Six weeks of caloric restriction lowers fasting glucose and EGP with accompanying improvements in β cell function in people with type 2 diabetes. An additional 6 wk of caloric restriction maintained the improvement in glucose metabolism. This trial was registered at clinicaltrials.gov as NCT01094054.

Background and Purpose: Clopidogrel is an antiplatelet drug that is metabolized to its active form by the CYP2C19 enzyme. The CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) found a significant interaction between loss-of-function allele status for the CYP2C19 gene and the effect of dual antiplatelet therapy with aspirin and clopidogrel on the rate of early recurrent stroke following acute transient ischemic attack/minor stroke. The POINT (Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke Trial), similar in design to CHANCE but performed largely in North America and Europe, demonstrated a reduction in early recurrent stroke with dual antiplatelet therapy compared with aspirin alone. This substudy was done to evaluate a potential interaction between loss-of-function CYP2C19 alleles and outcome by treatment group in POINT. Methods: Of the 269 sites in 10 countries that enrolled patients in POINT, 134 sites participated in this substudy. DNA samples were genotyped for CYP2C19 *2, *3, and *17 alleles and classified as being carriers or noncarriers of loss-of-function alleles. Major ischemia consisted of ischemic stroke, myocardial infarction, or ischemic vascular death. Results: Nine hundred thirty-two patients provided analyzable DNA. The rates of major ischemia were 6.7% for the aspirin group versus 2.3% for the dual antiplatelet therapy group (hazard ratio, 0.33 [95% CI, 0.09–1.21]; P =0.09) among carriers of loss-of-function allele. The rates of major ischemia were 5.6% for the aspirin group versus 3.7% for the dual antiplatelet therapy group (hazard ratio, 0.65 [95% CI, 0.32–1.34]; P =0.25) among noncarriers. There was no significant interaction by genotype for major ischemia ( P =0.36) or stroke ( P =0.33). Conclusions: This substudy of POINT found no significant interaction with CYP2C19 loss-of-function carrier status and outcome by treatment group. Failure to confirm the findings from the CHANCE trial may be because the loss-of-function alleles tested are not clinically important in this context or because the 2 trials had differences in racial/ethnic composition. Additionally, differences between the 2 trials might be due to chance as our statistical power was limited to 50%. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00991029.

Exendin-(9,39) is a competitive antagonist of glucagon-like peptide-1 (GLP-1) at its receptor. However, it is unclear if it has direct and unique effects of its own. We tested the hypothesis that exendin-(9,39) and GLP-1-(9,36)amide have direct effects on hormone secretion and β-cell function as well as glucose metabolism in healthy subjects. Glucose containing [3-3H]glucose was infused to mimic the systemic appearance of glucose after a meal. Saline, GLP-1-(9,36)amide, or exendin-(9,39) at 30 pmol/kg/min (Ex 30) or 300 pmol/kg/min (Ex 300) were infused in random order on separate days. Integrated glucose concentrations were slightly but significantly increased by exendin-(9,39) (365 ± 43 vs. 383 ± 35 vs. 492 ± 49 vs. 337 ± 50 mmol per 6 h, saline, Ex 30, Ex 300, and GLP-1-[9,36]amide, respectively; P = 0.05). Insulin secretion did not differ among groups. However, insulin action was lowered by exendin-(9,39) (25 ± 4 vs. 20 ± 4 vs. 18 ± 3 vs. 21 ± 4 10−4 dL/kg[min per μU/mL]; P = 0.02), resulting in a lower disposition index (DI) during exendin-(9,39) infusion (1,118 ± 118 vs. 816 ± 83 vs. 725 ± 127 vs. 955 ± 166 10−14 dL/kg/min2 per pmol/L; P = 0.003). Endogenous glucose production and glucose disappearance did not differ significantly among groups. We conclude that exendin-(9,39), but not GLP-1-(9,36)amide, decreases insulin action and DI in healthy humans.

Pathogenic hemizygous variants in the SH2D1A gene cause X-linked lymphoproliferative (XLP) syndrome, a rare primary immunodeficiency usually associated with fatal Epstein-Barr virus infection. Disease onset is typically in early childhood, and the average life expectancy of affected males is $11 years. We describe clinical, radiographic, neuropathologic, and genetic features of a 49year-old man presenting with central nervous system vasculitis that was reminiscent of adult primary angiitis but which was unresponsive to treatment. The patient had 2 brothers; 1 died of aplastic anemia at age 13 and another died of diffuse large B-cell lymphoma in his sixties. Exome sequencing of the patient and his older brother identified a novel hemizygous variant in SH2D1A (c.35G>T, p.Ser12Ile), which encodes the signaling lymphocyte activation molecule (SLAM)-associated protein (SAP). Molecular modeling and functional analysis showed that this variant had decreased protein stability, similar to other pathogenic missense variants in SH2D1A. The family described in this report highlights the broadly heterogeneous clinical presentations of XLP and the accompanying diagnos-tic challenges in individuals presenting in adulthood. In addition, this report raises the possibility of a biphasic distribution of XLP cases, some of which may be mistaken for age-related malignancies and autoimmune conditions.

