Advancing prenatal diagnosis: Echocardiographic detection of Scimitar syndrome in China - A case series.

Objective: To investigate the clinical value of echocardiographic detection in the prenatal early diagnosis of Scimitar syndrome (SS) in fetuses, and to develop better and more accurate management strategies for improved prognosis. Methods: A retrospective analysis was conducted on medical records and fetal echocardiographic findings of all cases diagnosed as SS between April 1, 2016 and June 1, 2021. To summarize its echocardiographic features and distinguishing points, comprehensive clinical data and prognostic information were gathered. Results: Six patients were diagnosed with SS during the study period. Major associated abnormalities included atrial septal defect (n = 3), right inferior pulmonary vein anomalies (n = 2), ventricular septal defect (n = 1), and right aortic arch (n = 1). Post-surgery, all patients exhibited unobstructed pulmonary vein flow and absence of pulmonary hypertension. The average follow-up duration was 24 months, during which five infants underwent surgical intervention for SS. Conclusion: Comprehensive prenatal screening, particularly combined coronal and sagittal views of the fetal thorax, enables accurate diagnosis of right SS. This approach not only aids in timely intervention but also provides crucial prognostic insights for the child's future well-being.

Generation of an induced pluripotent stem cell line (CSBZZUi001-A) from a female Alzheimer's patient carrying the PSEN1 709 T > C heterozygous mutation.

Pluripotent stem cells were generated through the electroporation of episomal plasmids, containing crucial reprogramming factors, into skin fibroblasts extracted from a female Alzheimer's patient harboring the PSEN1 709 T > C (p.Phe237Leu) heterozygous mutation. The pluripotent stem cells exhibit a normal karyotype and express pivotal stem cell markers including TRA-1-60, Nanog, SOX2, and OCT4. Furthermore, their capacity to differentiate into the three germ layers in in vivo teratoma experiments has been substantiated. The pluripotent stem cell line can serve as a cellular model for Alzheimer's disease, offering significant value in elucidating the pathogenesis and therapeutic strategies of the disease.

Distinguishing high-metastasis-potential circulating tumor cells through fluidic shear stress in a bloodstream-like microfluidic circulatory system.

Circulating tumor cells (CTCs) play a critical role as initiators in tumor metastasis, which unlocks an irreversible process of cancer progression. Regarding the fluid environment of intravascular CTCs, a comprehensive understanding of the impact of hemodynamic shear stress on CTCs is of profound significance but remains vague. Here, we report a microfluidic circulatory system that can emulate the CTC microenvironment to research the responses of typical liver cancer cells to varying levels of fluid shear stress (FSS). We observe that HepG2 cells surviving FSS exhibit a marked overexpression of TLR4 and TPPP3, which are shown to be associated with the colony formation, migration, and anti-apoptosis abilities of HepG2. Furthermore, overexpression of these two genes in another liver cancer cell line with normally low TLR4 and TPPP3 expression, SK-Hep-1 cells, by lentivirus-mediated transfection also confirms the critical role of TLR4 and TPPP3 in improving colony formation, migration, and survival capability under a fluid environment. Interestingly, in vivo experiments show SK-Hep-1 cells, overexpressed with these genes, have enhanced metastatic potential to the liver and lungs in mouse models via tail vein injection. Mechanistically, TLR4 and TPPP3 upregulated by FSS may increase FSS-mediated cell survival and metastasis through the p53-Bax signaling pathway. Moreover, elevated levels of these genes correlate with poorer overall survival in liver cancer patients, suggesting that our findings could offer new therapeutic strategies for early cancer diagnosis and targeted treatment development.

Artificial intelligence auxiliary diagnosis and treatment system for breast cancer in developing countries.

BACKGROUND: In many developing countries, a significant number of breast cancer patients are unable to receive timely treatment due to a large population base, high patient numbers, and limited medical resources. OBJECTIVE: This paper proposes a breast cancer assisted diagnosis system based on electronic medical records. The goal of this system is to address the limitations of existing systems, which primarily rely on structured electronic records and may miss crucial information stored in unstructured records. METHODS: The proposed approach is a breast cancer assisted diagnosis system based on electronic medical records. The system utilizes breast cancer enhanced convolutional neural networks with semantic initialization filters (BC-INIT-CNN). It extracts highly relevant tumor markers from unstructured medical records to aid in breast cancer staging diagnosis and effectively utilizes the important information present in unstructured records. RESULTS: The model's performance is assessed using various evaluation metrics. Such as accuracy, ROC curves, and Precision-Recall curves. Comparative analysis demonstrates that the BC-INIT-CNN model outperforms several existing methods in terms of accuracy and computational efficiency. CONCLUSIONS: The proposed breast cancer assisted diagnosis system based on BC-INIT-CNN showcases the potential to address the challenges faced by developing countries in providing timely treatment to breast cancer patients. By leveraging unstructured medical records and extracting relevant tumor markers, the system enables accurate staging diagnosis and enhances the utilization of valuable information.

