Ken Y Yoneda

California State University, Sacramento, Sacramento, California, United States

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Publications (31)116.07 Total impact

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    ABSTRACT: Background: Airway obstruction from blood clots, airway secretions, and foreign bodies is a potentially life-threatening condition. Optimal management of this problem, whether by rigid or flexible bronchoscopy, has not been well studied. We report our single-center experience on the safety and clinical utility of cryoprobe extraction for this indication. Methods: We performed a retrospective chart review from January 2006 to November 2014 of all subjects aged 18 and older who underwent flexible bronchoscopic cryoprobe extraction. Subjects with obstruction due to benign or malignant neoplasm or airway stenosis were excluded. Results: A total of 38 cryotherapy sessions performed on 30 subjects were identified for inclusion. Cryoprobe extraction was successful in reestablishing airway patency in 32/38 (84%) sessions overall and in 24/26 (92%) for blood clots, 4/6 (67%) for mucous plugging, 2/4 (50%) for foreign bodies, and 2/2 (100%) for plastic bronchitis. Twenty-one of 31 (68%) sessions resulted in improvement in oxygenation or ventilation. There was 1 complication related to sedation. Conclusions: We conclude that flexible bronchoscopic cryoprobe extraction of blood clots, mucous secretions, plastic bronchitis, and foreign bodies is a safe and effective option. It can be safely performed at the bedside and in many cases eliminates the need for rigid bronchoscopy.
    No preview · Article · Oct 2015 · Journal of Investigative Medicine
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    Sassan Rafizadeh · Ken Yoneda · Amir A Zeki
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    ABSTRACT: We report a patient with tracheopathia osteoplastica (TPO), a rare or perhaps underrecognized disorder, detected in approximately 1 in every 2000 to 5000 patients who undergo bronchoscopy. TPO is marked by proliferation of bony and cartilaginous spurs leading to airway stenosis. Multiple submucosal cartilaginous and osseous nodules can develop in the respiratory tract and may involve the entire trachea and mainstem bronchi. Symptoms may range from a completely silent condition to life-threatening respiratory failure and diagnosis is made based on radiological and bronchoscopic findings. Although the etiology has not been established, TPO can be familial and is sometimes associated with chronic inflammation, such as seen with rheumatic diseases. This case highlights the need for understanding TPO so that it can be differentiated from potentially serious conditions such as necrotizing granulomatous diseases, invasive infections, and cancer.
    Full-text · Article · Jun 2015
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    ABSTRACT: Kyphoscoliosis is known to compromise lung function, with the primary mechanism being reduced chest wall compliance with a resultant restrictive pulmonary physiology. Severe scoliosis can also cause extrinsic compression of the central airways, leading to recurrent respiratory infections, lobar atelectasis, and potentially acute respiratory failure. Definitive therapy is corrective surgery of the spine. However, patients with severe scoliosis are at a potentially high risk of perioperative pulmonary complications. To our knowledge, we report the first successful use of retrievable endobronchial stents as a bridge to corrective surgery for kyphoscoliosis-associated complete central-airway extrinsic compression in a patient who was considered as too high risk for surgical correction due to her respiratory status. After surgery, the stents were removed and our patient experienced sustained improvement in pulmonary function and the clinical respiratory status.
    No preview · Article · Oct 2014 · Chest
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    ABSTRACT: We evaluated the effect of tracheotomy tubes that enable suction immediately above the cuff on the development of ventilator-associated pneumonia (VAP). Patients without preexisting pneumonia who required tracheotomy were randomly assigned to receive a tracheotomy tube with or without above-the-cuff suction. The suction tube provided 10 mm Hg of continuous wall suction while the tracheotomy tube cuff was inflated. Data regarding the development of VAP, time on the ventilator, and length of stay in the intensive care unit (ICU) were recorded and compared between groups. Eighteen patients were randomized and prospectively evaluated. Nine patients received standard tracheotomy tubes, and 9 received suction-above-the-cuff tracheotomy tubes. The prevalences of VAP were 56% in the control group and 11% in the suction tracheotomy group (p = 0.02). The mean times on the ventilator were 18 +/- 14 days in the control group and 11 +/- 11 days in the suction group (p = 0.12). The mean lengths of ICU stay were 26 +/- 15 days in the control group and 18 +/- 15 days in the suction group (p = 0.14). Use of suction-above-the-cuff tracheotomy tubes significantly decreases the incidence of VAP in ICU patients. There were trends toward decreased time on the ventilator and decreased length of stay in the ICU.
