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Dive into the research topics where Michael M. Johns is active.

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Featured researches published by Michael M. Johns.


Current Opinion in Otolaryngology & Head and Neck Surgery | 2003

Update on the etiology, diagnosis, and treatment of vocal fold nodules, polyps, and cysts.

Michael M. Johns

Purpose of reviewInnovative otolaryngologists, speech language pathologists, and voice scientists have continued to advance our understanding of the etiology, diagnosis, and treatment of vocal fold nodules, polyps, and cysts. This article reviews the recent publications over the past 3 years with respect to these advances. Recent findingsSupport for the notion that benign vocal fold lesions arise from phonatory trauma and vocal misuse continues to become evident. Changes in the molecular characteristics of the lamina propria in these lesions are beginning to be understood. For diagnostic purposes, the use of innovative technology such as ultrasonography and virtual laryngoscopy is being explored. Continued support for behavior modification as a primary treatment modality for benign vocal fold lesions has been published, and refinements in technical aspects of laryngeal microsurgery persist. Finally, outcomes studies have demonstrated improvements in vocal disability with both behavioral and surgical interventions. SummaryClinical and basic research has furthered our understanding of benign vocal fold lesions and has expanded our diagnostic and therapeutic armamentarium for patients with dysphonia arising from these lesions.


Circulation Research | 2012

Activating Transcription Factor 1 Directs Mhem Atheroprotective Macrophages Through Coordinated Iron Handling and Foam Cell Protection

Joseph J. Boyle; Michael M. Johns; Theresa Kampfer; Aivi T. Nguyen; Laurence Game; Dominik J. Schaer; Justin C. Mason; Dorian O. Haskard

Rationale: Intraplaque hemorrhage (IPH) drives atherosclerosis through the dual metabolic stresses of cholesterol-enriched erythrocyte membranes and pro-oxidant heme/iron. When clearing tissue hemorrhage, macrophages are typically seen storing either iron or lipid. We have recently defined hemorrhage-associated macrophages (HA-mac) as a plaque macrophage population that responds adaptively to IPH. Objective: This study aimed to define the key transcription factor(s) involved in HO-1 induction by heme. Methods and Results: To address this question, we used microarray analysis and transfection with siRNA and plasmids. To maintain physiological relevance, we focused on human blood-derived monocytes. We found that heme stimulates monocytes through induction of activating transcription factor 1 (ATF-1). ATF-1 coinduces heme oxygenase-1 (HO-1) and Liver X receptor beta (LXR-&bgr;). Heme-induced HO-1 and LXR-&bgr; were suppressed by knockdown of ATF-1, and HO-1 and LXR-&bgr; were induced by ATF-1 transfection. ATF-1 required phosphorylation for full functional activity. Expression of LXR-&bgr; in turn led to induction of other genes central to cholesterol efflux, such as LXR-&agr; and ABCA1. This heme-directed state was distinct from known macrophage states (M1, M2, Mox) and, following the same format, we have designated them Mhem. Conclusions: These results show that ATF-1 mediates HO-1 induction by heme and drives macrophage adaptation to intraplaque hemorrhage. Our definition of an ATF-1–mediated pathway for linked protection from foam cell formation and oxidant stress may have therapeutic potential.


Journal of the American Geriatrics Society | 2006

Prevalence of Perceived Dysphonia in a Geriatric Population

Justin S. Golub; Po Hung Chen; Kristen J. Otto; Edie R. Hapner; Michael M. Johns

OBJECTIVES: To characterize geriatric dysphonia, including its prevalence, quality‐of‐life impairment, and association with overall health status.


Academic Medicine | 2007

Burnout in Residents of Otolaryngology–head and Neck Surgery: A National Inquiry into the Health of Residency Training

Justin S. Golub; Paul S. Weiss; Atul K. Ramesh; Robert H. Ossoff; Michael M. Johns

Purpose To characterize resident burnout on a national scale with a large sample size and to identify associated modifiable factors to minimize burnout and improve the quality of residency education. Method A survey was mailed to all 1,364 U.S. residents of otolaryngology–head and neck surgery in September 2005. The main outcome measures were the Maslach Burnout Inventory–Human Services Study, demographic information, and potential burnout predictors, including stressors, satisfaction, self-efficacy, and support systems. Results The response rate was 50% (684/1,364). Current second-year through fifth-year residents were included for further analysis (514). Burnout was extremely common among otolaryngology residents. High burnout was seen in 10% of residents (51), moderate burnout in 76% (391), and low burnout in 14% (72). The strongest associated demographic factor was work hours (P < .001). Hours worked was predictive of emotional exhaustion, with exhaustion scores rising by 0.19 for each hour worked (P < .001). Furthermore, there was an 8% (41 resident) reported violation rate of the Accreditation Council for Graduate Medical Education (ACGME) 80-hour-workweek limitation. Satisfaction with the balance between personal and professional life, relationship stability, and satisfaction with career choice were negatively associated with burnout (all P < .001). Conclusions Burnout is widely prevalent among U.S. otolaryngology residents and is present at greater levels than those seen in chairs or faculty of the same specialty. Work hours predict emotional exhaustion, and adherence to the ACGME 80-hour workweek may help protect against burnout and its deleterious consequences in residents of all specialties.


Laryngoscope | 2009

Advances in office-based diagnosis and treatment in laryngology.

Clark A. Rosen; Milan R. Amin; Lucian Sulica; C. Blake Simpson; Albert L. Merati; Mark S. Courey; Michael M. Johns; Gregory N. Postma

No abtracts.


