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Open Access Publications from the University of California

Scholarly Works (198 results)

  • Thesis
  • Peer Reviewed
UCLA Electronic Theses and Dissertations (2019)

Background: The melanoma-associated antigen-A (MAGE-A) and program-death ligand 1 (PD-L1) are present in urothelial carcinoma (UC). We aim to assess survival outcomes in patients with MAGE-A and PD-L1 expression.

Methods: Analysis of MAGE-A and PD-L1 expression on neoplastic cells was conducted using tissue microarrays from patients with UC. We compared differential expression between stage and grade. Co-expression of MAGE-A and PD-L1 were sub-categorized. Fisher’s exact test was done for categorical variables followed by analysis of univariable and multivariable assessment of recurrence and progression free survival (RFS, PFS).

Results: Co-expression of MAGE+/PD-L1+ had a higher expression in advanced disease, however only MAGE+/PD-L1- group was associated with shorter RFS (HR 1.89, 95%CI 1.19-2.99; p=0.006). MAGE+/PD-L1+ was associated with the worst PFS (HR 17.1, 95%CI 5.96-49.4; p=<0.001). MAGE-A expression was more prevalent high-grade (p=0.015), and higher stage ≥pT2 (p=0.001). The 5-year RFS in MAGE+ was 44%vs.58% for MAGE- samples. On multivariable analysis MP was also associated with shorter recurrence (HR 1.55, 95%CI 1.05-2.30; p=0.03). Similarly, MAGE+ was associated with shorter PFS (HR 3.12, 95%CI 1.12-8.68; p=0.03).

Conclusion: We report that the expression of MAGE-A and PD-L1 is increased in more advanced disease and associated with shorter PFS. Furthermore, expression of MAGE-A is significant in higher grade and stage, and was associated with shorter RFS and PFS. The finding of worse prognosis of MAGE-A/PD-L1 provides early evidence that a potential combinatorial treatment strategy of co-targeting MAGE/PD-L1 with respective agents might be feasible. Further studies are needed to validate these findings.

    Cover page: Association of Melanoma-Associated Antigen-A and Program-death ligand 1 Expression and Clinical Outcomes in Urothelial Carcinoma
    • Thesis
    • Peer Reviewed
    UCLA Electronic Theses and Dissertations (2013)

    Multiple techniques exist to target nerves that transmit pain due to facet arthropathy, however no study has demonstrated a superior technique. This retrospective cohort study identified patients who underwent lumbar facet denervation, analyzing each patient's treatment technique, Modified Shealy versus Australian, as well as benefit. Pre-and post-procedural visual numeric scale (VNS) scores, and VNS score changes between the two groups showed no differences (p = 0.72, 0.06, 0.08). Patient reported benefit and duration of relief was greater in the Australian group (p = 0.012, 0.022). Male gender and no pain medication use at baseline was associated with decreased post-ablation VNS scores, while increasing age and higher pre-ablation VNS scores was associated with increased post-ablation VNS scores. Increasing age and the Australian technique conferred greater treatment benefit. The results of this study indicate superiority of the Australian over the Modified Shealy technique for the treatment of lumbar facet pain.

      Cover page: A Retrospective Comparison of the Modified Shealy Technique versus the Australian Technique for The Treatment of Lumbar Facet Arthropathy
      • Thesis
      • Peer Reviewed
      UCLA Electronic Theses and Dissertations (2015)

      Background: Candidates may be active or temporarily inactive (status 7) on the kidney transplant waiting list. One reason candidates may be inactive is for a “weight currently inappropriate for transplantation”. We hypothesized that many of these candidates would not achieve active status.

      Methods: Using OPTN/UNOS data from 2006-2012, we used competing risks methods to determine the cumulative incidence of conversion to active status (activation), death, and delisting before conversion among 1679 obese adult kidney candidates designated as status 7 due to a weight inappropriate for transplantation. Fine and Gray competing risks regression was performed to characterize factors associated with conversion to active status in the overall study population and of eventual transplantation among a subgroup of activated candidates.

