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Dive into the research topics where Antonia Valenzuela is active.

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Featured researches published by Antonia Valenzuela.


JAMA Dermatology | 2014

Identification of clinical features and autoantibodies associated with calcinosis in dermatomyositis

Antonia Valenzuela; Lorinda Chung; Livia Casciola-Rosen; David Fiorentino

IMPORTANCE Prior studies have estimated that up to 20% of adults with dermatomyositis (DM) have calcinosis, which can lead to significant morbidity. Identification of risk factors may provide a better understanding of the pathogenesis and ultimately therapy for this difficult clinical problem. Risk factors for calcinosis in adults with DM have not been extensively studied. OBJECTIVES To determine the prevalence of calcinosis and to identify associated clinical features in a cohort of extensively phenotyped adults with DM. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional study of 126 patients diagnosed as having DM from January 1, 2006, through January 1, 2013, was performed. Patients were adults (≥18 years of age) attending the Stanford University Medical Center clinic. MAIN OUTCOMES AND MEASURES Calcinosis, defined as the presence of calcium deposition in the skin and subcutaneous tissues on physical examination. RESULTS Fourteen patients (11.1%) had calcinosis, with the extremities most commonly involved. Patients with vs those without calcinosis had a longer disease duration (median, 6.9 years; range, 2.4-18.1; vs median, 3.9 years; range, 0.2-19.2 years; P = .003) and more fingertip ulcers (50.0% vs 9.3%, P < .001). An association between calcinosis and both interstitial lung disease and anti-MDA-5 autoantibodies was identified, but this association did not persist in multivariate models that adjusted for fingertip ulcers. Fingertip ulcers and disease duration were strongly associated with calcinosis in all multivariate models, independent of the underlying autoantibody present. Autoantibodies to NXP-2 were associated with calcinosis (odds ratio, 15.52; 95% CI, 2.01-119.90), whereas anti-transcriptional intermediary factor 1-γ antibodies were protective (odds ratio, 0.2; 95% CI, 0.01-0.99) in multivariate analyses that adjusted for fingertip ulcers and other covariates. CONCLUSIONS AND RELEVANCE Calcinosis was a relatively uncommon clinical feature in our cohort of adults with DM. Our data suggest that calcinosis is positively associated with longer disease duration, fingertip ulcers, and NXP-2 autoantibodies and negatively associated with transcriptional intermediary factor 1-γ antibodies. A common vascular mechanism may underlie the development of both calcinosis and fingertip ulcers in patients with DM.


Clinical Gastroenterology and Hepatology | 2012

Incidence of hepatocellular carcinoma among US patients with cirrhosis of viral or nonviral etiologies.

Robert Mair; Antonia Valenzuela; Nghiem B. Ha; Walid Ayoub; Tami Daugherty; Glen Lutchman; Gabriel Garcia; Aijaz Ahmed; Mindie H. Nguyen

BACKGROUND & AIMS We aimed to identify risk factors for hepatocellular carcinoma (HCC) in patients with cirrhosis in the United States. We performed a prospective study to identify associations between etiologies of cirrhosis and ethnicity with HCC incidence. METHODS We used convenience sampling to select a cohort of 379 patients with cirrhosis who visited the liver clinic at the Stanford University Medical Center from 2001 to 2009 (65% male, 75% white or Hispanic, and 20% Asian). Study end points were HCC diagnosis by histology or noninvasive criteria, liver transplantation, or last screening without HCC. Patients were followed up, with ultrasound or computed tomographic imaging analyses and measurements of serum levels of α-fetoprotein, approximately every 6 months, for a median time of 34 months (range, 6-99 mo). RESULTS The etiologies of cirrhosis in the cohort were 68% hepatitis C, 7% hepatitis B, and 25% nonviral. Forty-four patients (12%) were diagnosed with HCC during the follow-up period. Patients with cirrhosis related to viral hepatitis had a statistically significantly higher incidence of HCC than those with nonviral diseases in Kaplan-Meier analysis (P = .04). There was no statistically significant difference in HCC incidence between Asian and non-Asian patients. In a multivariate Cox proportional hazards model that included age, sex, ethnicity, etiology, and Child-Pugh-Turcotte score, viral cirrhosis was associated significantly with HCC, compared with nonviral cirrhosis (hazard ratio, 3.6; 95% confidence interval, 1.3-10.1; P = .02) but Asian ethnicity was not. CONCLUSIONS In a diverse cohort of patients in the United States with cirrhosis, a viral etiology of cirrhosis was associated with increased incidence of HCC, but Asian ethnicity was not. These findings indicate the importance of cirrhosis etiology in determining risk for HCC.


