Clinical Focus


  • Vascular Surgery
  • Endovascular Surgery
  • Digital Health
  • Health Information Technology
  • Precision Medicine

Academic Appointments


Administrative Appointments


  • Director, Biodesign for Digital Health, Stanford Byers Center for Biodesign (2018 - Present)
  • Medical Director, Wound Clinic, VAPAHCS (2014 - Present)
  • Medical Director, Vascular Laboratory, VAPAHCS (2012 - Present)

Professional Education


  • Medical Education: Boston University School of Medicine (1998) MA
  • Residency: UCSF East Bay Surgery Residency (2005) CA
  • Internship: UCSF East Bay Surgery Residency (1999) CA
  • Board Certification: American Board of Surgery, Vascular Surgery (2010)
  • Board Certification: American Board of Surgery, General Surgery (2007)
  • Fellowship: Northwestern University Medical Center (2007) IL

Research Interests


  • Data Sciences
  • Research Methods
  • Standards
  • Technology and Education

Current Research and Scholarly Interests


We launched a national precision medicine PAD trial called, VascTrac (http://vasctrac.stanford.edu/). This trial is mobile phone based and leverages Apple's ResearchKit Platform to monitor a patient's activity both pre- and post-intervention. We are validating mobile phone surveillance for PAD patients and are currently enrolling.

Clinical Trials


  • Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial Not Recruiting

    Carotid revascularization for primary prevention of stroke (CREST-2) is two independent multicenter, randomized controlled trials of carotid revascularization and intensive medical management versus medical management alone in patients with asymptomatic high-grade carotid stenosis. One trial will randomize patients in a 1:1 ratio to endarterectomy versus no endarterectomy and another will randomize patients in a 1:1 ratio to carotid stenting with embolic protection versus no stenting. Medical management will be uniform for all randomized treatment groups and will be centrally directed.

    Stanford is currently not accepting patients for this trial. For more information, please contact Brittanie D Baughman, 650-493-5000 Ext. 68632.

    View full details

  • Distributed Registry Not Recruiting

    The purpose of this study is to test if a patient can be directly connected to a quality assurance (QA) database, traditionally known as a registry. Patient-reported outcomes (PRO) data will be entered into the database directly from a patient's mobile phone from their index procedure for 12 months. The investigators hope this study to be a "proof of concept" for such a distributed registry and evaluate 1) consistency of data acquisition, 2) engagement of patients, 3) overall value of patient-reported outcomes to enhance long term follow up.

    Stanford is currently not accepting patients for this trial. For more information, please contact Doran S Triggs, BS, 650-852-3459.

    View full details

  • Study of the Effectiveness of Telmisartan in Slowing the Progression of Abdominal Aortic Aneurysms Not Recruiting

    The purpose of this study is to determine if telmisartan is effective in slowing the progression of abdominal aortic aneurysms and reducing circulating concentrations of Abdominal Aortic Aneurysms (AAA) biomarkers.

    Stanford is currently not accepting patients for this trial. For more information, please contact Ronald Dalman, (650) 723 - 2169.

    View full details

  • VascTrac Peripheral Arterial Disease (PAD) Study Not Recruiting

    VascTrac is a mobile medical application that tracks users' physical activity levels in order to predict endovascular failure of patients with Peripheral Artery Disease.

    Stanford is currently not accepting patients for this trial.

    View full details

2024-25 Courses


All Publications


  • Utility of smart watches for identifying arrhythmias in children. Communications medicine Zahedivash, A., Chubb, H., Giacone, H., Boramanand, N. K., Dubin, A. M., Trela, A., Lencioni, E., Motonaga, K. S., Goodyer, W., Navarre, B., Ravi, V., Schmiedmayer, P., Bikia, V., Aalami, O., Ling, X. B., Perez, M., Ceresnak, S. R. 2023; 3 (1): 167

    Abstract

    Arrhythmia symptoms are frequent complaints in children and often require a pediatric cardiology evaluation. Data regarding the clinical utility of wearable technologies are limited in children. We hypothesize that an Apple Watch can capture arrhythmias in children.We present an analysis of patients ≤18 years-of-age who had signs of an arrhythmia documented by an Apple Watch. We include patients evaluated at our center over a 4-year-period and highlight those receiving a formal arrhythmia diagnosis. We evaluate the role of the Apple Watch in arrhythmia diagnosis, the results of other ambulatory cardiac monitoring studies, and findings of any EP studies.We identify 145 electronic-medical-record identifications of Apple Watch, and find arrhythmias confirmed in 41 patients (28%) [mean age 13.8 ± 3.2 years]. The arrythmias include: 36 SVT (88%), 3 VT (7%), 1 heart block (2.5%) and wide 1 complex tachycardia (2.5%). We show that invasive EP study confirmed diagnosis in 34 of the 36 patients (94%) with SVT (2 non-inducible). We find that the Apple Watch helped prompt a workup resulting in a new arrhythmia diagnosis for 29 patients (71%). We note traditional ambulatory cardiac monitors were worn by 35 patients (85%), which did not detect arrhythmias in 10 patients (29%). In 73 patients who used an Apple Watch for recreational or self-directed heart rate monitoring, 18 (25%) sought care due to device findings without any arrhythmias identified.We demonstrate that the Apple Watch can record arrhythmia events in children, including events not identified on traditionally used ambulatory monitors.

    View details for DOI 10.1038/s43856-023-00392-9

    View details for PubMedID 38092993

    View details for PubMedCentralID 4937287

  • CardinalKit: open-source standards-based, interoperable mobile development platform to help translate the promise of digital health. JAMIA open Aalami, O., Hittle, M., Ravi, V., Griffin, A., Schmiedmayer, P., Shenoy, V., Gutierrez, S., Venook, R. 2023; 6 (3): ooad044

    Abstract

    Smartphone devices capable of monitoring users' health, physiology, activity, and environment revolutionize care delivery, medical research, and remote patient monitoring. Such devices, laden with clinical-grade sensors and cloud connectivity, allow clinicians, researchers, and patients to monitor health longitudinally, passively, and persistently, shifting the paradigm of care and research from low-resolution, intermittent, and discrete to one of persistent, continuous, and high resolution. The collection, transmission, and storage of sensitive health data using mobile devices presents unique challenges that serve as significant barriers to entry for care providers and researchers alike. Compliance with standards like HIPAA and GDPR requires unique skills and practices. These requirements make off-the-shelf technologies insufficient for use in the digital health space. As a result, budget, timeline, talent, and resource constraints are the largest barriers to new digital technologies. The CardinalKit platform is an open-source project addressing these challenges by focusing on reducing these barriers and accelerating the innovation, adoption, and use of digital health technologies. CardinalKit provides a mobile template application and web dashboard to enable an interoperable foundation for developing digital health applications. We demonstrate the applicability of CardinalKit to a wide variety of digital health applications across 18 innovative digital health prototypes.

    View details for DOI 10.1093/jamiaopen/ooad044

    View details for PubMedID 37485467

    View details for PubMedCentralID PMC10356573

  • Characterizing patient-reported claudication treatment goals to support patient-centered treatment selection and measurement strategies. Journal of vascular surgery Powell, C. A., Kim, G. Y., Edwards, S. N., Aalami, O., Treat-Jacobson, D., Byrnes, M. E., Osborne, N. H., Corriere, M. A. 2022

