Citations

Significance Statement Dominantly inherited polycystic kidney and liver phenotypes occur when epithelial cells in these organs have reduction of polycystin-1 functional dosage. In a cohort of genetically unresolved polycystic liver and kidney disease, the authors identified heterozygous loss of function mutations in ALG9 . ALG9 encodes an endoplasmic reticulum enzyme that builds N -glycans, and the authors show that Alg9 inactivation results in impaired polycystin-1 maturation. Using a novel ‘genotype-first’ approach to ascertain individuals based strictly on their ALG9 genotype from a large cohort of exome-sequenced individuals, the authors find that 7/8 (88%) of ALG9 mutation carriers over age 50 have multiple kidney cysts. Together, these findings identify ALG9 as a novel human polycystic kidney and liver disease gene and support the utility of a genotype-driven approach to candidate disease gene validation and genotype-phenotype correlation. Background Mutations in PKD1 or PKD2 cause typical autosomal dominant polycystic kidney disease (ADPKD), the most common monogenic kidney disease. Dominantly inherited polycystic kidney and liver diseases on the ADPKD spectrum are also caused by mutations in at least six other genes required for protein biogenesis in the endoplasmic reticulum, the loss of which results in defective production of the PKD1 gene product, the membrane protein polycystin-1 (PC1). Methods We used whole-exome sequencing in a cohort of 122 patients with genetically unresolved clinical diagnosis of ADPKD or polycystic liver disease to identify a candidate gene, ALG9 , and in vitro cell-based assays of PC1 protein maturation to functionally validate it. For further validation, we identified carriers of ALG9 loss-of-function mutations and noncarrier matched controls in a large exome-sequenced population-based cohort and evaluated the occurrence of polycystic phenotypes in both groups. Results Two patients in the clinically defined cohort had rare loss-of-function variants in ALG9 , which encodes a protein required for addition of specific mannose molecules to the assembling N-glycan precursors in the endoplasmic reticulum lumen. In vitro assays showed that inactivation of Alg9 results in impaired maturation and defective glycosylation of PC1. Seven of the eight (88%) cases selected from the population-based cohort based on ALG9 mutation carrier state who had abdominal imaging after age 50; seven (88%) had at least four kidney cysts, compared with none in matched controls without ALG9 mutations. Conclusions ALG9 is a novel disease gene in the genetically heterogeneous ADPKD spectrum. This study supports the utility of phenotype characterization in genetically-defined cohorts to validate novel disease genes, and provide much-needed genotype-phenotype correlations.

Abstract Background: IDH mutated gliomas are critically dependent on glutaminase for glutamate biosynthesis. CB-839 is a novel glutaminase-1 inhibitor which has demonstrated efficacy in both genetically engineered and patient derived IDH mutated glioma cells, especially in combination with radiation. These preclinical studies evaluate the pharmacodynamic and pharmacokinetic impact of combining CB-839 with TMZ in patient derived xenograft (PDX) glioma models. Methods: GBM164 is a PDX model derived from an IDH1 mutant, 1p/19q non-codeleted glioma. D- and L-2HG levels in untreated GBM164 tumors were compared to GBM6 tumors (IDH wildtype glioma PDX) by GC/MS. Athymic nude mice bearing GBM164 flank tumors were treated with CB-839 (200 mg/kg PO BID x 9 doses) and/or temozolomide (50 mg/kg PO daily x 5 doses) and sacrificed four hours after the last dose to harvest plasma, normal brain and flank tumor. Tumor metabolomics were assessed by GC/MS. DNA damage signaling in tumors was assessed by Western blotting for KAP1 / Chk1 / Chk2 phosphorylation and H2AX / Rad51. Tumor, plasma and brain pharmacokinetics were assessed by LC/MS/MS. Results: Total 2HG levels in GBM164 were 18-fold higher than GBM6. CB-839 monotherapy reduced tumor glutamate (18% reduction, p = 0.15) and aspartate (30% reduction, p = 0.06) when compared to vehicle, however these changes did not reach statistical significance. The combination of CB-839 and TMZ more significantly reduced both tumor glutamate (30% reduction, p = 0.03) and aspartate (34% reduction, p < 0.001) when compared to TMZ monotherapy. CB-839 did not significantly increase DNA damage compared to vehicle, and the combination of CB-839 and TMZ did not significantly increase DNA damage compared to TMZ monotherapy. The mean tumor: plasma ratios of CB-839 concentrations were 0.68 and 0.58 in mice treated with CB-839 monotherapy and CB-839/TMZ, respectively. The mean brain: plasma ratios of CB-839 concentrations were 0.07 and 0.12 in mice treated with CB-839 monotherapy and CB-839/TMZ, respectively. Conclusion: The addition of CB-839 to TMZ significantly reduces glioma aspartate and glutamate in an IDH1 mutant PDX glioma model, without any impact on DNA damage. Survival studies are in progress to assess the efficacy of CB-839 when used in combination with RT and/or TMZ. Citation Format: Sani Haider Kizilbash, Danielle M. Burgenske, Samuel McBrayer, Sandhya Devarajan, Shiv K. Gupta, Taro Hitosugi, Lihong He, Mark A. Schroeder, Brett L. Carlson, Marina Gelman, Charles A. Kunos, Joel M. Reid, Alex A. Adjei, Jann N. Sarkaria. The addition of CB-839 to temozolomide significantly reduces glioma aspartate and glutamate in an IDH mutated patient derived glioma xenograft model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3870.

