Browsing by Author "Fan, Hao"

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    Associations between Intake of Calcium, Magnesium, and Phosphorus and Risk of Pancreatic Cancer: A Population-Based, Case-Control Study in Minnesota
    (Cambridge UP, 2021) Fan, Hao; Yu, Yunpeng; Nan, Haocheng; Hoyt, Margaret; Reger, Michael K.; Prizment, Anna; Anderson, Kristin E.; Zhang, Jianjun; Epidemiology, School of Public Health
    Experimental studies suggest that abnormal levels of calcium, magnesium, and phosphorus are implicated in pancreatic carcinogenesis. We investigated the associations between intakes of these minerals and the risk of pancreatic cancer in a case-control study conducted in 1994-1998. Cases of pancreatic cancer (n150) were recruited from all hospitals in the metropolitan area of the Twin Cities and Mayo Clinic, Minnesota. Controls (n459) were randomly selected from the general population and frequency matched to cases by age, sex, and race. All dietary variables were adjusted for energy intake using the residual method prior to data analysis. Logistic regression was performed to evaluate the associations between intake of three nutrients examined and the risk of pancreatic cancer. Total intake of calcium (936 vs. 1026 mg/day) and dietary intake of magnesium (315 vs. 331 mg/day) and phosphorus (1350 vs. 1402 mg/day) were significantly lower in cases than in controls. After adjustment for confounders, there were not significant associations of total and dietary intakes of calcium, magnesium, and phosphorus with the risk of pancreatic cancer. In addition, no significant interactions exist between intakes of these minerals and total fat on pancreatic cancer risk. In conclusion, the present study does not suggest that intakes of calcium, magnesium, and phosphorus were significantly associated with the risk of pancreatic cancer.
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    Behavior and health beliefs as predictors of HIV testing among women: a prospective study of observed HIV testing
    (Taylor & Francis, 2018) Fan, Hao; Fife, Kenneth H.; Cox, Dena; Cox, Anthony D.; Zimet, Gregory D.; Pediatrics, School of Medicine
    Much of the research examining predictors of HIV testing has used retrospective self-report to assess HIV testing. Findings. therefore, may be subject to recall bias and to difficulties determining the direction of associations. In this prospective study, we administered surveys to women in community clinics to identify predictors of subsequent observed HIV testing, overcoming these limitations. Eighty-three percent were tested. In the adjusted multivariable model, being born in the U.S., perceived benefits of testing, worries about being infected with HIV, having had more than 15 lifetime sexual partners, and having had one or more casual sexual partners in the previous three months predicted acceptance of testing. Perceived obstacles to testing predicted non-acceptance. Those who had never been tested for HIV and those tested two to five years previously had greater odds of test acceptance than those who had been tested within the last year. The findings from this study with observed testing as the outcome, confirm some of the results from retrospective, self-report studies. Participants made largely rational decisions about testing, reflecting assessments of their risk and their history of HIV testing. Health beliefs are potentially modifiable through behavioral intervention, and such interventions might result in greater acceptance of testing.