    No preview · Article · Mar 2013 · The Annals of otology, rhinology, and laryngology
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    ABSTRACT: Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is a commonly encountered yet loosely defined clinical entity. ACOS accounts for approximately 15-25% of the obstructive airway diseases and patients experience worse outcomes compared with asthma or COPD alone. Patients with ACOS have the combined risk factors of smoking and atopy, are generally younger than patients with COPD and experience acute exacerbations with higher frequency and greater severity than lone COPD. Pharmacotherapeutic considerations require an integrated approach, first to identify the relevant clinical phenotype(s), then to determine the best available therapy. The authors discuss the array of existing and emerging classes of drugs that could benefit those with ACOS and share their therapeutic approach. A consensus international definition of ACOS is needed to design prospective, randomized clinical trials to evaluate specific drug interventions on important outcomes such as lung function, acute exacerbations, quality of life and mortality.
    Full-text · Article · Mar 2013 · Expert Review of Clinical Pharmacology
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    ABSTRACT: Patients with severe asthma represent only a minority of the total asthma population; however, they account for the majority of the mortality, morbidity, and health care-related cost of this chronic illness. Bronchial thermoplasty is a novel treatment modality that employs radiofrequency energy to alter the smooth muscles of the airways. This therapy represents a radical change in our treatment paradigm from daily repetitive dosing of medications to a truly long-term and potentially permanent attenuation of perhaps the most feared component of asthma--smooth muscle-induced bronchospasm. A large, multicentered, double-blinded, randomized controlled trial employed the unprecedented (but now industry standard for bronchoscopic studies) approach of using sham bronchoscopy as a control. It demonstrated that bronchial thermoplasty is safe, improved quality of life, and decreased frequency of severe exacerbations in the treatment group compared to the control group. Although the mechanism of action of bronchial thermoplasty is not currently completely understood, it should be considered as a valid and potentially valuable option for patients who have severe persistent asthma and who remain symptomatic despite inhaled corticosteroids and long-acting beta-2 agonists. Such patients should however be carefully evaluated at centers with expertise in managing severe asthma patients and with physicians who have experience with this promising new treatment modality.
    Full-text · Article · Nov 2011 · Clinical Reviews in Allergy & Immunology
  • Yasmeen Shaw · Ken Y Yoneda · Andrew L Chan
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    ABSTRACT: Argon plasma coagulation (APC) is a common and safe bronchoscopic technique used in the management of obstructing lesions and hemorrhage in the central airways. Complications of bronchoscopic APC are uncommon and include hemorrhage, perforation and fire in the airways. While bronchoscopic APC has been reported to cause systemic gas embolization and associated cardiovascular collapse, we report a case of cerebral gas embolization that occurred during bronchoscopic APC and highlight underappreciated potential risk factors for its occurrence.
    No preview · Article · Aug 2011 · Respiration
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    ABSTRACT: Asthma in the adult patient is a complex clinical syndrome. Multiple patient phenotypes and subphenotypes exist that contribute to disease heterogeneity. Whether adult asthma begins in utero, develops in childhood, or manifests for the first time in adulthood is not completely understood, nor are the mechanisms fully delineated. In this chapter, we update definitions that apply to this group, emphasize epidemiologic factors and pathogenic mechanisms, diagnosis, therapeutic options, and controversies regarding drug safety. Finally, we provide a brief discussion of biomarker technologies and novel therapies with the potential to impact adult-onset asthma outcomes.
