Walnut consumption and gut microbial metabolism: Results of an exploratory analysis from a randomized, crossover, controlled-feeding study.

BACKGROUND & AIMS: The effect of walnut-related modulation of gut microbiota composition on microbiota functionality is unknown. The aim was to characterize the effect of a walnut-enriched diet (WD), compared to a fatty acid-matched diet devoid of walnuts (WFMD) and a diet where oleic acid replaces alpha-linolenic acid (ORAD), on bacterial gene expression. METHODS: A 3-period, randomized, crossover, controlled-feeding study was conducted. Participants were provided a 2-week run-in standard western diet (SWD; 50% kcal carbohydrate, 16% protein, 34% fat, 12% SFA). Following the SWD in random sequence order, participants were provided the WD, WFMD, and ORAD (48% carbohydrate; 17% protein; fat 35%; 7% SFA). The WD contained 18% of energy from walnuts (57 g/d/2100 kcal). The WFMD and ORAD were devoid of walnuts; liquid non-tropical plant oils were included in these diets. Metatranscriptomic analyses were performed as an exploratory outcome. RESULTS: The analytical sample included 35 participants (40% female) with a mean ± SD age of 43 ± 10 y and BMI of 30.3 ± 4.9 kg/m2. The ⍺-diversity of taxa actively expressing genes, assessed by observed species (p = 0.27) and Pielou's Evenness (p = 0.09), did not differ among the diets. The ⍺-diversity of actively expressed genes was greater following the WD compared to the WFMD and ORAD as assessed by the observed genes and Pielou's Evenness metrics (p < 0.05). ß-Diversity of the actively expressed genes differed following the WD compared to the WFMD (p = 0.001) and ORAD (p = 0.001); ß-diversity did not differ between the WFMD and ORAD. Active composition analyses showed increased Gordonibacter (p < 0.001) activity following the WD vs. the ORAD. Greater expression of many genes was observed following the WD compared to the WFMD and ORAD. Following the WD, greater expression of metabolism-related genes encoding glycine amidinotransferase (GATM; K00613) and arginine deiminase (K01478) was observed compared to the WFMD. Greater expression of glycine amidinotransferase (GATM; K00613) by Gordonibacter was also observed following the WD vs. the WFMD and ORAD. CONCLUSION: Our results suggest walnut intake may increase endogenous production of homoarginine through gut microbiota-mediated upregulation of GATM, which is a novel mechanism by which walnuts may lower cardiovascular disease risk. However, given the exploratory nature replication is needed. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT02210767).

Motivation to Impact: Medical Student Volunteerism in the COVID 19 Pandemic.

Objective: Volunteerism represents an important mechanism to promote resilience, empathy, and general well-being in medical students, a group that stands to benefit. Medical students report feelings of fatigue, burnout, exhaustion, and stress that correlates with poor academic performance, and significant decline in empathy over the 3rd year of both MD and DO programs. Volunteer motivations have been shown to mediate participant well-being. The relationship between medical student volunteer motivations and specific outcomes during the COVID-19 pandemic has not been addressed. Methods: We characterized features of medical student volunteers during the COVID-19 pandemic in 2020, including volunteering motivation using the Volunteer Functions Inventory, the types of activities in which they participated, and the physical, psychosocial, and emotional outcomes they experienced following volunteering. Results: Altruistic and humanitarian values-centric motivation predicts positive volunteering outcomes including increased resilience, ability to deal with disappointment and loss, and ability to cope with the COVID-19 pandemic. Values-centric motivation also increases volunteer empathy independent of educational stage. Values-centric participants were more likely to select volunteering activities with patient contact, which promotes student empathy and resilience. Conversely, career-centric motivation does not predict positive outcomes. These students are more likely to engage in research-oriented activities. Conclusions: The efficacy of integrating volunteerism into medical school curricula may be limited by professional pressure that manifests as career-oriented motivation. We propose that practical integration should promote altruistic and humanitarian values-centric participant orientation to the volunteering process, which is associated with enhanced recruitment, preservation of empathy, and additional positive volunteering outcomes of interest.

Race-insurance disparities in prostate patients' magnetic resonance imaging biopsies and their subsequent cancer care: a New York State cohort study.

For organ-confined prostate cancer, socioeconomic factors influencing Magnetic Resonance Imaging (MRI)-guided biopsy utilization and downstream prostate cancer patients' care are unknown. This retrospective, observational cohort study used the New York Statewide Planning and Research Cooperative System (SPARCS) billing-code driven database to examine the impact of prostate patients' socioeconomic characteristics on prostate cancer care defined as initial biopsy, 2-month post-biopsy cancer diagnoses, and within 1-year cancer-related intervention, controlling for other risk factors. From 2011-2017, the population studied (n = 18,253) included all New York State-based, male, residents aged 18 to 75 without a prior prostatectomy receiving a first-time biopsy; 760 such patient records in 2016 were removed due to data quality concerns. Major exposures included patient age, race, ethnicity and insurance. The major outcome included receipt of MRI biopsy versus standard biopsy and for these sub-populations, subsequent 2-month post-biopsy metastatic versus non-metastatic prostate cancer diagnosis and within 1-year prostate cancer treatment (prostatectomy with or without radiation versus prostatectomy-only) were compared using dichotomous (primary) and time-to-event (secondary) endpoints. Of 17,493 patients with a first-time prostate biopsy, 3.89% had MRI guided biopsies; of the 17,128 patients with no pre-biopsy cancer diagnosis, the subsequent prostate cancer diagnosis rate was 42.59%. For 6,754 non-metastatic prostate cancer patients with 1-year follow-up, 1,674 (24.79%) received surgery (with or without radiation) and 495 (7.33%) received radiation-only. Holding other factors constant, multivariable regression models identified that race-insurance was a primary predictor of MRI-guided biopsy use. Compared to commercially insured White patients, Black patients across all insurance categories received MRI-guided biopsies less frequently; Commercially insured and self-pay Black patients also had increased chance of prostate cancer diagnosis. Across all insurers, Black patients had lower likelihood of prostatectomies. In contrast, Black and White patients with government insurance were more likely to have within 1-year radiation-only treatments versus commercially insured White patients. Thus, across the prostate cancer care continuum, race-insurance affected prostate cancer-related service utilization. Future research should evaluate the generalizability of these New York State findings.