancer, and caregivers find both benefits and challenges in their caregiving role., Methods: In this qualitative study, twenty-four caregivers for Black women with breast cancer participated in focus groups and interviews. Participants responded to a brief close-ended questionnaire as well as semi-structured questions about their experiences as cancer caregivers. Demographic information was collected, and relationship satisfaction was measured by the Relationship Assessment Scale-General scale (RAS-G). Focus groups and interviews were recorded, transcribed verbatim, and coded by two independent coders. Using an iterative, discussion-based process, the study team developed and refined themes., Results: All caregivers described themselves as Black/African American, and the majority identified as female (79%). The mean RAS-G score was 4.5 (SD = 0.5), indicating high levels of relationship satisfaction. Qualitative themes included using a range of strategies to provide emotional support; shifting between roles; needing time and space; and trying to stay strong. Several female caregivers described how the cumulative experiences of providing care for multiple family members and friends could be draining, as could their own experiences in the patient role., Conclusions: These findings show a complex, multilayered social context that affects both the patient-caregiver relationship and the health and wellbeing of caregivers. Clinicians providing treatment and support for Black women with breast cancer should be mindful of how the health context of the family may affect patient and caregiver outcomes., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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5. Semantic Categorization of Naming Responses Based on Prearticulatory Electrical Brain Activity.
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Wilmskoetter J, Roth R, McDowell K, Munsell B, Fontenot S, Andrews K, Chang A, Johnson LP, Sangtian S, Behroozmand R, van Mierlo P, Fridriksson J, and Bonilha L
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- Humans, Electroencephalography, Cerebral Cortex, Photic Stimulation, Brain Mapping, Brain physiology, Semantics, Speech physiology
- Abstract
Purpose: Object naming requires visual decoding, conceptualization, semantic categorization, and phonological encoding, all within 400 to 600 ms of stimulus presentation and before a word is spoken. In this study, we sought to predict semantic categories of naming responses based on prearticulatory brain activity recorded with scalp EEG in healthy individuals., Methods: We assessed 19 healthy individuals who completed a naming task while undergoing EEG. The naming task consisted of 120 drawings of animate/inanimate objects or abstract drawings. We applied a one-dimensional, two-layer, neural network to predict the semantic categories of naming responses based on prearticulatory brain activity., Results: Classifications of animate, inanimate, and abstract responses had an average accuracy of 80%, sensitivity of 72%, and specificity of 87% across participants. Across participants, time points with the highest average weights were between 470 and 490 milliseconds after stimulus presentation, and electrodes with the highest weights were located over the left and right frontal brain areas., Conclusions: Scalp EEG can be successfully used in predicting naming responses through prearticulatory brain activity. Interparticipant variability in feature weights suggests that individualized models are necessary for highest accuracy. Our findings may inform future applications of EEG in reconstructing speech for individuals with and without speech impairments., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 by the American Clinical Neurophysiology Society.)
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- 2023
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6. Normative Values for Word Syllable Duration With Interpretation in a Large Sample of Stroke Survivors With Aphasia.
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Haley KL, Jacks A, Kim S, Rodriguez M, and Johnson LP
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- Humans, Reproducibility of Results, Speech, Survivors, Aphasia diagnosis, Aphasia etiology, Apraxias diagnosis, Stroke complications, Stroke diagnosis
- Abstract
Purpose: Slow speech rate and abnormal temporal prosody are primary diagnostic criteria for differentiating between people with aphasia who do and do not have apraxia of speech. We sought to identify appropriate cutoff values for abnormal word syllable duration (WSD) in a word repetition task, interpret them relative to a data set of people with chronic aphasia, and evaluate the extent to which manually derived measures could be approximated through an automated process that relied on commercial speech recognition technology., Method: Fifty neurotypical participants produced 49 multisyllabic words during a repetition task. Audio recordings were submitted to an automated speech recognition (ASR) service (IBM Watson) to measure word duration and generate an orthographic transcription. The transcribed words were compared to a lexical database, and the number of syllables was identified. Automatic and manual measures were compared for 50% of the sample. Results were interpreted relative to WSD scores from an existing data set of 195 people with mostly chronic aphasia., Results: ASR correctly identified 83% of target words and 98% of target syllable counts. Automated word duration calculations were longer than manual measures due to imprecise cursor placement. Upon applying regression coefficients to the automated measures and examining the frequency distributions for both manual and estimated measures, a WSD of 303-316 ms was found to indicate longer-than-normal performance (corresponding to the 95th percentile). With this cutoff, 40%-45% of participants with aphasia in our comparison sample had an abnormally long WSD., Conclusions: We recommend using a rounded WSD cutoff score between 303 and 316 ms for manual measures. Future research will focus on customizing automated WSD methods to speech samples from people with aphasia, identifying target words that maximize production and measurement reliability, and developing WSD standard scores based on a large participant sample with and without aphasia.
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- 2023
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7. Community Gardens: A Catalyst for Community Change.
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Berg AC, Padilla HM, Sanders CE, Garner CT, Southall HG, Holmes G, Ashley S, Crosson L, Twilley B, Everson DD, Hubbard R, Brown CS, Lamm AJ, Johnson LP, and Davis M
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- Humans, Gardening, Public Health, Obesity prevention & control, Gardens, Health Promotion
- Abstract
Community gardens are increasing in popularity and are associated with extensive physical and mental health benefits, increased access to fresh produce, and increased social connections. However, evidence is primarily from research in urban and school settings, and little is known about the role of community gardens in rural settings as part of policy, systems, and environmental (PSE) changes to promote health. This study explores the implementation of community gardens as part of an obesity prevention project, titled Healthier Together (HT), in five rural Georgia counties with limited food access and high obesity prevalence (>40%) using a mixed-methods research design that included data from project records, a community survey, interviews, and focus groups with county coalition members. Nineteen community gardens were implemented across five counties, 89% distributed produce direct to consumers, and 50% were integrated into the food system. Few (8.3%) of the survey respondents (n = 265) identified gardens as a food source, but 21.9% reported using an HT garden in the past year. Themes emerging from interviews (n = 39) and five focus groups suggested community gardens were a catalyst for broader community health change by increasing awareness of the value and absence of healthy food and generating excitement for future PSE initiatives to more comprehensively address food and physical activity access. Practitioners should consider placement of rural community gardens to optimize access to and distribution of produce as well as communication and marketing strategies to increase engagement and leverage gardens as gateways for PSE approaches to improve rural health.
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- 2023
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8. Neural network bases of thematic semantic processing in language production.
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Schwen Blackett D, Varkey J, Wilmskoetter J, Roth R, Andrews K, Busby N, Gleichgerrcht E, Desai RH, Riccardi N, Basilakos A, Johnson LP, Kristinsson S, Johnson L, Rorden C, Spell LA, Fridriksson J, and Bonilha L
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- Humans, Adult, Language, Semantics, Brain Mapping, Magnetic Resonance Imaging, Neural Networks, Computer, Aphasia etiology, Connectome
- Abstract
Semantic processing is a central component of language and cognition. The anterior temporal lobe is postulated to be a key hub for semantic processing, but the posterior temporoparietal cortex is also involved in thematic associations during language. It is possible that these regions act in concert and depend on an anteroposterior network linking the temporal pole with posterior structures to support thematic semantic processing during language production. We employed connectome-based lesion-symptom mapping to examine the causal relationship between lesioned white matter pathways and thematic processing language deficits among individuals with post-stroke aphasia. Seventy-nine adults with chronic aphasia completed the Philadelphia Naming Test, and semantic errors were coded as either thematic or taxonomic to control for taxonomic errors. Controlling for nonverbal conceptual-semantic knowledge as measured by the Pyramids and Palm Trees Test, lesion size, and the taxonomic error rate, thematic error rate was associated with loss of white matter connections from the temporal pole traversing in peri-Sylvian regions to the posterior cingulate and the insula. These findings support the existence of a distributed network underlying thematic relationship processing in language as opposed to discrete cortical areas., Competing Interests: Declaration of competing interest The authors report no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
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- 2022
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9. Defining the Neurobiological Mechanisms of Action in Aphasia Therapies: Applying the Rehabilitation Treatment Specification System Framework to Research and Practice in Aphasia.
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Basilakos A, Hula WD, Johnson LP, Kiran S, Walker GM, and Fridriksson J
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- Behavior Therapy, Humans, Aphasia rehabilitation
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The Rehabilitation Treatment Specification System (RTSS) was developed as a systematic way to describe rehabilitation treatments for the purpose of both research and practice. The RTSS groups treatments by type and describes them by 3 elements: the treatment (1) ingredients and (2) the mechanisms of action that yield changes in the (3) target behavior. Adopting the RTSS has the potential to improve consistency in research, allowing for better cross-study comparisons to strengthen the body of research supporting various treatments. Because it is still early in its development, the RTSS has not yet been widely implemented across different rehabilitation disciplines. In particular, aphasia recovery is one area of rehabilitation that could benefit from a unifying framework. Accordingly, this article is part of a series where we illustrate how the RTSS can be applied to aphasia treatment and research. This article more specifically focuses on examining the neurobiological mechanisms of action associated with experimental aphasia therapies, including brain stimulation and pharmacologic intervention, as well as more traditional behavioral therapy. Key elements of the RTSS are described, and 4 example studies are used to illustrate how the RTSS can be implemented. The benefits of a unifying framework for the future of aphasia treatment research and practice are discussed., (Copyright © 2021 The American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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10. Demystifying the Complexity of Aphasia Treatment: Application of the Rehabilitation Treatment Specification Systemx.
