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OBJECTIVE Continuous glucose monitoring (CGM) improves diabetes management, but its reliability in individuals on hemodialysis is poorly understood and potentially affected by interstitial and intravascular volume variations. RESEARCH DESIGN AND METHODS We assessed the accuracy of a factory-calibrated CGM by using venous blood glucose measurements (vBGM) during hemodialysis sessions and self-monitoring blood glucose (SMBG) at home. RESULTS Twenty participants completed the protocol. The mean absolute relative difference of the CGM was 13.8% and 14.4%, when calculated on SMBG (n = 684) and on vBGM (n = 624), and 98.7% and 100% of values in the Parkes error grid A/B zones, respectively. Throughout 181 days of CGM monitoring, the median time in range (70–180 mg/dL) was 38.5% (interquartile range 29.3–57.9), with 28.7% (7.8–40.6) of the time >250 mg/dL. CONCLUSIONS The overall performance of a factory-calibrated CGM appears reasonably accurate and clinically relevant for use in practice by individuals on hemodialysis and health professionals to improve diabetes management.

OBJECTIVE Meals are a major hurdle to glycemic control in type 1 diabetes (T1D). Our objective was to test a fully automated closed-loop control (CLC) system in the absence of announcement of carbohydrate ingestion among adolescents with T1D, who are known to commonly omit meal announcement. RESEARCH DESIGN AND METHODS Eighteen adolescents with T1D (age 15.6 ± 1.7 years; HbA1c 7.4 ± 1.5%; 9 females/9 males) participated in a randomized crossover clinical trial comparing our legacy hybrid CLC system (Unified Safety System Virginia [USS]-Virginia) with a novel fully automated CLC system (RocketAP) during two 46-h supervised admissions (each with one announced and one unannounced dinner), following 2 weeks of data collection. Primary outcome was the percentage time-in-range 70–180 mg/dL (TIR) following the unannounced meal, with secondary outcomes related to additional continuous glucose monitoring-based metrics. RESULTS Both TIR and time-in-tight-range 70–140 mg/dL (TTR) were significantly higher using RocketAP than using USS-Virginia during the 6 h following the unannounced meal (83% [interquartile range 64–93] vs. 53% [40–71]; P = 0.004 and 49% [41–59] vs. 27% [22–36]; P = 0.002, respectively), primarily driven by reduced time-above-range (TAR >180 mg/dL: 17% [1.3–34] vs. 47% [28–60]), with no increase in time-below-range (TBR CONCLUSIONS A new fully automated CLC system with automatic prandial dosing was proven to be safe and feasible and outperformed our legacy USS-Virginia in an adolescent population with and without meal announcement.

Objective: Physical activity is a major challenge to glycemic control for people with type 1 diabetes. Moderate-intensity exercise often leads to steep decreases in blood glucose and hypoglycemia that closed-loop control systems have so far failed to protect against, despite improving glycemic control overall. Research Design and Methods: Fifteen adults with type 1 diabetes (42 ± 13.5 years old; hemoglobin A(1c) 6.6% ± 1.0%; 10F/5M) participated in a randomized crossover clinical trial comparing two hybrid closed-loop (HCL) systems, a state-of-the-art hybrid model predictive controller and a modified system designed to anticipate and detect unannounced exercise (APEX), during two 32-h supervised admissions with 45 min of planned moderate activity, following 4 weeks of data collection. Primary outcome was the number of hypoglycemic episodes during exercise. Continuous glucose monitor (CGM)-based metrics and hypoglycemia are also reported across the entire admissions. Results: The APEX system reduced hypoglycemic episodes overall (9 vs. 33; P = 0.02), during exercise (5 vs. 13; P = 0.04), and in the 4 h following (2 vs. 11; P = 0.02). Overall CGM median percent time 180 mg/dL (18.5% vs. 16.6%, P = 0.15). Overnight control was notable for both systems with no hypoglycemia, median percent in time 70–180 mg/dL at 100% and median percent time 70–140 mg/dL at ∼96% for both. Conclusions: A new closed-loop system capable of anticipating and detecting exercise was proven to be safe and feasible and outperformed a state-of-the-art HCL, reducing participants' exposure to hypoglycemia during and after moderate-intensity physical activity. ClinicalTrials.gov NCT03859401.