Hypertension | 2015

Leukotriene B4 Activates Pulmonary Artery Adventitial Fibroblasts in Pulmonary Hypertension.

Jin Qian; Wen Tian; Xinguo Jiang; Rasa Tamosiuniene; Yon K. Sung; Eric M. Shuffle; Allen B. Tu; Antonia Valenzuela; Shirley Jiang; Roham T. Zamanian; David Fiorentino; Norbert F. Voelkel; Marc Peters-Golden; Kurt R. Stenmark; Lorinda Chung; Marlene Rabinovitch; Mark R. Nicolls

A recent study demonstrated a significant role for leukotriene B4 (LTB4) causing pulmonary vascular remodeling in pulmonary arterial hypertension. LTB4 was found to directly injure luminal endothelial cells and promote growth of the smooth muscle cell layer of pulmonary arterioles. The purpose of this study was to determine the effects of LTB4 on the pulmonary adventitial layer, largely composed of fibroblasts. Here, we demonstrate that LTB4 enhanced human pulmonary artery adventitial fibroblast proliferation, migration, and differentiation in a dose-dependent manner through its cognate G-protein–coupled receptor, BLT1. LTB4 activated human pulmonary artery adventitial fibroblast by upregulating p38 mitogen-activated protein kinase as well as Nox4-signaling pathways. In an autoimmune model of pulmonary hypertension, inhibition of these pathways blocked perivascular inflammation, decreased Nox4 expression, reduced reactive oxygen species production, reversed arteriolar adventitial fibroblast activation, and attenuated pulmonary hypertension development. This study uncovers a novel mechanism by which LTB4 further promotes pulmonary arterial hypertension pathogenesis, beyond its established effects on endothelial and smooth muscle cells, by activating adventitial fibroblasts.


Microsurgery | 2015

Surgical treatment of systemic sclerosis--is it justified to offer peripheral sympathectomy earlier in the disease process?

Arash Momeni; Sarah C. Sorice; Antonia Valenzuela; David Fiorentino; Lorinda Chung; James Chang

Systemic sclerosis (SSc) is a rare connective tissue disease associated with significant digital vasculopathy. Peripheral sympathectomy is frequently offered late in the disease process after severe digital ischemia has already occurred with patients being symptomatic for numerous years. The purpose of the present study was to analyze the results of peripheral sympathectomy in patients with a confirmed diagnosis of SSc.


JCI insight | 2016

Integrated, multicohort analysis of systemic sclerosis identifies robust transcriptional signature of disease severity

Shane Lofgren; Monique Hinchcliff; Mary Carns; Tammara A. Wood; Kathleen Aren; Esperanza Arroyo; Peggie Cheung; Alex J. Kuo; Antonia Valenzuela; Anna Haemel; Paul J. Wolters; Jessica K. Gordon; Robert Spiera; Shervin Assassi; Francesco Boin; Lorinda Chung; David Fiorentino; Paul J. Utz; Michael L. Whitfield; Purvesh Khatri

