Publications by authors named "Stith J"

Sphingosine kinase 1 (SK1) is a key sphingolipid enzyme that is upregulated in several types of cancer, including lymphoma which is a heterogenous group of malignancies. Treatment for lymphoma has improved significantly by the introduction of new therapies; however, subtypes with tumor protein P53 (p53) mutations or deletion have poor prognosis, making it critical to explore new therapeutic strategies in this context. SK1 has been proposed as a therapeutic target in different types of cancer; however, the effect of targeting SK1 in cancers with p53 deletion has not been evaluated yet.

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Article Synopsis
  • Senescence is a natural process that stops cells from growing, which helps prevent tumors; certain genes like K-Ras can cause this process in cells.* -
  • In a study with specific cells, scientists found that K-Ras increases certain chemicals called ceramides and affects a protein called sphingosine kinase 1 (SK1), which plays a role in cell growth.* -
  • By lowering levels of SK1, the scientists were able to increase signs of senescence and stop cell growth, suggesting that targeting SK1 could be a new way to treat cancer.*
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Objectives/hypothesis: The purpose of this study is to develop consensus on key points that would support the use of systemic bevacizumab for the treatment of recurrent respiratory papillomatosis (RRP), and to provide preliminary guidance surrounding the use of this treatment modality.

Study Design: Delphi method-based survey series.

Methods: A multidisciplinary, multi-institutional panel of physicians with experience using systemic bevacizumab for the treatment of RRP was established.

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Sphingolipids and their synthetic enzymes have emerged as critical mediators in numerous diseases including inflammation, aging, and cancer. One enzyme in particular, sphingosine kinase (SK) and its product sphingosine-1-phosphate (S1P), has been extensively implicated in these processes. SK catalyzes the phosphorylation of sphingosine to S1P and exists as two isoforms, SK1 and SK2.

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Ceramide is a critical bioactive lipid involved in diverse cellular processes. It has been proposed to regulate cellular processes by influencing membrane properties and by directly interacting with effector proteins. Advances over the past decade have improved our understanding of ceramide as a bioactive lipid.

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While bones and muscles adapt to mechanical loading, it appears that very specific types of stimuli must be applied to achieve osteogenesis. Our study assessed musculoskeletal outcomes to 30 training sessions on an Inertial Exercise Trainer (Newnan, GA). Subjects (n=13) performed workouts with their left leg, while their right served as an untreated control.

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Unlabelled: The purpose of this study determined if oral supplementation of Protandim® (a nutraceutical) for 90 days improved 5-km running performance and reduced serum thiobarbituric acid-reacting substances (TBARS) at rest, an indicator of oxidative stress. Secondary objectives were to measure whole blood superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPX), at rest and 10 minutes after completion of the race before and after supplementation as well as quality of life. In a double-blind, randomized, placebo controlled trial, 38 runners [mean (SD) = 34 (7) yrs; BMI = 22 (2) kg/m2] received either 90 days of Protandim® [1 pill a day, n = 19)] or placebo (n = 19).

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Optical properties and precipitation efficiency of atmospheric clouds are largely determined by turbulent mixing with their environment. When cloud liquid water is reduced upon mixing, droplets may evaporate uniformly across the population or, in the other extreme, a subset of droplets may evaporate completely, leaving the remaining drops unaffected. Here, we use airborne holographic imaging to visualize the spatial structure and droplet size distribution at the smallest turbulent scales, thereby observing their response to entrainment and mixing with clear air.

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Background And Purpose: Postural vertical refers to a component of an individual's perception of verticality that is derived from information about the direction of gravitational forces. Backward disequilibrium (BD) is a postural disorder observed in some older adults who have a distortion in their perception of postural vertical. Individuals with BD sustain their center of mass (COM) posterior to their base of support and resist correction of COM alignment.

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Effects on the slope of introducing error in the F2 Hz values in locus equations (LEs) and of using fewer than ten vowels were investigated. For each of the initial consonants /b, d, g/, 2000 simulated sets were generated using Monte Carlo techniques. The sets were altered with 50, 100, or 200 Hz error being randomly applied to each F2 value within a set.

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Numerous studies are demonstrating that engaging undergraduate students in original research can improve their achievement in the science, technology, engineering, and mathematics (STEM) fields and increase the likelihood that some of them will decide to pursue careers in these disciplines. Associated with this increased prominence of research in the undergraduate curriculum are greater expectations from funders, colleges, and universities that faculty mentors will help those students, along with their graduate students and postdoctoral fellows, develop an understanding and sense of personal and collective obligation for responsible conduct of science (RCS). This Feature describes an ongoing National Research Council (NRC) project and a recent report about educating faculty members in culturally diverse settings (Middle East/North Africa and Asia) to employ active-learning strategies to engage their students and colleagues deeply in issues related to RCS.

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In the lowermost layer of the atmosphere-the troposphere-ozone is an important source of the hydroxyl radical, an oxidant that breaks down most pollutants and some greenhouse gases. High concentrations of tropospheric ozone are toxic, however, and have a detrimental effect on human health and ecosystem productivity. Moreover, tropospheric ozone itself acts as an effective greenhouse gas.

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Background And Purpose: Understanding the factors that contribute to student satisfaction may lead to improved education in physical therapy. This study tested the extent to which variables in the personal, interpersonal, and organizational domains influence satisfaction with clinical experiences.

Subjects: Physical therapist students (N = 113) in 2 phases of their clinical experiences at one private school participated.

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Among 145 patients treated with recombinant human growth hormone (GH), four developed sleep apnea (two obstructive, two mixed) associated with tonsillar and adenoidal hypertrophy in three. These four patients had no local risk factors predisposing to upper airway obstruction (i.e.

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We report the MR results of four patients with plexiform neurofibromas of the larynx. Three had irregular margins and were circumferential around the airway. The distinction between regularly and irregularly shaped neurofibromas may have implications for symptom onset.

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The all-night polysomnographic findings of nine patients with spastic quadriparesis (mean age 36.7 months) were analysed retrospectively and compared with those of nine age-matched controls (mean age 37.4 months).

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Paranasal and nasal neoplasms often elude early diagnosis in the pediatric population. This report examines 3 cases of nasal and paranasal sinus lymphomas out of 29 lymphomas and lymphoproliferative disorders seen from 1983 to 1990. Diagnostic delays are common.

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