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Fridriksson J, Basilakos A, Boyle M, Cherney LR, DeDe G, Gordon JK, Harnish SM, Hoover EL, Hula WD, Pompon RH, Johnson LP, Kiran S, Murray LL, Rose ML, Obermeyer J, Salis C, Walker GM, and Martin N
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- Communication, Humans, Aphasia rehabilitation, Cognitive Behavioral Therapy
- Abstract
A considerable body of research supports the use of behavioral communication treatment as the standard of care for aphasia. In spite of robust progress in clinical aphasiology, many questions regarding optimal care remain unanswered. One of the major challenges to progress in the field is the lack of a common framework to adequately describe individual treatments, which, if available, would allow comparisons across studies as well as improved communication among researchers, clinicians, and other stakeholders. Here, we describe how aphasia treatment approaches can be systematically characterized using the Rehabilitation Treatment Specification System (RTSS). At the core of the RTSS is a tripartite structure that focuses on targets (the behavior that is expected to change as a result of treatment), ingredients (what a clinician does to affect change in the target), and mechanism(s) of action (why a given treatment works by linking the ingredients to the target). Three separate articles in the current issue specifically describe how the RTSS can be used to describe different kinds of aphasia treatment approaches: functional approaches, cognitive-linguistic approaches, and biological approaches. It is our hope that the application of the RTSS in clinical aphasiology will improve communication in published studies, grant proposals, and in the clinical care of persons with aphasia., (Copyright © 2021 The American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)
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- 2022
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11. Language Recovery after Brain Injury: A Structural Network Control Theory Study.
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Wilmskoetter J, He X, Caciagli L, Jensen JH, Marebwa B, Davis KA, Fridriksson J, Basilakos A, Johnson LP, Rorden C, Bassett D, and Bonilha L
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- Acoustic Stimulation methods, Adult, Aged, Brain physiology, Connectome methods, Female, Follow-Up Studies, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Nerve Net physiology, Photic Stimulation methods, Brain diagnostic imaging, Brain Injuries diagnostic imaging, Brain Injuries therapy, Language, Nerve Net diagnostic imaging, Recovery of Function physiology
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Aphasia recovery after stroke depends on the condition of the remaining, extralesional brain network. Network control theory (NCT) provides a unique, quantitative approach to assess the interaction between brain networks. In this longitudinal, large-scale, whole-brain connectome study, we evaluated whether controllability measures of language-related regions are associated with treated aphasia recovery. Using probabilistic tractography and controlling for the effects of structural lesions, we reconstructed whole-brain diffusion tensor imaging (DTI) connectomes from 68 individuals (20 female, 48 male) with chronic poststroke aphasia who completed a three-week language therapy. Applying principles of NCT, we computed regional (1) average and (2) modal controllability, which decode the ability of a region to (1) spread control input through the brain network and (2) to facilitate brain state transitions. We tested the relationship between pretreatment controllability measures of 20 language-related left hemisphere regions and improvements in naming six months after language therapy using multiple linear regressions and a parsimonious elastic net regression model with cross-validation. Regional controllability of the inferior frontal gyrus (IFG) pars opercularis, pars orbitalis, and the anterior insula were associated with treatment outcomes independently of baseline aphasia severity, lesion volume, age, education, and network size. Modal controllability of the IFG pars opercularis was the strongest predictor of treated aphasia recovery with cross-validation and outperformed traditional graph theory, lesion load, and demographic measures. Regional NCT measures can reflect the status of the residual language network and its interaction with the remaining brain network, being able to predict language recovery after aphasia treatment. SIGNIFICANCE STATEMENT Predicting and understanding language recovery after brain injury remains a challenging, albeit a fundamental aspect of human neurology and neuroscience. In this study, we applied network control theory (NCT) to fully harness the concept of brain networks as dynamic systems and to evaluate their interaction. We studied 68 stroke survivors with aphasia who underwent imaging and longitudinal behavioral assessments coupled with language therapy. We found that the controllability of the inferior frontal regional network significantly predicted recovery in language production six months after treatment. Importantly, controllability outperformed traditional demographic, lesion, and graph-theoretical measures. Our findings shed light on the neurobiological basis of human language and can be translated into personalized rehabilitation approaches., (Copyright © 2022 the authors.)
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- 2022
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12. Electrophysiologic evidence of reorganization in poststroke aphasia.
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Johnson LP and Fridriksson J
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- Evoked Potentials, Humans, Language, Aphasia etiology, Aphasia therapy, Electric Stimulation Therapy, Stroke complications, Stroke therapy
- Abstract
Electrophysiologic methods have been used to investigate neural changes in individuals with poststroke aphasia. The major types of electrophysiologic measures include the event-related potential (ERP) and spectral power, and aspects of both (including amplitude, topography, and power) have been shown to differ in people with aphasia. Not only that, these measures are sensitive to spontaneous and treatment-induced language change. The purpose of this chapter is to review evidence of poststroke reorganization in the language network that has been identified in the acute and chronic phases of poststroke aphasia. The chapter will begin with a brief introduction to electrophysiologic methods and then focus on evidence from the most commonly studied ERPs and spectral bands in aphasia., (Copyright © 2022 Elsevier B.V. All rights reserved.)
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- 2022
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13. Topological signal processing and inference of event-related potential response.
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Wang Y, Behroozmand R, Johnson LP, Bonilha L, and Fridriksson J
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- Attention, Electroencephalography, Humans, Signal Processing, Computer-Assisted, Evoked Potentials, Speech
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Background: Topological signal processing is a novel approach for decoding multiscale features of signals recorded through electroencephalography (EEG) based on topological data analysis (TDA). New method: We establish stability properties of the TDA descriptor persistence landscape (PL) in event-related potential (ERP) across multi-trial EEG signals, state algorithms for computing PL, and propose an exact inference framework on persistence and PLs., Results: We apply the topological signal processing and inference framework to compare ERPs between individuals with post-stroke aphasia and healthy controls under a speech altered auditory feedback (AAF) paradigm. Results show significant PL difference in the ERP response of aphasic individuals and healthy controls over the parietal-occipital and occipital regions with respect to speech onset, and no significant PL difference in any regions with respect to the two pitch-shift stimuli. Comparison with existing methods: In comparison, spatial patterns of difference between aphasic individuals and healthy controls by persistence, local variance, and spectral powers are much more diffuse than the PL patterns. In simulation results, the exact test on persistence and PLs has more robust performance than the baseline tests on local variance and spectral powers., Conclusions: Persistence features provide a more robust EEG marker than local variance, and spectral powers. It could be a potentially powerful tool for comparing electrophysiological correlates in neurological disorders., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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14. Cortical microstructural changes associated with treated aphasia recovery.
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Chang AJ, Wilmskoetter J, Fridriksson J, McKinnon ET, Johnson LP, Basilakos A, Jensen JH, Rorden C, and Bonilha L
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- Adult, Aged, Aphasia etiology, Aphasia physiopathology, Diffusion Magnetic Resonance Imaging, Humans, Longitudinal Studies, Male, Middle Aged, Outcome Assessment, Health Care, Psycholinguistics, Recovery of Function physiology, Retrospective Studies, Stroke pathology, Stroke physiopathology, Stroke therapy, Temporal Lobe diagnostic imaging, Aphasia pathology, Aphasia rehabilitation, Stroke complications, Stroke Rehabilitation, Temporal Lobe pathology
- Abstract
Objectives: To investigate the hypothesis that language recovery in post-stroke aphasia is associated with structural brain changes., Methods: We evaluated whether treatment-induced improvement in naming is associated with reorganization of tissue microstructure within residual cortical regions. To this end, we performed a retrospective longitudinal treatment study using comprehensive language-linguistic assessments and diffusion MRI sequences optimized for the assessment of complex microstructure (diffusional kurtosis imaging) to evaluate the relationship between language treatment response and cortical changes in 26 individuals with chronic stroke-induced aphasia. We employed elastic net statistical models controlling for baseline factors including age, sex, and time since the stroke, as well as lesion volume., Results: We observed that improved naming accuracy (Philadelphia Naming Test) was statistically associated with increased post-treatment microstructural integrity in the left posterior superior temporal gyrus. Moreover, increase in microstructural integrity in the left middle temporal gyrus and left inferior temporal gyrus was specifically associated with a decrease in semantic paraphasias. This longitudinal relationship between brain tissue integrity and language improvement was not observed in other non-language related brain regions., Interpretation: Our findings provide evidence that structural brain changes in the preserved left hemisphere regions are associated with treatment-induced language recovery in aphasia and are part of the mechanisms supporting language and brain injury recovery., (© 2021 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)
- Published
- 2021
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15. What Anansi Did for Us: Storytelling's Value in Equitably Exploring Public Health.