Identifying naturally occurring peptides bound to HLA class I molecules recognized by HLA-restricted cytotoxic T lymphocytes (CTL) is both relevant and central to the development of effective immunotherapeutic strategies against cancer. Several cancer-related genes have been reported for ovarian cancer, but very few are known to be naturally processed T cell epitopes. In the present study we used mass spectrometry to identify 16 novel HLA-A2-bound peptides from HLA-A2(+) ovarian cancer cell lines. All 16 peptides are derived from source proteins with diverse functions and marked homology to known proteins found in public databases. Synthetic peptide analogues of identified sequences were found to stabilize HLA-A2.1, albeit with varying affinities. The peptides were found to be antigenic in that a primary CD8(+) CTL response could be elicited from normal donor blood. The CTL generated were not only peptide specific, but failed to recognize targets pulsed with control peptides. In addition, recognition of shared HLA-A2-restricted epitopes by these CTL is suggested by their reactivity with a subset of HLA-A2(+) tumor lines and freshly isolated cancer cells or cell lines established from peritoneal ascites. These results were further corroborated by competitive inhibition of lysis of an otherwise susceptible cell line in the presence of cold peptide-pulsed targets. Furthermore, lack of recognition of several HLA-A2(+) control cell lines or cells isolated from normal ovaries suggests that these peptides are cancer related. These findings broaden the list of CTL-defined antigens that could lead to the development of multi-epitope vaccines for the treatment of ovarian cancer.

Identification ofMycobacterium tuberculosisproteins that can provide immunological protection against tuberculosis is essential for the development of a more effective vaccine. To identify new vaccine targets, we have used immunoaffinity chromatography to isolate class I HLA-A*0201-peptide complexes fromM. tuberculosis-infected cells and sequenced the isolated peptides by mass spectrometry. From this material, we have identified three peptides derived from a singleM. tuberculosisprotein that is encoded by theM. tuberculosisRv0341 gene. Although no known protein encoded by the Rv0341 gene has been described, it is predicted to give rise to a 479-amino-acid protein with a molecular mass of 43.9 kDa. The three peptides identified are all nested and were found to be antigenic, in that they were capable of inducing peptide-specific, CD8+T cells from healthy blood donors in vitro and capable of recognizing and lysingM. tuberculosis-infected dendritic cells. This methodology provides a powerful tool for the identification ofM. tuberculosisproteins that can be evaluated as potential vaccine candidates.

The urinary iodine is the best laboratory measure of iodine nutrition. Several simple methods are suitable for developing countries. The present article reviews these briefly. It also presents preliminary information on "Fast B", a rapid method that puts samples into convenient ranges rather than giving absolute values for individuals. This grouping by ranges is satisfactory for many epidemiological purposes and is considerably more rapid than other approaches. The choice among methods depends on the intended application, the number of samples, the cost and the technical capability. Having several different methods available allows the user to select the one best suited to specific needs. Further development of simple methods and appropriate combinations of steps from different ones deserve encouragement as a means of improving monitoring in the campaign to achieve sustainable elimination of iodine deficiency.