Physical activity and eating behaviors patterns associated with high blood pressure among Chinese children and adolescents.

BACKGROUND: Physical activity and eating behavior are associated with hypertension in children and adolescents. Revealing the associations between physical activity patterns, eating behavior patterns and high blood pressure (HBP) could help improve the problem of hypertension from the actual children's physical activities and eating behaviors. METHODS: A total of 687 students aged 8-15 years were selected from two nine-year primary and secondary schools using stratified cluster random sampling method. The students' body height, weight, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured, and their physical activity time and eating behaviors were surveyed by using CLASS questionnaire and self-made eating behavior questionnaire, respectively. Exploratory factor analysis (EFA) was used to extract moderate to vigorous physical activity factor (MVPAF), sedentary activity factor (SAF), healthy eating behavior factor (HEBF), unhealthy eating behavior factor (UHEBF). MVPAF ≥ SAF was defined as moderate to vigorous physical activity pattern (MVPAP), MVPAF < SAF was defined as sedentary activity pattern (SAP). HEBF ≥ UHEBF was defined as healthy eating behavior pattern (HEBP), while the opposite was defined as unhealthy eating behavior pattern (UHEBP). Lifestyles includes physical activity patterns and eating behavior patterns. RESULTS: The overall prevalence of hypertension was 5.8% (40/687), and was 5.69% (21/369) in boys and 5.97% (19/318) in girls, respectively. The MVPAF and UHEBF in boys were significantly higher than those in girls (P < 0.01), while the SAF in girls was significantly higher than that in boys (P < 0.05). The SAF was positively correlated with SBP in girls (ß(SE) = 0.14 (0.50), P = 0.016), and was positively correlated with SBP (ß(SE) = 0.21 (1.22), P = 0.000 and DBP (ß(SE) = 0.14 (0.49), P = 0.006) in boys. The MVPAF was negatively correlated with DBP (ß(SE)=-0.11 (0.40), P = 0.022) in boys. In boys, the SAP increased the risks of HBP (OR (95% CI):3.34 (1.30-8.63)) and high DBP (OR (95% CI):3.08 (1.02-9.34)) compared with MVPAP. CONCLUSION: Compared with the boys with MVPAP, boys with SAP may increase the risks of HBP and high DBP. The SAF may be positively associated with SBP in boys and girls, while the MVPAF may be negatively associated with DBP in boys.

3D Biomimetic Models to Reconstitute Tumor Microenvironment In Vitro: Spheroids, Organoids, and Tumor-on-a-Chip.

Decades of efforts in engineering in vitro cancer models have advanced drug discovery and the insight into cancer biology. However, the establishment of preclinical models that enable fully recapitulating the tumor microenvironment remains challenging owing to its intrinsic complexity. Recent progress in engineering techniques has allowed the development of a new generation of in vitro preclinical models that can recreate complex in vivo tumor microenvironments and accurately predict drug responses, including spheroids, organoids, and tumor-on-a-chip. These biomimetic 3D tumor models are of particular interest as they pave the way for better understanding of cancer biology and accelerating the development of new anticancer therapeutics with reducing animal use. Here, the recent advances in developing these in vitro platforms for cancer modeling and preclinical drug screening, focusing on incorporating hydrogels are reviewed to reconstitute physiologically relevant microenvironments. The combination of spheroids/organoids with microfluidic technologies is also highlighted to better mimic in vivo tumors and discuss the challenges and future directions in the clinical translation of such models for drug screening and personalized medicine.

Missense mutation of c.635 T > C in CAPN3 impairs muscle injury repair in a Limb-Girdel Muscular Dystropy Model.