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Fakunle DO, Thomas Mph DT, Gonzales KAM, Vidot DC, and Johnson LP
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- Communication, Humans, Population Groups, Narration, Public Health
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There is growing implementation of storytelling as a specific application of narrative in public health. As the field's latest epoch evolves to consider cultural determinants, reimagination of how scientists conceptualize, operationalize, and capture populations' unique elements is necessary, and storytelling provides a genuine and efficacious methodology that can assist with that reimagination. Professionals are creating more spaces that demonstrate how storytelling elucidates, promotes, and supports contextual factors that are not captured by orthodox methodologies. However, more opportunities are needed to exhibit storytelling's impact on capturing the nuances in human experiences, such as those of historically and systemically underrepresented populations. This study synthesizes the past decade of research in public health and related fields that primarily utilized storytelling and reports significant implications. Additionally, this study highlights explorations in public health that primarily use storytelling as a research and practice approach. Each case study includes a description of the background and aims, elaborates on storytelling's utilization, and discusses findings, observations, and future directions. Finally, this study discusses conceptual issues in public health raised by use of storytelling, such as how to best capture impact on human beings and the importance of context. This article's goal is to present current evidence of critical reevaluations to the epistemological, conceptual, and practical paradigms within public health through storytelling. Additionally, this article aims to provide support and empowerment to public health scientists considering creative approaches to better acknowledge and appreciate humanity's inherent subjectivity.
- Published
- 2021
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16. Slowed Compensation Responses to Altered Auditory Feedback in Post-Stroke Aphasia: Implications for Speech Sensorimotor Integration.
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Johnson LP, Sangtian S, Johari K, Behroozmand R, and Fridriksson J
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- Adult, Aged, Female, Humans, Male, Middle Aged, Speech, Aphasia, Feedback, Sensory, Stroke
- Abstract
Developing a clearer understanding of impairments that underlie the behavioral characteristics of aphasia is essential for the development of targeted treatments and will help inform theories of speech motor control. Impairments in sensorimotor integration of speech in individuals with conduction aphasia have previously been implicated in their repetition deficits. However, much less is known about the extent to which these integrative deficits occur outside of conduction aphasia and how this manifests behaviorally in areas other than speech repetition. In this study, we aimed to address these issues by examining the behavioral correlates of speech sensorimotor impairment under altered auditory feedback (AAF) and their relationship with the impaired ability to independently correct for online errors during picture naming in people with aphasia. We found that people with aphasia generate slower vocal compensation response to pitch-shift AAF stimuli compared with controls. However, when the timing of responses was controlled for, no significant difference in the magnitude of vocal pitch compensation was observed between aphasia and control groups. Moreover, no relationship was found between self-correction of naming errors and the timing and magnitude of vocal compensation responses to AAF. These findings suggest that slowed compensation is a potential behavioral marker of impaired sensorimotor integration in aphasia., (Copyright © 2020 Elsevier Inc. All rights reserved.)
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- 2020
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17. The Prevalence and Impact of Hepatic Steatosis on Response to Direct-Acting Antiviral Therapy in HIV-HCV Coinfection.
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Johnson LP and Sterling RK
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(1) Background: Direct-acting antiviral therapy for chronic hepatitis C virus (HCV) infection is associated with high sustained virologic response (SVR) and overcomes negative predictive factors, including steatosis, in patients without human immunodeficiency virus (HIV) coinfection. The impact of steatosis on SVR in patients with HIV-HCV coinfection is unknown. (2) Methods: A retrospective analysis of patients treated with direct-acting antivirals was performed. Demographic, laboratory and direct-acting antiviral regimen data were prospectively collected. Metabolic syndrome and its components-diabetes mellitus, hypertension, dyslipidemia and obesity-were assessed. Hepatic steatosis (≥5%) was defined by liver biopsy or controlled attenuation parameter (CAP) measurement during vibration-controlled transient elastography (VCTE). (3) Results: A total of 151 HIV-HCV-coinfected patients on combined antiretroviral therapy and direct-acting antiviral therapy were included in this analysis. Prevalence of steatosis by liver biopsy (n = 34) or CAP (≥263 db/m) during VCTE (n = 92) was 27% and was independently associated with obesity (OR 3.11; 95% CI 1.43-6.82; p = 0.004) and the metabolic syndrome (OR 1.08; 95% CI 1.01-0.15; p = 0.01). The overall SVR rate (n = 148) was 95% and was not impacted by the presence of steatosis ( p = 0.42). (4) Conclusions: Hepatic steatosis is common in HIV-HCV coinfection, correlates with obesity and the metabolic syndrome and does not impact SVR.
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- 2020
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18. Small white spots on the lips.
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Cyr PR and Johnson LP
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- Adult, Female, Humans, Lip, Sebaceous Glands
- Published
- 2019
19. Pre-surgical, surgical and post-surgical experiences of weight loss surgery patients: a closer look at social determinants of health.
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Johnson LP, Asigbee FM, Crowell R, and Negrini A
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- Adult, Aged, Bariatric Surgery economics, Bariatric Surgery psychology, Comorbidity, Female, Humans, Income, Interviews as Topic, Male, Middle Aged, Obesity economics, Obesity physiopathology, Photography, Postoperative Period, Preoperative Period, Qualitative Research, Weight Loss, Obesity psychology, Obesity surgery, Social Determinants of Health
- Abstract
Using a novel qualitative approach, Photovoice, researchers assessed social, psychological, physical and economic barriers encountered by patients of weight loss surgery. Applying the Photovoice approach and Williams' theory of narrative reconstruction for qualitative interviewing, the research team set out to investigate the bariatric patient experience from pre-surgery to hospitalization to post-surgery. Fifteen participants were given digital cameras and asked to take photographs that represented their weight loss journeys. Photographs and qualitative interviews were used to theorize the role played by comorbidities, social determinants of health, provider communication experiences and understanding of insurance coverage in patient outcomes. Several themes emerged from the interviews and photographs including themes centred around: (i) racial/ethnic standards of beauty; (ii) gender expectations; (iii) comorbidities, depression/disordered eating and obesity discrimination and (iv) financial hardship impacting adherence. Photographs also illuminated the impact of hospital and state-wide policies on patient lives. Results suggest that Photovoice may be a useful adjunct to standard-of-care to help patients identify barriers, and to identify shortcomings in health services. Additional screening tools for gender- and income-related barriers (and concomitant referrals to support services) provide an opportunity to improve patient care and reduce post-operative readmissions., (© 2018 World Obesity Federation.)
- Published
- 2018
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20. Community change and resident needs: Designing a Participatory Action Research study in Metropolitan Boston.
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Arcaya MC, Schnake-Mahl A, Binet A, Simpson S, Church MS, Gavin V, Coleman B, Levine S, Nielsen A, Carroll L, Ursprung S, Wood B, Reeves H, Keppard B, Sportiche N, Partirdge J, Figueora J, Frakt A, Alfonzo M, Abreu D, Abreu T, Ambroise T, Andrade E, Barrientos E, Baty A, Baty C, Benner K, Bennett C, Blanchette A, Bongiovanni R, Cardile O, Corchado C, Dixon C, Dodson C, Dominguez J, Durena M, Fiestas Y, Genty J, Graffam N, Gonzalez A, Grigsby E, Hayden P, Alvado SH, Hernandez Z, Hodes I, Johnson J, Keefe K, Latimer K, Levine S, Logg C, Martinez N, Mboup K, McPhorson D, Meacham S, Mohammed D, Moss E, Nielsen A, O'Brien K, Owens L, Partridge J, Johnson LP, Power MB, Rebelo T, Remy R, Roderigues G, Sabtow Q, Sanchez C, Seeder A, Sepulveda R, Sportiche N, Ursprung S, West E, Winters L, Wood B, and Youmans T
- Subjects
- Adolescent, Adult, Black or African American, Aged, Aged, 80 and over, Boston, Community-Based Participatory Research, Community-Institutional Relations, Female, Food Supply, Hispanic or Latino, Humans, Linear Models, Male, Mental Health, Middle Aged, Program Development, Self Report, Social Support, Urban Population, Young Adult, Health Status, Poverty statistics & numerical data, Residence Characteristics statistics & numerical data, Social Change, Urban Renewal
- Abstract
The health implications of urban development, particularly in rapidly changing, low-income urban neighborhoods, are poorly understood. We describe the Healthy Neighborhoods Study (HNS), a Participatory Action Research study examining the relationship between neighborhood change and population health in nine Massachusetts neighborhoods. Baseline data from the HNS survey show that social factors, specifically income insecurity, food insecurity, social support, experiencing discrimination, expecting to move, connectedness to the neighborhood, and local housing construction that participants believed would improve their lives, identified by a network of 45 Resident Researchers exhibited robust associations with self-rated and mental health. Resident-derived insights into relationships between neighborhoods and health may provide a powerful mechanism for residents to drive change in their communities., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2018
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21. Pre-clinical development of a hydrogen peroxide-inactivated West Nile virus vaccine.