Moyamoya disease (MMD) is a chronic, occlusive cerebrovascular disease that predominantly affects East Asian populations. The major genetic mutation associated with MMD in Asian populations is the p.R4810K substitution in Ring Finger Protein 213 (RNF213). Interestingly, variants in the RNF213 gene have also been implicated in intracranial aneurysms (IA) in French-Canadian population, suggesting that variation in this gene may play a broader role in cerebrovascular phenotypes. In a recent genome-wide association study (GWAS) in a Caucasian population, variants rs6565653 and rs12601526 in the Solute Carrier Family 26 Member 11 (SLC26A11) gene, which is less than 10kb away from RNF213, showed a suggestive association with young onset ischemic stroke. We propose that the signal could be tagging an association with common variation in the RNF213 gene. We analyzed the linkage disequilibrium (LD) pattern in the SLC26A11-RNF213 gene region and we observed a high LD between variants in this region based on D’ values. We show that SLC26A11 rs6565653 variant tags RNF213 rs12944088, a missense variant that is more common among subjects with IA than in healthy individuals. Given the fact that rs6565653 tags several RNF213 variants, it is highly likely that some of these tagged variants modify the risk of suffering stroke. The LD analyses suggest that the SLC26A11 signal from the young onset ischemic stroke GWAS performed in a Caucasian population is also tagging variation at the RNF213 loci, supporting the hypothesis that RNF213 variation may result in a variety of neurovascular disorders including an increased risk and/or worse prognosis following ischemic stroke in Caucasian population.

Opsoclonus myoclonus syndrome (OMS) is a rare immune-mediated paraneoplastic or para/-post-infectious syndrome characterized by “dancing” eye movements, myoclonus, and ataxia. Neuropsychiatric symptoms have also been reported. Without treatment, OMS may progress to further neurological impairment and even death. Autoimmune attack of CNS structures in OMS is most commonly mediated by anti-Ri (also known as ANNA2) IgG antibodies, with additional findings implicating antibodies targeting various neurotransmitter receptors. Prompt immunotherapy and neoplasm treatment may result in improvement. We report a novel association of Contactin-Associated Protein-Like 2 (Caspr2) antibodies occurring in association with paraneoplastic OMS. While breast cancer and small cell lung cancer (SCLC) are more commonly associated with OMS among adults, we characterize a novel association between Caspr2 antibody in a patient with mixed non-small cell and small cell lung carcinoma.

Introduction: Across 269 international sites, the POINT trial randomly assigned 4881 patients with minor ischemic stroke or high-risk transient ischemic attack to receive either clopidogrel at a loading dose of 600 mg on day 1 followed by 75 mg per day, plus aspirin at a dose of 50-325 mg per day or the same range of doses of aspirin alone. Dual antiplatelet therapy significantly reduced the incidence of major ischemic events, but also significantly increased the incidence of major hemorrhage. Clopidogrel is a prodrug that requires metabolism by the cytochrome P450 complex to act on the P2Y12 platelet receptor. CYP2C19 (cytochrome P450 family 2 subfamily C polypeptide 19) variants are associated with variable rates of metabolism of clopidogrel and thus pharmacogenomic effects may be clinically relevant. Methods: Genomic DNA was extracted from peripheral blood monocytes using the standard protocols. Genotyping for CYP2C19 *2, *3 and *17 alleles (rs4244285, rs4986893 and rs12248560) defines metabolizer/activator status and was performed using custom TaqMan Allelic Discrimination Assays on a QuantStudio™ 7 Flex Real-Time PCR System. Results: As of June 28, 2018, a total of 445 trial participants had DNA available for analysis. CYP2C19 allele genotyping demonstrated approximately one quarter of subjects (n=127; 28.6%) would be defined as poor or Intermediate metabolizers of clopidogrel. Conclusions: Based on targeted cytochrome P 450 genotyping, about one quarter of POINT patients have reduced clopidogrel activation. Additional genotyping is ongoing. We plan to present results assessing whether the treatment effect of clopidogrel is limited to those with CYP2C19 genotypes associated with normal drug metabolism.

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