    No preview · Article · Mar 2011 · Clinical Reviews in Allergy & Immunology
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    ABSTRACT: Racial disparities have been reported in non-small cell lung cancer (NSCLC) staging and therapeutic outcomes. We investigated whether such disparities exist in the era of modern noninvasive staging modalities, including positron emission tomography scan use. NSCLC patients from the California Cancer Registry diagnosed between January 1, 1994, and December 31, 2004, were included. The likelihood of obtaining invasive (thoracoscopy, bronchoscopy, and mediastinoscopy) and noninvasive staging procedures (computed tomography, magnetic resonance imaging, and positron emission tomography scans), along with surgical resection, were analyzed using logistic regression adjusted for known confounders. Of 13,762 NSCLC patients, 12,395 with adequate staging information were included. 10,217 patients (82%) were classified as white, 2178 patients (18%) were non-white, and 738 were black patients (6%). No association was seen between race and the use of either noninvasive (odds ratio [OR] = 1.02; p = 0.76) or invasive staging procedures (OR = 0.96; p = 0.44). However, compared with white patients, black patients had a lower likelihood of undergoing surgery, regardless of noninvasive (OR = 0.6; p <0.001) or invasive staging use (OR = 0.63; p = 0.02). There was no survival difference for those who underwent surgery between white and non-white patients, regardless of noninvasive (hazard ratio = 0.95; p = 0.45) or invasive staging (hazard ratio = 1.03; p = 0.79). In contrast to prior published work, we found no difference in rates of both invasive and noninvasive staging between white and non-white patients. However, non-white patients-particularly blacks-were less likely to receive surgery. The reason for the apparent difference in surgical rates could not be explained by the variables we evaluated. Thus, other factors such as personal preference or access to care require further investigation.
    Preview · Article · Sep 2010 · Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer
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    ABSTRACT: In this research, the authors sought to provide experimental data on indoor air quality, and the resulting respiratory impact, for a high-elevation (4550 m), rural community in Ladakh, India. This community is of interest because the primarily nomadic residents burn biomass inside the home for heating and cooking. The concentrations of particulate matter (PM), endotoxin, and carbon monoxide were determined for 6 homes. Lung function data and induced sputum samples were collected for 9 female test-home subjects. In addition, lung function data were collected for 84 additional Ladakhi highlanders at this location. Sputum from 3 visiting scientists (sojourners) was collected and analyzed as well. The average PM concentration ranged from 2 mg/m3 to 7 mg/m3, with 85% of the sampled PM sized as respirable. The average endotoxin concentration ranged from 2.4 ng/m3 to 19 ng/m3, and average carbon monoxide levels ranged from 50 ppm to 120 ppm. Lung function values for the highlander population and the test-home subjects were equal to or greater than predicted, despite the highlanders' significant exposure to indoor pollutants. An induced sputum analysis revealed a significantly greater total inflammatory cell count (M +/- SD, 10(5) cell/mg) in the Ladakhi natives than in the sojourners (107.5 +/- 75.2 vs 7.1 +/- 8.1, p < .01). Although the high levels of indoor pollutants did not correlate with significant decrements in lung function, the induced sputum analysis revealed marked airway inflammation dominated by macrophages and neutrophils. It appears that augmented lung mechanics of this high-altitude population are adaptive to reduce the work of breathing; thus, decrements in lung function go undetected because the true predicted values are greater than expected.