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Poore EA, Slifka DK, Raué HP, Thomas A, Hammarlund E, Quintel BK, Torrey LL, Slifka AM, Richner JM, Dubois ME, Johnson LP, Diamond MS, Slifka MK, and Amanna IJ
- Subjects
- Animals, Anti-Infective Agents, Local metabolism, Antibodies, Neutralizing blood, Antibodies, Viral blood, Disease Models, Animal, Drug Evaluation, Preclinical, Drug Stability, Drug-Related Side Effects and Adverse Reactions pathology, Female, Hot Temperature, Hydrogen Peroxide metabolism, Macaca mulatta, Male, Mice, Inbred BALB C, Rats, Sprague-Dawley, Survival Analysis, United States, Vaccine Potency, Vaccines, Inactivated administration & dosage, Vaccines, Inactivated adverse effects, Vaccines, Inactivated immunology, Vaccines, Inactivated isolation & purification, Viremia prevention & control, West Nile Virus Vaccines administration & dosage, West Nile Virus Vaccines adverse effects, West Nile Virus Vaccines isolation & purification, West Nile Fever prevention & control, West Nile Virus Vaccines immunology
- Abstract
West Nile virus (WNV) is a mosquito-transmitted pathogen with a wide geographical range that can lead to long-term disability and death in some cases. Despite the public health risk posed by WNV, including an estimated 3 million infections in the United States alone, no vaccine is available for use in humans. Here, we present a scaled manufacturing approach for production of a hydrogen peroxide-inactivated whole virion WNV vaccine, termed HydroVax-001WNV. Vaccination resulted in robust virus-specific neutralizing antibody responses and protection against WNV-associated mortality in mice or viremia in rhesus macaques (RM). A GLP-compliant toxicology study performed in rats demonstrated an excellent safety profile with clinical findings limited to minor and transient irritation at the injection site. An in vitro relative potency (IVRP) assay was developed and shown to correlate with in vivo responses following forced degradation studies. Long-term in vivo potency comparisons between the intended storage condition (2-8°C) and a thermally stressed condition (40±2°C) demonstrated no loss in vaccine efficacy or protective immunity over a 6-month span of time. Together, the positive pre-clinical findings regarding immunogenicity, safety, and stability indicate that HydroVax-001WNV is a promising vaccine candidate., Competing Interests: This potential individual and institutional conflict of interest has been reviewed and managed by OHSU. HPR, AT, JMR, and MSD declare no relevant conflicts of interest., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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22. Prebiotics Modulate the Effects of Antibiotics on Gut Microbial Diversity and Functioning in Vitro.
- Author
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Johnson LP, Walton GE, Psichas A, Frost GS, Gibson GR, and Barraclough TG
- Subjects
- Ampicillin pharmacology, Anti-Bacterial Agents pharmacology, Bacteria classification, Bacteria drug effects, Bacteria isolation & purification, DNA, Bacterial genetics, Dietary Carbohydrates administration & dosage, Fatty Acids, Volatile metabolism, Feces microbiology, Fermentation, Gentamicins pharmacology, Humans, Inulin pharmacology, Pectins pharmacology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Anti-Bacterial Agents adverse effects, Gastrointestinal Hormones metabolism, Gastrointestinal Microbiome drug effects, Prebiotics
- Abstract
Intestinal bacteria carry out many fundamental roles, such as the fermentation of non-digestible dietary carbohydrates to produce short chain fatty acids (SCFAs), which can affect host energy levels and gut hormone regulation. Understanding how to manage this ecosystem to improve human health is an important but challenging goal. Antibiotics are the front line of defence against pathogens, but in turn they have adverse effects on indigenous microbial diversity and function. Here, we have investigated whether dietary supplementation--another method used to modulate gut composition and function--could be used to ameliorate the side effects of antibiotics. We perturbed gut bacterial communities with gentamicin and ampicillin in anaerobic batch cultures in vitro. Cultures were supplemented with either pectin (a non-fermentable fibre), inulin (a commonly used prebiotic that promotes the growth of beneficial bacteria) or neither. Although antibiotics often negated the beneficial effects of dietary supplementation, in some treatment combinations, notably ampicillin and inulin, dietary supplementation ameliorated the effects of antibiotics. There is therefore potential for using supplements to lessen the adverse effects of antibiotics. Further knowledge of such mechanisms could lead to better therapeutic manipulation of the human gut microbiota.
- Published
- 2015
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23. Impacts of plant-based foods in ancestral hominin diets on the metabolism and function of gut microbiota in vitro.
- Author
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Frost GS, Walton GE, Swann JR, Psichas A, Costabile A, Johnson LP, Sponheimer M, Gibson GR, and Barraclough TG
- Subjects
- Animals, Bacteria metabolism, Biodiversity, Biomass, Fatty Acids biosynthesis, Humans, Male, Metabolomics, Mice, Peptide YY metabolism, Theropithecus, Animal Feed, Gastrointestinal Tract metabolism, Hominidae, Microbiota, Plants, Edible
- Abstract
Unlabelled: Ancestral human populations had diets containing more indigestible plant material than present-day diets in industrialized countries. One hypothesis for the rise in prevalence of obesity is that physiological mechanisms for controlling appetite evolved to match a diet with plant fiber content higher than that of present-day diets. We investigated how diet affects gut microbiota and colon cells by comparing human microbial communities with those from a primate that has an extreme plant-based diet, namely, the gelada baboon, which is a grazer. The effects of potato (high starch) versus grass (high lignin and cellulose) diets on human-derived versus gelada-derived fecal communities were compared in vitro. We especially focused on the production of short-chain fatty acids, which are hypothesized to be key metabolites influencing appetite regulation pathways. The results confirmed that diet has a major effect on bacterial numbers, short-chain fatty acid production, and the release of hormones involved in appetite suppression. The potato diet yielded greater production of short-chain fatty acids and hormone release than the grass diet, even in the gelada cultures, which we had expected should be better adapted to the grass diet. The strong effects of diet on hormone release could not be explained, however, solely by short-chain fatty acid concentrations. Nuclear magnetic resonance spectroscopy found changes in additional metabolites, including betaine and isoleucine, that might play key roles in inhibiting and stimulating appetite suppression pathways. Our study results indicate that a broader array of metabolites might be involved in triggering gut hormone release in humans than previously thought., Importance: One theory for rising levels of obesity in western populations is that the body's mechanisms for controlling appetite evolved to match ancestral diets with more low-energy plant foods. We investigated this idea by comparing the effects of diet on appetite suppression pathways via the use of gut bacterial communities from humans and gelada baboons, which are modern-day primates with an extreme diet of low-energy plant food, namely, grass. We found that diet does play a major role in affecting gut bacteria and the production of a hormone that suppresses appetite but not in the direction predicted by the ancestral diet hypothesis. Also, bacterial products were correlated with hormone release that were different from those normally thought to play this role. By comparing microbiota and diets outside the natural range for modern humans, we found a relationship between diet and appetite pathways that was more complex than previously hypothesized on the basis of more-controlled studies of the effects of single compounds., (Copyright © 2014 Frost et al.)
- Published
- 2014
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24. Effect of caffeine on adenosine-induced reversible perfusion defects assessed by automated analysis.
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Lee JC, Fraser JF, Barnett AG, Johnson LP, Wilson MG, McHenry CM, Walters DL, Warnholtz CR, and Khafagi FA
- Subjects
- Blood Flow Velocity drug effects, Drug Interactions, Female, Humans, Image Interpretation, Computer-Assisted methods, Male, Middle Aged, Reproducibility of Results, Sensitivity and Specificity, Vasodilator Agents administration & dosage, Adenosine administration & dosage, Caffeine administration & dosage, Coronary Artery Disease diagnostic imaging, Coronary Artery Disease physiopathology, Coronary Circulation drug effects, Exercise Test drug effects, Myocardial Perfusion Imaging methods
- Abstract
Objectives: This prospective study investigated the effects of caffeine ingestion on the extent of adenosine-induced perfusion abnormalities during myocardial perfusion imaging (MPI)., Methods: Thirty patients with inducible perfusion abnormalities on standard (caffeineabstinent) adenosine MPI underwent repeat testing with supplementary coffee intake. Baseline and test MPIs were assessed for stress percent defect, rest percent defect, and percent defect reversibility. Plasma levels of caffeine and metabolites were assessed on both occasions and correlated with MPI findings., Results: Despite significant increases in caffeine [mean difference 3,106 μg/L (95% CI 2,460 to 3,752 μg/L; P < .001)] and metabolite concentrations over a wide range, there was no statistically significant change in stress percent defect and percent defect reversibility between the baseline and test scans. The increase in caffeine concentration between the baseline and the test phases did not affect percent defect reversibility (average change -0.003 for every 100 μg/L increase; 95% CI -0.17 to 0.16; P = .97)., Conclusion: There was no significant relationship between the extent of adenosine-induced coronary flow heterogeneity and the serum concentration of caffeine or its principal metabolites. Hence, the stringent requirements for prolonged abstinence from caffeine before adenosine MPI - based on limited studies - appear ill-founded.
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- 2012
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25. Canine parvovirus-2b-associated erythema multiforme in a litter of English Setter dogs.
