Anthony F Firek

Prof. Anthony F Firek

1. Comparative Effectiveness and Clinical Outcomes Research Center (CECORC), Riverside University Health System, Moreno Valley, CA 92555, USA
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Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 February 2022 in Nutrients
Verified
Journal Article
Open access
PDF file
ADAlfonso Manuel Durán
Alfonso Manuel Durán
LBLarry Beeson
Larry Beeson
AFAnthony F Firek
Anthony F Firek
ZCZaida Cordero-MacIntyre
Zaida Cordero-MacIntyre
MLMarino De Leon
Marino De Leon
Background: Omega-3 polyunsaturated fatty acids (PUFAs) have been proposed to improve chronic neuroinflammatory diseases in peripheral and central nervous systems. For instance, docosahexaenoic acid (DHA) protects nerve cells from noxious stimuli in vitro and in vivo. Recent reports link PUFA supplementation to improving painful diabetic neuropathy (pDN) symptoms, but cellular mechanisms responsible for this therapeutic effect are not well understood. The objective of this study is to identify distinct cellular pathways elicited by dietary omega-3 PUFA supplementation in patients with type 2 diabetes mellitus (T2DM) affected by pDN. Methods: Forty volunteers diagnosed with type 2 diabetes were enrolled in the “En Balance-PLUS” diabetes education study. The volunteers participated in weekly lifestyle/nutrition education and daily supplementation with 1000 mg DHA and 200 mg eicosapentaenoic acid. The Short-Form McGill Pain Questionnaire validated clinical determination of baseline and post-intervention pain complaints. Laboratory and untargeted metabolomics analyses were conducted using blood plasma collected at baseline and after three months of participation in the dietary regimen. The metabolomics data were analyzed using random forest, hierarchical clustering, ingenuity pathway analysis, and metabolic pathway mapping. Results: The data show that metabolites involved in oxidative stress and glutathione production shifted significantly to a more anti-inflammatory state post supplementation. Example of these metabolites include cystathionine (+90%), S-methylmethionine (+9%), glycine cysteine-glutathione disulfide (+157%) cysteinylglycine (+19%), glutamate (−11%), glycine (+11%), and arginine (+13.4%). In addition, the levels of phospholipids associated with improved membrane fluidity such as linoleoyl-docosahexaenoyl-glycerol (18:2/22:6) (+253%) were significantly increased. Ingenuity pathway analysis suggested several key bio functions associated with omega-3 PUFA supplementation such as formation of reactive oxygen species (p = 4.38 × 10−4, z-score = −1.96), peroxidation of lipids (p = 2.24 × 10−5, z-score = −1.944), Ca2+ transport (p = 1.55 × 10−4, z-score = −1.969), excitation of neurons (p = 1.07 ×10−4, z-score = −1.091), and concentration of glutathione (p = 3.06 × 10−4, z-score = 1.974). Conclusion: The reduction of pro-inflammatory and oxidative stress pathways following dietary omega-3 PUFA supplementation is consistent with the promising role of these fatty acids in reducing adverse symptoms associated with neuroinflammatory diseases and painful neuropathy.

9 October 2021 in Vaccines
Verified
Journal Article
Open access
PDF file
NGNicole M Gatto
Nicole M Gatto
JLJerusha E. Lee
Jerusha E. Lee
DMDonatella Massai
Donatella Massai
SZSusanna Zamarripa
Susanna Zamarripa
BSBijan Sasaninia
Bijan Sasaninia
AFAnthony F Firek
Anthony F Firek
Since health professionals provide frontline care to COVID-19 patients, information on vaccine acceptance among healthcare workers is needed. We developed and implemented an anonymous internet-based cross-sectional survey with direct solicitation among employees of a safety net health system. Items queried demographic and health-related characteristics, experience with and knowledge of COVID-19, and determinants of decisions to vaccinate. COVID-19 vaccine acceptance groups (acceptors, hesitant, refusers) were defined; an adapted version of the WHO vaccine hesitancy scale was included. The survey demonstrated good reliability (Cronbach’s alpha = 0.92 for vaccine hesitancy scale; 0.93 for determinants). General linear and logistic regression methods examined factors which were univariately associated with vaccine hesitancy and vaccine acceptance, respectively. Multivariable models were constructed with stepwise model-building procedures. Race/ethnicity, marital status, job classification, immunocompromised status, flu vaccination and childhood vaccination opinions independently predicted hesitancy scale scores. Gender, education, job classification and BMI independently predicted acceptance, hesitancy, and refusal groups. Among hesitant employees, uncertainty was reflected in reports of motivating factors influencing their indecision. Despite a strong employee-support environment and job protection, respondents reported physical and mental health effects. The appreciation of varied reasons for refusing vaccination should lead to culturally sensitive interventions to increase vaccination rates amongst healthcare workers.

