Predicting chronic kidney disease progression with artificial intelligence.

BACKGROUND: The use of tools that allow estimation of the probability of progression of chronic kidney disease (CKD) to advanced stages has not yet achieved significant practical importance in clinical setting. This study aimed to develop and validate a machine learning-based model for predicting the need for renal replacement therapy (RRT) and disease progression for patients with stage 3-5 CKD. METHODS: This was a retrospective, closed cohort, observational study. Patients with CKD affiliated with a private insurer with five-year follow-up data were selected. Demographic, clinical, and laboratory variables were included, and the models were developed based on machine learning methods. The outcomes were CKD progression, a significant decrease in the estimated glomerular filtration rate (eGFR), and the need for RRT. RESULTS: Three prediction models were developed-Model 1 (risk at 4.5 years, n = 1446) with a F1 of 0.82, 0.53, and 0.55 for RRT, stage progression, and reduction in the eGFR, respectively,- Model 2 (time- to-event, n = 2143) with a C-index of 0.89, 0.67, and 0.67 for RRT, stage progression, reduction in the eGFR, respectively, and Model 3 (reduced Model 2) with C-index = 0.68, 0.68 and 0.88, for RRT, stage progression, reduction in the eGFR, respectively. CONCLUSION: The time-to-event model performed well in predicting the three outcomes of CKD progression at five years. This model can be useful for predicting the onset and time of occurrence of the outcomes of interest in the population with established CKD.

First Report of the Cereal Cyst Nematode Heterodera filipjevi on Wheat in Serbia.

The most globally recognized and economically important nematode on wheat is the cereal cyst nematode (CCN) complex (1). One of the most important species of this group is Heterodera filipjevi (Madzidov, 1981) Mulvey and Golden, 1983. During regular soil quarantine control in September 2010, Heterodera sp. cysts were found in soil samples originating from a wheat field in Gunaros, Vojvodina Province, in northern Serbia. The wheat was a winter crop grown in a dryland production system and had an average cyst density of 2.50/100 cm3 of soil. Morphologically, the cysts were golden brown and lemon shaped with a posterior protuberance. The vulval cone was bifenestrate with horseshoe-shaped semifenestra, bullae, and underbridge. Cyst measurements (n = 30) ranged as follows: cyst length (without neck): 511.50 to 899.00 µm, cyst width: 201.50 to 682.00 µm, fenestral length: 44.80 to 65.60 µm, fenestral width: 24.00 to 40.00 µm, vulval bridge length: 12.80 to 20.80 µm, vulval bridge width: 6.40 to 14.40 µm, vulval slit: 6.00 to 12.80 µm, and underbridge length: 60.00 to 112.00 µm. The second-stage juveniles had an offset head, stylet with characteristic anchor-shaped basal knobs, four incisures, and a conical tail with a rounded tip. The J2 morphometrics (n = 30) were: length: 447.30 to 611.10 µm, width: 22.40 to 25.60 µm, stylet: 20.80 to 24.00 µm, tail length: 56.00 to 68.80 µm, tail width: 14.40 to 19.20 µm, and hyaline length: 35.20 to 44.80 µm. The ITS region was used for molecular analysis. Each DNA sample was extracted from a single cyst. Sequencing was done with primers TW81 and AB28 (2). In comparison with other H. filipjevi populations, the obtained sequence (GenBank Accession No. JX235959) revealed 99 to 100% similarity. Morphological and molecular data confirmed the existence of H. filipjevi. This is, to our knowledge, the first report of H. filipjevi from Serbia. Since wheat has important socioeconomic value for Serbia, after extensive surveys, additional phytosanitary measures may be necessary to prevent the spread of this parasite. References: (1) J. M. Nicol et al. Current Nematode Threats to World Agriculture. Genomics and Molecular Genetics of Plant-Nematode Interactions, Springer, New York, 2011. (2) A. M. Skantar et al. J. Nematol. 39:133, 2007.

Determination of lithium in wines by ion chromatography.

Lithium ion can be added as a denaturing agent to wines unsuitable for consumption. Accuracy of flame atomic emission spectroscopy with direct nebulization, which is commonly adopted for discovering illegal use of denatured wines, was found to be compromised by Na+, K+, NH4+, Mg2+, Ca2+ and ethanol contained in wine. Ion chromatography (IC) was tested in order to propose an alternative method for legal controls. Experimental design was used to investigate the influence on the accuracy of the determination of Li+ at ppb levels, of Na+ and ethanol content of wine and of fluctuations of eluent flow-rate and composition. It turned out that IC quantification of Li+ can be affected by eluent parameters rather than by wine composition. Since the former can be maintained under the operators control, while the latter cannot, IC was judged preferable to AES for legal controls of Li+ in wines.