Limb-girdle muscular dystrophy recessive 1 (LGMDR1), previously known as LGMD2A, is a specific LGMD caused by a gene mutation encoding the calcium-dependent neutral cysteine protease calpain-3 (CAPN3). In our study, the compound heterozygosity with two missense variants c.635 T > C (p.Leu212Pro) and c.2120A > G (p.Asp707Gly) was identified in patients with LGMDR1. However, the pathogenicity of c.635 T > C has not been investigated. To evaluate the effects of this novel likely pathogenic variant to the motor system, the mouse model with c.635 T > C variant was prepared by CRISPR/Cas9 gene editing technique. The pathological results revealed that a limited number of inflammatory cells infiltrated the endomyocytes of certain c.635 T > C homozygous mice at 10 months of age. Compared with wild-type mice, motor function was not significantly impaired in Capn3 c. 635 T > C homozygous mice. Western blot and immunofluorescence assays further indicated that the expression levels of the Capn3 protein in muscle tissues of homozygous mice were similar to those of wild-type mice. However, the arrangement and ultrastructural alterations of the mitochondria in the muscular tissues of homozygous mice were confirmed by electron microscopy. Subsequently, muscle regeneration of LGMDR1 was simulated using cardiotoxin (CTX) to induce muscle necrosis and regeneration to trigger the injury modification process. The repair of the homozygous mice was significantly worse than that of the control mice at day 15 and day 21 following treatment, the c.635 T > C variant of Capn3 exhibited a significant effect on muscle regeneration of homozygous mice and induced mitochondrial damage. RNA-sequencing results demonstrated that the expression levels of the mitochondrial-related functional genes were significantly downregulated in the mutant mice. Taken together, the results of the present study strongly suggested that the LGMDR1 mouse model with a novel c.635 T > C variant in the Capn3 gene was significantly dysfunctional in muscle injury repair via impairment of the mitochondrial function.

Hybrid assembly of polymeric nanofiber network for robust and electronically conductive hydrogels.

Electroconductive hydrogels have been applied in implantable bioelectronics, tissue engineering platforms, soft actuators, and other emerging technologies. However, achieving high conductivity and mechanical robustness remains challenging. Here we report an approach to fabricating electroconductive hydrogels based on the hybrid assembly of polymeric nanofiber networks. In these hydrogels, conducting polymers self-organize into highly connected three dimensional nanostructures with an ultralow threshold (~1 wt%) for electrical percolation, assisted by templating effects from aramid nanofibers, to achieve high electronic conductivity and structural robustness without sacrificing porosity or water content. We show that a hydrogel composed of polypyrrole, aramid nanofibers and polyvinyl alcohol achieves conductivity of ~80 S cm-1, mechanical strength of ~9.4 MPa and stretchability of ~36%. We show that patterned conductive nanofiber hydrogels can be used as electrodes and interconnects with favorable electrochemical impedance and charge injection capacity for electrophysiological applications. In addition, we demonstrate that cardiomyocytes cultured on soft and conductive nanofiber hydrogel substrates exhibit spontaneous and synchronous beating, suggesting opportunities for the development of advanced implantable devices and tissue engineering technologies.

Monitoring cell viability in N-nitrosodiethylamine induced acute hepatitis and detection of hydrazine in solution and gas phase with Dual-function fluorescent probes.

The highly toxic N-nitrosodiethylamine (NDEA) and hydrazine (N2H4) caused severe environmental contamination and serious health risks. Herein, we designed the two-photon ratiometric fluorescent probe (Nap-2), emission maximum shifted from 466 nm to 571 nm, to monitor cell viability of NDEA induced acute hepatitis via esterase activity detection. Furthermore, the probe Nap-2 evaluate the hydrazine (N2H4) content in the solution and gas phase. It is worth mentioning that we used NDEA induced acute hepatitis in the mice and evaluated the negative correlation of esterase activity in the tissue cells and serum with Nap-2. The probe Nap-2 exhibited that acute hepatitis induced by NDEA decreased cell viability. Furthermore, we made convenient test papers using Nap-2 to detect N2H4 in solution and gas phase. After adding N2H4, the fluorescence color changed from blue to yellow and was visible to the naked eye. This work provides a convenient tool and method for evaluating the toxicity of NDEA induced acute hepatitis and detecting N2H4 in the environment.

Novel Polarity Fluorescent Probe for Dual-Color Visualization of Lysosomes and Plasma Membrane during Apoptosis.