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    Circulating Leptin and Branched Chain Amino Acids – Correlation with Intraductal Papillary Mucinous Neoplasm Dysplastic Grade
    (Springer Verlag, 2019-05) Yip-Schneider, Michele T.; Simpson, Rachel; Carr, Rosalie A.; Wu, Huangbing; Fan, Hao; Liu, Ziyue; Korc, Murray; Zhang, Jianjun; Schmidt, C. Max; Surgery, School of Medicine
    Background: The most common type of mucinous pancreatic cyst that may progress to pancreatic cancer is intraductal papillary mucinous neoplasm (IPMN). Low-risk IPMN with low-/moderate-grade dysplasia may be safely watched, whereas high-risk IPMN with high-grade dysplasia or invasive components should undergo resection. However, there is currently no reliable means of making this distinction. We hypothesize that blood concentrations of insulin resistance biomarkers may aid in the differentiation of low- and high-risk IPMN. Methods: Plasma/serum was collected from consented patients undergoing pancreatic resection. IPMN diagnosis and dysplastic grade were confirmed by surgical pathology. The study included 235 IPMN (166 low/moderate grade, 39 high grade, 30 invasive). Circulating levels of leptin, branched chain amino acids (BCAA), and retinol-binding protein-4 (RBP-4) were measured by enzyme-linked immunoassay and correlated with surgical pathology. Results: Circulating leptin levels (mean ± SE) were significantly higher in patients with low/moderate IPMN than in high-grade/invasive IPMN (15,803 ± 1686 vs. 10,275 ± 1228 pg/ml; p = 0.0086). Leptin levels were positively correlated with BMI (r = 0.65, p < 0.0001) and were higher in females (p < 0.0001). Stratified analysis showed that mean leptin levels were significantly different between low/moderate and high/invasive IPMNs only in females (24,383 ± 2748 vs. 16,295 ± 2040 pg/ml; p = 0.020). Conversely, circulating BCAA levels were lower in low/moderate IPMN than in high-grade/invasive IPMN (0.38 ± 0.007 vs. 0.42 ± 0.01 mM; p = 0.011). No significant differences in RBP-4 levels were observed. Conclusions: Circulating leptin in females and BCAA correlates with IPMN dysplastic grade and, if combined with clinical characteristics, have the potential to improve clinical decision-making.
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    Circulating Thrombospondin-2 enhances prediction of malignant intraductal papillary mucinous neoplasm
    (Elsevier, 2018) Simpson, Rachel E.; Yip-Schneider, Michele T.; Wu, Huangbing; Fan, Hao; Liu, Ziyue; Korc, Murray; Zhang, Jianjun; Schmidt, C. Max; Surgery, School of Medicine
    Background IPMNs are cystic pancreatic lesions with variable malignant potential. Thrombospondin-2 (THBS2)—an endogenous, anti-angiogenic matrix glycoprotein—may modulate tumor progression. We hypothesized that circulating levels of THBS2 could aid in preoperative prediction of malignant IPMN. Methods Preoperative serum/plasma samples were procured from patients undergoing surgery. Circulating levels of THBS2 were measured (enzyme-linked immunosorbent assay) and compared to surgical pathology IPMN dysplastic grade. Results 164 patients underwent THBS2 testing (100 Low/Moderate-IPMN; 64 High-Grade/Invasive-IPMN). Circulating THBS2 (mean ± SD) was greater in High-Grade/Invasive-IPMN than Low/Moderate-grade IPMN (26.6 ± 12.7 ng/mL vs. 20.4 ± 8.2 ng/mL; P < 0.001). THBS2 (AUC = 0.65) out-performed CA19-9 (n = 144; AUC = 0.59) in predicting IPMN grade. The combination of THBS2, CA19-9, radiographic main-duct involvement, main-duct diameter, age, sex, and BMI (AUC 0.82; n = 137) provided a good prediction model for IPMN grade. Conclusion Circulating THBS2 is correlated with IPMN dysplasia grade. THBS2 alone did not strongly predict IPMN grade but rather strengthened prediction models for High-Grade/Invasive IPMN when combined with other clinical/biomarker data.
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    Intake of methyl-related nutrients and risk of pancreatic cancer in a population-based case-control study in Minnesota
    (Springer Nature, 2018-08) Marley, Andrew R.; Fan, Hao; Hoyt, Margaret L.; Anderson, Kristin E.; Zhang, Jianjun; Epidemiology, School of Public Health
    BACKGROUND/OBJECTIVES: Folate, vitamin B6, vitamin B12, and methionine are involved in DNA synthesis and methylation and thus may modulate pancreatic cancer risk. We investigated these associations in a population-based case-control study conducted in 1994-1998. SUBJECTS/METHODS: Cases (n = 150) were identified from all hospitals in the metropolitan areas of the Twin Cities and the Mayo Clinic, Minnesota. Controls (n = 459) were selected randomly from the general population and were frequency matched to cases by age, sex, and race. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for risk of pancreatic cancer in relation to intake of nutrients considered. RESULTS: Dietary intake of folate was associated with a reduced pancreatic cancer risk [OR (95% CI) for quartile (Q) 4 vs. Q1: 0.31 (0.12-0.78)]. A composite score (range from 2 to 8), reflecting combined dietary intake of folate and vitamin B6, was also inversely associated with pancreatic cancer risk [OR (95% CI) for Q4 vs. Q1: 0.24 (0.08-0.70)]. Null associations were found for intake of vitamin B12 and methionine. CONCLUSIONS: Dietary folate intake was associated with a reduced pancreatic cancer risk, and this association became stronger when dietary intake of folate and vitamin B6 was combined in analysis.