    Abstract

    OBJECTIVE: Patient-reported outcomes (PRO) are increasingly emphasized for peripheral artery disease (PAD). Patient-defined treatment goals and expectations, however, are poorly understood and may not be achievable or aligned with guidelines or traditional outcomes. We evaluated patient-reported treatment goals among patients with claudication and associations between patient characteristics, goals, and PAD-specific PRO scores.METHODS: Patients diagnosed with claudication were prospectively recruited. Patient-defined treatment goals and outcomes related to walking distance, duration, and speed were quantified using multiple choice survey items. Free-text items were used to identify activities other than walking distance, duration or speed associated with PAD symptoms and treatment goals. The Peripheral Artery Disease Quality of Life (PADQOL) and Walking Impairment Questionnaire (WIQ) instruments were included as PRO. Treatment goal categories were compared with PRO percentile scores using confidence intervals, categorical tests, and logistic regression models. Associations between patient characteristics and PRO were evaluated using linear and ordinal logistic regression models.RESULTS: 150 patients meeting the inclusion criteria participated; of these, 144 (96%) viewed the entire survey. Mean age was 70.0±11.3 years, and 32.9% were women. The majority of respondents self-reported race as white (N=135), followed by Black (N=3), Asian (N=2), American Indian (N=2) and other/unknown (N=2). Two participants self-reported Hispanic ethnicity. Primary treatment goals were: increased walking distance or duration without stopping (62.0%), ability to perform a specific activity or task (23.0%), increased walking speed (8.0%), or other/none of the above (7.0%). Specific activities associated with symptoms or goals included: outdoor recreation (38.5%), labor-related tasks (30.7%), sports (26.9%), climbing stairs (23.1%), uphill walking (19.2%), and shopping (6%). Among patients choosing increased walking distance and duration as primary goals, 64% indicated a distance ≥0.5 miles (2640 feet) and 59% indicated a duration ≥ 30 minutes as minimum increases consistent with meaningful improvement. Increasing age was associated with lower odds of a distance improvement goal ≥ 0.5 miles (OR 0.68 per 5 years; 95% CL 0.51-0.92; P=0.012) or duration improvement goal ≥ 30 minutes (OR 0.76 per 5-years; 95% CL 0.58-0.99; P=0.047). Patient characteristics associated with PADQOL percentile scores included age, ABI, and gender. ABI was the only patient characteristic associated with WIQ percentile scores.CONCLUSIONS: Patients define treatment goals based on activities and expectations that may influence perceived outcomes. Minimum walking distance and duration increases consistent with meaningful improvement exceed published minimum important difference criteria for many patients and would be uncaptured using common clinic-based walking tests. Patient age is associated with both treatment goals and PRO scores, and related floor and ceiling effects may influence sensitivity to PRO change among older and younger patients. Heterogeneity in treatment goals supports consideration of tailored approaches informed by patient characteristics and perspectives regarding treatment success versus failure.

    View details for DOI 10.1016/j.jvs.2022.09.002

    View details for PubMedID 36087833

  • Use of an App-Based Exercise Therapy Program Including Cognitive Behavioral Techniques for the Management of Intermittent Claudication. Journal of vascular surgery Aalami, O. O., Lin, J., Savage, D., Ho, V., Bertges, D., Corriere, M. 2022

    Abstract

    OBJECTIVES: Clinical practice guidelines recommend supervised exercise therapy (SET) as first-line therapy for patients with peripheral artery disease (PAD) and intermittent claudication (IC). The Society for Vascular Surgery (SVS) Appropriate Use Criteria (AUC) for IC deems exercise therapy as appropriate for all patients with IC. However, compliance with recommendations for the use of exercise therapy is often poor due to the lack of availability, patient travel requirements, and cost. Results of home-based exercise therapy programs have been mixed with a trend towards improved results with more frequent patient engagement. The feasibility, utilization, and effectiveness of a 12-week app-based structured exercise therapy program using cognitive behavioral techniques (CBT) for IC was evaluated.METHODS: Patients with PAD (confirmed by abnormal ABI or TBI) and IC were recruited prospectively to participate in SVS SET, a 12-week app-based exercise therapy program. Participants performed home six-minute walk tests, completed quality of life (QoL) surveys, received education options via micro training courses (What is PAD?, Exercise, Nutrition), and ongoing health coaching utilizing CBT. They were instructed to record at least three 30-minute exercise therapy walks a week using their personal mobile phones. Programming also included "daily doses" of health education, coaching and reminders sent via text message.RESULTS: One hundred and thirty-nine patients (37% women, mean age 65) were enrolled across 20 institutions (44% offered in-person exercise therapy programs). One hundred twenty (86%) of patients completed the program. Participants recorded 201,163 minutes of walking 8,013,520 steps with the exercise therapy program, completing a total of 5,049 SET Walks. Nineteen (14%) of enrolled participants became inactive because they either paused (14 participants: medical reasons, travel, or other) or withdrew (5 participants: security concerns, lack of motivation). Ninety-two percent of patients met their stated CBT SMART (Specific, Measurable, Achievable, Relevant, and Time-Bound) goals. Freedom from intervention at 6 months was 92% and 69% at 12 months.CONCLUSIONS: Deployment of a 12-Week app-based exercise therapy program for PAD incorporating CBT was feasible in achieving 86% program completion and effective at meeting guideline recommended activity goals. Ninety-two percent of participants achieved their CBT SMART goals. Utilization of exercise therapy was increased by virtue of offering this program at institutions which did not offer exercise therapy.

    View details for DOI 10.1016/j.jvs.2022.06.087

    View details for PubMedID 35872328

  • A Comparative Utility Score for Digital Health Tools. Journal of medical systems Burton, J. C., Regala, S., Williams, D., Desai, A., He, H., Aalami, O., Mariano, E. R., Stafford, R. S., Mudumbai, S. C. 2022; 46 (6): 34

    Abstract

    Digital health tools (DHT) are increasingly poised to change healthcare delivery given the Coronavirus Disease 2019 (COVID-19) pandemic and the drive to telehealth. Establishing the potential utility of a given DHT could aid in identifying how it could be best used and further opportunities for healthcare improvement. We propose a metric, a Utility Factor Score, which quantifies the benefits of a DHT by explicitly defining adherence and linking it directly to satisfaction and health goals met. To provide data for how the comparative utility score can or should work, we illustrate in detail the application of our metrics across four DHTs with two simulated users. The Utility Factor Score can potentially facilitate integration of DHTs into various healthcare settings and should be evaluated within a clinical study.

    View details for DOI 10.1007/s10916-022-01821-3

    View details for PubMedID 35511408

  • Vascular1: Evaluation of a Virtual Reality Ultrasound Guided Femoral Artery Access Training Module Shenoy, V., Khan, S. I., Nguyen, E., Caraccio, W., Farooqui, N., Aalami, O. MOSBY-ELSEVIER. 2021: E261
  • Modest Gains After an 8-Week Exercise Program Correlate With Reductions in Non-traditional Markers of Cardiovascular Risk FRONTIERS IN CARDIOVASCULAR MEDICINE Liang, G., Huang, X., Hirsch, J., Mehmi, S., Fonda, H., Chan, K., Huang, N. F., Aalami, O., Froelicher, V. F., Lee, D. P., Myers, J., Lee, A. S., Nguyen, P. K. 2021; 8: 669110

    Abstract

    Background: Although engaging in physical exercise has been shown to reduce the incidence of cardiovascular events, the molecular mechanisms by which exercise mediates these benefits remain unclear. Based on epidemiological evidence, reductions in traditional risk factors only accounts for 50% of the protective effects of exercise, leaving the remaining mechanisms unexplained. The objective of this study was to determine whether engaging in a regular exercise program in a real world clinical setting mediates cardiovascular protection via modulation of non-traditional risk factors, such as those involved in coagulation, inflammation and metabolic regulation. Methods and Results: We performed a prospective, cohort study in 52 sedentary patients with cardiovascular disease or cardiovascular risk factors at two tertiary medical centers between January 1, 2016 and December 31, 2019. Prior to and at the completion of an 8-week exercise program, we collected information on traditional cardiovascular risk factors, exercise capacity, and physical activity and performed plasma analysis to measure levels of fibrinolytic, inflammatory and metabolic biomarkers to assess changes in non-traditional cardiovascular risk factors. The median weight change, improvement in physical fitness, and change in physical activity for the entire cohort were: -4.6 pounds (IQR: +2 pounds, -11.8 pounds), 0.37 METs (IQR: -0.076 METs, 1.06 METs), and 252.7 kcals/week (IQR: -119, 921.2 kcals/week). In addition to improvement in blood pressure and cholesterol, patients who lost at least 5 pounds, expended at least 1,000 additional kcals/week, and/or achieved ≥0.5 MET increase in fitness had a significant reduction in plasminogen activator inhibitor-1 [9.07 ng/mL (95% CI: 2.78-15.35 ng/mL); P = 0.026], platelet derived growth factor beta [376.077 pg/mL (95% CI: 44.69-707.46 pg/mL); P = 0.026); and angiopoietin-1 [(1104.11 pg/mL (95% CI: 2.92-2205.30 pg/mL); P = 0.049)]. Conclusion: Modest improvements in physical fitness, physical activity, and/or weight loss through a short-term exercise program was associated with decreased plasma levels of plasminogen activator inhibitor, platelet derived growth factor beta, and angiopoietin, which have been associated with impaired fibrinolysis and inflammation.