The thyroid couples two iodotyrosine molecules to produce thyroid hormone at the acceptor site in thyroglobulin, leaving dehydroalanine or pyruvate at the donor position. Previous work has located the acceptors but not the principal iodotyrosine donors. We incorporated [14C]tyrosine into beef thyroid slices, isolated and iodinated the [14C]thyroglobulin (Tg I), separated its N-terminal approximately 22-kDa hormone-rich peptide, and digested the latter with trypsin and endoproteinase Glu-C (EC 3.4.21.19). Nonlabeled thyroglobulin (Tg II) was isolated from the same glands and processed similarly, without iodination in vitro. Tg I was used to initially recognize pyruvate in peptide fractions, and Tg II was used to then identify its location in the thyroglobulin polypeptide chain. Sequencing of a tryptic peptide by mass spectrometry and Edman degradation showed a cleavage after Val129. An endoproteinase Glu-C-generated peptide had the predicted molecular mass of a fragment containing residues 130-146 with Tyr130 replaced by pyruvate; the identification of this peptide was supported by obtaining the expected shortened fragment after tryptic digestion. 14C-labeled pyruvate was identified in the same fraction as this peptide. We conclude that Tyr130 is an important donor of the outer iodothyronine ring. Its likely acceptor is Tyr5, the most important hormonogenic site of thyroglobulin, because Tyr5 and Tyr130 are proximate, because they are the most prominent early iodination sites in this part of thyroglobulin, and because the N-terminal region was previously found capable of forming T4 by itself.

Thyroid hormones are synthesized within the thyroglobulin (Tg) molecule and must be released to reach the circulation and exert their metabolic effect. We have previously shown that three lysosomal endopeptidases, cathepsin B, D, and L, are active in the early stages of intrathyroidal degradation of Tg but do not themselves release free hormone. The current study examines the role of exopeptidases as the next step in thyroid hormone release. Human thyroidal cathepsin B and two partially purified exopeptidases, dipeptidyl peptidase II (DP-PII) and lysosomal dipeptidase I (LDPI), were used to digest the 20-kDa N-terminal peptide of rabbit Tg, which contains the dominant T4 site of Tg at residue 5. Cathepsin B acted as an endopeptidase initially, producing small T4-containing peptides. After more extended digestion, it also acted as an exopeptidase, producing the dipeptide T4-Gln, corresponding to residues 5 and 6 of Tg. Lysosomal dipeptidase I alone had no effect on 20 kDa but acted in combination with cathepsin B to release T4 from the T4-Gln dipeptide. Although addition of DPPII increased the release of hormone from 125I-Tg by an extract of DPPII-deficient lysosomes, it had no apparent effect on the degradation of the 20-kDa peptide, either alone or in combination with cathepsin B or LDPI. Thus DPPII may act in synergy with some other endopeptidase, or alternatively, may play a role in the release of hormone from other sites in Tg. We conclude that the N-terminus of Tg, which contains its major hormonogenic site, is particularly susceptible to hydrolysis by the endopeptidase cathepsin B and that cathepsin B additionally has an important exopeptidase action that allows it to release a T4 dipeptide that is then further degraded by LDPI to release free T4.

We studied thyroid tissue from two siblings with Pendred's syndrome (familial goiter and congenital deafness), both with the Mondini-type inner ear malformation, goiter, and hypothyroidism. Iodine trapping and peroxidase levels were grossly normal. Thyroglobulin (Tg), the only iodoprotein found, had a normal monomer size (330 kilodaltons), but low content of hormone and iodine. Tg's expected N-terminal peptides of 26 and 18 kilodaltons, usually formed in association with iodination and thyroid hormone synthesis, were absent, but appeared after iodination in vitro. Reverse transcription of ribonucleic acid from Pendred thyroid tissue and amplification by polymerase chain reaction of specific regions encoding the most important hormonogenic sites of Tg revealed a normal complementary DNA sequence corresponding to the first 100 amino acid residues in Tg's N-terminus. However, 3 of 35 clones of the 3'-region corresponding to the Tg C-terminus exhibited a deletion of nucleotides 7860-7994; this deletion was not present in any of the 150 clones from 7 other thyroids we examined. Four Pendred clones had a 2-nucleotide deletion at positions 7870-7871, a change that would result in a premature stop codon and was found in thyroids from several other subjects as well. We conclude that the messenger ribonucleic acid encoding the 3'-region of Tg can be abnormal in Pendred's syndrome. Some, but not all, of these changes also occur in other human thyroids. Further work is necessary to show if and how these alterations relate to defective hormone synthesis and goiter.