Integration of Routine Parameters of Glycemic Variability in a Simple Screening Method for Partial Remission in Children with Type 1 Diabetes

Although different criteria were used to define partial remission in type 1 diabetes, the IDAA1C formula has prevailed as it correlates with stimulated C-peptide levels. Our retrospective study evaluated clinical variables associated with the occurrence of IDAA1C-defined partial remission in a series of 239 pediatric patients. Diabetic ketoacidosis and age at diagnosis, but no other clinical feature, influenced the occurrence of remission. We then evaluated whether parameters of glycemic variability used in clinical routine may reliably define partial remission, as these would alleviate confounding factors related to insulin treatment. Using multiple linear regression, we observed that HbA1C levels and percentage of normoglycemia were efficient and sufficient to predict partial remission. These parameters were entered into a formula, called glycemic target-adjusted HbA1C (GTAA1C), that corresponded to HbA1C(%) − (3 × % of normoglycemic values(70–180 mg/dL)). With a threshold of 4.5, this alternative formula predicted partial remission with a sensitivity and a specificity of 72.3% and 92%, respectively, and yielded strong correlation with IDAA1C levels and BETA-2 score, which is a correlate of β-cell function after islet transplantation. We propose GTAA1C, based on routine and objective markers of glycemic variability, as a valid alternative for definition of partial remission in type 1 diabetes

Clinical Study Characteristics and Determinants of Partial Remission in Children with Type 1 Diabetes Using the Insulin-Dose-Adjusted A1C Definition

To evaluate the characteristics and determinants of partial remission (PR) in Belgian children with type 1 diabetes (T1D), we analyzed records of 242 children from our center. Clinical and biological features were collected at diagnosis and during follow-up. PR was defined using the insulin-dose-adjusted A1C definition. PR occurred in 56.2% of patients and lasted 9.2 months (0.5 to 56.6). 25.6% of patients entered T1D with DKA, which correlated with lower PR incidence (17.6% versus 82.3% when no DKA). In our population, lower A1C levels at diagnosis were associated with higher PR incidence and in young children (0-4 years) initial A1C levels negatively correlated with longer PR. Early A1C levels were predictive of PR duration since 34% of patients had long PRs (>1 year) when A1C levels were ≤6% after 3 months whereas incidence of long PR decreased with higher A1Cs. C-peptide levels were higher in patients entering PR and remained higher until 3 years after diagnosis. Initial antibody titers did not influence PR except for anti-IA2 titers that correlated with A1C levels after 2 years. Presence of 2 versus 1 anti-islet antibodies correlated with shorter PR. PR duration did not influence occurrence of severe hypoglycemia or diabetes-related complications but was associated with lower A1C levels after 18 months. We show that, at diagnosis of T1D, parameters associated with -cell mass reserve (A1C, C-peptide, and DKA) correlate with the occurrence of PR, which affects post-PR A1C levels. Further research is needed to determine the long-term significance of PR

Post-Hypoglycemic hyperglycemia are highly relevant markers for stratification of glycemic variability and partial remission status of pediatric patients with new-onset type 1 diabetes.

AimsTo evaluate whether parameters of post-hypoglycemic hyperglycemia (PHH) correlated with glucose homeostasis during the first year after type 1 diabetes onset and helped to distinguish pediatric patients undergoing partial remission or not.MethodsIn the GLUREDIA (GLUcagon Response to hypoglycemia in children and adolescents with new-onset type 1 DIAbetes) study, longitudinal values of clinical parameters, continuous glucose monitoring metrics and residual β-cell secretion from children with new-onset type 1 diabetes were analyzed during the first year after disease onset. PHH parameters were calculated using an in-house algorithm. Correlations between PHH parameters (i.e., PHH frequency, PHH duration, PHH area under the curve [PHHAUC]) and glycemic homeostasis markers were studied using adjusted mixed-effects models.ResultsPHH parameters were strong markers to differentiate remitters from non-remitters with PHH/Hyperglycemia duration ratio being the most sensitive (ratioConclusionPHH parameters are new minimal-invasive markers to discriminate remitters from non-remitters and evaluate glycemic homeostasis during the first year of type 1 diabetes. PHH parameters may also allow patient-targeted therapeutic management of hypoglycemic episodes

Growth response of syndromic versus non-syndromic children born small for gestational age (SGA) to growth hormone therapy: a Belgian study