    View details for DOI 10.3389/fcvm.2021.669110

    View details for Web of Science ID 000668338500001

    View details for PubMedID 34222367

    View details for PubMedCentralID PMC8245677

  • Reliability and repeatability of a smartphone-based 6-min walk test as a patient-centred outcome measure. European heart journal. Digital health Mak, J., Rens, N., Savage, D., Nielsen-Bowles, H., Triggs, D., Talgo, J., Gandhi, N., Gutierrez, S., Gutierrez, S., Aalami, O. 2021; 2 (1): 77-87

    Abstract

    The 6-min-walk test (6MWT) is a validated proxy for frailty and a predictor of clinical outcomes, yet is not widely used due to implementation challenges. This comparative effectiveness study assesses the reliability and repeatability of a home-based 6MWT compared to in-clinic 6MWTs in patients with cardiovascular disease.One hundred and ten (110) patients scheduled for cardiac or vascular surgery were enrolled during a study period from June 2018 to December 2019 at the Palo Alto VA Hospital. Subjects were provided with an Apple iPhone 7 and Apple Watch Series 3 loaded with the VascTrac research study application and performed a supervised in-clinic 6MWT during enrolment, at 2 weeks, 1, 3, and 6 months post-operatively. Subjects also received notifications to perform at-home smartphone-based 6MWTs once a week for a duration of 6 months. Test-retest reliability of in-clinic measurements and at-home measurements was assessed with an industry standard Cronbach's alpha reliability test. Test-retest reliability for in-clinic ground truth 6MWT steps vs. in-clinic iPhone 6MWT steps was 0·99, showing high reliability between the two tested measurements. When comparing for in-clinic ground truth 6MWT steps vs. neighbouring at-home iPhone 6MWT steps, reliability was 0·74.Running the test-reliability test on both measurements shows that an iPhone 6MWT test is reliable compared to an in-clinic ground truth measurement in patients with cardiovascular disease.

    View details for DOI 10.1093/ehjdh/ztab018

    View details for PubMedID 36711173

    View details for PubMedCentralID PMC9707915

  • Applications of Mobile Health Technology in Surgical Innovation. JAMA surgery Aalami, O., Ingraham, A., Arya, S. 2021

    View details for DOI 10.1001/jamasurg.2020.6251

    View details for PubMedID 33533899

  • Activity data from wearables as an indicator of functional capacity in patients with cardiovascular disease. PloS one Rens, N. n., Gandhi, N. n., Mak, J. n., Paul, J. n., Bent, D. n., Liu, S. n., Savage, D. n., Nielsen-Bowles, H. n., Triggs, D. n., Ata, G. n., Talgo, J. n., Gutierrez, S. n., Aalami, O. n. 2021; 16 (3): e0247834

    Abstract

    Smartphone and wearable-based activity data provide an opportunity to remotely monitor functional capacity in patients. In this study, we assessed the ability of a home-based 6-minute walk test (6MWT) as well as passively collected activity data to supplement or even replace the in-clinic 6MWTs in patients with cardiovascular disease.We enrolled 110 participants who were scheduled for vascular or cardiac procedures. Each participant was supplied with an iPhone and an Apple Watch running the VascTrac research app and was followed for 6 months. Supervised 6MWTs were performed during clinic visits at scheduled intervals. Weekly at-home 6MWTs were performed via the VascTrac app. The app passively collected activity data such as daily step counts. Logistic regression with forward feature selection was used to assess at-home 6MWT and passive data as predictors for "frailty" as measured by the gold-standard supervised 6MWT. Frailty was defined as walking <300m on an in-clinic 6MWT.Under a supervised in-clinic setting, the smartphone and Apple Watch with the VascTrac app were able to accurately assess 'frailty' with sensitivity of 90% and specificity of 85%. Outside the clinic in an unsupervised setting, the home-based 6MWT is 83% sensitive and 60% specific in assessing "frailty." Passive data collected at home were nearly as accurate at predicting frailty on a clinic-based 6MWT as was a home-based 6MWT, with area under curve (AUC) of 0.643 and 0.704, respectively.In this longitudinal observational study, passive activity data acquired by an iPhone and Apple Watch were an accurate predictor of in-clinic 6MWT performance. This finding suggests that frailty and functional capacity could be monitored and evaluated remotely in patients with cardiovascular disease, enabling safer and higher resolution monitoring of patients.

    View details for DOI 10.1371/journal.pone.0247834

    View details for PubMedID 33760846

  • Telemedicine Platforms and Their Use in the Coronavirus Disease-19 Era to Deliver Comprehensive Vascular Care. Journal of vascular surgery Lin, J. C., Humphries, M. D., Shutze, W. P., Aalami, O. O., Fischer, U. M., Hodgson, K. J. 2020

    Abstract

    Implementation of telemedicine for patient encounters optimizes personal safety and allows for continuity of patient care. Embracing telehealth reduces the use of personal protective equipment (PPE) and other resources consumed during in-person visits. The use of telehealth has increased to historic levels in response to the coronavirus disease 2019 (COVID-19) pandemic. Telehealth may be a key modality to fight against COVID-19, allowing us to take care of patients, conserve PPE, and protect healthcare workers all while minimizing the risk of viral spread. We must not neglect vascular health issues while the coronavirus pandemic continues to flood many hospitals and keep people confined to their homes. Patients are not immune to diseases and illnesses such as stroke, critical limb ischemia, and deep vein thrombosis while being confined to their homes and afraid to visit hospitals. Emerging from the COVID-19 crisis, incorporating telemedicine into routine medical care is transformative. By leveraging digital technology, the authors discuss their experience with the implementation, workflow, coding, and reimbursement issues of telehealth during the COVID-19 era.

    View details for DOI 10.1016/j.jvs.2020.06.051

    View details for PubMedID 32622075

  • National assessment of availability, awareness, and utilization of supervised exercise therapy for peripheral artery disease patients with intermittent claudication. Journal of vascular surgery Dua, A., Gologorsky, R., Savage, D., Rens, N., Gandhi, N., Brooke, B., Corriere, M., Jackson, E., Aalami, O. 2019

    Abstract

    BACKGROUND: Supervised exercise therapy (SET) is an inexpensive, low-risk, and effective option when compared with invasive therapies for the treatment of patients with peripheral artery disease (PAD) and intermittent claudication. Randomized, controlled trials have demonstrated the benefits of SET in improving maximum walking distance in intermittent claudication patients, and society guidelines recommend SET as first-line therapy. In 2017, the Centers for Medicare & Medicaid Services (CMS) added coverage of SET. We aimed to evaluate the availability and use of SET programs, determine the awareness of SET CMS coverage in the United States, and gauge the academic interest in SET in the vascular community.METHODS: An eight-question online survey regarding SET coverage, reimbursement, barriers to prescription, and SET use was sent to 900 vascular surgeons, cardiologists, and vascular medicine physicians across the United States. The most recent 2-year programs for the Vascular Annual Meeting, Midwestern Vascular Society, Eastern Vascular Society, and Western Vascular Society were reviewed to identify SET-related abstracts and gauge academic interest and awareness for SET within the vascular surgery community.RESULTS: We received 135 physician responses (15%) to the survey. All 50 states were represented. The majority of responders (54%) stated that there was no SET program at their facility, and 5% did not know if there was a SET program available. Of those who did have a SET program available, 81% were associated with cardiac rehabilitation and 19% had a PAD-specific program. A significant number of physicians (49%) had never referred a patient for SET. Twenty-six percent were not aware that CMS covered SET sessions. Of the physicians who were aware of CMS reimbursement, 36% had never referred a patient to a SET program. Of all surveyed, 98% indicated they would refer patients to a SET program if one was available. Top barriers to use of a SET program included (1) no SET center availability and (2) significant cost or travel expense to the patient. A review of major vascular surgery meeting programs for the last 2years yielded no identification of a SET-related abstract.CONCLUSIONS: There is a lack of both availability and use of SET for patients with PAD with claudication, despite guideline recommendations and CMS reimbursement for SET sessions in the United States. When SET is offered, it is typically through cardiac rehabilitation programs which is not focused on PAD. Travel distance, lack of SET program availability, and low reimbursement rates are primary areas that could be addressed to improve use.