18 December 2023 in Vaccines
Verified
Journal Article
Open access
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Béla DénesBéla Dénes
Béla Dénes
RFRyan N. Fuller
Ryan N. Fuller
WKWayne Kelin
Wayne Kelin
TLTessa R. Levin
Tessa R. Levin
JGJaipuneet Gil
Jaipuneet Gil
WLWilliam H.R. Langridge
William H.R. Langridge
Mucosal vaccines protect against respiratory virus infection by stimulating the production of IgA antibodies that protect against virus invasion of the mucosal epithelium. In this study, a novel protein subunit mucosal vaccine was constructed for protection against infection by the beta coronavirus SARS-CoV-2. The vaccine was assembled by linking a gene encoding the SARS-CoV-2 virus S1 angiotensin converting enzyme receptor binding domain (ACE-2-RBD) downstream from a DNA fragment encoding the cholera toxin B subunit (CTB), a mucosal adjuvant known to stimulate vaccine immunogenicity. A 42 kDa vaccine fusion protein was identified in homogenates of transformed E. coli BL-21 cells by acrylamide gel electrophoresis and by immunoblotting against anti-CTB and anti-ACE-2-RBD primary antibodies. The chimeric CTB-SARS-CoV-2-ACE-2-RBD vaccine fusion protein was partially purified from clarified bacterial homogenates by nickel affinity column chromatography. Further vaccine purification was accomplished by polyacrylamide gel electrophoresis and electro-elution of the 42 kDa chimeric vaccine protein. Vaccine protection against SARS-CoV-2 infection was assessed by oral, nasal, and parenteral immunization of BALB/c mice with the CTB-SARS-CoV-2-ACE-2-RBD protein. Vaccine-induced SARS-CoV-2 specific antibodies were quantified in immunized mouse serum by ELISA analysis. Serum from immunized mice contained IgG and IgA antibodies that neutralized SARS-CoV-2 infection in Vero E6 cell cultures. In contrast to unimmunized mice, cytological examination of cell necrosis in lung tissues excised from immunized mice revealed no detectable cellular abnormalities. Mouse behavior following vaccine immunization remained normal throughout the duration of the experiments. Together, our data show that a CTB-adjuvant-stimulated CTB-SARS-CoV-2-ACE-2-RBD chimeric mucosal vaccine protein synthesized in bacteria can produce durable and persistent IgA antibodies in mice that neutralize the SARS-CoV-2 subvariant Omicron BA.1.1.

13 December 2023 in Current Oncology
Verified
Journal Article
Open access
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KRKristiana Rood
Kristiana Rood
CYCelina Romi Yamauchi
Celina Romi Yamauchi
USUmang Sharma
Umang Sharma
RLRia Laxa
Ria Laxa
CRCollin Robins
Collin Robins
SKSalma Khan
Salma Khan
Enigma protein, encoded by the PDLIM7 gene, is overexpressed in thyroid cancer in a stage-dependent manner, suggesting a potential involvement in the initiation and progression of thyroid cancer. The Enigma interacts with several cellular pathways, including PI3K/AKT, MDM2, and BMP-1. The Enigma is regulated by microRNAs. Specifically, we showed that the Enigma protein upregulation corresponds to the downregulation of Let-7 family genes. There is limited research on the interactions and regulation of the Enigma with other proteins/genes in thyroid cancer tissues, indicating a gap in current knowledge. Our aim is to establish the Enigma as a biomarker. We also aim to study the interacting partners of the Enigma signaling pathways and their probable miRNA regulation in thyroid cancer progression. Using Western blotting, densitometric analysis, immunoprecipitation (IP), and reverse IP, we detected the protein expression and protein–protein interactions in the corresponding papillary thyroid carcinomas (PTCs). Utilizing real-time qPCR assay and Pearson’s correlation test, we highlighted the correlation between PDLIM7 and Let-7g gene expression in the same tissues. The results showed the differential upregulations of the Enigma protein in different stages of PTCs compared to benign tissues along with AKT, VDR, BMP-1, and MDM2 proteins. Loss of DBP was observed in a subset of PTCs. Strong interactions of the Enigma with PI3K/AKT and MDM2 were noted, along with a weaker BMP-1 interaction. Pearson’s correlation coefficient analysis between PDLIM7 and let-7g gene expression was significant (p < 0.05); however, there was a weak inverse correlation (r = −0.27). The study suggests the potential utility of the PDLIM7-qPCR assay as a biomarker for thyroid cancer. The Enigma’s interactions with key signaling pathways may provide valuable insights into the development of thyroid cancer. The study contributes to understanding the molecular mechanisms involving the Enigma protein in thyroid cancer and highlights its potential as a biomarker.