    No preview · Article · Aug 2010 · Archives of Environmental and Occupational Health
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    ABSTRACT: Complications of blind feeding tube (FT) placement include pneumothorax, pneumonia, empyema, and death. A safe and effective method of FT placement is desired. The Davis FT is a novel device that detachably couples to an ultrathin transnasal gastroscope. The objective of this study was to evaluate the safety and efficacy of Davis FT placement. Fifty consecutive patients requiring transpyloric enteral tube feeding underwent placement of the Davis FT. Placement efficacy was evaluated with postplacement radiographs. Patient demographics, route of tube placement, use of sedation, and complications were abstracted. The Davis FT was placed successfully in 50 patients. The mean age of the cohort was 52 (+/- 18) years. Sixty-two percent (31/50) were men. The success rate of nonpulmonary placement was 100% (50/50), and the postpyloric success rate was 96% (48/50). IV sedation was used in 72% (36/50) of placements. Eighty-six percent (43/50) of tubes were placed transnasally. The majority (62%) of esophagogastroduodenoscopies and Davis FT placements was performed by a pulmonologist. Forty-four percent (22/50) of patients had an endotracheal tube, 20% (10/50) had a tracheotomy, and 36% (18/50) had no breathing tube at the time of Davis FT placement. There were no complications. Transpyloric placement of the Davis FT is safe (100%) and effective (96%). The tube can be placed transorally or transnasally with or without sedation. The data suggest that postplacement radiographs are not necessary to confirm placement. Pulmonologists were successful in performing EGD and Davis FT placement.
    No preview · Article · May 2010 · Chest
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    ABSTRACT: Patients with end-stage malignancies often have refractory ascites or pleural effusions requiring repeated paracenteses or thoracenteses. Subcutaneous peritoneal and pleural port catheters are an alternative therapeutic option. We evaluate the clinical utility of this approach and the impact on quality of life (QOL) and home/hospice care. Thirty ports were placed, 16 peritoneal and 14 pleural, in patients with a mean age of 62 years. Retrospective chart review and interviews were held with patients and nursing care providers. Mean follow-up was 59 days. On a 10-point scale, QOL improvement, compared to that prior to port placement, was rated a mean of 9.5 by patients and 9.0 by the nursing staff. Both patients and nurses reported a high degree of convenience (rated at 9.7 and 9.6, respectively) and improvement of symptoms and comfort (9.6 and 9.3, respectively). Nursing staff reported a high degree of comfort (9.9) using the aspiration ports. Six of 14 pleural ports were removed following pleurodesis. One pleural port was removed due to patient discomfort and another due to pneumothorax. Two patients with pleural ports developed tumor seeding in the subcutaneous tissues. Of 14 peritoneal ports, 3 required removal for leaking and probable chemical cellulitis. Four became temporarily occluded with patency restored using tissue plasminogen activator (TPA) infusion. Peritoneal and pleural ports offer a convenient and relatively safe alternative to frequent paracenteses/thoracenteses in the management of refractory ascites and pleural effusions. This approach can improve the QOL for patients with end-stage disease.
    No preview · Article · Aug 2009 · Journal of palliative medicine

  • No preview · Article · Feb 2008 · Journal of Vascular and Interventional Radiology
  • Ken Y Yoneda · Praveen N Mathur · Stefano Gasparini
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    ABSTRACT: The diagnosis and management of a malignant pleural effusion can be one of the most vexing problems faced by physicians and their patients. Lung cancer is the most common primary tumor of origin with a prognosis that is limited, but variable and correlated with performance status (PS). Therefore, with a poor PS and known advanced lung cancer, establishing whether or not an effusion is malignant might not be necessary. Conversely, identifiable subsets of patients will have a much better survival, and establishing a definitive diagnosis could be of critical importance. In the great majority of cases, a diagnosis can be determined by serial thoracenteses with or without closed pleural biopsy. However, thoracoscopy is increasingly being utilized and can expedite the workup by obviating the need for repeated thoracenteses and/or closed pleural biopsy, while in the same setting providing definitive palliative treatment. Although studies comparing diagnostic and treatment strategies are limited, we will present the available data with the intention of providing the practicing oncologist with a practical strategy for the diagnosis and management of malignant pleural effusions due to lung cancer. The interventional pulmonologist can play an important role from diagnosis to palliation, greatly facilitating the care of patients with malignant pleural effusions.