Systemic sclerosis (SSc) is a rare autoimmune disease with the highest case-fatality rate of all connective tissue diseases. Current efforts to determine patient response to a given treatment using the modified Rodnan skin score (mRSS) are complicated by interclinician variability, confounding, and the time required between sequential mRSS measurements to observe meaningful change. There is an unmet critical need for an objective metric of SSc disease severity. Here, we performed an integrated, multicohort analysis of SSc transcriptome data across 7 datasets from 6 centers composed of 515 samples. Using 158 skin samples from SSc patients and healthy controls recruited at 2 centers as a discovery cohort, we identified a 415-gene expression signature specific for SSc, and validated its ability to distinguish SSc patients from healthy controls in an additional 357 skin samples from 5 independent cohorts. Next, we defined the SSc skin severity score (4S). In every SSc cohort of skin biopsy samples analyzed in our study, 4S correlated significantly with mRSS, allowing objective quantification of SSc disease severity. Using transcriptome data from the largest longitudinal trial of SSc patients to date, we showed that 4S allowed us to objectively monitor individual SSc patients over time, as (a) the change in 4S of a patient is significantly correlated with change in the mRSS, and (b) the change in 4S at 12 months of treatment could predict the change in mRSS at 24 months. Our results suggest that 4S could be used to distinguish treatment responders from nonresponders prior to mRSS change. Our results demonstrate the potential clinical utility of a novel robust molecular signature and a computational approach to SSc disease severity quantification.


Seminars in Arthritis and Rheumatism | 2016

Calcinosis is associated with digital ulcers and osteoporosis in patients with Systemic Sclerosis: A Scleroderma Clinical Trials Consortium Study

Antonia Valenzuela; Murray Baron; Ariane L. Herrick; Susanna Proudman; W. Stevens; Tatiana S. Rodriguez-Reyna; Alessandra Vacca; Thomas A. Medsger; Monique Hinchcliff; Vivien M. Hsu; Joy Y. Wu; David Fiorentino; Lorinda Chung

OBJECTIVES We sought to identify the clinical factors associated with calcinosis in an international multicenter collaborative effort with the Scleroderma Clinical Trials Consortium (SCTC). METHODS This is a retrospective cohort study of 5218 patients with systemic sclerosis (SSc). Logistic regression was used to obtain odds ratios (OR) relating calcinosis to various clinical features in multivariate analyses. RESULTS A total of 1290 patients (24.7%) had calcinosis. In univariate analyses, patients with calcinosis were older than patients without calcinosis, more likely to be female, and had longer disease duration from the first non-Raynaud phenomenon symptom. Patients with calcinosis were more likely to have digital ulcers, telangiectasias, acro-osteolysis, cardiac disease, pulmonary hypertension, gastrointestinal involvement, arthritis, and osteoporosis, but less likely to have muscle disease. Anti-Scl-70, RNA-polymerase-III, and U1-RNP autoantibodies were significantly less common in patients with calcinosis, while anticentromere (ACA), anti-PM/Scl, and anticardiolipin antibodies were more frequent. In multivariate analysis, the strongest associations with calcinosis were digital ulcers (OR = 3.9; 95% CI: 2.7-5.5; p < 0.0001) and osteoporosis (OR = 4.2; 95% CI: 2.3-7.9; p < 0.0001). CONCLUSION One quarter of patients with SSc have calcinosis at some time during their illness. Our data confirm a strong association of calcinosis with digital ulcers, and support a novel association with osteoporosis.


Arthritis Care and Research | 2015

Validation of a Novel Radiographic Scoring System for Calcinosis Affecting the Hands of Patients With Systemic Sclerosis

Lorinda Chung; Antonia Valenzuela; David Fiorentino; Kathryn J. Stevens; Shufeng Li; Jonathan Harris; Charles E. Hutchinson; Shervin Assassi; Lorenzo Beretta; Santhanam Lakshminarayanan; Tatiana S. Rodriguez-Reyna; Christopher P. Denton; Rebecca Taillefer; Ariane L. Herrick; Murray Baron

There are currently no validated outcome measures to assess calcinosis severity in systemic sclerosis (SSc; scleroderma). We sought to develop and validate a novel radiographic scoring system for calcinosis affecting the hands of SSc patients for potential use in future clinical trials.