      Results: At six years, the cumulative incidence of activation was 49%, of death before conversion was 15%, and of delisting was 21%. Higher body mass index (BMI) was strongly associated with a decreased subhazard of activation (BMI ≥45 vs. 30-34.9, sHR: 0.22; 95% CI: 0.16-0.33). Female gender, diabetic end-stage renal disease, history of a previous transplant, panel reactive antibodies <80%, dialysis-dependence at listing, and UNOS region 5 were negatively associated with activation. Among activated candidates, the cumulative incidence of transplantation at six years after initial waitlisting was 61%.

      Conclusions: Our findings indicate that half of obese status 7 candidates with a weight inappropriate for transplantation will not achieve active waitlist status. BMI at listing had a strong association with conversion to active status; however, co-morbid factors and regional variation also impact activation.

        Cover page: Incidence of Conversion to Active Waitlist Status Among Temporarily Inactive Obese Renal Transplant Candidates
        • Thesis
        • Peer Reviewed
        UCLA Electronic Theses and Dissertations (2022)

        INTRODUCTION: Maternal body composition may influence fetal/neonatal body composition.OBJECTIVE: To investigate the relationship between maternal and fetal body composition. METHODS: Three cohorts of women were studied: healthy mothers, mothers with gestational diabetes (GDM), and otherwise healthy mothers with a growth-restricted fetus (FGR). MRI measured quantitative traits of maternal body composition (visceral adipose tissue volume (VAT), subcutaneous adipose tissue volume (SAT), pancreatic and hepatic proton-density fat fraction (PDFF)) and fetal body composition (abdominal SAT and hepatic PDFF). RESULTS: GDM fetuses had greater SAT volume than FGR fetuses and greater hepatic PDFF than FGR (280 [261, 295] vs. 220 [205, 235] mm3) and healthy fetuses (GDM 5.2 [4.2, 5.5]%, FGR 1.9 [1.4, 3.7]%, healthy 3.2 [3, 3.3]%). Fetal hepatic PDFF was associated with maternal SAT (r=0.47, p=0.02), VAT (r=0.62, p=0.002), and pancreatic PDFF (r=0.54, p=0.008). Fetal SAT was associated with infant birth weight z-scores (r=0.48, p=0.02). CONCLUSION: In this study, maternal adiposity and GDM status were associated with fetal hepatic fat.

          Cover page: Pregnancies Complicated by Gestational Diabetes and Fetal Growth Restriction: Fetal and Maternal Body Composition
          • Article
          • Peer Reviewed
          UCLA Previously Published Works (2019)
          Multiple studies have shown a Mediterranean diet, characterized by their olive oil and nut consumption, to be correlated with lower depression risk. To examine whether part of this reduced risk in the United States is attributable to walnut consumption, we analyzed data on walnut consumption and depression scores from the National Health and Nutrition Examination Survey (NHANES). NHANES survey data for 2005 through 2014 was pooled for adults with 24 h recall dietary data. Depression scores were based on PHQ-9 self-report responses. A total of 26,656 participants were characterized as reporting the consumption of walnuts with high certainty, walnuts with other nuts, other nuts, or no nuts. After an adjustment for covariates, walnut consumers showed lower depression scores compared to non-nut consumers. The least square mean for total depression score was 26% lower for walnut with high certainty consumers than for non-nut consumers (p < 0.0001), and the association was stronger among women (32%, p < 0.0001) than men (21%, p = 0.05). The significant contributors to this difference were due to walnut consumers reporting greater interest in doing things (p = 0.003), less hopelessness (p = 0.02), and feeling more energetic (p = 0.05) than non-nut consumers. Non-nut consumers were more likely to have trouble concentrating (p = 0.02), to feel they were moving or speaking abnormally (p = 0.03), and to have thought they were better off dead (p = 0.002). Depression scores were significantly lower among nut consumers and particularly walnut consumers as compared to non-nut consumers. After controlling for potential covariates, walnut users had scores significantly lower than other nut consumers. The difference was strongest among women, who are more likely than men to report higher depression scores.
            Cover page: Lower Depression Scores among Walnut Consumers in NHANES.
            • Thesis
            • Peer Reviewed
            UCLA Electronic Theses and Dissertations (2016)