    No preview · Article · Dec 2007 · Clinical Lung Cancer
  • Ken Y. Yoneda · Wayne Monsky · John McMillan

    No preview · Article · Oct 2007 · Chest
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    ABSTRACT: A rare but serious complication of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy is a lung injury syndrome commonly referred to as a drug-induced interstitial lung disease (ILD). It has a typical clinical presentation of rapidly progressive acute or subacute dyspnea and a histopathology of diffuse alveolar damage (DAD). The incidence, severity, and risk factors for EGFR TKI-induced ILD remain poorly understood. Whether concurrent chemotherapy increases its risk is also unclear. The primary focus of this blinded review was to determine the incidence of ILD leading to death in 1059 TRIBUTE patients randomized to chemotherapy plus erlotinib or placebo. All fatal serious adverse events (SAEs) were reviewed by an independent three-person panel composed of a medical oncologist, radiologist, and pulmonologist not associated with the study and without knowledge of treatment assignment. Fatal respiratory SAEs were identified and assigned to one of four potential attributions: progressive cancer, concurrent illness, drug-induced ILD, or other toxicities not related to ILD. Each panel member first made an independent assignation; then each case was discussed jointly. If needed, consensus was reached by vote. Fatal SAEs were reported in 80 of 1059 patients (7.6%): 53 of 526 patients on erlotinib (10.1%) and 27 of 533 on placebo (5.1%) (p < 0.05). Consensus assignation for 41 fatal respiratory SAEs was as follows: cancer, 18 (44%); concurrent illness, 15 (37%); other toxicities not related to ILD, five (12%); ILD, three (7%). All three ILD cases occurred in the erlotinib arm (3/526; 0.6%). The one biopsy-confirmed case of ILD revealed bronchiolitis obliterans organizing pneumonia, a histopathologic finding that has not previously been reported. All three cases of fatal ILD had a typical clinical presentation of acute or subacute onset of dyspnea with rapid progression to respiratory failure. This independent blinded analysis of the TRIBUTE study identified fatal ILD in 0.6% of cases treated with the combination of erlotinib plus chemotherapy, possibly higher than previous reports of EGFR TKIs alone in the non-Japanese population. Fatal ILD alone does not fully account for the imbalance in fatal SAEs observed in TRIBUTE. EGFR TKI-induced fatal ILD typically presents with acute or subacute dyspnea with rapid progression and a typical histopathology of diffuse alveolar damage both consistent with the acute respiratory distress syndrome, but can also be associated with a histopathology of bronchiolitis obliterans organizing pneumonia. Further studies designed to better understand the underlying pathophysiology and risk factors for ILD are needed.
    No preview · Article · Jun 2007 · Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer
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    ABSTRACT: Interstitial lung disease is a rare but serious complication of epidermal growth factor receptor tyrosine kinase inhibitor therapy. Although our understanding of this phenomenon remains incomplete, recently there have been significant insights made into the mechanisms of injury, incidence, risk factors, and its clinical manifestations. Japanese patients appear to be at a higher risk (1.6%-3.5%) than patients in the rest of the world (0.3%), and other risk factors, such as coincident interstitial lung disease, concurrent chemotherapy, previous radiation, preexisting pulmonary fibrosis, and male sex, have been identified. In the majority of cases, the histopathology, the acute and often dramatic clinical presentation, and the radiographic findings resemble acute respiratory distress syndrome. Aside from immediate cessation of the offending agent, the treatment is largely supportive, although corticosteroids appear to be of benefit. The mortality remains high at approximately 30%-50%. We present a review of the incidence, risk factors, clinical manifestations, diagnosis, management, and outcome of this disorder.