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    A National County-Level Assessment of U.S. Nursing Facility Characteristics Associated with Long-Term Exposure to Traffic Pollution in Older Adults
    (2018-03) Wang, Yi; Fan, Hao; Banerjee, Aniruddha; Weaver, Anne M.; Weiner, Michael
    Long-term exposure to ambient air pollution increases disease risk in older adults. Nursing facilities located near major roadways potentially expose older adults to traffic pollution. No studies, however, have described the association between nursing facilities and traffic pollution. We obtained data on facility- and census-tract-level characteristics of 15,706 U.S. facilities from the Medicare Nursing Home Compare datasets. We calculated distance to major roadways and traffic density for each facility. In the contiguous U.S. (as of 2014), 345,792 older adults, about 27% of residents in non-hospital facilities, lived within 150 m major roadways (A1 or A2) in 3876 (28% of sampled) facilities. Nationally, for-profit facilities, high-occupancy facilities, and facilities in census tracts with higher percentages of minorities were more likely to have higher exposure to traffic. Counties in Virginia, New York City, and Rhode Island have the highest percent of residents and facilities near major roads. Nationally, over one-quarter of sampled facilities are located near major roadways. Attributes potentially associated with higher exposure to traffic included “for-profit” and “higher minority census tract”. Proximity to major roadways may be an important factor to consider in siting nursing facilities. Our results inform potential intervention strategy at both county and facility level.
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    The spatial distribution and temporal variation of desert riparian forests and their influencing factors in the downstream Heihe River basin, China
    (2017) Ding, Jingyi; Zhao, Wenwu; Daryanto, Stefani; Wang, Lixin; Fan, Hao; Feng, Qiang; Wang, Yaping; Earth Science, School of Science
    Desert riparian forests are the main restored vegetation community in Heihe River basin. They provide critical habitats and a variety of ecosystem services in this arid environment. Since desert riparian forests are also sensitive to disturbance, examining the spatial distribution and temporal variation of these forests and their influencing factors is important to determine the limiting factors of vegetation recovery after long-term restoration. In this study, field experiment and remote sensing data were used to determine the spatial distribution and temporal variation of desert riparian forests and their relationship with the environmental factors. We classified five types of vegetation communities at different distances from the river channel. Community coverage and diversity formed a bimodal pattern, peaking at the distances of 1000 and 3000 m from the river channel. In general, the temporal normalized difference vegetation index (NDVI) trend from 2000 to 2014 was positive at different distances from the river channel, except for the region closest to the river bank (i.e. within 500 m from the river channel), which had been undergoing degradation since 2011. The spatial distribution of desert riparian forests was mainly influenced by the spatial heterogeneity of soil properties (e.g. soil moisture, bulk density and soil particle composition). Meanwhile, while the temporal variation of vegetation was affected by both the spatial heterogeneity of soil properties (e.g. soil moisture and soil particle composition) and to a lesser extent, the temporal variation of water availability (e.g. annual average and variability of groundwater, soil moisture and runoff). Since surface (0–30 cm) and deep (100–200 cm) soil moisture, bulk density and the annual average of soil moisture at 100 cm obtained from the remote sensing data were regarded as major determining factors of community distribution and temporal variation, conservation measures that protect the soil structure and prevent soil moisture depletion (e.g. artificial soil cover and water conveyance channels) were suggested to better protect desert riparian forests under climate change and intensive human disturbance.