Rheumatology | 2016

Intestinal pseudo-obstruction in patients with systemic sclerosis: an analysis of the Nationwide Inpatient Sample

Antonia Valenzuela; Shufeng Li; Laren Becker; Nielsen Q. Fernandez-Becker; Dinesh Khanna; Linda Nguyen; Lorinda Chung

OBJECTIVE Intestinal pseudo-obstruction is a rare gastrointestinal complication in patients with SSc without large studies examining its prevalence or outcomes. We aimed to compare outcomes in SSc patients with intestinal pseudo-obstruction to patients with intestinal pseudo-obstruction secondary to other causes, and SSc patients without intestinal pseudo-obstruction. METHODS This is a case-control study using the Healthcare Cost and Utilization Project Nationwide Inpatient Sample for the period 2002-2011. We included patients with the previously validated International Classification of Diseases-Clinical Modification-9 code 710.1 for SSc in combination with codes for intestinal pseudo-obstruction, and determined length of hospitalization and the risks for surgical procedures, use of total parenteral nutrition (TPN) and in-hospital mortality. RESULTS A total of 193 610 SSc hospitalizations occurred in the USA between 2002 and 2011, of which 5.4% (n = 10 386) were associated with a concurrent intestinal pseudo-obstruction diagnosis (cases). In-hospital mortality was 7.3%. In multivariate analyses, cases were more likely to die during the inpatient stay and to receive TPN than patients with idiopathic intestinal pseudo-obstruction (control group 1), patients with intestinal pseudo-obstruction and diabetes (control group 2), and SSc patients without intestinal pseudo-obstruction (control group 3). Cases had longer in-hospital stay than control groups 2 and 3, and were less likely to undergo surgical procedures than control groups 1 and 2. CONCLUSION Intestinal pseudo-obstruction is a rare cause of hospitalization in patients with SSc, but is associated with high in-hospital mortality in comparison with other SSc patients and those with intestinal pseudo-obstruction secondary to other causes.


Rheumatic Diseases Clinics of North America | 2015

Monitoring and Diagnostic Approaches for Pulmonary Arterial Hypertension in Patients with Systemic Sclerosis

Antonia Valenzuela; Saranya Nandagopal; Virginia D. Steen; Lorinda Chung

Pulmonary arterial hypertension (PAH) is one of the leading causes of death in patients with systemic sclerosis (SSc). Given the high prevalence and poor survival of SSc-PAH, and that aggressive management of mild disease may be associated with better outcomes, screening is critical. Right heart catheterization (RHC) is the gold standard for the definitive diagnosis of PAH, and should be performed in those patients in whom this diagnosis is suspected. Once a diagnosis of PAH is confirmed by RHC, treatment with PAH-specific therapies should be initiated as soon as possible.


Scandinavian Journal of Rheumatology | 2015

Validation of the ICD-9-CM code for systemic sclerosis using updated ACR/EULAR classification criteria

Antonia Valenzuela; Aaliya Yaqub; David Fiorentino; Eswar Krishnan; Lorinda Chung

There are currently three sets of classification criteria most commonly used to identify systemic sclerosis (SSc): the 1980 American College of Rheumatology (ACR) criteria (1), the CREST (calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) criteria (2), and the 2013 revised ACR/ European League Against Rheumatism (EULAR) criteria (3). The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code 710.1 is often used for research purposes to identify patients with SSc, but its accuracy has not been clearly determined (4). We sought to validate the ICD-9-CM code 710.1 for identifying cases of SSc who met any of the above classification criteria. We conducted a longitudinal retrospective study of all adult patients evaluated at Stanford Hospital Clinics from December 2005 to October 2012 who had an associated ICD-9-CM code of 710.1. We determined the positive

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