Laryngoscope | 2005

Burnout in Academic Chairs of Otolaryngology: Head and Neck Surgery

Michael M. Johns; Robert H. Ossoff

Background: Burnout can be characterized by a low degree of personal accomplishment and a high degree of emotional exhaustion and depersonalization using the Maslach Burnout Inventory–Human Services Survey (MBI‐HSS). With increasing demands and constraints placed on academic department chairs, the risk of developing burnout may be increasing. The prevalence of burnout in chairs of academic departments of otolaryngology and the factors associated with it have not been previously described.


Journal of Voice | 2009

A study of voice therapy dropout.

Edie R. Hapner; Carissa Portone-Maira; Michael M. Johns

Treatment dropout is a consistent problem among behavior change therapies. A recent study by the authors demonstrated that 38% of patients did not attend a voice evaluation after referral by the otolaryngologist. Further, 47% of patients who attended a voice evaluation did not return for therapy. No previous study has set out to document completion/dropout rates for voice therapy, but high rates of attrition are reported as problematic within voice therapy research studies. The purpose of this study was to quantify the problem of voice therapy dropout over the course of voice therapy and to analyze factors that may predict dropout using a retrospective chart review. Data were collected at two voice centers and included demographics (gender, age, and race/ethnicity), quality-of-life impact (Voice Handicap Index [VHI]), severity of dysphonia (Consensus Auditory Perceptual Evaluation of Voice [CAPE-V] overall severity score), diagnosis, and completion/dropout status. Results indicated a 65% voice therapy dropout rate in this study. There was no significant difference in dropout rates for gender, age, race, VHI, CAPE-V, or diagnosis. No factor studied was strongly associated with dropout. The 65% dropout rate in this study was consistent with literature published in other behavior change fields. The variables analyzed in this study were not predictive of dropout. Future research should examine methods to effect a reduction in dropout, from otolaryngologist referral through completion of therapy.


Journal of Clinical Oncology | 2010

Prognostic Accuracy of Computed Tomography Findings for Patients With Laryngeal Cancer Undergoing Laryngectomy

Jonathan J. Beitler; Susan Muller; William Grist; Amanda S. Corey; Adam M. Klein; Michael M. Johns; Charles Perkins; Lawrence W. Davis; Unni Udayasanker; Jerome C. Landry; Dong M. Shin; Patricia A. Hudgins

PURPOSE The indications for upfront laryngectomy in the management of laryngeal cancer are a functionless larynx and extralaryngeal extension. Practically, clinicians rely on imaging to predict which patients will have T4 disease. Our goal was to review the accuracy of preoperative computed tomography (CT) scanning in determining the necessity for initial laryngectomy for advanced laryngeal cancer. PATIENTS AND METHODS In total, 107 consecutive untreated laryngectomy specimens with high-quality, preoperative CT imaging interpreted by our neuroradiologists were reviewed. Radiographic findings, including sclerosis, invasion, penetration, extralaryngeal spread, and subglottic extension were correlated with pathologic findings. CT images were not reinterpreted, since our purpose was to assess the original interpretations. RESULTS CT imaging reported 23 cases of thyroid cartilage penetration and 27 cases of extralaryngeal spread. Pathology reported 12 cases of thyroid cartilage invasion, 29 cases of penetration, and 45 cases of extralaryngeal disease. CT imaging identified 17 (59%) of 29 cases of pathologically documented thyroid cartilage penetration and 22 (49%) of 45 cases of pathologically documented extralaryngeal spread. Pathologically proven extralaryngeal spread without thyroid cartilage penetration occurred in 18 (40%) of 45 cases. The positive predictive values for thyroid cartilage penetration and extralaryngeal spread were 74% and 81%. Sclerosis was of limited value in predicting thyroid cartilage invasion or penetration. Cricoid or arytenoid destruction predicted for thyroid cartilage penetration at rates of 57% and 63%. CONCLUSION CT imaging has clear limitations when deciding whether there is thyroid cartilage penetration or extralaryngeal spread of advanced laryngeal cancer. Extralaryngeal spread without thyroid cartilage penetration was more common than expected. Alternate methods of pretreatment assessment are needed.


Journal of Immunological Methods | 2000

In vivo selection of sFv from phage display libraries

Michael M. Johns; Andrew J. T. George; Mary A. Ritter

The development of phage display technology has facilitated the development of many new and sometimes novel antibody based reagents for scientific research. However, present methods for selection from phage-sFv display libraries are limited to selection against purified antigens or ex vivo cells of known origin and phenotype. Existing methods therefore preclude the isolation of sFv against unknown molecules in their natural environment, where expression is complex and subject to diverse control mechanisms. Since such a complex environment is difficult to mimic in vitro, the development of an in vivo selection procedure would greatly enhance the selection from phage display antibody libraries and lead to the development of reagents against cell surface molecules in their natural environment. This would be particularly advantageous for isolation of sFv against vascular endothelium which can readily change phenotype when cultured and is believed to express molecules in a tissue specific manner and in response to different stimuli. We describe here the development of an in vivo selection procedure in the mouse and demonstrate its potential for the selection of sFv from a phage-sFv library. The target antigen for one sFv is expressed solely on the thymic endothelium, while the second, a 165-170 kDa molecule in present on both thymic endothelium and the perivascular epithelium.


Laryngoscope | 2011

Current dysphonia trends in patients over the age of 65; Is vocal atrophy becoming more prevalent?

Taryn Davids; Adam M. Klein; Michael M. Johns

The current trends in geriatric voice referrals including the number of patients over the age of 65 years seen per year, the common diagnostic patterns, and specifically the number of patients with vocal atrophy were assessed.

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Dorian O. Haskard

National Institutes of Health

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Cheryl Ulmer

United States Department of Health and Human Services

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Justin C. Mason

National Institutes of Health

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