- Author
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Woldemeskel M, Liggett A, Ilha M, Saliki JT, and Johnson LP
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- Animals, Animals, Newborn virology, Dog Diseases diagnosis, Dog Diseases pathology, Dogs virology, Erythema Multiforme etiology, Erythema Multiforme pathology, Erythema Multiforme virology, Female, Fluorescent Antibody Technique veterinary, Male, Microscopy, Electron veterinary, Parvoviridae Infections complications, Parvoviridae Infections pathology, Parvoviridae Infections virology, Polymerase Chain Reaction veterinary, Skin pathology, Dog Diseases virology, Erythema Multiforme veterinary, Parvoviridae Infections veterinary, Parvovirus, Canine
- Abstract
Erythema multiforme (EM) was diagnosed in a litter of English Setter puppies. The puppies developed erythematous cutaneous lesions at the age of 2 weeks. Microscopically, there was individual keratinocyte apoptosis associated with lymphocyte exocytosis in all layers of the epidermis. Intranuclear viral inclusions were seen in multiple tissues and organs. Tissues from the tongue, lymph node, spleen, skin, and small intestine were positive for Canine parvovirus-2 (CPV-2) and negative for Canine distemper virus (CDV) and Canid herpesvirus 1 by fluorescent antibody test. Negative-staining electron microscopy detected parvovirus particles in the intestinal contents. The skin and small intestine were positive for CPV-2b and negative for CDV by polymerase chain reaction. The mucocutaneous junctions and small intestines stained positive for CPV by immunohistochemistry. The present report documents CPV-2b-associated EM in a litter of English Setters and substantiates the single previous report associating EM with CPV-2. The finding suggests that CPV should be considered as a possible cause of EM in dogs., (© 2011 The Author(s))
- Published
- 2011
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26. Torque teno virus 10 isolated by genome amplification techniques from a patient with concomitant chronic lymphocytic leukemia and polycythemia vera.
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Chu CC, Zhang L, Dhayalan A, Agagnina BM, Magli AR, Fraher G, Didier S, Johnson LP, Kennedy WJ, Damle RN, Yan XJ, Patten PE, Teichberg S, Koduru P, Kolitz JE, Allen SL, Rai KR, and Chiorazzi N
- Subjects
- Aged, Aged, 80 and over, Blood Donors, Case-Control Studies, DNA Virus Infections blood, DNA Virus Infections complications, DNA Virus Infections virology, DNA, Viral blood, DNA, Viral genetics, Female, Humans, Leukemia, Lymphocytic, Chronic, B-Cell blood, Leukemia, Lymphocytic, Chronic, B-Cell virology, Male, Middle Aged, Polycythemia Vera blood, Reproducibility of Results, Genome, Viral genetics, Leukemia, Lymphocytic, Chronic, B-Cell complications, Nucleic Acid Amplification Techniques methods, Polycythemia Vera complications, Polycythemia Vera virology, Torque teno virus genetics, Torque teno virus isolation & purification
- Abstract
An infectious etiology has been proposed for many human cancers, but rarely have specific agents been identified. One difficulty has been the need to propagate cancer cells in vitro to produce the infectious agent in detectable quantity. We hypothesized that genome amplification from small numbers of cells could be adapted to circumvent this difficulty. A patient with concomitant chronic lymphocytic leukemia (CLL) and polycythemia vera (PV) requiring therapeutic phlebotomy donated a large amount of phlebotomized blood to test this possibility. Using genome amplification methods, we identified a new isolate (BIS8-17) of torque teno virus (TTV) 10. The presence of blood isolate sequence 8-17 (BIS8-17) in the original plasma was confirmed by polymerase chain reaction (PCR), validating the approach, since TTV is a known plasma virus. Subsequent PCR testing of plasmas from additional patients showed that BIS8-17 had a similar incidence (~20%) in CLL (n = 48) or PV (n = 10) compared with healthy controls (n = 52). CLL cells do not harbor BIS8-17; PCR did not detect it in CLL peripheral blood genomic deoxyribonucleic acid (DNA) (n = 20). CLL patient clinical outcome or prognostic markers (immunoglobulin heavy chain variable region [IGHV ] mutation, CD38 or zeta-chain associated protein kinase 70 kDa [ZAP-70]) did not correlate with BIS8-17 infection. Although not causative to our knowledge, this is the first reported isolation and detection of TTV in either CLL or PV. TTV could serve as a covirus with another infectious agent or TTV variant with rearranged genetic components that contribute to disease pathogenesis. These results prove that this method identifies infectious agents and provides an experimental methodology to test correlation with disease.
- Published
- 2011
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27. Penetrating trauma to the head and neck from a nail gun: a unique mechanism of injury.
- Author
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Buchalter GM, Johnson LP, Reichman MV, and Jacobs J
- Subjects
- Adolescent, Cerebral Angiography, Craniocerebral Trauma etiology, Craniocerebral Trauma surgery, Follow-Up Studies, Humans, Injury Severity Score, Male, Neck Injuries etiology, Neck Injuries surgery, Risk Assessment, Surgical Procedures, Operative, Tomography, X-Ray Computed, Treatment Outcome, Wounds, Penetrating etiology, Wounds, Penetrating surgery, Construction Materials, Craniocerebral Trauma diagnosis, Neck Injuries diagnosis, Wounds, Penetrating diagnosis
- Abstract
Published reports of nail gun injuries to the head and neck are rare. We describe the cases of three patients who sustained nail gun injuries to the head and who were managed at our institution. All patients were treated successfully and all recovered with minimal morbidity. Any physician who is called on to manage a nail gun injury to the head or neck should understand that most likely the patient will have sustained a surprisingly limited amount of tissue injury, owing to the relatively low velocity of the projectile compared with that delivered by firearms. Computed tomography and selective angiography can play a vital role in assessing the integrity of relevant vascular structures. Moreover, catheter angiography with embolization can be a most useful nonsurgical adjunct to control the extent of vascular injury.
- Published
- 2002
28. Pathology quiz case 1: nasoalveolar cyst.
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Hillman T, Galloway EB, and Johnson LP
- Subjects
- Aged, Cysts diagnostic imaging, Cysts surgery, Humans, Jaw Diseases diagnostic imaging, Jaw Diseases surgery, Male, Nose Diseases diagnostic imaging, Nose Diseases surgery, Tomography, X-Ray Computed, Alveolar Process, Cysts pathology, Jaw Diseases pathology, Nose Diseases pathology
- Published
- 2002
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29. Urban air: real samples for undergraduate analytical chemistry.
- Author
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Hope WW and Johnson LP
- Subjects
- Environmental Monitoring, Air Pollutants analysis, Chemistry, Analytic education
- Published
- 2000
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30. Methimazole and propylthiouracil equally cross the perfused human term placental lobule.
- Author
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Mortimer RH, Cannell GR, Addison RS, Johnson LP, Roberts MS, and Bernus I
- Subjects
- Animals, Female, Humans, In Vitro Techniques, Maternal-Fetal Exchange, Models, Biological, Perfusion, Pregnancy, Serum Albumin metabolism, Serum Albumin, Bovine metabolism, Antithyroid Agents pharmacokinetics, Delivery, Obstetric, Methimazole pharmacokinetics, Placenta metabolism, Propylthiouracil pharmacokinetics
- Abstract
Propylthiouracil (PTU) is widely believed to cross the placenta less freely than methimazole (MMI) and is therefore regarded as the preferred drug for treatment of hyperthyroidism in pregnancy. Clinical studies comparing the two drugs show, however, no differences in maternal or fetal thyroid function. We investigated transfer from the maternal to the fetal circuit in the isolated perfused term human placental lobule of low and high doses of PTU (4 micrograms/mL and 40 micrograms/mL) and MMI (1.5 micrograms/mL and 15 micrograms/mL) in protein-free perfusate and low doses of both drugs with addition of 40 g/L of bovine albumin. Both drugs readily crossed the placenta, reaching equilibrium in all experiments in about 2 h. Drug concentrations in the two circuits fitted a two compartmental model. Transfer kinetics for the two drugs were similar, nonsaturable, and unaffected by addition of albumin. Clearances (mL.min-1.g-1, means +/- SD) of PTU from maternal to fetal circuits were: 0.229 +/- 0.110, 0.216 +/- 0.065, and 0.170 +/- 0.032; and for transfer of MMI: 0.165 +/- 0.025, 0.232 +/- 0.153, and 0.174 +/- 0.009 (for low doses without, low doses with, and high doses without albumin, respectively). Clearances of PTU from fetal to maternal circuits were: 0.147 +/- 0.072, 0.109 +/- 0.014, and 0.116 +/- 0.028; and for transfer of MMI: 0.095 +/- 0.029, 0.122 +/- 0.088, and 0.12 +/- 0.005 (in the same experiments). There was no significant difference between drugs or drug doses and no effect of addition of albumin. We conclude that PTU and MMI have similar placental transfer kinetics.
- Published
- 1997
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31. A comparison of Warner-Bratzler shear force assessment within and among institutions.