    View details for DOI 10.1016/j.jvs.2019.08.238

    View details for PubMedID 31699514

  • Mobile Engagement for Walking in Patients With Claudication Aalami, O., Savage, D., Rens, N., Meng, E., Triggs, D. MOSBY-ELSEVIER. 2019: E230
  • National Assessment of Availability, Awareness, and Utilization of Supervised Exercise Therapy for Peripheral Artery Disease in Patients With Intermittent Claudication Dua, A., Savage, D., Rens, N., Gandhi, N., Brooke, B. S., Corriere, M., Jackson, E., Aalami, O. MOSBY-ELSEVIER. 2019: E55–E56
  • Clinical validation of smartphone-based activity tracking in peripheral artery disease patients. NPJ digital medicine Ata, R., Gandhi, N., Rasmussen, H., El-Gabalawy, O., Gutierrez, S., Ahmad, A., Suresh, S., Ravi, R., Rothenberg, K., Aalami, O. 2018; 1: 66

    Abstract

    Peripheral artery disease (PAD) is a vascular disease that leads to reduced blood flow to the limbs, often causing claudication symptoms that impair patients' ability to walk. The distance walked during a 6-min walk test (6MWT) correlates well with patient claudication symptoms, so we developed the VascTrac iPhone app as a platform for monitoring PAD using a digital 6MWT. In this study, we evaluate the accuracy of the built-in iPhone distance and step-counting algorithms during 6MWTs. One hundred and fourteen (114) participants with PAD performed a supervised 6MWT using the VascTrac app while simultaneously wearing an ActiGraph GT9X Activity Monitor. Steps and distance-walked during the 6MWT were manually measured and used to assess the bias in the iPhone CMPedometer algorithms. The iPhone CMPedometer step algorithm underestimated steps with a bias of -7.2% ± 13.8% (mean ± SD) and had a mean percent difference with the Actigraph (Actigraph-iPhone) of 5.7% ± 20.5%. The iPhone CMPedometer distance algorithm overestimated distance with a bias of 43% ± 42% due to overestimation in stride length. Our correction factor improved distance estimation to 8% ± 32%. The Ankle-Brachial Index (ABI) correlated poorly with steps (R = 0.365) and distance (R = 0.413). Thus, in PAD patients, the iPhone's built-in distance algorithm is unable to accurately measure distance, suggesting that custom algorithms are necessary for using iPhones as a platform for monitoring distance walked in PAD patients. Although the iPhone accurately measured steps, more research is necessary to establish step counting as a clinically meaningful metric for PAD.

    View details for DOI 10.1038/s41746-018-0073-x

    View details for PubMedID 31304343

    View details for PubMedCentralID PMC6550212

  • Clinical validation of smartphone-based activity tracking in peripheral artery disease patients NPJ DIGITAL MEDICINE Ata, R., Gandhi, N., Rasmussen, H., El-Gabalawy, O., Gutierrez, S., Ahmad, A., Suresh, S., Ravi, R., Rothenberg, K., Aalami, O. 2018; 1
  • Septic Pulmonary Emboli From Peripheral Suppurative Thrombophlebitis: A Case Report and Literature Review. Vascular and endovascular surgery Ho, V. T., Rothenberg, K. A., McFarland, G., Tran, K., Aalami, O. O. 2018: 1538574418779469

    Abstract

    BACKGROUND: We report the case of a 90-year old woman who presented with septic pulmonary emboli due to suppurative thrombophlebitis at an old peripheral intravenous site.METHODS: After unsuccessful treatment with antibiotics, the patient was taken to the operating room for excision and drainage of the purulent superficial vein.RESULTS: We review the literature and discuss the presentation, risk factors, treatment options, and complications of this often-overlooked disease entity.CONCLUSIONS: Suppurative thrombophlebitis is a rare but morbid disease that requires a high level of clinical suspicion to diagnose.

    View details for DOI 10.1177/1538574418779469

    View details for PubMedID 29909751

  • Utilizing Smartphone-Based Machine Learning in Medical Monitor Data Collection: Seven Segment Digit Recognition. AMIA ... Annual Symposium proceedings. AMIA Symposium Shenoy, V. N., Aalami, O. O. 2017; 2017: 1564-1570

    Abstract

    Biometric measurements captured from medical devices, such as blood pressure gauges, glucose monitors, and weighing scales, are essential to tracking a patient's health. Trends in these measurements can accurately track diabetes, cardiovascular issues, and assist medication management for patients. Currently, patients record their results and date of measurement in a physical notebook. It may be weeks before a doctor sees a patient's records and can assess the health of the patient. With a predicted 6.8 billion smartphones in the world by 20221, health monitoring platforms, such as Apple's HealthKit2, can be leveraged to provide the right care at the right time. This research presents a mobile application that enables users to capture medical monitor data and send it to their doctor swiftly. A key contribution of this paper is a robust engine that can recognize digits from medical monitors with an accuracy of 98.2%.

    View details for PubMedID 29854226

    View details for PubMedCentralID PMC5977613

  • A Cross-Sectional Study of Prominent US Mobile Health Applications: Evaluating the Current Landscape. AMIA ... Annual Symposium proceedings. AMIA Symposium Fougerouse, P., Yasini, M., Marchand, G., Aalami, O. O. 2017; 2017: 715–23

    Abstract

    Mobile health (mHealth) could offer unprecedented opportunity to provide medical support closer to the users. We have selected some relevant criteria to describe 100 apps from Google Play store and Apple's App Store's top suggestions in medical category. These characteristics were compared based on the paid or free nature of the apps, the target users: consumers or healthcare professionals, and the platform: Android or iOS. Seventeen provided functionalities and 27 medical subjects covered by these apps were also extracted. Our study shows that even in top rated mHealth apps, a high proportion lacks some basic criteria regarding the quality of the apps including the presence of a privacy policy, describing content sources, participation of the target users in the app development, etc. Paid apps did not ensure better quality compared to free apps. The current mHealth market is not mature enough to be used widely and recommended by healthcare professionals.

    View details for PubMedID 29854137

  • Use of a proactive duplex ultrasound protocol for hemodialysis access. Journal of vascular surgery Itoga, N. K., Ullery, B. W., Tran, K., Lee, G. K., Aalami, O. O., Bech, F. R., Zhou, W. 2016; 64 (4): 1042-1049 e1

    Abstract

    Arteriovenous fistula (AVF) creation is the preferred approach for hemodialysis access; however, the maturation of AVFs is known to be poor. We established a proactive early duplex ultrasound (DUS) surveillance protocol for evaluating AVFs before attempted access. This study determined the effect of this protocol related to improving AVF maturation.From 2008 to 2013, 153 patients received new upper extremity AVFs and an early DUS surveillance protocol at a single academic institution. The protocol involved an early DUS evaluation before hemodialysis cannulation of the AVF at 4 to 8 weeks after AVF creation. A positive DUS result was identified as a peak systolic velocity of >375 cm/s or a >50% stenosis on gray scale imaging, along with decreased velocity in the outflow vein. Patients with positive DUS findings underwent prophylactic endovascular or open intervention to assist with AVF maturation. Nature of secondary interventions, as well as AVF patency and maturation, were assessed. Overall clinical outcomes and fistula patency were investigated.During the study period, 183 upper extremity AVFs were created in 153 patients, including 82 radiocephalic, 63 brachiocephalic, and 38 brachiobasilic AVFs. A mortality rate of 43% (n = 66) was observed in a median follow-up period of 34.5 months (interquartile range, 19.6-46.9). A total of 164 early DUS were performed at a median of 6 weeks (interquartile range, 3.4-9.6 weeks) after the initial creation. Early DUS showed nine AVFs were occluded and were excluded from further analysis. Hemodynamically significant lesions were found in 62 AVFs (40%); however, only 17 (11%) were associated with an abnormal physical examination. Positive DUS finding prompted a secondary intervention in 81% of the patients. Among those with positive early DUS findings, AVF maturation was 70% in those undergoing a secondary intervention compared with 25% in those not undergoing a prophylactic intervention (P = .011). Primary-assisted patency for AVFs with early positive and negative DUS findings were 83% and 96% at 6 months, 64% and 89% at 1 year, and 52% and 82% at 2 years, respectively (P < .001).Early DUS surveillance of AVFs before initial access is reasonable to identify problematic AVFs that may not be reliably detected on clinical examination. Although DUS criteria for AVFs have yet to be universally accepted, proactive early postoperative DUS interrogation assists in the early detection of dysfunctional AVFs and improvement of fistula maturation. Despite improved patency in those with positive DUS findings who undergo prophylactic secondary intervention, overall patency remains inferior to those without an abnormality detected on early DUS imaging.

