Publications

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Problems with memory, executive function, and language are a significant public health issue, especially when they begin during midlife. However, there is relatively little work on risk and protective factors for cognitive function in middle adulthood. Using data from 883 Mexican-origin adults assessed up to 6 times across 12 years (Meanage at

Faculty Member

Problems with memory, executive function, and language are a significant public health issue, especially when they begin during midlife. However, there is relatively little work on risk and protective factors for cognitive function in middle adulthood. Using data from 883 Mexican-origin adults assessed up to 6 times across 12 years (Meanage at

Faculty Member

Some people use healthcare services more than others. Identifying factors associated with healthcare use has the potential to improve the effectiveness, efficiency, and equity of healthcare. In line with the Andersen behavioral model of healthcare utilization and initial empirical findings, personality traits may be key predisposing factors

Research Area
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Objective

One large focus of personality psychology is to understand the biopsychosocial factors responsible for adult personality development and well-being change. However, little is known about how macro-level contextual factors, such as rurality–urbanicity, are related to personality development and well-being change.

Method

The present study uses data from two large longitudinal studies of U.S. Americans (MIDUS, HRS) to examine whether there are rural–urban differences in levels and changes in the Big Five personality traits and well-being (i.e., psychological well-being, and life satisfaction) in adulthood.

Results

Multilevel models showed that Americans who lived in more rural areas tended to have lower levels of openness, conscientiousness, and psychological well-being, and higher levels of neuroticism. With the exception of psychological well-being (which replicated across MIDUS and HRS), rural–urban differences in personality traits were only evident in the HRS sample. The effect of neuroticism was fully robust to the inclusion of socio-demographic and social network covariates, but other effects were partially robust (i.e., conscientiousness and openness) or were not robust at all (i.e., psychological well-being). In both samples, there were no rural–urban differences in Big Five or well-being change.

Conclusions

We discuss the implications of these findings for personality and rural health research.

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This study reports the first clinical evidence of significantly high secretion of matrine in a multi-component botanical (Antitumor B, ATB) into human saliva from the systemic circulation. This is of high clinical significance as matrine can be used as a monitoring tool during longitudinal clinical studies to overcome the key limitation of poor patient compliance often reported in cancer chemoprevention trials. Both matrine and dictamine were detected in the saliva and plasma samples but only matrine was quantifiable after the oral administration of ATB tablets (2400 mg) in 8 healthy volunteers. A significantly high saliva/plasma ratios for Cmax (6.5 ± 2.0) and AUC0–24 (4.8 ± 2.0) of matrine suggested an active secretion in saliva probably due to entero-salivary recycling as evident from the long half-lives (t1/2 plasma = 10.0 ± 2.8 h, t1/2 saliva = 13.4 ± 6.9 h). The correlation between saliva and plasma levels of matrine was established using a population compartmental pharmacokinetic co-model. Moreover, a species-relevant PBPK model was developed to adequately describe the pharmacokinetic profiles of matrine in mouse, rat, and human. In conclusion, matrine saliva concentrations can be used as an excellent marker compound for mechanistic studies of active secretion of drugs from plasma to saliva as well as monitor the patient’s compliance to the treatment regimen in upcoming clinical trials of ATB.

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Gut microbial β-glucuronidase (gmGUS) is involved in the disposition of many endogenous and exogenous compounds. Preclinical studies have shown that inhibiting gmGUS activity affects drug disposition, resulting in reduced toxicity in the gastrointestinal tract (GIT) and enhanced systemic efficacy. Additionally, manipulating gmGUS activity is expected to be effective in preventing/treating local or systemic diseases. Although results from animal studies are promising, challenges remain in developing drugs by targeting gmGUS. Here, we review the role of gmGUS in host health under physiological and pathological conditions, the impact of gmGUS on the disposition of phenolic compounds, models used to study gmGUS activity, and the perspectives and challenges in developing drugs by targeting gmGUS.

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Irinotecan is a first-line treatment for colorectal cancer and the prodrug of 7-ethyl-10-hydroxy-camptothecin (SN-38). However, its fatal gastrointestinal (GI) toxicity raises serious concern. In liver, irinotecan generates its inactive metabolite, SN-38G via UDP-glucuronosyltransferase (UGT)1A1. Subsequently, SN-38G is excreted into GI tract where it is reactivated by microbiome to yield the toxic metabolite, SN-38. Activation of toll-like receptor (TLR)/myeloid differentiation primary response 88 (MyD88) by bacterial endotoxin decreases drug-metabolizing enzymes. In this study, we treated C57BL6/J mice with 50 mg/kg irinotecan once daily until observing grade 4 diarrhea. Mice were sacrificed on day0, day2 and day8. Based on the finding in C57BL6/J mice, we repeated the treatment in Tlr2-/-Tlr4-/- and Myd88-/- mice to determine the impact of inflammation on UGT metabolism. Our toxicity study in C57BL6/J mice …

Research documents how identity linked processes may have important health implications for people with marginalized or stigmatized identities. While previous work suggests that certain dimensions of identity may moderate the impact of minority stressors to wellbeing, work on identity centrality has yielded mixed findings about the directionality of the relationship between centrality and health. Given the importance of identity centrality on self-concept, this study highlights how differential exposure to minority stressors matters for identity construction. Drawing from 25 in-depth interviews on Black and Latino/a sexual minority adults, I examine perceptions of identity centrality and exposure to minority stressors. There are three key findings to highlight. First, results present evidence of intra-group variability in identity centrality. Second, results indicate that differential exposure to minority stress matters for perceptions of identity centrality. Finally, results note that differentiating between stigma and race related stressors is necessary to better understand experiences of minority stress.

Although evidence indicates that identity centrality, or identity importance, can serve as a positive coping mechanism regarding well-being, less is known if it can also buffer against health risk behaviors like cigarette smoking. This study uses an intercategorical intersectional approach using data from 1,571 Black and Latino/a sexual and gender minority adults in the Social Justice Sexuality Project to assess the relationship between sexual and racial and ethnic identity centrality and smoking patterns. Relative risk ratios from multinomial logistic regressions highlight three findings. First, there is no evidence of a significant association between identity centrality and smoking behavior nor evidence of a significant interaction effect between racial and ethnic and sexual identity centrality. Once models were adjusted for education, the association between centrality and smoking was no longer significant. Second, results indicate that education, gender identity, familial support and outness were significant predictors of smoking behaviors. Third, results suggest that there are significant differences across the intersection of race and ethnicity and sexual identity in relative risk of smoking. In addition, findings highlight elevated risk of engaging in more casual behaviors of smoking as opposed to heightened smoking behavior among both Black and Latino/a sexual minority adults.

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Purpose

In this mixed-methods study, we address two aims. First, we examine the impact of language variation on the ratings of children's narrative language. Second, we identify participants' ideologies related to narrative language and language variation.

Method

Forty adults listened to and rated six Black second-grade children on the quality of 12 narratives (six fictional, six personal). Adults then completed a quantitative survey and participated in a qualitative interview.

Results

Findings indicated that adults rated students with less variation from mainstream American English (MAE) more highly than students with greater variation from MAE for fictional narratives, but not for personal narratives. Personal narratives tended to be evaluated more favorably by parents than teachers. Black raters tended to assign higher ratings of narrative quality than did White raters. Thematic analysis and conversation analysis of qualitative interviews supported quantitative findings and provided pertinent information about participants' beliefs.

Conclusion

Taken together, quantitative and qualitative results point to a shared language ideology among adult raters of variation from MAE being more acceptable in informal contexts, such as telling a story of personal experience, and less acceptable in more formal contexts, such as narrating a fictional story prompted by a picture sequence.