[Establishment and validation of a predictive model for neurogenic urinary tract injury in children].

Objective: To establish a predictive model for upper urinary tract damage in children with neurogenic bladder and verify its efficacy. Methods: From January 2011 to December 2021, 143 children with NB in the Children's Hospital of Chongqing Medical University and 84 children with NB in the First Affiliated Hospital of Zhengzhou University were selected as the research objects. The former is set as the training set and the latter is set as the validation set, and the general parameters of the two are compared. The independent risk factors of upper urinary tract damage in children with NB were screened out by Lasso regression, and multivariate logistic regression analysis and a nomogram prediction model was established. The models were validated internally and externally on the training set and validation set, respectively, and the area under the receiver operating curve (ROC) was used to verify the accuracy of the model. Results: A total of 227 children with NB were included in this study, including 121 males and 106 females, aged (10.2±3.8) years. There was no significant difference in other parameters except age between the training set and validation set (all P>0.05); Lasso regression and multivariate logistic regression analysis showed that detrusor leakage point pressure (DLPP) ≥ 40 cmH2O (OR=4.76, 95%CI: 2.01-11.26, 1 cmH2O=0.098 kPa), overactive bladder (OAB) (OR=3.08, 95%CI: 1.34-7.04), bladder compliance (BC)<20 ml/cm H2O (OR=3.65, 95%CI: 1.41-9.47), history of previous urinary tract infection (OR=2.73, 95%CI: 1.09-6.81), and abdominal pressure/other voiding patterns (OR=2.86, 95%CI: 1.20-6.82) were risk factors for upper urinary tract damage in children with NB (all P<0.05). The above parameters were used to establish a nomogram model of upper urinary tract damage in children with NB. The internal and external validation results show that the AUC values for the training and validation sets were 0.84 (95%CI: 0.77-0.91) and 0.86 (95%CI: 0.79-0.94), respectively. Conclusion: The prediction model of upper urinary tract damage in children with NB constructed in this study has high discrimination, accuracy and clinical applicability, which can help clinicians identify high-risk patients and make individualized treatment design for these patients.

Preparation of dendrimer-like polyamidoamine immobilized silica gel and its application to online preconcentration and separation palladium prior to FAAS determination.

A amino-terminated G 4.0 dendrimer-like polyamidoamine (PAMAM) immobilized silica gel (PAMAMSG) was prepared with a divergent method by repeating two processes: (1) Michael addition of methyl acrylate (MA) to surface amino groups; and (2) amidation of the resulting esters with ethylenediamine (EDA) from gamma-aiminopropyl silica gel (APSG) core. It was then used for the first time as microcolumn packing for the flame atomic absorption spectrometry (FAAS) determination of trace or ultra trace Pd(II), after flow injection (FI) online preconcentration and separation process. A limit of detection (LOD) of 3.9ngml(-1) was achieved when 0.200mugml(-1) Pd(II) was preconcentrated in 0.2moll(-1) HCl medium with a sampling flow rate of 6.0mlmin(-1) for 60s and the relative standard deviation (R.S.D.) was 1.7%. The proposed method was successfully used for the determination of Pd in two metallurgical samples.

Capillary electrophoresis system with flow injection sample introduction and chemiluminescence detection on a chip platform.

A capillary electrophoresis (CE) system with chemiluminescence (CL) detection was combined with flow injection (FI) sample introduction on a chip platform. A falling-drop interface was applied to perform FI split-flow sample introduction while achieving electrical isolation from the CE high voltage. A tubular reservoir at the capillary outlet served as both the CL reaction and detection cell for the luminol-peroxide-metallic ion chemiluminescent reaction, with the luminol included in the separation buffer and CL reagent H2O2 continuously introduced into the outlet reservoir. An optical fiber was positioned within the outlet reservoir directly opposite, and 300 microns away from, the capillary outlet for collecting and transferring the generated CL to the PMT. The peak height signals and the separation efficiency were almost independent of the reagent flow-rate, making the system a robust one. The performance of the system was illustrated by the separation of Co(II) and Cu(II), achieving baseline separation in 60 s. Detection limits (3 sigma) were 1.25 x 10(-8) and 2.3 x 10(-6) mol dm-3 for Co(II) and Cu(II), respectively. Peak height precision was 1.9% RSD (n = 9) at the 10(-7) mol dm-3 Co level.

Synthesis of rhodanine-bonded silica gel and its application in the preconcentration and separation of noble metals.

A silica gel based sorbent containing rhodanine as functional group (RDSG) was prepared. Its adsorption and separation characteristics for Ag(I), Au(III) and Pd(II) were studied by flow-injection (FI) on-line preconcentration. Influence of different experimental parameters such as acidity, eluent, co-existing ions were investigated. Trace amounts of Ag, Au and Pd could be efficiently adsorbed by rhodanine-bonded silica gel from acidic solution and eluted with thiourea solution. Common co-existing ions exhibited virtually no interference to the preconcentration and determination. The adsorption capacity of RDSG was 0.0352, 0.107 and 0.122 mmol/g for Ag, Au and Pd, respectively. Detection limits of 0.004, 0.022 and 0.019 microg/mL for Ag, Au and Pd, respectively, were achieved with a sampling time of 60 s at a flow rate of 5.0 mL/min. The relative standard deviation were 0.5%, 0.9% and 1.7% for 0.040 microg/mL Ag, 0.200 microg/mL Au and 0.300 microg/mL Pd. The sorption property did not change after 1,000 cycles of sorption-desorption. The contents of Ag and Au in three national certified ore samples and Pd in a secondary nickel alloy, an anode slime and a CoCl2 electrolytic solution were determined. The results showed good agreement with the certified values.

Application of a macroporous resin containing imidazoline groups to preconcentration and separation of gold, platinum and palladium prior to ICP-AES determination.

A new functional resin with a long functional side chain was synthesized by modification of aminated macroporous poly(vinyl chloride) resin with cyanoethylene and ethylenediamine. Traces of Au(III), Pt(IV) and Pd(II) in aqueous solution were quantitatively adsorbed in the acidity range of pH 4 and C(H(+)) 3 M. The rate of equilibration is high; Cu(2+), Fe(3+), Ni(2+), etc. exhibit little interference on the adsorption of the sought noble metals. The saturated adsorption capacities for Au(III), Pt(IV), Pd(II) and Ir(IV) in 2 M HCl were 4.0, 1.57, 2.26, 1.85 mmol g(-1). Adsorbed ions can be quantitatively desorbed by 4% thiourea +0.25 M H(2)SO(4). The resin has good reusability, and can be used for preconcentration and separation of Au(III), Pt(IV) and Pd(II) prior to their determination by ICP-AES with satisfactory results.