- Author
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Wheeler TL, Shackelford SD, Johnson LP, Miller MF, Miller RK, and Koohmaraie M
- Subjects
- Analysis of Variance, Animals, Calibration, Cattle, Food Handling instrumentation, Male, Reproducibility of Results, Statistics as Topic, United States, United States Department of Agriculture, Food Handling standards, Food Technology standards, Meat standards, Muscle, Skeletal physiology
- Abstract
Our objective was to compare measurement of Warner-Bratzler shear force of beef longissimus within and among institutions when each institution used its own protocol and when all institutions used a standardized protocol. In Exp. 1, each of five institutions (A, B, C, D, and E) received two adjacent steaks from each of 27 beef strip loins (longissimus lumborum). Warner-Bratzler shear force was measured for both steaks using the procedures normally used at each institution. In Exp. 2, each institution received two adjacent steaks from each of 45 strip loins. Shear force was measured for both steaks using a standardized protocol. In Exp. 1, Warner-Bratzler shear force was highest (P < .05) for A (4.7 kg) and lowest (P < .05) for B (2.9 kg). Repeatability of shear force was highest for A and C (.73 and .72), intermediate for D (.63), and lowest for B and E (.39 and .44). In Exp. 2, Warner-Bratzler shear force was highest (P < .05) for A (5.1 kg) and lowest (P < .05) for E (3.7 kg). Repeatability of shear force was highest for A (.87), intermediate for B, D, and E (.81, .75, and .80), and lowest for C (.67). Shear force values differed within and among institutions due to protocol, execution of the protocol, and instrument variation. Thus, comparisons of Warner-Bratzler shear force data among institutions are currently not valid. However, it is possible for institutions to obtain the same mean shear force value and have high repeatability if a standard protocol is properly executed with calibrated equipment.
- Published
- 1997
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32. Cortisol metabolism and its inhibition by glycyrrhetinic acid in the isolated perfused human placental lobule.
- Author
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Dodds HM, Taylor PJ, Johnson LP, Mortimer RH, Pond SM, and Cannell GR
- Subjects
- 11-beta-Hydroxysteroid Dehydrogenases, Administration, Topical, Chromatography, High Pressure Liquid, Female, Humans, Hydroxysteroid Dehydrogenases antagonists & inhibitors, Mass Spectrometry, Perfusion, Placenta metabolism, Anti-Inflammatory Agents metabolism, Anti-Inflammatory Agents pharmacology, Glycyrrhetinic Acid pharmacology, Hydrocortisone metabolism, Placenta drug effects
- Abstract
We have previously reported the placental metabolism of prednisolone to prednisone, 20alpha- and beta-dihydroprednisone and 20beta-dihydroprednisolone. In this study, the disposition of cortisol was investigated in vitro in the dual perfused, isolated human placental lobule after the addition of cortisol (1.2 micromol, n = 3 and 12 micromol, n = 4) to the maternal compartment. Analysis of 5 h maternal and fetal perfusate samples by high performance liquid chromatography-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS) revealed that cortisol was mainly metabolized to cortisone, but a significant production of 20alpha-dihydrocortisone, 20beta-dihydrocortisone, 20alpha-dihydrocortisol and 20beta-dihydrocortisol was also detected. Saturability of metabolism but not transfer was demonstrated. Metabolism was eliminated by co-perfusion with the potent 11beta-hydroxysteroid dehydrogenase (11beta-HSD) enzyme inhibitor 18beta-glycyrrhetinic acid (GA). The disposition of GA was analysed using HPLC-atmospheric pressure chemical ionisation-MS/MS (HPLC-APCI-MS/MS). GA was found to transfer from the maternal to the fetal circulations without detectable metabolism during 6 h of perfusion.
- Published
- 1997
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33. Intractable epistaxis: transantral ligation vs. embolization: efficacy review and cost analysis.
- Author
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Strong EB, Bell DA, Johnson LP, and Jacobs JM
- Subjects
- Adult, Aged, Aged, 80 and over, Costs and Cost Analysis, Female, Humans, Ligation economics, Male, Middle Aged, Postoperative Complications, Retrospective Studies, Risk Factors, Treatment Outcome, Embolization, Therapeutic economics, Epistaxis therapy, Maxillary Artery surgery
- Abstract
After posterior nasal packing, the two most common therapies for intractable epistaxis are transantral ligation of the internal maxillary artery and percutaneous embolization of the distal internal maxillary artery. However, optimal management of intractable posterior epistaxis remains controversial. We retrospectively reviewed the charts of 21 patients treated for intractable epistaxis and obtained data on presentation, risk factors, treatment, success rates, complications, and cost. Twelve patients received percutaneous embolization, five underwent transantral ligation, and four required both. The success rates for transantral ligation and percutaneous embolization were 89% and 94%, respectively. No mortality or serious morbidity occurred with either technique. A cost comparison revealed that transantral ligation was moderately less expensive than percutaneous embolization ($5941 vs. $6783). Although some authors advocate transantral ligation or percutaneous embolization as the procedure of choice for intractable epistaxis, a direct comparison of efficacy and cost reveals that they are comparable procedures with specific strengths and weaknesses. We present our experience and a review of the literature, highlighting the indications and advantages of each technique. We conclude that the choice of treatment modality should be based on the benefits of each procedure as it pertains to the specific needs of the individual patient.
- Published
- 1995
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34. A report of accidental ethylene glycol ingestion in 2 siblings.
- Author
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De Leacy EA, Moxon LN, Ellis VM, Van Dongen JM, Johnson LP, Doddrell DM, and Cowley DM
- Subjects
- Child, Preschool, Ethylene Glycol, Ethylene Glycols blood, Ethylene Glycols urine, Female, Humans, Male, Accidents, Home, Ethylene Glycols poisoning, Sibling Relations
- Abstract
We describe a case of 2 siblings aged 2 1/2 and 3 1/2 yrs accidentally poisoned by ethylene glycol ingestion. We found estimating the level of ethylene glycol in plasma by calculation of osmolar gap too insensitive to be of value and advocate the availability of a specific method. In our study only one of the 2 children had a toxic level of ethylene glycol but assay by conventional assay and by proton magnetic resonance spectroscopy (1HMRS) of toxic metabolites viz glycolate, glyoxylate and oxalate showed both to be excreting grossly elevated levels. This indicates the desirability of assaying the toxic metabolites of the glycol as well as the parent compound in assessing ingestions.
- Published
- 1995
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35. Leucine metabolism and body cell mass in cystic fibrosis.
- Author
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Shepherd RW, Holt TL, Johnson LP, Quirk P, and Thomas BJ
- Subjects
- Adolescent, Body Height physiology, Body Mass Index, Body Weight physiology, Carbon Isotopes, Child, Cystic Fibrosis complications, Cystic Fibrosis physiopathology, Female, Humans, Male, Nutrition Disorders etiology, Potassium metabolism, Reference Standards, Body Composition physiology, Cystic Fibrosis metabolism, Leucine metabolism, Nutrition Disorders metabolism
- Abstract
To further investigate the nature of malnutrition in cystic fibrosis (CF), specifically to evaluate the influence of body composition on leucine metabolism and determine whether measures used as reference standards alter comparative differences in protein metabolism, we measured [13C]leucine kinetics in nine well-nourished and eight malnourished, height-, FEV1-, and sex-matched CF subjects. Body cell mass was measured by total-body potassium (K40) analysis. Leucine turnover did not significantly differ between groups in absolute values or when corrected for body weight, body height, or surface area. However, malnourished CF patients had accelerated leucine turnover based on body cell mass measurements. Mean leucine synthesis per unit body cell mass in the malnourished group was 147% higher than that of the well-nourished group (p < 0.001). These data indicate that altered body composition is an important factor influencing protein metabolism in CF and should be considered in future metabolic studies. The importance of potentially serious but possibly correctable deficits in body cell mass in CF is emphasized.
- Published
- 1995
36. Foodservice industry market profile study: nutritional and objective textural profile of foodservice ground beef.
- Author
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Johnson LP, Williams SE, Neel SW, and Reagan JO
- Subjects
- Animals, Cattle, Cooking, Dietary Fats analysis, Fatty Acids analysis, Humans, Least-Squares Analysis, Meat analysis, Nutritive Value, United States, Food Services standards, Meat standards, Nutritional Physiological Phenomena
- Abstract
Ground beef patties of three types (regular, lean, extra-lean) destined for the foodservice industry were collected from foodservice purveyors in 12 cities equally distributed across six geographical regions of the United States to assess nutritional and objective texture characteristics. Patties were cooked on a foodservice-style clamshell grill to a well (approximately 80 degrees C) degree of doneness (internal temperature) for nutritional analysis and objective texture measurements. Single 5.08-cm2 samples were removed from the center of each patty and sheared with a multiple-blade Allo-Kramer shearing device. Nutritional composition, including proximate analysis values and fatty acid profiles, was determined on both raw and cooked samples of the ground beef. Extra-lean ground beef contained the least (P < .05) fat (12.43%), lean had an intermediate level (17.45%), and regular ground beef contained the most fat (P < .05) (20.20%), on a raw basis. However, after cooking, fat content was similar (P > .05) for regular and lean ground beef. Fatty acid composition of lipid and cholesterol content of ground beef did not differ (P > .05) across types of ground beef or between raw and cooked samples and was similar to USDA Handbook 8-13 values. Cooking loss decreased (P < .05) as fat percentages decreased. Regular and lean ground beef was easier (P < .05) to shear (4.20 and 4.24 kg/g of sample, respectively) than extra-lean ground beef (5.08 kg/g of sample). On average, foodservice ground beef sampled in the present study is 15.5% leaner than retail ground beef as presented in the National Beef Market Basket Survey and 22.2% leaner than USDA Handbook 8-13 values.