            Surgical patients age 65 and over face a high risk of cardiac complications. The Revised Cardiac Risk Index (RCRI) and the Gupta Myocardial Infarction or Cardiac Arrest (MICA) are widely used to predict perioperative cardiac risk but they are not specifically designed to predict that risk in geriatric patients. The objective of this study is to develop and validate a geriatric-sensitive cardiac risk index (GSCRI). Three variables were selected using Lasso regression in the National Surgical Quality Improvement Program (NSQIP) 2013 with the addition of four clinically significant variables. The model was developed using the NSQIP 2013 geriatric cohort (N=485,426) (172,905 age ≥ 65) and validated on the NSQIP 2012 geriatric cohort (N=485,426) (210,914 age ≥ 65). The Area under the Curve (AUC) for the NSQIP 2012 geriatric cohort for three indices was compared. Gupta MICA had an AUC of 0.70 and the RCRI had an AUC of 0.63. Our GSCRI model showed better performance with an AUC of 0.76

              Cover page: The Derivation and Validation of a Geriatric-Sensitive Perioperative Cardiac Risk Index (GSCRI)
              • Article
              • Peer Reviewed
              UCLA Previously Published Works (2021)

              Background

              Evidence is limited as to whether the introduction of the Affordable Care Act (ACA)'s Medicaid expansions was associated with improvements in cardiovascular risk factors at the population level.

              Objective

              To examine the association between the ACA Medicaid expansions and changes in cardiovascular risk factors among low-income individuals during the first 3 years of the implementation of the ACA Medicaid expansions at the national level.

              Design

              A quasi-experimental difference-in-differences (DID) analysis to compare outcomes before (2005-2012) and after (2015-2016) the implementation of the ACA Medicaid expansions between individuals in states that expanded Medicaid and individuals in non-expansion states.

              Participants

              A nationally representative sample of individuals aged 19-64 years with family incomes below 138% of the federal poverty level from the 2005-2016 National Health and Nutrition Examination Survey (NHANES).

              Intervention

              ACA Medicaid expansions.

              Main measures

              Cardiovascular risk factors included (1) systolic and diastolic blood pressure, (2) hemoglobin A1c (HbA1c) level, and (3) cholesterol levels (low-density lipoprotein cholesterol, triglyceride, and high-density lipoprotein cholesterol).

              Key results

              A total of 9177 low-income individuals were included in our analysis. We found that the ACA Medicaid expansions were associated with a lower systolic blood pressure (DID estimate, - 3.03 mmHg; 95% CI, - 5.33 mmHg to - 0.73 mmHg; P = 0.01; P = 0.03 after adjustment for multiple comparisons) and lower HbA1c level (DID estimate, - 0.14 percentage points [pp]; 95% CI, - 0.24 pp to - 0.03 pp; P = 0.01; P = 0.03 after adjustment for multiple comparisons). We found no evidence that diastolic blood pressure and cholesterol levels changed following the ACA Medicaid expansions.