IntroductionA substantial proportion of SGA patients present with a syndrome underlying their growth restriction. Most SGA cohorts comprise both syndromic and non-syndromic patients impeding delineation of the recombinant human growth hormone (rhGH) response. We present a detailed characterization of a SGA cohort and analyze rhGH response based on adult height (AH).MethodsClinical and auxological data of SGA patients treated with rhGH, who had reached AH, were retrieved from BELGROW, a national database of all rhGH treated patients held by BESPEED (BElgian Society for PEdiatric Endocrinology and Diabetology). SGA patients were categorized in syndromic or non-syndromic patients.Results272 patients were included, 42 classified as syndromic (most frequent diagnosis (n=6): fetal alcohol syndrome and Silver-Russell syndrome). Compared with non-syndromic patients, syndromic were younger [years (median (P10/P90)] 7.43 (4.3/12.37) vs 10.21 (5.43/14.03), p=0.0005), shorter (height SDS -3.39 (-5.6/-2.62) vs -3.07 (-3.74/-2.62), p=0.0253) and thinner (BMI -1.70 (-3.67/0.04) vs -1.14 (-2.47/0.27) SDS, p=0.0054) at start of rhGH treatment. First year rhGH response was comparable (delta height SDS +0.54 (0.24/0.94) vs +0.56 (0.26/0.92), p=0.94). Growth pattern differed with syndromic patients having a higher prepubertal (SDS +1.26 vs +0.83, p=0.0048), but a lower pubertal height gain compared to the non-syndromic group (SDS -0.28 vs 0.44, p=0.0001). Mean rhGH dose was higher in syndromic SGA patients (mg/kg body weight/day 0.047 (0.039/0.064) vs 0.043 (0.035/0.056), p=0.0042). AH SDS was lower in syndromic SGA patients (-2.59 (-4.99/-1.57) vs -2.32 (-3.3/-1.2), p=0.0107). The majority in both groups remained short (<-2 SDS: syndromic 71%, non-syndromic 63%). Total height gain was comparable in both groups (delta height SDS +0.76 (-0.70/1.48) vs +0.86 (-0.12/1.86), p=0.41).ConclusionsCompared to non-syndromic SGA patients, syndromic SGA patients were shorter when starting rhGH therapy, started rhGH therapy earlier, and received a higher dose of rhGH. At AH, syndromic SGA patients were shorter than non-syndromic ones, but their height gain under rhGH therapy was comparable

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

La thérapie cellulaire du diabète : Le point sur les actualités

La possibilité de remplacer des cellules β déficientes par de nouvelles cellules insulino-sécrétantes chez le patient diabétique est démontrée par le succès de la transplantation d’îlots pancréatiques. Le manque de donneurs cadavériques a stimulé la recherche de sources alternatives de cellules β dont le palmarès est dominé par les cellules souches pluripotentes humaines pouvant acquérir des caractéristiques quasiment identiques à celles des cellules β et rétablir l’équilibre glycémique de souris diabétiques. Néanmoins, elles comportent un risque carcinogénique actuellement inévitable. Le pancréas adulte héberge des compartiments cellulaires aux capacités de transdifférenciation établies pouvant être exploitées pharmacologiquement in situ ou via des phases d’expansion en culture. Cette revue s’intéresse aux nouveaux développements concernant la thérapie cellulaire du diabète[Cellular therapy of diabetes: focus on the latest developments]. Islet transplantation has set the ground for diabetes cell therapy and is still undergoing various developments that might improve clinical outcomes. Alternative sources for β-cell replacement strategies are now led by human pluripotent stem cells that demonstrate near-normal β-cell features after in vitro differentiation and which can reverse diabetes in mice. Yet, their propensity for tumor formation is still unresolved. The adult pancreas is suggested as a reservoir of facultative progenitors that could represent adequate candidates for β-cell engineering, either in vivo through pharmacological treatment or after expansion in culture. This review focuses on the latest developments in protocols aiming at de novo production of functional β cells

Hepatocyte differentiation potential of mesenchymal cell lineages for liver regenerative medicine

Human mesenchymal stem cells (MSCs) are being largely studied for their differentiation potential and immunological properties. In the present study, we evaluated the ability to reliably differentiate mesenchymal lineages into hepatocyte-like cells both in vitro and in vivo. For this purpose, we handled several tissue sources and compared typical MSCs from bone marrow (BM) or umbilical cord, to liver-derived mesenchymal-like cells and to fibroblasts. We observed that hepatocyte differentiation of BM-MSCs was incomplete and variable with elective expression of some specific markers. These mesenchymal-derived hepatocyte-like cells (MDHLCs) were also chimerical in their phenotype as they expressed mesenchymal markers while these were down-regulated. We therefore designed differentiation cocktails with an aim to improve MDHLC phenotype and some unexpected results were obtained with LIF cytokine whose action on stem cells for hepatocyte differentiation was not documented. Nevertheless, we observed a limitation in the acquisition yield of hepatic features. Furthermore, the hepatocytelike phenotype of MDHLCs completely disappeared when the cells were incubated into growth medium. However, we showed that hepatic functionality of these cells, as urea secretion and gluconeogenesis, could be increased under specific conditions, suggesting the potential to improve MDHLC phenotype. In vivo, MSCs were able to express hepatic markers into SCID-mice livers while their chimerical phenotype remained. In contrast, MDHLCs down-regulated their hybrid phenotype after transplantation suggesting a beneficial influence of in vitro differentiation step. MSCs were also able to engraft and even partially differentiate into wild-type mice which was a strong argument for their low immunogenicity. Surprisingly, fibroblasts showed highly similar potential than MSCs to differentiate into hepatocyte-like cells both in vitro an in vivo and these results underlined the difficulty to accurately distinguish between both cell types using current techniques. Umbilical cord-derived stem cells (UCMSCs) and adult-derived human liver stem cells (ADHLSCs) were different in nature and displayed a native hybrid phenotype while their differentiation allowed high levels of hepatocyte-like feature acquisition. Together all these data suggest the current possibility to engineer mesenchymal-derived hepatocyte-like cells owning specific features acquisition while remaining limited in their commitment. This highlights the need for further investigations to evidence the usefulness of these mesenchymal lineages for liver cell therapy.(SBIM 3) -- UCL, 200