Apoptosis plays a crucial role in the occurrence of cancer and other diseases. Real-time monitoring of the cell apoptosis process has great significance for cell viability and drug screening. Herein, a novel fluorescent probe was constructed based on the fluorescence resonance energy transfer mechanism, which track the sensitivity of polarity changes, as well as detect the drug-induced cell apoptosis process in a dual-color mode. Importantly, the change of cellular microenvironmental polarity makes it possible to dynamically visualize the process of drug-induced cell apoptosis. More significantly, the designed probe targeted the lysosomes in the living cells to give a blue emission, and it accumulated on the plasma membrane to display red fluorescence during the drug-induced cell apoptosis process. Thus, cell viability could be monitored by both the localization and emission colors of the robust probe. We expect that the unique probe can provide a new blueprint for evaluating and screening apoptosis-related drugs.

Surgical repair of subaortic stenosis resection: 10 years of single-center experience in 65 patients.

BACKGROUND: Subaortic stenosis (SAS) was a rare congenital heart disease of left ventricular outflow tract (LVOT), ranging from "isolated" lesions to "tunnel" or "diffuse" lesions. We conducted a retrospective study to describe the characteristics of patients with different lesions and analyze the risk factors for reoperation. METHODS: In this study, we examined a single-center retrospective cohort of SAS patients undergoing resection from 2010 to 2019. Patients were classified as simple lesion group (n = 37) or complex lesion group (n = 28). Demographics, perioperative findings, and clinical data were analyzed. RESULTS: The surgical effect of the two groups was significantly lower than that before the operation (p < .05). The median age at operation was 6 (3-11.8) years. There was no operative mortality. In complex lesion group, cardiopulmonary bypass time (CPB time), aortic cross-clamping time (ACC time), mechanical ventilation time, and intensive care unit (ICU) stay time were longer. The median follow-up period was 2.8 years (range: 1-3.8), with two late death. Six patients (9.2%) required reoperation due to restenosis or severe aortic insufficiency. The freedom from reoperation rates at 5 years was 66.7% for simple lesion but only 52.3% for complex lesion (p = .036). CONCLUSIONS: Although the lesions include many forms, SAS resection was still satisfactory. However, the reoperation after initial surgical treatment was not infrequent, especially in patients with complex lesion.

Prognostic significance of low expression of B-cell translocation gene 1 (BTG 1) in skin squamous cell carcinoma.

Although the B-cell translocation gene 1 (BTG1) plays an important role in apoptosis and negatively regulates cell proliferation, BTG1 expression in skin squamous cell carcinoma (SCC) has not been reported. In this study, we wanted to investigate the significance of BTG1 expression in SCC and adjacent tissues. The expression of BTG1 protein and mRNA in SCC tissues and adjacent tissues were detected by immunohistochemistry technique (IHC), Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). IHC staining showed that the positive expression rate of BTG1 protein in SCC tissues was 54.00%; and the positive rate was 90.50% in the adjacent tissues. Western blot showed that the expression of BTG1 protein in SCC tissues was significantly lower than that in the adjacent tissues (P less than 0.05). RT-PCR showed that the positive rate of BTG1 mRNA in SCC was 50.50%, which was significantly lower than that in adjacent tissues 89.00% (P less than 0.05). Both BTG1 mRNA and protein expression are related to tumor diameter, stage, tumor metastasis and the degree of tumor differentiation in SCC. Patients exhibiting lower BTG1 protein expression in the SCC tissues had a significantly shorter disease-specific survival rate. BTG1 protein expression, tumor diameter, tumors site and stage were independent factors affecting the overall survival of postoperative patients. Further, BTG1 overexpression inhibited A431 cell proliferation ability, while BTG silencing enhanced A431 cell proliferation ability. The lower expression of BTG1 in SCC may be associated with the occurrence, development and prognosis of SCC.

Feasibility Analysis of Cell-Free DNA Derived from Plasma of Lung Cancer Patients for Next-Generation Sequencing.