Precis: This study is the first to report micropulse transscleral cyclophotocoagulation (MP-TSCPC) use in only good vision patients. MP-TSCPC significantly reduced intraocular pressure (IOP) and glaucoma medication use without any significant reduction in visual acuity at every postoperative follow-up point. Purpose: To evaluate outcomes of MP-TSCPC in eyes with baseline best-corrected visual acuity (BCVA) of ≥20/60. Methods: A retrospective review of patients who underwent MP-TSCPC at Mayo Clinic and Ross Eye Institute from July 2016 to August 2017 with BCVA of ≥20/60, and a minimum of 3 months follow-up. Results: A total of 61 eyes of 46 patients (68.80±17.12 y) underwent MP-TSCPC with a mean follow-up of 10.2±3.1 months. Mean IOP and mean number of glaucoma medications used were significantly reduced from baseline at every follow-up time point ( P <0.0001). At month 12, mean IOP was reduced 40.2% from baseline with 85.4% of the patients having an IOP reduction of ≥20%, and mean glaucoma medication use reduced by 0.82±0.53 with 79.6% of the patients having a reduction of ≥1 medication. There was no significant reduction in BCVA from baseline at any follow-up point ( P >0.05), except for 10 eyes with a vision loss of ≥2 lines and 5 out of 10 eyes had cataract progression. The probability of complete success (IOP range, 6 to 21 mm Hg or ≥20% IOP reduction; BCVA loss ≤2 lines, no reoperation for glaucoma) was 74.14%, 83.61%, 84.21%, and 75.0% at months 1, 3, 6, 12, respectively. The probability of qualified success (above criteria for IOP, no reoperation and BCVA loss >2 lines) was 81.03%, 91.80%, 94.74%, and 93.75% at months 1, 3, 6, 12, respectively. Conclusions: MP-TSCPC should be considered earlier in the management of glaucoma and can possibly be offered as an alternative to incisional glaucoma surgeries.

ABSTRACT Here, we show that cells expressing the adherens junction protein nectin-1 capture nectin-4-containing membranes from the surface of adjacent cells in a trans-endocytosis process. We find that internalized nectin-1–nectin-4 complexes follow the endocytic pathway. The nectin-1 cytoplasmic tail controls transfer: its deletion prevents trans-endocytosis, while its exchange with the nectin-4 tail reverses transfer direction. Nectin-1-expressing cells acquire dye-labeled cytoplasmic proteins synchronously with nectin-4, a process most active during cell adhesion. Some cytoplasmic cargo remains functional after transfer, as demonstrated with encapsidated genomes of measles virus (MeV). This virus uses nectin-4, but not nectin-1, as a receptor. Epithelial cells expressing nectin-4, but not those expressing another MeV receptor in its place, can transfer infection to nectin-1-expressing primary neurons. Thus, this newly discovered process can move cytoplasmic cargo, including infectious material, from epithelial cells to neurons. We name the process nectin-elicited cytoplasm transfer (NECT). NECT-related trans-endocytosis processes may be exploited by pathogens to extend tropism. This article has an associated First Person interview with the first author of the paper.

BACKGROUND: In January 2016, as part of the Maintenance of Certification in Anesthesiology (MOCA) program, the American Board of Anesthesiology launched MOCA Minute, a web-based longitudinal assessment, to supplant the former cognitive examination. We investigated the association between participation and performance in MOCA Minute and disciplinary actions against medical licenses of anesthesiologists. METHODS: All anesthesiologists with time-limited certificates (ie, certified in 2000 or after) who were required to register for MOCA Minute in 2016 were followed up through December 31, 2016. The incidence of postcertification prejudicial license actions was compared between those who did and did not register and compared between registrants who did and did not meet the MOCA Minute performance standard. RESULTS: The cumulative incidence of license actions was 1.2% (245/20,006) in anesthesiologists required to register for MOCA Minute. Nonregistration was associated with a higher incidence of license actions (hazard ratio, 2.93 [95% confidence interval {CI}, 2.15–4.00]). For the 18,534 (92.6%) who registered, later registration (after June 30, 2016) was associated with a higher incidence of license actions. In 2016, 16,308 (88.0%) anesthesiologists met the MOCA Minute performance standard. Of those not meeting the standard (n = 2226), most (n = 2093, 94.0%) failed because they did not complete the required 120 questions. Not meeting the standard was associated with a higher incidence of license actions (hazard ratio, 1.92 [95% CI, 1.36–2.72]). CONCLUSIONS: Both timely participation and meeting performance standard in MOCA Minute are associated with a lower likelihood of being disciplined by a state medical board.

The American Board of Anesthesiology (ABA) has been administering an oral examination as part of its initial certification process since 1939. Among the 24 member boards of the American Board of Medical Specialties, 13 other boards also require passing an oral examination for physicians to become certified in their specialties. However, the methods used to develop, administer, and score these examinations have not been published. The purpose of this report is to describe the history and evolution of the anesthesiology Standardized Oral Examination, its current examination development and administration, the psychometric model and scoring, physician examiner training and auditing, and validity evidence. The many-facet Rasch model is the analytic method used to convert examiner ratings into scaled scores for candidates and takes into account how difficult grader examiners are and the difficulty of the examination tasks. Validity evidence of the oral examination includes that it measures aspects of clinical performance not accounted for by written certifying examinations, and that passing the oral examination is associated with a decreased risk of subsequent license actions against the anesthesiologist. Explaining the details of the Standardized Oral Examination provides transparency about this component of initial certification in anesthesiology.