    View details for DOI 10.1016/j.jvs.2016.03.442

    View details for PubMedID 27183858

  • Novel Use of Google Glass for Procedural Wireless Vital Sign Monitoring. Surgical innovation Liebert, C. A., Zayed, M. A., Aalami, O., Tran, J., Lau, J. N. 2016; 23 (4): 366-373

    Abstract

    This study investigates the feasibility and potential utility of head-mounted displays for real-time wireless vital sign monitoring during surgical procedures.In this randomized controlled pilot study, surgery residents (n = 14) performed simulated bedside procedures with traditional vital sign monitors and were randomized to addition of vital sign streaming to Google Glass. Time to recognition of preprogrammed vital sign deterioration and frequency of traditional monitor use was recorded. User feedback was collected by electronic survey.The experimental group spent 90% less time looking away from the procedural field to view traditional monitors during bronchoscopy (P = .003), and recognized critical desaturation 8.8 seconds earlier; the experimental group spent 71% (P = .01) less time looking away from the procedural field during thoracostomy, and recognized hypotension 10.5 seconds earlier. Trends toward earlier recognition of deterioration did not reach statistical significance. The majority of participants agreed that Google Glass increases situational awareness (64%), is helpful in monitoring vitals (86%), is easy to use (93%), and has potential to improve patient safety (85%).In this early feasibility study, use of streaming to Google Glass significantly decreased time looking away from procedural fields and resulted in a nonsignificant trend toward earlier recognition of vital sign deterioration. Vital sign streaming with Google Glass or similar platforms is feasible and may enhance procedural situational awareness.

    View details for DOI 10.1177/1553350616630142

    View details for PubMedID 26848138

  • Erratum to: 'TElmisartan in the management of abDominal aortic aneurYsm (TEDY): The study protocol for a randomized controlled trial'. Trials Morris, D. R., Cunningham, M. A., Ahimastos, A. A., Kingwell, B. A., Pappas, E., Bourke, M., Reid, C. M., Stijnen, T., Dalman, R. L., Aalami, O. O., Lindeman, J. H., Norman, P. E., Walker, P. J., Fitridge, R., Bourke, B., Dear, A. E., Pinchbeck, J., Jaeggi, R., Golledge, J. 2016; 17 (1): 43-?

    View details for DOI 10.1186/s13063-016-1183-x

    View details for PubMedID 26791257

    View details for PubMedCentralID PMC4721016

  • A Prospective Evaluation of Using IVUS during Percutaneous Superficial Femoral Artery Interventions ANNALS OF VASCULAR SURGERY Hitchner, E., Zayed, M., Varu, V., Lee, G., Aalami, O., Zhou, W. 2015; 29 (1): 28-33

    Abstract

    The outcomes of endovascular interventions of the superficial femoral artery (SFA) are variable. Completion angiography is typically performed to confirm satisfactory outcomes after SFA angioplasty and/or stenting. However, two-dimensional angiography may not accurately reflect the extent of residual stenosis. We sought to determine whether intravascular ultrasound (IVUS) can help with residual disease assessment and procedure outcome.Patients with anticipated SFA disease were prospectively recruited to the study. Patients with primary SFA disease on diagnostic angiography were included. After SFA endovascular intervention with angioplasty and/or stenting, a completion angiogram was performed to confirm satisfactory results before IVUS evaluation. IVUS-detected maximal residual stenosis, maximal residual lesion volume, and number of nonconsecutive posttreatment SFA segments with >50% residual stenosis were evaluated. Periprocedural ankle-brachial indexes (ABIs), Short Form 36 (SF-36) surveys, and Walking Impairment Questionnaires were also collected.Fifty-nine patients were prospectively enrolled. Thirty-three received angioplasty only, and 26 received angioplasty and stenting. All patients were men, mean age was 67 years, and major comorbidities included coronary artery disease (53%), active smoking (56%), hypertension (88%), and diabetes (68%). The angioplasty-only cohort had more nonconsecutive areas of >50% residual stenosis (P = 0.004), greater residual stenosis (P = 0.03), and smaller minimal lumen diameters after treatment (P = 0.01) than the angioplasty and stenting cohort. However, there was no significant difference in ABI between the 2 groups and no difference in ABI improvement after intervention. Sixty-four percent of all patients demonstrated a >0.2 increase in postintervention ABI. Improvement in ABI at 1 month after procedure significantly correlated with postintervention SF-36 survey physical scores (r = 0.435, P = 0.007).IVUS evaluation provides more-accurate intraprocedural insight on the extent of residual stenosis after SFA interventions. Future studies are warranted to determine whether IVUS-guided postangioplasty and/or stenting can impact long-term interventional outcome.

    View details for DOI 10.1016/j.avsg.2014.07.026

    View details for Web of Science ID 000346239900005

    View details for PubMedID 25194552

  • TElmisartan in the management of abDominal aortic aneurYsm (TEDY): The study protocol for a randomized controlled trial. Trials Morris, D. R., Cunningham, M. A., Ahimastos, A. A., Kingwell, B. A., Pappas, E., Bourke, M., Reid, C. M., Stijnen, T., Dalman, R. L., Aalami, O. O., Lindeman, J. H., Norman, P. E., Walker, P. J., Fitridge, R., Bourke, B., Dear, A. E., Pinchbeck, J., Jaeggi, R., Golledge, J. 2015; 16: 274-?

    Abstract

    Experimental studies suggest that angiotensin II plays a central role in the pathogenesis of abdominal aortic aneurysm. This trial aims to evaluate the efficacy of the angiotensin receptor blocker telmisartan in limiting the progression of abdominal aortic aneurysm.Telmisartan in the management of abdominal aortic aneurysm (TEDY) is a multicentre, parallel-design, randomised, double-blind, placebo-controlled trial with an intention-to-treat analysis. We aim to randomly assign 300 participants with small abdominal aortic aneurysm to either 40 mg of telmisartan or identical placebo and follow patients over 2 years. The primary endpoint will be abdominal aortic aneurysm growth as measured by 1) maximum infra-renal aortic volume on computed tomographic angiography, 2) maximum orthogonal diameter on computed tomographic angiography, and 3) maximum diameter on ultrasound. Secondary endpoints include change in resting brachial blood pressure, abdominal aortic aneurysm biomarker profile and health-related quality of life. TEDY is an international collaboration conducted from major vascular centres in Australia, the United States and the Netherlands.Currently, no medication has been convincingly demonstrated to limit abdominal aortic aneurysm progression. TEDY will examine the potential of a promising treatment strategy for patients with small abdominal aortic aneurysms.Australian and Leiden study centres: Australian New Zealand Clinical Trials Registry ACTRN12611000931976 , registered on 30 August 2011; Stanford study centre: clinicaltrials.gov NCT01683084 , registered on 5 September 2012.

    View details for DOI 10.1186/s13063-015-0793-z

    View details for PubMedID 26081587

    View details for PubMedCentralID PMC4482315

  • Targeting of Sp1 transcription factor: a novel therapeutic approach for Keloids, an in vitro analysis EXPERIMENTAL DERMATOLOGY Mukhopadhyay, A., Khoo, A., Cheong, H. H., Chan, S. Y., Aalami, O., Lim, I. J., Phan, T. T. 2007; 16 (12): 1023-1031

    Abstract

    Keloid scars are fibroproliferative disorders characterized by the accumulation of extracellular matrix (ECM) components resulting in a fibrotic condition. Several ECM promoters are regulated by Sp1. Thus, our aim was to investigate the role of Sp1 in keloid pathogenesis and investigate the antiproliferative and antifibrotic effects of Wp631 and mitoxantrone, potent inhibitors of Sp1-activated transcription. An elevated level of Sp1 was observed in tissue extracts obtained from keloid tissue. Serum stimulation elevated Sp1 levels in keloid fibroblasts (KF). Under coculture conditions Sp1 seemed to be downregulated. Wp631 and mitoxanthrone in serum growth factors resulted in a reduced expression of ECM components in KF. Both Wp631 and mitoxanthrone were also able to inhibit the proliferation of normal and keloid keratinocytes and fibroblasts significantly. As Wp631 seems to be potent in downregulating the ECM components in KF and also inhibiting the proliferation of these cells it could be explored as a possible therapeutic agent in the treatment of keloids.