Purpose: The quality of specimens directly affects the experimental results. The stability and structural integrity of nucleic acids in samples have a decisive influence on high-throughput sequencing results. Next-generation sequencing (NGS) provides the most comprehensive criteria for evaluating the specimen quality. To test the quality of cell-free DNA (cfDNA) from lung cancer plasma samples stored in our biobank, we conducted a study to evaluate the quality in terms of the genetic level. Methods: A total of 189 peripheral blood samples were collected from patients from patients with EGFR-positive nonsmall cell lung cancer who were seen and treated in Jilin Provincial Cancer Hospital from August 2012 to March 2018. Twelve milliliters of peripheral blood samples were collected and centrifuged at 4°C, 2000 rpm for 15 minutes. Plasma samples were dispensed into cryotubes and stored at -80°C. Plasma cfDNA was extracted by a DNA extraction kit (Qiagen) and the DNA concentration was detected by a Qubit 3.0 fluorometer. Results: The total volume of cfDNA extraction at baseline was 50 µL, the median concentration according to Qubit was 0.633 ng/µL, the range was 0.331-6.09 ng/µL, and the median total DNA was 34.25 ng, ranging from 20.35 to 304.5 ng. The median value of the Qubit concentration in advanced plasma samples was 0.838 ng/µL, ranging from 0.24 to 21.9 ng/µL, and median total DNA was 41.9 ng, ranging from 12.0 to 1095.0 ng. Based on the aforementioned quality assessment factors, 4 of 189 frozen lung cancer baseline plasma samples were not included in further analyses, and for the remaining 185 cases of cfDNA >20 ng, the pass rate was 97.9%. In 143 frozen lung cancer advanced stage plasma samples, 133 cases of cfDNA >20 ng, the pass rate was 93%. Conclusion: Frozen lung cancer plasma samples stored in the biobank for 1-6 years at -80°C under certain conditions still retain a high level of cfDNA, which is suitable for NGS detection.

Simultaneous detection of Cys/Hcy and H2S through distinct fluorescence channels.

Hydrogen sulfide (H2S), cysteine (Cys) and homocysteine (Hcy) play critical roles in human pathologies and there are close interconnections between them in their generation and metabolism in living systems. To elucidate their complex interplay networks, single-molecule fluorescent probes enabling simultaneous detection of H2S and Cys/Hcy from distinct emission channels have been becoming indispensable tools. In this report, we have rationally developed a novel fluorescent probe, NC, for H2S and Cys/Hcy by integrating an amino 7-nitro-1, 2, 3-benzoxadiazole (NBD) moiety and an azide group into the coumarin platform. NC exhibited good selectivity and sensitivity for the discriminatory detection of H2S and Cys/Hcy, and its capability for imaging of intracellular H2S and Cys/Hcy was proved.

Inhibitor structure-guided design and synthesis of near-infrared fluorescent probes for monoamine oxidase A (MAO-A) and its application in living cells and in vivo.

A series of near-infrared fluorescent probes based on inhibitor (clorgyline) structure-guided design were synthesized for the specific detection of MAO-A in cells and in vivo. Moreover, we have successfully used the high specificity of one of the probes to visualize MAO-A activity in zebrafish and tumor tissue for the first time.

Prenatal Diagnosis of Aortopulmonary Window by 2-Dimensional Echocardiography: Summary of 8 Cases.

Aortopulmonary window (APW) is a rare congenital heart anomaly. A total of 8 cases with APW confirmed by echocardiography and surgery were retrospectively reviewed and the echocardiographic features analyzed. Among the 8 APW cases, 5 were type II and 3 were type III, the latter of which includes 2 cases complicated with Berry syndrome. Prenatal echocardiography can provide accurate information for the diagnosis of fetal APW. The prognosis depends on the timing of surgery and the nature of the associated cardiac anomalies.

MiR-340 suppresses the metastasis by targeting EphA3 in cervical cancer.

MicroRNAs (miRNAs) play key roles in cervical cancer metastasis progression. Accumulated evidences have revealed that miRNAs are related to the pathophysiological process. However, the role of miR-340 in cervical cancer and how it works is still not fully interpreted. Using qRT-PCR to examine the expression of miR-340 in cervical cancer tissues. Transwell migration and invasion experiments were used to detect the role of miR-340 in migration and invasion. Luciferase reporter assay, qRT-PCR, and Western blot were used to detect the relationship between miR-340 and EphA3. Using Transwell migration and invasion experiments to investigate the role of EphA3 on migration and invasion. Restoration expriments were also performed. Western blot was used to assay the influence of miR-340 and EphA3 on EMT. We found that miR-340 was downregulated in cervical cancer tissues compared with the normal tissues. Transwell migration and invasion experiments indicated that overexpression of miR-340 frequently inhibited the migration and invasion of cervical cancer cells. EphA3 is a target of miR-340, and ectopic expression of EphA3 can promote the migration and invasion of cervical cancer cells, whereas restoration of EphA3 in miR-340-overexpressing cervical cancer cells reversed the suppressive effects of miR-340. What's more, the process of migration and invasion which regulated by miR-340/EphA3 was depended on adjusting the EMT way. These findings indicate that miR-340 may act as an anti-tumor factor during the process of tumor metastasis through targeting EphA3, suggesting that miR-340 might be a potential new diagnostic and therapeutic molecule for the treatment of cervical cancer.