3 August 2022 in Vaccines
Verified
Journal Article
Open access
PDF file
Lauren Alyssa GarciaLauren Alyssa Garcia
Lauren Alyssa Garcia
AFAnthony F Firek
Anthony F Firek
DFDeborah Anne Freund
Deborah Anne Freund
DMDonatella Massai
Donatella Massai
DKDhruv Khurana
Dhruv Khurana
NGNicole M Gatto
Nicole M Gatto
Background: Limited information exists regarding COVID-19 vaccine hesitancy among healthcare workers (HCWs). Our previous survey analyzed the reasons for HCWs’ decisions to accept vaccination, suggesting that a “one-size fits all” approach may not suffice to increase vaccine uptake. Methods: Based on the vaccination acceptance group (acceptor, hesitant, refuser), we examined differences by sociodemographic factors (race/ethnicity, household income, education) from Likert Scale responses to fourteen influences affecting a decision to be vaccinated using the Kruskal–Wallis test and multinomial logistic regression with mutual adjustment for these sociodemographic factors, age, and sex. Results: Non-Hispanic White vaccine acceptors ranked lower confidence in preventing, withstanding, or treating COVID-19, while Non-Hispanic Blacks more highly regarded the motivation of a religious leader, colleague, or family member. Social media was ranked more influential among Non-Hispanic Asians. Acceptors with lower incomes ranked a job requirement influential; conversely, higher income vaccine hesitant HCWs highly rated this reason. More highly educated acceptors ranked being motivated by colleagues, family, and other HCWs higher. Adjustment weakened some but not all the differences between groups. Conclusions: Sociodemographic factors affect HCWs’ decisions to be vaccinated against COVID-19. Our findings may help develop more focused and tailored strategies to improve vaccination acceptance.

26 August 2026 in Preprints.org
Verified
Preprint
Open access
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NRNazia Rahman
Nazia Rahman
ALAlex Lim
Alex Lim
SCSteven Chrysafides
Steven Chrysafides
RTRuchi Trivedi
Ruchi Trivedi
JSJonathan Scott
Jonathan Scott
AFAnthony F Firek
Anthony F Firek
Background: Inappropriate thyroid ultrasound (TUS) ordering by primary care providers (PCPs) is documented at academic centers but not in safety-net populations serving predominantly Hispanic patients. Objective: To quantify non-guideline TUS ordering, identify independent predictors, characterize indication-level concordance, and assess the association between guideline adherence and downstream diagnostic interventions. Design: Retrospective observational study (STROBE-compliant). Setting: Outpatient primary care clinics of a public safety-net hospital in Moreno Valley, California. Participants: 405 adults and children (age 7–86 years) who underwent PCP-ordered thyroid ultrasound between March 2023 and March 2024. Inpatient, specialist-ordered, and specialist-recommended TUS were excluded. Measurements: ATA guideline concordance (primary outcome) documented directed thyroid physical examination (PE), ICD-10 indication, and downstream outcomes (FNA, Bethesda cytology, thyroidectomy, pathology). Multivariable logistic regression, chi-square, and Fisher exact tests were used. Results: Of 405 orders, 178 (44.0%) were non-guideline. Patients were predominantly Hispanic (68.6%) and female (89.1%). Absence of directed PE independently predicted non-guideline ordering (OR, 4.67; 95% CI, 2.61–8.36; p< 0.001). Thyrotoxicosis/hyperthyroid and compressive-symptom indications had OR >38 versus nodule/follow-up. Biochemical indications had 95–100% non-guideline rates. Guideline-concordant TUS produced higher FNA rates (26.0% vs. 10.7%; p< 0.001) and 2.8-fold more Bethesda III–VI findings. Among 14 thyroidectomies, 71.4% occurred in patients without documented PE. Limitations: Single-center retrospective design; PE documentation may underestimate actual examination; causality cannot be established. Conclusion: Non-guideline TUS ordering is common in safety-net primary care, driven by biochemical indications and PE omission. Guideline-concordant TUS yields greater diagnostic value; targeted education and decision-support are needed.