    View details for DOI 10.1111/j.1600-0625.2007.00627.x

    View details for Web of Science ID 000251189300008

    View details for PubMedID 18031462

  • mTOR as a potential therapeutic target for treatment of keloids and excessive scars EXPERIMENTAL DERMATOLOGY Ong, C. T., Khoo, Y. T., Mukhopadhyay, A., Do, D. V., Lim, I. J., Aalami, O., Phan, T. T. 2007; 16 (5): 394-404

    Abstract

    Keloid is a dermal fibroproliferative disorder characterized by excessive deposition of extracellular matrix (ECM) components such as collagen, glycoproteins and fibronectin. The mammalian target of rapamycin (mTOR) is a serine/theronine kinase which plays an important role in the regulation of metabolic processes and translation rates. Published reports have shown mTOR as regulator of collagen expression and its inhibition induces a decrease in ECM deposition. Our aim was to investigate the role of mTOR in keloid pathogenesis and investigate the effect of rapamycin on proliferating cell nuclear antigen (PCNA), cyclin D1, collagen, fibronectin and alpha-smooth muscle actin (alpha-SMA) expression in normal fibroblasts (NF) and keloid fibroblasts (KF). Tissue extracts obtained from keloid scar demonstrated elevated expression of mTOR, p70KDa S6 kinase (p70S6K) and their activated forms, suggesting an activated state in keloid scars. Serum stimulation highlighted the heightened responsiveness of KF to mitogens and the importance of mTOR and p70S6K during early phase of wound healing. Application of rapamycin to monoculture NF and KF, dose- and time-dependently downregulates the expression of cytoplasmic PCNA, cyclin D1, fibronectin, collagen and alpha-SMA, demonstrating the anti-proliferative effect and therapeutic potential of rapamycin in the treatment of keloid scars. The inhibitory effect of rapamycin was found to be reversible following recovery in the expression of proteins following the removal of rapamycin from the culture media. These results demonstrate the important role of mTOR in the regulation of cell cycle and the expression of ECM proteins: fibronectin, collagen and alpha-SMA.

    View details for DOI 10.1111/j.1600-0625.2007.00550.x

    View details for Web of Science ID 000245605500002

    View details for PubMedID 17437482

  • Differential gene expression between juvenile and adult dura mater: A window into what genes play a role in the regeneration of membranous bone PLASTIC AND RECONSTRUCTIVE SURGERY Wan, D. C., Aalami, O. O., Wang, Z., Nacamuli, R. P., Lorget, F., Derynck, R., Longaker, M. T. 2006; 118 (4): 851-861

    Abstract

    Although reossification of large calvarial defects is possible in children, adults lack this tissue engineering capacity. In this study, the authors compared the differences in gene expression between juvenile and adult dura mater using a mouse cDNA microarray with 42,000 unique elements.Non-suture-associated parietal bone was harvested from 6-day-old and 60-day-old mice. The dura mater was carefully dissected from the calvarial disk and snap-frozen. RNA was extracted from pooled dura mater for microarray analysis. The 25 most differentially expressed genes were listed, as were selected bone-related genes. In addition, quantitative real-time reverse-transcriptase polymerase chain reaction confirmation of selected genes-BMP-2, BMP-4, and BMP-7; and osteopontin (OP), osteocalcin (OC), and FGFR-1-was performed.Juvenile dura mater expressed significantly greater amounts of BMP-2 and OP. Minimal difference in OC expression was observed between juvenile and adult dura mater. Extracellular matrix proteins (Col3a1, 5a1, 6a1, and fibronectin 1), osteoblast differentiation markers (Runx2/Cbfa1, Itm2a, and FGFR-1), and the growth factor Ptn were among other genes with greater expression in juvenile dura mater. Markers of osteoclasts (Acp5, MMP9, Ctsk) and the multiple candidate gene Ntrk2 were also expressed at higher levels in the juvenile dura mater.These findings suggest a more differentiated osteoprogenitor population to exist along with a greater presence of osteoclasts in the juvenile dura mater relative to adults. In addition to establishing a baseline difference in gene expression between juvenile and adult dura mater, new genes potentially critical to the regenerative potential of juvenile calvaria were identified.

    View details for DOI 10.1097/01.prs.0000232366.23897.2b

    View details for Web of Science ID 000240700100004

    View details for PubMedID 16980845

  • Effects of JAK3 inhibition with CP-690,550 on immune cell populations and their functions in nonhuman primate recipients of kidney allografts TRANSPLANTATION Paniagua, R., Si, M. S., Flores, M. G., Rousvoal, G., Zhang, S., Aalami, O., Campbell, A., Changelian, P. S., Reitz, B. A., Borie, D. C. 2005; 80 (9): 1283-1292

    Abstract

    Janus Kinase (JAK) 3 is a tyrosine kinase essential for proper signal transduction downstream of selected cytokine receptors and for robust T-cell and natural killer cells activation and function. JAK3 inhibition with CP-690,550 prevents acute allograft rejection. To provide further insight into the mechanisms of efficacy, we investigated the immunomodulatory effects of CP-690,550 in vitro and in vivo in nonhuman primates.Pharmacodynamic assessments of lymphocyte activation, function, proliferation and phenotype were performed in three settings: in vitro in whole blood isolated from untransplanted cynomolgus monkeys (cynos), in vivo in blood from untransplanted cynos dosed with CP-690,550 for 8 days, and in vivo in blood from transplanted cynos immunosuppressed with CP-690,550. Cell surface activation markers expression, IL-2- enhanced IFN-gamma production, lymphocyte proliferation and immune cell phenotype analyzes were performed with multiparametric flow cytometry.In vitro exposure to CP-690,550 resulted in significant reduction of IL-2-enhanced IFN-gamma production by T-cells (maximum inhibition of 55-63%), T-cell surface expression of CD25 (50% inhibitory concentration (IC50); 0.18 microM) and CD71 (IC50; 1.6 microM), and T-cell proliferative capacities measured by proliferating cell nuclear antigen expression (IC50; 0.87 microM). Similar results were observed in animals dosed with CP-690,550. In addition, transplanted animals displayed significant reduction of NK cell (90% from baseline) and T-cell numbers whereas CD8 effector memory T-cell populations were unaffected.Potent in vitro and in vivo immunomodulatory effects of the JAK3 inhibitor CP-690,550 likely contribute to its efficacy in the prevention of organ allograft rejection.

    View details for DOI 10.1097/01.tp.0000177643.05739.cd

    View details for Web of Science ID 000233732600021

    View details for PubMedID 16314797

  • Smad3 signalling plays an important role in keloid pathogenesis via epithelial-mesenchymal interactions JOURNAL OF PATHOLOGY Phan, T. T., Lim, I. J., Aalami, O., Lorget, F., Khoo, A., Tan, E. K., Mukhopadhyay, A., Longaker, M. T. 2005; 207 (2): 232-242

    Abstract

    Smad signalling plays important roles in developmental and cancer biology as well as in fibropathogenesis. Its role in keloid biology is not known. Epithelial-mesenchymal interactions, originally described in normal skin, have recently been established to play a significant role in keloid pathogenesis, and demonstrate the important influence of keratinocyte paracrine factor signalling on fibroblast behaviour. The present study investigated the role of downstream Smad cascade induction in this interaction. Normal fibroblasts (NF) and keloid fibroblasts (KF) were co-cultured in serum-free medium with normal keratinocytes (NK) or keloid keratinocytes (KK) for 5 days, after which fibroblast cell lysates were subjected to western blot and immunoprecipitation analysis to quantify the levels of Smad and Smad2/3/4 binding complex. In another set of experiments, wild-type (wt), Smad2-null (Smad2-/-) and Smad3-null (Smad3-/-) mouse embryonic fibroblasts (MEF) were assayed for cell proliferation and collagen production after serum-free co-culture with KK or exposure to conditioned media collected from serum-free KK/KF co-culture. Compared to normal skin, keloids expressed high basal levels of TGFbetaR1 and TGFbetaR2, Smad2, 3 and 4 and phospho-Smad2. Upregulation of TGFbetaR1 and TGFbetaR2, Smad3 and p-Smad2 was observed in KF co-cultured with KK, together with enhanced Smad3 phosphorylation and Smad2/3/4 binding complex production. When MEF-wt, MEF-Smad2-/- or MEF-Smad3-/- were co-cultured with KK or exposed to KK/KF co-culture conditioned media, enhanced proliferation and collagen production were seen in MEF-wt and MEF-Smad2-/- but not in MEF-Smad3-/- cells. The activation of Smad signalling, importantly that of Smad3, appears to be one facet of the complex epithelial-mesenchymal interactions in keloid pathogenesis, resulting in active KF proliferation and collagen-ECM production in co-culture with KK. This finding suggests the suppression of Smad signalling as a novel approach in keloid therapy.