Simultaneous Detection of Glutathione and Hydrogen Polysulfides from Different Emission Channels.

Glutathione (GSH) and hydrogen polysulfides (H2Sn) play crucial roles in many physiological processes. To unravel the complicated interrelationship and cellular cross-talk between GSH and H2Sn, the development of single-molecule fluorescent probes that can selectively sense GSH and H2Sn simultaneously from different emission channels is highly desirable. In this report, we have developed the first dual-detection fluorescent probe, ACC-SePh, which responded to GSH with green fluorescence emission, whereas it reacted with H2Sn and emitted blue fluorescence. The probe exhibited excellent selectivity and sensitivity toward GSH and H2Sn over other common reactive sulfur species, such as Cys, Hcy and H2S. Importantly, we also demonstrated that ACC-SePh can be used for dual-channel imaging of endogenous GSH and H2Sn in living RAW264.7 cells.

[Application of self made guidance for difficult gastric tube placement in patients with artificial airway].

OBJECTIVE: To use evidence-based nursing on patients with artificial airway to the practice of stomach tube, and to evaluate the self made guidance for difficult gastric tube placement in patients with artificial airway. METHODS: Forty patients with artificial airway and were difficult to put the tube, and admitted to Department of Critical Care Medicine of Harrison International Peace Hospital Affiliated to Hebei Medical University from April to December in 2016 were enrolled as observation group. Through the evidence-based nursing strategy, the related literatures at home and abroad were collected to search clinical evidence and formulate and implement the nursing program, the gastric tube was inserted into the stomach tube under the direct vision of the laryngoscope. Thirty-six patients of difficult gastric tube placement with artificial airway straightly under the direct vision of the laryngoscope from August 2015 to March 2016 were retrospectively analyzed as the control group. The success rate of first catheterization, indwelling time, throat edema and bleeding of pharyngeal mucosa were compared between the two groups. RESULTS: All patients were enrolled in the final analysis. In the control group, 28 patients were successfully placed once, while 8 failed. Only 1 patient in observation group failed to catheterize, and successful placed after symptomatic treatment, the one-time success rate of catheter was significantly higher than that of control group (97.5% vs. 77.8%), and catheter time was significantly shortened (minutes: 4.8±1.2 vs. 5.1±1.0), the difference was statistically significant (both P < 0.05). There were 2 patients with laryngeal edema in the control group and 4 patients of pharyngeal mucosal hemorrhage. In the observation group, there was no laryngeal edema and laryngeal edema occurred in the patients with laryngoscopy, and only 1 patient had a hemorrhage of pharyngeal mucosa. CONCLUSIONS: Using self made guiding device can effectively insert the difficult gastric tube in patients with artificial airway, and increase the one-time success rate of intubation, shorten the catheter time, and have a trend in reduce complication as compared with traditional gastric tube placement.

A method for measurement of free cadmium species in waters using diffusive gradients in thin films technique with an ion-imprinted sorbent.

A diffusive gradients in thin films (DGT) device for the analysis of free Cd(II) species, based on Cd(II) ion-imprinted sorbent (IIS) as the binding agents and commercial polyethersulfone membrane (PES) as diffusion layer, was developed (PES/IIS-DGT). DGT time-series experiments showed that the mass of free Cd(II) species accumulated by PES/IIS-DGT was linear vs. time (R(2) = 0.9953) and the concentration of free Cd(II) species by PES/IIS-DGT was in good agreement with the total dissolved concentrations of free Cd(II) species in simple synthetic solutions where free ionic species dominated. PES/IIS-DGT performance was independent in the range of pH 4.5-7.5 and ionic strength range from 1.0 × 10(-3) to 0.7 mol L(-1). The measurement of free Cd(II) species in synthetic solution containing different concentrations of ligands by PES/IIS-DGT showed an excellent agreement with the value measured by Cd(II) ion selective electrodes (Cd-ISE), indicating that PES/IIS-DGT method is more suitable than Cd-ISE for the measurement of low concentration of free Cd(II) species due to the enrichment of IIS for the analytes.