Citations

Skeletal muscle mitochondrial protein synthesis is regulated in part by insulin. The development of insulin resistance with diet-induced obesity may therefore contribute to impairments to protein synthesis and decreased mitochondrial respiration. Yet the impact of diet-induced obesity and insulin resistance on mitochondrial energetics is controversial, with reports varying from decreases to increases in mitochondrial respiration. We investigated the impact of changes in insulin sensitivity on long-term rates of mitochondrial protein synthesis as a mechanism for changes to mitochondrial respiration in skeletal muscle. Insulin resistance was induced in C57BL/6J mice using 4 wk of a high-fat compared with a low-fat diet. For 8 additional weeks, diets were enriched with pioglitazone to restore insulin sensitivity compared with nonenriched control low-fat or high-fat diets. Skeletal muscle mitochondrial protein synthesis was measured using deuterium oxide labeling during weeks 10–12. High-resolution respirometry was performed using palmitoyl-l-carnitine, glutamate+malate, and glutamate+malate+succinate as substrates for mitochondria isolated from quadriceps. Mitochondrial protein synthesis and palmitoyl- l-carnitine oxidation were increased in mice consuming a high-fat diet, regardless of differences in insulin sensitivity with pioglitazone treatment. There was no effect of diet or pioglitazone treatment on ADP-stimulated respiration or H2O2 emission using glutamate+malate or glutamate+malate+succinate. The results demonstrate no impairments to mitochondrial protein synthesis or respiration following induction of insulin resistance. Instead, mitochondrial protein synthesis was increased with a high-fat diet and may contribute to remodeling of the mitochondria to increase lipid oxidation capacity. Mitochondrial adaptations with a high-fat diet appear driven by nutrient availability, not intrinsic defects that contribute to insulin resistance.

Purpose: Several studies have demonstrated that patients have a poor understanding of prognosis, survival, and effectiveness of chemotherapy, particularly in the setting of advanced cancer. This study examines oncology patients’ understanding of their illness based on accurate reporting of stage at diagnosis and knowledge of cancer status (ie, free of cancer or in remission v active disease). Materials and Methods: Two hundred eight patients with cancer previously treated at our large community-based cancer institute participated in the Consumer-Based Cancer Care Value Index field survey. Electronic medical record documentation of stage at diagnosis and cancer status was compared with patients’ self-reported responses. Concordance of responses and variables influencing discordance were evaluated. Results: In 51.0% of patients, self-reported cancer stage matched the abstracted stage, with the highest concordance in patients with advanced cancer (72%) versus patients with stage I to III disease (36.4% to 61.5%). Unexpectedly, discordance was lower among patients with advanced cancer compared with patients with stage I to III cancer ( P = .0528). Patients who were concordant for cancer stage at diagnosis were significantly more likely to be female ( P = .001), be younger than age 65 years ( P = .01), have an income > $60,000 ( P = .03), and have more education ( P = .02). In 64.4% of patients, self-reported cancer status (ie, free of cancer or in remission v active disease) matched the abstracted status. Nearly 30% of patients were not sure about their status, even when they were free of cancer or in remission. Conclusion: Our findings confirm that more than one quarter of patients with advanced cancer have poor illness understanding and highlight that an even greater number of patients with early stage I to III cancer have poor illness understanding. These observations highlight the need to improve illness understanding for patients across the entire cancer continuum.

Policy Points: The policy context of direct‐to‐consumer personal genomic testing (DTC‐PGT) has been evolving over the last decade, with little empirical data available about consumers’ perspectives. A majority of consumers of DTC‐PGT supported expanded access to services and their integration into the medical context and opposed more governmental regulation. Consumers’ attitudes about access to services and regulation did not vary based on the specific genetic risk information they received from companies, but may vary based on whether consumers perceived their DTC experience negatively. ContextWhile policymakers have been considering the appropriateness of direct‐to‐consumer personal genomic testing (DTC‐PGT) for more than a decade, there is little empirical data on consumers’ views regarding the regulation of these products. No research has assessed whether consumers’ personal experience with testing is related to their views about access to and regulation of DTC tests.MethodsData were analyzed from the PGen Study, a longitudinal prospective cohort of DTC‐PGT customers of 23andMe (n = 564) and Pathway Genomics (n = 377; total N = 941). Consumers were sent an electronic survey before receiving genetic test results and again 6 months after receipt of results.FindingsAt the 6‐month follow‐up, more than 80% of participants believed that people have a right to access genetic information directly, that parents should be able to get DTC‐PGT testing for their children, and that genetic information should be kept private. Participants supported health insurance coverage of PGT (60%), wider availability of PGT (68%), and inclusion of genetic information in medical records (63%). Participants were less supportive of government regulation (28%) and restricting testing to clinical settings (14%). Conservative political ideology was associated with less support for government regulation (P < 0.001), as was feeling more confident in one's genetic knowledge (P < 0.05). Participants’ level of computed genetic risk for common diseases, as indicated by their actual test results received from companies, showed no relationship with attitudes. However, those who perceived that they had received elevated risk results expressed lower support for expanded availability and incorporation of PGT into health care (P < 0.01). Those who reported being upset by their genetic test results were less likely to endorse access to DTC products without a medical professional (P < 0.01).ConclusionsPGT consumers supported expanded access to these services and opposed additional regulation. Users who had a negative personal experience with PGT testing were less supportive of expanded availability without a medical professional.

The absence of a positive family history (PFH) in 10%–25% of patients poses a diagnostic challenge for autosomal dominant polycystic kidney disease (ADPKD). In the Toronto Genetic Epidemiology Study of Polycystic Kidney Disease, 210 affected probands underwent renal function testing, abdominal imaging, and comprehensive PKD1 and PKD2 mutation screening. From this cohort, we reviewed all patients with and without an apparent family history, examined their parental medical records, and performed renal imaging in all available parents of unknown disease status. Subsequent reclassification of 209 analyzed patients revealed 72.2% (151 of 209) with a PFH, 15.3% (32 of 209) with de novo disease, 10.5% (22 of 209) with an indeterminate family history, and 1.9% (four of 209) with PFH in retrospect. Among the patients with de novo cases, we found two families with germline mosaicism and one family with somatic mosaicism. Additionally, analysis of renal imaging revealed that 16.3% (34 of 209) of patients displayed atypical PKD, most of which followed one of three patterns: asymmetric or focal PKD with PFH and an identified PKD1 or PKD2 mutation (15 of 34), asymmetric and de novo PKD with proven or suspected somatic mosaicism (seven of 34), or focal PKD without any identifiable PKD1 or PKD2 mutation (eight of 34). In conclusion, PKD without an apparent family history may be due to de novo disease, missing parental medical records, germline or somatic mosaicism, or mild disease from hypomorphic PKD1 and PKD2 mutations. Furthermore, mutations of a newly identified gene for ADPKD, GANAB , and somatic mosaicism need to be considered in the mutation-negative patients with focal disease.