    View details for DOI 10.1002/path.1826

    View details for Web of Science ID 000232213500012

    View details for PubMedID 16052471

  • Differential transcriptional expression profiles of juvenile and adult calvarial bone PLASTIC AND RECONSTRUCTIVE SURGERY Aalami, O. O., Nacamuli, R. P., Salim, A., Fong, K. D., Lenton, K. A., Song, H. M., Fang, T. D., Longaker, M. T. 2005; 115 (7): 1986-1994

    Abstract

    It has widely been observed that young children are capable of reossifying large calvarial defects, while adults lack this endogenous tissue-engineering capacity. The ability of juvenile animals to regenerate calvarial defects has been investigated in multiple animal models, including mice. In this study, the authors used cDNA microarrays to investigate the expression of osteogenesis-associated genes upstream and downstream of Runx2 in juvenile and adult mouse calvaria.Nonsuture-associated parietal bone discs were harvested from 6-day-old (n = 50) and 60-day-old (n = 35) male CD-1 mice. After separation of the underlying dura mater and overlying pericranium, the calvarial discs were snap-frozen and RNA was extracted from pooled samples of calvaria for microarray analysis. Genes analyzed included cytokines, receptors, and cell-surface and matrix proteins both upstream and downstream of Runx2.Genes associated with the Runx2 pathway had notably higher levels in the juvenile versus adult calvaria. All genes except for osteocalcin were expressed at least twofold higher in the juvenile calvaria. This pattern was validated with quantitative real-time polymerase chain reaction. In addition, mRNA for potent osteoinductive growth factors was present at higher levels in the juvenile compared with the adult calvaria.These findings reflect a genomic environment of active osteoblast differentiation and ossification in the juvenile calvaria compared with the adult "quiescent" calvarial tissue. These data suggest that a decreased osteogenic potential of adult calvarial osteoblasts may, in part, explain the inability of adult animals to heal calvarial defects.

    View details for DOI 10.1097/01.PRS.0000163323.66318.73

    View details for Web of Science ID 000229497700025

    View details for PubMedID 15923847

  • Bone morphogenetic protein 2 and retinoic acid accelerate in vivo bone formation, osteoclast recruitment, and bone turnover TISSUE ENGINEERING Cowan, C. M., Aalami, O. O., Shi, Y. Y., Chou, Y. F., Mari, C., Thomas, R., Quarto, N., Nacamuli, R. P., Contag, C. H., Wu, B., Longaker, M. T. 2005; 11 (3-4): 645-658

    Abstract

    Reconstruction of craniofacial defects presents a substantial biomedical burden, and requires complex surgery. Interestingly, children after age 2 years and adults are unable to heal large skull defects. This nonhealing paradigm provides an excellent model system for craniofacial skeletal tissueengineering strategies. Previous studies have documented the in vivo osteogenic potential of adipose-derived stromal (ADS) cells and bone marrow-derived stromal (BMS) cells. This study investigates the ability to accelerate in vivo osteogenesis on ex vivo recombinant human bone morphogenetic protein 2 (BMP-2) and retinoic acid stimulation. Mouse osteoblasts, ADS cells, and BMS cells were seeded onto apatite-coated PLGA scaffolds, stimulated with rhBMP-2 and retinoic acid ex vivo for 4 weeks, and subsequently implanted into critically sized (4 mm) calvarial defects. Samples were harvested after 2, 4, 8, and 12 weeks. Areas of complete bony bridging were noted as early as 2 weeks in vivo; however, osteoclasts were attracted to the scaffold as identified by calcitonin receptor staining and tartrate-resistant acid phosphatase activity staining. Although the optimal method of in vitro osteogenic priming for mesenchymal cells remains unknown, these results provide evidence that BMP-2 and retinoic acid stimulation of multipotent cells ex vivo can subsequently induce significant quantities of bone formation within a short time period in vivo.

    View details for PubMedID 15869441

  • Applications of a mouse model of calvarial healing: Differences in regenerative abilities of juveniles and adults PLASTIC AND RECONSTRUCTIVE SURGERY Aalami, O. O., Nacamuli, R. P., Lenton, K. A., Cowan, C. M., Fang, T. D., Fong, K. D., Shi, Y. Y., Song, H. M., Sahar, D. E., Longaker, M. T. 2004; 114 (3): 713-720

    Abstract

    Young children are capable of healing large calvarial defects, whereas adults lack this endogenous osseous tissue-engineering capacity. Despite the important clinical implications, little is known about the molecular and cell biology underlying this differential ability. Traditionally, guinea pig, rabbit, and rat models have been used to study the orchestration of calvarial healing. To harness the research potential of knockout and transgenic mice, the authors developed a mouse model for calvarial healing. Nonsuture-associated parietal defects 3, 4, and 5 mm in diameter were made in both juvenile (6-day-old, n = 15) and adult (60-day-old, n = 15) mice. Calvariae were harvested after 8 weeks and analyzed radiographically and histologically. Percentage of healing was quantified using Scion Image software analysis of calvarial radiographs. A significant difference in the ability to heal calvarial defects was seen between 6-day-old and 60-day-old mice when 3-, 4-, or 5-mm defects were created. The authors' analysis revealed that juvenile mice healed a significantly greater percentage of their calvarial defects than adult mice (juvenile mean percentage of healing: 3-mm defects, 59 percent; 4-mm defects, 65 percent; 5-mm defects, 44 percent; adult mean percentage of healing: <5 percent in all groups; p < 0.05). All three defect sizes were found to be critical in the adult, whereas significant healing was seen regardless of the size of the defect in juvenile mice. The establishment of this model will facilitate further, detailed evaluation of the molecular biology underlying the different regenerative abilities of juvenile versus adult mice and enhance research into membranous bone induction by making available powerful tools such as knockout and transgenic animals.

    View details for DOI 10.1097/01.PRS.0000131016.12754.30

    View details for Web of Science ID 000223436200015

    View details for PubMedID 15318051

  • Adipose-derived adult stromal cells heal critical-size mouse calvarial defects NATURE BIOTECHNOLOGY Cowan, C. M., Shi, Y. Y., Aalami, O. O., Chou, Y. F., Mari, C., Thomas, R., Quarto, N., Contag, C. H., Wu, B., Longaker, M. T. 2004; 22 (5): 560-567

    Abstract

    In adults and children over two years of age, large cranial defects do not reossify successfully, posing a substantial biomedical burden. The osteogenic potential of bone marrow stromal (BMS) cells has been documented. This study investigates the in vivo osteogenic capability of adipose-derived adult stromal (ADAS) cells, BMS cells, calvarial-derived osteoblasts and dura mater cells to heal critical-size mouse calvarial defects. Implanted, apatite-coated, PLGA scaffolds seeded with ADAS or BMS cells produced significant intramembranous bone formation by 2 weeks and areas of complete bony bridging by 12 weeks as shown by X-ray analysis, histology and live micromolecular imaging. The contribution of implanted cells to new bone formation was 84-99% by chromosomal detection. These data show that ADAS cells heal critical-size skeletal defects without genetic manipulation or the addition of exogenous growth factors.