    No preview · Article · Jan 2007 · Clinical Lung Cancer

  • No preview · Article · Sep 2006 · Clinical Lung Cancer
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    ABSTRACT: Strenuous exercise may be a significant contributing factor for development of high-altitude pulmonary edema, particularly at low or moderate altitudes. Thus we investigated the effects of heavy cycle ergometer exercise (90% maximal effort) under hypoxic conditions in which the combined effects of a marked increase in pulmonary blood flow and nonuniform hypoxic pulmonary vasoconstriction could add significantly to augment the mechanical stress on the pulmonary microcirculation. We postulated that intense exercise at altitude would result in an augmented permeability edema. We recruited eight endurance athletes and examined their bronchoalveolar lavage fluid (BALF) for red blood cells (RBCs), protein, inflammatory cells, and soluble mediators at 2 and 26 h after intense exercise under normoxic and hypoxic conditions. After heavy exercise, under all conditions, the athletes developed a permeability edema with high BALF RBC and protein concentrations in the absence of inflammation. We found that exercise at altitude (3,810 m) caused significantly greater leakage of RBCs [9.2 (SD 3.1)x10(4) cells/ml] into the alveolar space than that seen with normoxic exercise [5.4 (SD 1.2)x10(4) cells/ml]. At altitude, the 26-h postexercise BALF revealed significantly higher RBC and protein concentrations, suggesting an ongoing capillary leak. Interestingly, the BALF profiles following exercise at altitude are similar to that of early high-altitude pulmonary edema. These findings suggest that pulmonary capillary disruption occurs with intense exercise in healthy humans and that hypoxia augments the mechanical stresses on the pulmonary microcirculation.
    Full-text · Article · Apr 2006 · Journal of Applied Physiology
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    ABSTRACT: • Asthma in adults is composed of a complex group of reversible airway disorders in contrast to childhood asthma that is largely allergic in nature. • Adult-onset asthma may be recently acquired in adulthood or represent various stages of long-standing disease. Atopic adults may carry the genotype of childhood asthma symptomatically into adulthood only to have the phenotype finally expressed because of a powerful trigger, e.g., specific aeroallergen(s) or infection. • Approximately 31 million Americans suffer from asthma. The majority of patients (71%) are adults, whereas fewer than 29% (8.9 million) are children less than 18 yr of age. More women than men are affected with severe adult-onset asthma. Estrogen replacement therapy, respiratory infection with Chlamydia or Mycoplasma, certain occupations, tobacco smoking, gastroesophageal reflux, obesity, and sleep disorders are important risk factors and comorbid conditions. • Asthma and active cigarette smoking interact to cause more severe symptoms, accelerated decline in lung function, and impaired short-term therapeutic response to corticosteroids (CSs). • Simple spirometry, e.g., forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC), detect expiratory flow limitations and lung volumes. Demonstration of reversible obstructive airways disease with spirometry after using albuterol or ipratropium in an adult older than 18 yr old does not alone diagnose adult-onset asthma. Methacholine challenge testing to exclude abnormal airway hyperresponsiveness is safe in adult-onset asthma patients with FEV1 greater than 70% predicted. • High doses of inhaled CSs should be avoided in adult-onset asthma, particularly in the elderly or those with late-onset asthma. The addition of long-acting β2-agonists or antileukotriene drugs is preferable to using high doses of inhaled CSs. All patients using β2-agonists should be monitored for adverse effects, including paradoxical bronchoconstriction. • Given their demonstrated benefit in conditions such as heart failure, coronary artery disease, and hypertension, cardioselective β1-blockers should not be withheld from adults with mild-moderate reversible airway disease. • Patient adherence with prescribed asthma therapy is poor, and it is clearly the overwhelming explanation for poor control of asthma in adults, leading to exacerbations and hospitalizations. Compared with younger hospitalized adults, older hospitalized adults had clear deficiencies, including lower use of peak flow meters and worse asthma self-management knowledge. • Factors independently associated with hospitalization included being female, nonwhite, less educated, and less physically healthy and more frequent asthma symptoms. Chronological age was not an independent risk for hospitalization. Appropriate care for older adults with asthma should address asthma symptoms as in children and younger adults.
    No preview · Chapter · Dec 2005

Publication Stats

240 Citations
116.07 Total Impact Points


  • 2007-2015
    • California State University, Sacramento
      Sacramento, California, United States
  • 2003-2013
    • University of California, Davis
      • Department of Internal Medicine
      Davis, California, United States
  • 2011
    • Davis School District
      Davis, California, United States
  • 2010
    • University of Northern California
      Maryland, United States