Hepatocyte differentiation potential of mesenchymal cell lineages for liver regenerative medicine

Human mesenchymal stem cells (MSCs) are being largely studied for their differentiation potential and immunological properties. In the present study, we evaluated the ability to reliably differentiate mesenchymal lineages into hepatocyte-like cells both in vitro and in vivo. For this purpose, we handled several tissue sources and compared typical MSCs from bone marrow (BM) or umbilical cord, to liver-derived mesenchymal-like cells and to fibroblasts. We observed that hepatocyte differentiation of BM-MSCs was incomplete and variable with elective expression of some specific markers. These mesenchymal-derived hepatocyte-like cells (MDHLCs) were also chimerical in their phenotype as they expressed mesenchymal markers while these were down-regulated. We therefore designed differentiation cocktails with an aim to improve MDHLC phenotype and some unexpected results were obtained with LIF cytokine whose action on stem cells for hepatocyte differentiation was not documented. Nevertheless, we observed a limitation in the acquisition yield of hepatic features. Furthermore, the hepatocytelike phenotype of MDHLCs completely disappeared when the cells were incubated into growth medium. However, we showed that hepatic functionality of these cells, as urea secretion and gluconeogenesis, could be increased under specific conditions, suggesting the potential to improve MDHLC phenotype. In vivo, MSCs were able to express hepatic markers into SCID-mice livers while their chimerical phenotype remained. In contrast, MDHLCs down-regulated their hybrid phenotype after transplantation suggesting a beneficial influence of in vitro differentiation step. MSCs were also able to engraft and even partially differentiate into wild-type mice which was a strong argument for their low immunogenicity. Surprisingly, fibroblasts showed highly similar potential than MSCs to differentiate into hepatocyte-like cells both in vitro an in vivo and these results underlined the difficulty to accurately distinguish between both cell types using current techniques. Umbilical cord-derived stem cells (UCMSCs) and adult-derived human liver stem cells (ADHLSCs) were different in nature and displayed a native hybrid phenotype while their differentiation allowed high levels of hepatocyte-like feature acquisition. Together all these data suggest the current possibility to engineer mesenchymal-derived hepatocyte-like cells owning specific features acquisition while remaining limited in their commitment. This highlights the need for further investigations to evidence the usefulness of these mesenchymal lineages for liver cell therapy.(SBIM 3) -- UCL, 200

Characterization of Post-Hypoglycemic Hyperglycemia in Children and Adolescents With Type 1 Diabetes: The EPHICA Study

Background: In patients with diabetes, the dynamics in which hypoglycemia recovers impacts cardiovascular disease risk. Our study investigated the extents of "post-hypoglycemic hyperglycemia (PHH)" (i.e. hypoglycemia that recover to hyperglycemia in any circumstance) and factors likely to influence PHH characteristics in a pediatric cohort of patients with type 1 diabetes (T1D). Methods: We collected retrospective continuous glucose monitoring (CGM) data from 142 pediatric patients with T1D to characterize episodes of PHH during a two-month follow-up period. Factors influencing PHH were determined using univariate and multivariate analyses. Results: In our EPHICA cohort, PHH rate was 0.6 ± 0.3 episode/day and correlated (r=0.33; p<0.0001) with hyperglycemia rate (2.6 ± 0.5 episodes/day). The global proportion of hyperglycemia corresponding to PHH was 0.22 ± 0.1, yet 14.8% of patients had more than 1/3 of hyperglycemia related to PHH. Episodes of PHH lasted 239.6 ± 124.8 minutes with a hyperglycemic peak of 258.8 ± 47.1 mg/dL. Only 12.2% of PHH occurred at night. While a younger age (<12 years) and lower body mass index (BMI) (SDS: -2 to 1.6) were associated with higher daily PHH rates, teenagers (≥12 years) and obese patients experienced longer PHH and higher hyperglycemic peaks. Parameters of glycemic variability (i.e. HbA1C, IDAA1C and GTAA1C) moderately correlated with PHH duration and related hyperglycemic peak. Multivariate analysis confirmed these results, as factors likely to influence PHH rate were phenotype (age and BMI) and glycemic variability parameters (time in range, mean glycemia, HbA1C and GTAA1C). Conclusion: Our EPHICA study highlights the importance of PHH as a prominent component of hyperglycemia in some children and adolescents with T1D. Factors associated with PHH features are age, BMI and parameters of glycemic control. Young and lean children are more prone to experience hypoglycemia that recover with hyperglycemia, but adolescents and obese children tend to experience hyperglycemia of longer duration