Challenges in achieving adequate glycemic control among children with type 1 diabetes mellitus in a resource-limited setting: A cross-sectional study from Sudan.

OBJECTIVE: To assess glycemic control and associated factors in children with type 1 diabetes mellitus (T1DM) attending the pediatric diabetes clinic in Wad-Madani City, Sudan. METHODS: This cross-sectional observational study was conducted at a referral center in Sudan. The study population consisted of children aged 1-18 years who had been diagnosed with T1DM for more than 1 year and were under regular follow-up in the clinic. Data on their glycemic control and sociodemographic and clinical characteristics were captured. RESULTS: Out of 211 enrolled patients, 120 (56.9 %) were females. The mean age was 11.7 years (SD = 4.0), with the mean age at diagnosis of 6.7 years (SD = 4.0). Only 6.2 % achieved adequate glycemic control. Adolescents had particularly poor control (97.8 %). The mean glycosylated hemoglobin (HBA1c) level was 10.4 % (90 mmol/mol). Inferior glycemic control was associated with advancing age, older age at diagnosis, belonging to single-parent households, less frequent self-monitoring of blood glucose (SMBG), and having a greater number of siblings or household members. A third of patients (33.8 %) had had one or more diabetes ketoacidosis (DKA) episodes in the previous year. There was a high prevalence of lipodystrophy (34.1 %) and arthropathy (25.1 %). CONCLUSIONS: An exceptionally low proportion of children with T1DM achieved adequate glycemic control, with adolescents particularly struggling. SMBG frequency and family dynamics emerged as potential factors, highlighting the urgent need for tailored interventions and improved diabetes education in resource-limited settings.

Effects of alternate wetting and drying on oxyanion-forming and cationic trace elements in rice paddy soils: impacts on arsenic, cadmium, and micronutrients in rice.

Rice is a global dietary staple and its traditional cultivation under flooded soil conditions leads to accumulation of arsenic (As) in rice grains. Alternate wetting and drying (AWD) is a widely advocated water management practice to achieve lower As concentrations in rice, water savings, and decreased methane emissions. It is not yet clear whether AWD leads to tradeoffs between concentrations of As and micronutrient elements (e.g., zinc, manganese, molybdenum) in rice grain. We analyzed pore water chemistry and rice grain composition data from a field experiment conducted in Arkansas, USA, in 2017 and 2018 to test the hypothesis that AWD will have diverging effects on oxyanion-forming (arsenic, molybdenum) vs. cationic (cadmium, zinc, manganese, copper) trace elements. This was hypothesized to occur via decreases in soil pH and/or precipitation of iron oxide minerals during oxidizing conditions under AWD. Solubility of all trace elements, except zinc, increased in more reducing conditions. Consistent with our hypothesis, AWD tended to increase grain concentrations of cationic elements while decreasing grain concentrations of oxyanionic elements. Decreases in total As in rice grains under AWD were mainly driven by changes in dimethylarsinic concentrations, with negligible changes in inorganic As. Linear mixed-effects modeling showed that effects of AWD on grain composition were more significant in 2017 compared to 2018. These differences may be related to the timing of dry-downs in the developmental stage of rice plants, with dry-downs during the heading stage of rice development leading to larger impacts on grain composition of certain elements. We also observed significant interannual variability in grain elemental composition from continuously-flooded fields and postulate the warmer temperatures in 2018 may have played a role in these differences.

Effects of organic sulfur and arsenite/dissolved organic matter ratios on arsenite complexation with dissolved organic matter.

The speciation and fate of arsenic (As) in soil-water systems is a topic of great interest, in part due to growing awareness of As uptake into rice as an important human exposure pathway to As. Rice paddy and other wetland soils are rich in dissolved organic matter (DOM), leading to As/DOM ratios that are typically lower than those in groundwater aquifers or that have been used in many laboratory studies of As-DOM interactions. In this contribution, we evaluate arsenite (As(III)) binding to seven different DOM samples at As/DOM ratios relevant for wetland pore waters, and explore the chemical properties of the DOM samples associated with high levels of As(III)-DOM complexation. We integrate data from wet chemical analysis of DOM chemical properties, dialysis equilibrium experiments, and two-site ligand binding models to show that in some DOM samples, 15-60% of As(III) can be bound to DOM at environmentally-relevant As/DOM ratios of 0.0032-0.016 µmol As/mmol C. Binding decreases as the As(III)/DOM ratio increases. The organic sulfur (Sorg) content of the DOM samples was strongly correlated with levels of As(III)-DOM complexation and "strong" binding site densities, consistent with theories that thiols are strong binding ligands for As(III) in natural organic matter. Finally, a whole-cell E. coli biosensor assay was used to show that DOM samples most effective at complexing As(III) also led to decreased microbial As(III) uptake at low As/DOC ratios. This work demonstrates that naturally-occurring variations in the Sorg content of DOM has a significant impact on As(III) binding to DOM, and has implications for As(III) availability to microorganisms.