- Published
- 1994
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37. Calibration of albumin-fatty acid binding constants measured by heptane-water partition.
- Author
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Burczynski FJ, Pond SM, Davis CK, Johnson LP, and Weisiger RA
- Subjects
- Calibration, Chromatography, Thin Layer, Gas Chromatography-Mass Spectrometry, Methods, Palmitic Acid, Palmitic Acids isolation & purification, Reproducibility of Results, Time Factors, Fatty Acids metabolism, Heptanes, Serum Albumin metabolism, Water
- Abstract
Most measurements of binding affinity of albumin for long-chain fatty acids are based on heptane-water partition. In this method, equilibrium partition of fatty acid between heptane and an albumin-containing buffer is calibrated using the partition ratio between heptane and buffer in the absence of protein. In the current study, we used a variety of techniques to examine potential problems with this approach. Hydrophobic impurities in commercial [3H]palmitate preparations were incompletely removed by standard purification techniques. These impurities contributed from 5% of the total radioactivity in the heptane phase at low albumin concentrations (5 microM) to 62% at higher albumin concentrations (500 microM), thus confounding determination of binding affinity. These were identified by gas chromatography/mass spectroscopy as radio-labeled glycerol monopalmitate and monostearate. When albumin was not present, the partition ratio was similar to values reported by others. However, our results varied by a factor of four (265-1,119) depending on how the solutions were prepared. Although a true equilibrium partition must not depend on starting conditions, the partition ratio after 24-72 h was > 2x as large when tracer [3H]palmitate was added to the heptane phase than when it was added to the aqueous phase. Results also depended on the relative volumes of heptane and buffer used, approaching a maximum of 1,445 +/- 112 for very low heptane/buffer volume ratios. Much of this variability was due to hydrophilic impurities in [3H]palmitate, which ranged from 0.2 to 1.2% in commercial lots down to 0.1-0.5% after alkaline ethanol extraction and < 0.05% after thin-layer chromatography (TLC).(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
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38. Foodservice industry market profile study: in-plant beef fat trim level survey and cutting yields.
- Author
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Neel SW, Williams SE, Johnson LP, Gwartney BL, and Reagan JO
- Subjects
- Adipose Tissue, Animals, Cattle, Consumer Behavior, Food Services trends, Food-Processing Industry trends, Nutritive Value, Dietary Fats, Food Handling, Food Services standards, Food-Processing Industry standards, Meat standards
- Abstract
Fifty foodservice purveying companies were sampled in 12 U.S. cities evenly distributed across six geographical regions. Beef whole muscle cuts (WMC) and portion control items (PCI) from the primal rib and loin were evaluated for surface fat levels. Fat thicknesses were measured on WMC before and after fabrication, whereas additional PCI were measured for fat trim levels before distribution. The average initial fat thickness was 11.9 mm (174 Short Loin and 180A Strip Loin) and 15.6 mm (184 Top Sirloin Butt); maximum fat thicknesses ranged from 16.2 mm (strip loin) to 22.2 mm (top sirloin butt). After fabrication, average fat thicknesses were 6.2, 5.1, and 4.0 mm for resulting products from the short loin, strip loin, and top sirloin butt, respectively. The average initial fat thickness for the strip loin was greater (P < .05) in Southeast and Northeast regions than in Mountain/Desert, Midwest, and Southwest regions. In contrast, average trimmed fat thicknesses for products from the strip loin and top sirloin butt were lower (P < .05) in the Southeast and Northeast than in all other regions. Average fat trim levels for PCI were 3.0 (1112A Ribeye Roll steak, Lip-On), 5.3 (1173B/1174B T-Bone/Porterhouse steak), 5.0 (1180A Strip Loin steak), and 4.0 mm (1184B Top Sirloin steak). Maximum fat trim levels were 4.4 (IMPS 1112A), 7.4 (IMPS 1173B/1174B), 6.9 (IMPS 1180A), and 5.5 mm (IMPS 1184B). The PCI had average and maximum fat trim levels in compliance with USDA (1988) recommendations for fat trim specifications.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
- Full Text
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39. Extending the limits of lung cancer resection.
- Author
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Aye RW, Mate TP, Anderson HN, Johnson LP, and Hill L
- Subjects
- Brachytherapy adverse effects, Carcinoma, Bronchogenic surgery, Chondrosarcoma radiotherapy, Chondrosarcoma secondary, Chondrosarcoma surgery, Combined Modality Therapy, Follow-Up Studies, Humans, Intraoperative Period, Iodine Radioisotopes therapeutic use, Iridium Radioisotopes therapeutic use, Lung Neoplasms secondary, Lung Neoplasms surgery, Neoplasm Recurrence, Local, Postoperative Care, Radiotherapy Dosage, Brachytherapy methods, Carcinoma, Bronchogenic radiotherapy, Lung Neoplasms radiotherapy
- Abstract
Patients with locally advanced bronchogenic carcinoma are often considered to have unresectable disease because of invasion into vital structures, or they undergo resection with questionable or involved margins, which results in local recurrence later. Brachytherapy (direct application of radioactive sources to the tumor bed) offers the potential to provide tumoricidal doses of radiation to the target area with minimal toxicity to surrounding structures. In this study, one of two different techniques of brachytherapy was utilized to treat 15 highly selected patients with histologically positive (n = 8) or suspicious (n = 7) margins after resection. The techniques were easy to apply and were not associated with any complications directly related to their use. One postoperative death resulted from a perforated peptic ulcer. In the remaining 14 patients, at a mean follow-up of 38 months, local control was complete in 12 (86%) patients, and 8 patients are alive, with 7 free of disease. Thoracic brachytherapy may offer the potential for cure to patients whose disease would otherwise be considered inoperable.
- Published
- 1993
- Full Text
- View/download PDF
40. Shielding at the egress of a 23 mV linear accelerator.
- Author
-
Trappier AS and Johnson LP
- Subjects
- Biophysical Phenomena, Biophysics, Equipment Design, Radiation Dosage, Neutrons, Particle Accelerators, Radiation Protection methods, Radiotherapy instrumentation
- Abstract
Radiation shielding is required in radiotherapy accelerators to limit the dose equivalent rate from x-rays produced at the target in all directions except that of the useful forward directed beam. Calculations were made in terms of weekly workload of 50,000 cGy delivered to the isocenter per 5-day week, treating 25 patients per day at 400 cGy per patient. It is desirable to reduce the total exposure at the maze door below 30 Rem (0.30 Sv)/wk assuming full-time occupancy. The maze was designed to reduce the neutron dose to an acceptable level by slowing the neutrons to thermal velocities and then absorbing them in a low Z material in the egress.
- Published
- 1993
41. Effect of hot-fat trimming on factors associated with the subprimal yield of beef carcasses.
- Author
-
Ahmed PO, Miller MF, Shackelford SD, Johnson LP, Williams SE, McCann MA, and Reagan JO
- Subjects
- Animals, Female, Male, Regression Analysis, Sex Characteristics, Ultrasonography, Adipose Tissue diagnostic imaging, Cattle anatomy & histology, Food Handling methods, Meat standards
- Abstract
Thirty-two crossbred cattle (steers = 17; heifers = 15) exhibiting an ultrasound fat thickness at the 12 to 13th rib region of at least 10 mm were selected from a slaughter shift at a commercial packing plant. After splitting, alternating sides of each carcass were trimmed of 1) subcutaneous fat in excess of 6.4 mm; 2) all kidney, pelvic, and heart fat; and 3) all cod or udder fat and fat in the flank region. Both sides of each carcass were fabricated into subprimals (final trim level of 6.4 mm) according to normal industry procedures. Effect of hot-fat trimming, yield grade (3, 4, and 5), and gender on hot-fat trim, fabrication fat trim, major subprimal, and total subprimal yield of untrimmed and trimmed carcasses were determined. Higher numerical yield grade (YG) corresponded with higher (P less than .05) percentages of hot-fat trim. Hot-fat trimming increased (P less than .05) the difference in fabrication fat trim between steers and heifers and between YG 3 and YG 5. Steers and heifers differed (P less than .05) in percentage of major subprimals and total subprimals when processed conventionally, whereas hot-fat trimming eliminated this difference (P less than .05). Untrimmed YG 3 carcasses had 3.1 and 5.0% higher major subprimal yield (P less than .05) than untrimmed YG 4 and YG 5 carcasses, respectively, whereas hot-fat trimming reduced this difference to 2.5% for YG 4 and to 3.7% for YG 5.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1992
- Full Text
- View/download PDF
42. Selective management of early glottic cancer.
- Author
-
Davis RK, Kelly SM, Parkin JL, Stevens MH, and Johnson LP
- Subjects
- Adult, Aged, Aged, 80 and over, Combined Modality Therapy, Female, Humans, Laryngeal Neoplasms pathology, Male, Middle Aged, Glottis, Laryngeal Neoplasms therapy
- Abstract
Seventy patients with stage I and II glottic cancer were treated at the University of Utah School of Medicine hospitals from 1980 through 1987. Forty-four patients had stage I cancer and 26 patients had stage II. The overall survival in the stage I group was 82%. Primary site control was 93% with only three deaths due to laryngeal cancer. Local control rates were 93% with CO2 laser excision, 80% with CO2 laser and irradiation, and 67% with radiation alone. Stage II glottic patients had an overall survival of 61.5% with a local control rate of 76%. Twenty-one of 24 patients were treated by full-course irradiation. Of the eight patients who recurred at the primary site, all were irradiation failures who had initial bulky disease and impaired vocal cord mobility. Selective CO2 laser excision was highly effective, whereas radiation therapy results were somewhat disappointing. Open partial laryngectomy should be considered in bulky stage II disease patients.