              Conclusion

              Using the nationally representative data of individuals who were affected by the ACA, we found that the ACA Medicaid expansions were associated with a modest improvement in cardiovascular risk factors related to hypertension and diabetes during the first 3 years of implementation.
                Cover page: Association Between the ACA Medicaid Expansions and Changes in Cardiovascular Risk Factors Among Low-Income Individuals.
                • Article
                • Peer Reviewed
                UC Irvine Previously Published Works (2014)
                Most patients with Alzheimer's disease (AD) do not have a spouse. Despite this, the majority of AD research participants enroll with a spouse study partner. It remains unclear if differences between AD patients who do and do not have a spouse may bias study results. In this study, we examined whether AD patients with different study partner types (spouse versus adult child) demonstrate different rates of disease progression over two years on three outcome measures commonly used in AD research, including clinical trials. We used data from the National Alzheimer's Coordinating Center Uniform Data Set to examine disease progression in participants age 55-90 with probable AD dementia. We examined disease progression as measured by the Clinical Dementia Rating Scale-Sum of the Boxes score, the Mini Mental Status Examination, and the Functional Assessment Questionnaire. Analyses were performed on data for all available eligible participants from the NACC UDS and after performing a propensity-matching model to better account for inherent differences between the populations of interest. Propensity matching was successful only when models did not include age and gender. For both propensity-matched analyses and those of all available data, we did not observe any differences between the study partner populations for any outcome measure. These results suggest that if investigators can improve in recruiting AD patients with adult child caregivers to research, the implications to study results may be minimal.
                  Cover page: Does Study Partner Type Impact the Rate of Alzheimer's Disease Progression?Creative Commons 'BY' version 4.0 license
                  • Article
                  • Peer Reviewed
                  UC Irvine Previously Published Works (2013)
                  Using a novel noninvasive, visible-light optical diffusion oximeter (T-Stat VLS Tissue Oximeter; Spectros Corporation, Portola Valley, CA) to measure the tissue oxygen saturation (StO2) of the buccal mucosa, the correlation between StOz and central venous oxygen saturation (ScvO2) was examined in children with congenital cyanotic heart disease undergoing a cardiac surgical procedure. Paired StO2 and serum ScvO2 measurements were obtained postoperatively and statistically analyzed for agreement and association. Thirteen children (nine male) participated in the study (age range, 4 days to 18 months). Surgeries included Glenn shunt procedures, Norwood procedures, unifocalization procedures with Blalock-Taussig shunt placement, a Kawashima/ Glenn shunt procedure, a Blalock-Taussig shunt placement, and a modified Norwood procedure. A total of 45 paired StO2-ScvO2 measurements was obtained. Linear regression demonstrated a Pearson's correlation of .58 (95% confidence interval [CI], .35-.75; p < .0001). The regression slope coefficient estimate was .95 (95% CI, .54-1.36) with an interclass correlation coefficient of .48 (95% CI, .22-.68). Below a clinically relevant average ScvO2 value, a receiver operator characteristic analysis yielded an area under the curve of .78. Statistical methods to control for repeatedly measuring the same subjects produced similar results. This study shows a moderate relationship and agreement between StO2 and ScvO2 measurements in pediatric patients with a history of congenital cyanotic heart disease undergoing a cardiac surgical procedure. This real-time monitoring device can act as a valuable adjunct to standard noninvasive monitoring in which serum SyvO2 sampling currently assists in the diagnosis of low cardiac output after pediatric cardiac surgery.
                    Cover page: Correlation of a novel noninvasive tissue oxygen saturation monitor to serum central venous oxygen saturation in pediatric patients with postoperative congenital cyanotic heart disease.
                    • Article
                    • Peer Reviewed
                    UC Irvine Previously Published Works (2013)
                    To identify the facilitators and barriers to preclinical Alzheimer's disease (AD) clinical trial recruitment, 50 cognitively normal participants were interviewed after being randomized to one of two hypothetical AD risk scenarios: (1) the general age-related risk for AD, or (2) being at 50% increased risk for AD. Participants provided uncued barriers and facilitators to the hypothetical decision of whether they would enroll. Thirteen themes of facilitators and five themes of barriers were identified. The most common barrier was fear related to taking study drug. Those randomized to being at increased risk for AD more frequently cited lowering personal risk as a facilitator (P = .01) and less frequently cited time as a barrier to enrollment (P = .02). These results suggest potential challenges to preclinical AD clinical trial recruitment and that disclosing risk information may enhance enrollment.
                      Cover page: Risk disclosure and preclinical Alzheimer's disease clinical trial enrollmentCreative Commons 'BY' version 4.0 license
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