    View details for DOI 10.1038/nbt958

    View details for PubMedID 15077117

  • Mechanisms of murine cranial suture patency mediated by a dominant negative transforming growth factor-beta receptor adenovirus PLASTIC AND RECONSTRUCTIVE SURGERY Song, H. J., Fong, D., Nacamuli, R. P., Warren, S. M., Fang, T. D., Mathy, J. A., Cowan, C. M., Aalami, O. O., Longaker, M. T. 2004; 113 (6): 1685-1697

    Abstract

    Using a physiologic model of mouse cranial suture fusion, the authors' laboratory has previously demonstrated that transforming growth factor (TGF)-betas appear to be more abundantly expressed in the suture complex of the fusing posterior frontal compared with the patent sagittal suture. Furthermore, the authors have shown that by blocking TGF-beta signaling with a replication-deficient adenovirus encoding a defective, dominant negative type II TGF-beta receptor (AdDN-TbetaRII), posterior frontal suture fusion was inhibited. In this study, the authors attempt to further elucidate the role of TGF-beta in cranial suture fusion by investigating possible mechanisms of AdDN-TbetaRII-mediated cranial suture patency using both an established organ culture model and a novel in vitro co-culture system that recapitulates the in vivo anatomic dura mater/cranial suture relationship. In this article, the authors demonstrate that blocking TGF-beta signaling with the AdDN-TbetaRII construct led to inhibition of cellular proliferation in the suture mesenchyme and subjacent dura mater during the early period of predicted posterior frontal suture fusion. Interestingly, co-culture experiments revealed that transfecting osteoblasts with AdDN-TbetaRII led to alterations in the gene expression levels of two important bone-related molecules (Msx2 and osteopontin). Inhibiting TGF-beta signaling prevented time-dependent suppression of Msx2 and prevented induction of osteopontin, thereby retarding osteoblast differentiation. Furthermore, the authors demonstrated that the AdDN-TbetaRII construct was capable of blocking TGF-beta -mediated up-regulation of collagen IalphaI, an extracellular matrix molecule important for bone formation. Collectively, these data strongly suggest that AdDN-TbetaRII maintains posterior frontal patency, in part by altering early events in de novo bone formation, including cellular proliferation and early extracellular matrix production.

    View details for DOI 10.1097/001.PRS.000117363.43699.5B

    View details for Web of Science ID 000221141000019

    View details for PubMedID 15114130

  • In vitro murine posterior frontal suture fate is age-dependent: Implications for cranial suture biology PLASTIC AND RECONSTRUCTIVE SURGERY Song, H. J., Sahar, D. E., Fong, K. D., Nacamuli, R. P., Fang, T. D., Mathy, J. A., Aalami, O. O., Warren, S. M., Longaker, M. T. 2004; 113 (4): 1192-1204

    Abstract

    In CD-1 mice, the posterior frontal suture (analogous to the human metopic suture) fuses while all other cranial sutures remain patent. In an in vitro organ culture model, the authors previously demonstrated that posterior frontal sutures explanted immediately before the onset of suture fusion (at 25 days old) mimic in vivo physiologic fusion. In the first portion of this study, the authors defined how early in development the posterior frontal suture fuses in their tension-free, serum-free organ culture system by serially analyzing posterior frontal suture fusion from calvariae explanted at different stages of postnatal development. Their results revealed a divergence of suture fate leading to abnormal patency or physiologic fusion between the first and second weeks of life, respectively, despite viability and continued growth of the calvarial explants in vitro. From these data, the authors postulated that the gene expression patterns present in the suture complex at the time of explant may determine whether the posterior frontal suture fuses or remains patent in organ culture. Therefore, to elucidate potentially important differences in gene expression within this "window of opportunity," they performed a cDNA microarray analysis on 5-day-old and 15-day-old posterior frontal and sagittal whole suture complexes corresponding to the age ranges for unsuccessful (1 to 7 days old) and successful (14 to 21 days old) in vitro posterior frontal suture fusion. Overall, their microarray results reveal interesting differential expression patterns of candidate genes in different categories, including angiogenic cytokines and mechanosensitive genes potentially important in cranial suture biology.

    View details for DOI 10.1097/01.PRS.0000110203.90911.63

    View details for Web of Science ID 000220618600011

    View details for PubMedID 15083020

  • Postoperative rhabdomyolysis following laparoscopic gastric bypass in the morbidly obese ARCHIVES OF SURGERY Khurana, R. N., Baudendistel, T. E., Morgan, E. F., Rabkin, R. A., Elkin, R. B., Aalami, O. O. 2004; 139 (1): 73-76

    Abstract

    Laparoscopic approaches for weight reduction in the morbidly obese have become common with more than 50,000 bariatric surgical procedures being performed in 2001. The objective of this article is to raise awareness among surgeons of a new complication of rhabdomyolysis from this frequent procedure.Case series extracted from surgical database from January 2, 2001, through December 31, 2002.We identified 5 cases of postoperative rhabdomyolysis in morbidly obese patients who underwent laparoscopic duodenal switch procedures with parietal gastrectomy. The cause, pathogenesis, and clinical features are reviewed and discussed.Postoperative rhabdomyolysis developed in 5 of 353 morbidly obese patients who underwent consecutive laparoscopic duodenal switch procedures, an incidence of 1.4%. All 5 patients were male, had a mean peak serum creatine kinase level of 19 680 U/L, and reported muscle pain in either the buttock, hip, or shoulder regions during the early postoperative period.We hypothesized that morbidly obese patients develop critical surface and deep tissue pressures during bariatric surgery, increasing their risk for tissue injury and rhabdomyolysis. Unexplained elevations in the serum creatinine level or reports of buttock, hip, or shoulder pain in the postoperative period should raise the possibility of rhabdomyolysis and prompt clinical investigation. We recommend routine preoperative and postoperative measurements of the serum creatine kinase and serum creatinine levels to aid detection. Surgeons need to keep a low index of suspicion because early diagnosis and treatment are the cornerstones of successful management of rhabdomyolysis.

    View details for Web of Science ID 000187998500017

    View details for PubMedID 14718280

  • Physiological features of aging persons ARCHIVES OF SURGERY Aalami, O. O., Fang, T. D., Song, H. M., Nacamuli, R. P. 2003; 138 (10): 1068-1076

    View details for Web of Science ID 000186075900006

    View details for PubMedID 14557122

  • Roles of periosteum, dura, and adjacent bone on healing of cranial osteonecrosis - Discussion JOURNAL OF CRANIOFACIAL SURGERY Aalami, O. O., Nacamuli, R. P., Longaker, M. T. 2003; 14 (3): 380-382
  • A mouse model of mandibular distraction osteogenesis 10th International Congress of the International-Society-of-Craniofacial-Surgery Fang, T. D., Nacamuli, R. P., Song, H. M., Thomas, R., Fong, K. D., Aalami, O. O., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 397–398
  • Microarray analysis of regional patterning of suture-specific dura mater 10th International Congress of the International-Society-of-Craniofacial-Surgery Nacamuli, R. P., Song, H. M., Fang, T. D., Fong, K. D., Aalami, O. O., Salim, A., Sahar, D. E., Chi, J. T., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 459–460
  • Establishment of a young-versus-adult mouse calvarial defect model 10th International Congress of the International-Society-of-Craniofacial-Surgery Aalami, O. O., Nacamuli, R. P., Fong, K. D., Fang, T. D., Song, H. M., Sahar, D. E., Lenton, K. A., Cowan, C. M., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 375–377
  • Analysis of de novo bone formation by dura-derived TGF-beta signaling 10th International Congress of the International-Society-of-Craniofacial-Surgery Song, H. M., Nacamuli, R. P., Fong, K. D., Fang, T. D., Aalami, O. A., Warren, S. M., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 489–491
  • The osteogenic antagonist BMP-3 is down-regulated during programmed suture fusion in the rat 10th International Congress of the International-Society-of-Craniofacial-Surgery Fong, K. D., Nacamuli, R. P., Lenton, K., Fang, T. D., Song, H. M., Salim, A., Shi, Y. Y., Aalami, O. O., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 399–401
  • Microarray analysis comparing juvenile and adult dura mater 10th International Congress of the International-Society-of-Craniofacial-Surgery Aalami, O. O., Fong, K. D., Nacamult, R. P., Fang, T. D., Song, H. M., Sahar, D. E., Lenton, K. A., Cowan, C. M., Chi, J. T., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 373–374
  • Cranial suture fate in an in vitro organ culture model 10th International Congress of the International-Society-of-Craniofacial-Surgery Sahar, D. E., Song, H. M., Fong, K. D., Nacamuli, R. P., Warren, S. M., Mathy, J. A., Fang, T. D., Aalami, O., Longaker, M. T. MEDIMOND PUBLISHING CO. 2003: 473–475