- Published
- 1990
- Full Text
- View/download PDF
43. The prediction of percentage of fat in pork carcasses.
- Author
-
Johnson LP, Miller MF, Haydon KD, and Reagan JO
- Subjects
- Adipose Tissue chemistry, Animals, Bone and Bones chemistry, Female, Male, Muscles chemistry, Regression Analysis, Skin chemistry, Specific Gravity, Swine, Lipids analysis, Meat analysis
- Abstract
Forty-seven market-weight pigs were slaughtered in order to determine percentage of chemical fat and in an attempt to determine an easily obtainable and inexpensive method to predict this value. The hams and 8-9-10 rib loin sections were removed from the left side of each carcass and dissected into subcutaneous and seam fat, individual muscles, skin and bone. Weights and chemical analysis were determined for each component. Numerous weights, measurements and specific gravity were determined on the carcass, ham and loin section of each pig. Percentage of chemical fat of each ham, loin section and carcasses was determined and correlated with the various weights and measurements taken. Stepwise regression was used to develop prediction equations using carcass data, specific gravity, ham or loin measurements or various combinations of these as dependent variables. The single best indicator of the decimal fraction of chemical fat in the pork carcass was determined to be specific gravity of the carcass half, the prediction equation using this variable had an R-square of .64. By adding 10th rib fat thickness to this equation, the R-square increased to .72. The best equation using carcass variables included 10th rib fat and marbling (R-square = .67). The loin section proved to be an accurate indicator of composition; ham measures were not as accurate as specific gravity and carcass measurements for predicting percentage of carcass fat. This research suggests that the percentage of chemical fat in the pork carcass can be predicted by an easy and inexpensive means.
- Published
- 1990
- Full Text
- View/download PDF
44. The prediction of percentage of protein in pork carcasses.
- Author
-
Johnson LP, Reagan JO, Haydon KD, and Miller MF
- Subjects
- Adipose Tissue chemistry, Animals, Bone and Bones chemistry, Female, Male, Muscles chemistry, Skin chemistry, Specific Gravity, Swine, Meat analysis, Proteins analysis
- Abstract
Determination of percentage of protein in a pork carcass is a very costly and lengthy process. Therefore, we attempted to identify an easy and economical means to predict protein content of pork carcasses. Forty-seven market-weight pigs were slaughtered. The right side of each carcass was skinned, deboned and ground for composition analysis. Carcass data were collected on the left side and specific gravity analysis was performed on the side, ham and 8-9-10 rib loin section of each carcass. The hams and loin sections were dissected into skin, bone, subcutaneous fat, seam fat and individual muscles. After these components were weighted, they were analyzed for chemical composition. Percentage of chemical protein of each animal was determined and correlated with each of the weights and measurements taken on the carcass, ham and loin sections. Stepwise regression was used to predict decimal fraction of protein using either the carcass data, specific gravity ham measurements, loin section measurements or various combinations of these. In prediction equation, specific gravity of the carcass accounted for 73.4% of the variation found in percentage of protein. Prediction equations using indicators from the ham and loin section resulted in equations with R-square values as high as .783. These results suggest that specific gravity or indicators from the carcass, ham or loin section can be employed to predict percentage of protein in pork carcasses.
- Published
- 1990
- Full Text
- View/download PDF
45. Evolving perspectives on the exposure risks from magnetic fields.
- Author
-
Trappier A, Lorio P, and Johnson LP
- Subjects
- Health Workforce, Humans, In Vitro Techniques, Lung Neoplasms pathology, Risk Factors, Tumor Cells, Cultured radiation effects, Electromagnetic Fields, Magnetic Resonance Imaging instrumentation, Occupational Exposure
- Abstract
Based on information from suggesting effects of positive and negative polarity on cancer cells, surveys were performed on magnetic resonance imaging devices, as well as other types of equipment capable of producing appreciable magnetic fields. These surveys were performed in areas where there was a potential for both occupational and general public exposure.
- Published
- 1990
46. Computer assisted linear accelerator shielding calculations.
- Author
-
Trappier AS and Johnson LP
- Subjects
- Humans, Information Systems, Mathematical Computing, Particle Accelerators, Radiation Protection
- Published
- 1990
47. Paranasal sinus applications of surgical lasers.
- Author
-
Johnson LP
- Subjects
- Humans, Laser Therapy, Paranasal Sinus Diseases surgery
- Abstract
This review presents uses of surgical lasers in the treatment of paranasal sinus disease. The author also discusses briefly the applications of lasers that require further investigation.
- Published
- 1990
48. Group A streptococcal phage T12 carries the structural gene for pyrogenic exotoxin type A.
- Author
-
Johnson LP and Schlievert PM
- Subjects
- Animals, Bacterial Toxins toxicity, Cloning, Molecular, Escherichia coli genetics, Genes, Genes, Viral, Lymphocyte Activation, Mice, Rabbits, Shock, Septic chemically induced, Bacterial Proteins, Bacterial Toxins genetics, Bacteriophages genetics, Exotoxins, Membrane Proteins, Streptococcus pyogenes genetics
- Abstract
The structural gene for group A streptococcal pyrogenic exotoxin (SPE) type A was cloned into E. coli. DNA fragments used for cloning the toxin gene were isolated from bacteriophage T12. Toxin, present in cell lysates of E. coli clones, immunoprecipitated with antisera raised against purified SPE type A and formed a line of identity with streptococcal-derived A toxin. The cloned toxin shared the following biological activities with streptococcal A toxin: Pyrogenicity; enhancement of host susceptibility to lethal endotoxin shock; nonspecific lymphocyte mitogenicity; and alteration of immunoglobulin production. The physical location of the toxin gene on the phage T12 genome was determined.
- Published
- 1984
- Full Text
- View/download PDF
49. Mesothelioma: current perspectives.
- Author
-
Taylor RA and Johnson LP
- Subjects
- Asbestos adverse effects, Female, Humans, Male, Mesothelioma epidemiology, Mesothelioma etiology, Middle Aged, Peritoneal Neoplasms epidemiology, Peritoneal Neoplasms etiology, Pleural Neoplasms epidemiology, Pleural Neoplasms etiology, Washington, Mesothelioma diagnosis, Peritoneal Neoplasms diagnosis, Pleural Neoplasms diagnosis
- Abstract
Thirty patients with the diagnosis of mesothelioma were admitted to the Swedish Hospital Medical Center, Seattle, from 1975 to 1979. Of these, 26 had pleural and 4 had peritoneal mesothelioma. In 20 of the patients with pleural mesothelioma, the diagnosis had been made by open thoractomy and in only one by needle biopsy of the pleura. The average survival of the patients with pleural tumors from time of diagnosis was 15 months, and two are alive at three and eight months, respectively, one of whom had an apparent solitary benign mesothelioma. The average survival of those with peritoneal mesothelioma was ten months, although one has survived six years. There were 17 patients with a known history of exposure to asbestos, 14 while working in shipyards. Because of the relatively high incidence of this previously rare tumor in the Puget Sound, Washington, area, and the generally dismal results of therapy, better methods of diagnosis including thoracoscopy and a more systematic approach to treatment are recommended.
- Published
- 1981
50. Transtympanic eustachian tuboplasty and tolerance of stenting materials.
- Author
-
Parkin JL, Johnson LP, and Stringham JC
- Subjects
- Animals, Biocompatible Materials, Cats, Foreign-Body Reaction, Polyethylenes, Polyurethanes, Postoperative Period, Silicone Elastomers, Eustachian Tube surgery, Middle Ear Ventilation methods, Prostheses and Implants adverse effects
- Abstract
The purpose of this study was to evaluate various eustachian tube stenting materials in an attempt to develop a successful transtympanic eustachian tuboplasty technique. Eustachian tube mucosa was removed transtympanically in 40 feline ears. Ten ears were used as controls. Polyethylene, Silastic, and polyurethane stents were placed in 30 ears, 10 ears with each material. The ears were evaluated after a minimum of 8 weeks and the stents were removed. Eight weeks after stent removal the ears were assessed visually, tympanometrically, and by biopsies of the osseous eustachian tube mucosa. Inadequate middle ear ventilation as evidenced by persistent otitis media, persistent tympanic membrane perforations, or type B or type C tympanograms was found in 60% of control, 30% of Silastic-stented, 60% of polyurethane-stented, and 0% of polyethylene-stented ears. Small polyethylene stents were most successful in reestablishing eustachian tube function in this experiment.
- Published
- 1983
- Full Text
- View/download PDF
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