Nomogram to predict haemorrhagic transformation after stroke thrombolysis: a combined brain imaging and clinical study.

AIM: To construct a novel nomogram by integrating computed tomography perfusion (CTP) and clinical parameters for individualised prediction of haemorrhagic transformation (HT) in intravenous thrombolysis (IVT)-treated acute ischaemic stroke (AIS) patients. METHODS: Anterior circulation AIS patients who underwent IVT at a single centre from January 2018 to June 2020 were reviewed retrospectively. The CTP parameters of two regions of interest (ROI), the entire perfusion lesion areas, and the infract core areas, were assessed. HT was documented by follow-up CT 24 ± 2 h after IVT. Multivariable logistic regression was conducted by including clinical variables and CTP parameters to identify the independent predictors of HT. A nomogram was developed based on the independent predictors. The discriminative value and calibration of the nomogram were tested by concordance indexes (C-indexes) and calibration plots. Internal validation was performed using fivefold cross-validation. RESULTS: The nomogram was generated using the complete data from 341 patients. Seven variables were included in the final nomogram, including: the relative cerebral blood volume (rCBV), permeability surface (PS), and relative PS (rPS) in infract core areas, the relative time to maximum (rTmax) and rPS in entire perfusion lesion areas, the National Institutes of Health Stroke Scale (NIHSS), and atrial fibrillation (AF). The C-indexes were 0.815 and 0.817 for the nomogram and internal validation. The calibration plots showed excellent agreement. CONCLUSION: This is the first study establishing a nomogram based on CTP and clinical parameters to predict HT after stroke thrombolysis.

[The application of intravoxel incoherent motion diffusion imaging and 3D arterial spin labeling perfusion imaging in the evaluation of acute cerebral infarction].

Objective: To investigate the clinical value of magnetic resonance (MR) intravoxel incoherent motion (IVIM) diffusion imaging and 3D pseudo continuous arterial spin labeling (3D-pcASL) perfusion imaging in the evaluation of acute cerebral infarction. Methods: MR images of 49 patients with unilateral acute cerebral infarction diagnosed and treated in Affiliated Yancheng Hospital of Southeast University Medical College from October 2015 to February 2019 were retrospectively analyzed. High signal infarction area (S(D)) on diffusion image slice with the biggest lesion level and abnormal perfusion area (S(CBF)) on the corresponding level were measured. The presence of ischemic penumbra (IP) was represented by S(CBF)> S(D), and patients were divided into group IP and group non-IP. Regions of interest were set on the infarction core, brain tissue near the edge of the lesion (BNL) and their corresponding contralateral regions. The values of apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion related diffusion coefficient (D(*)), perfusion fraction (f) and cerebral blood flow (CBF) of each region of interest were recorded and relative values of infarction lesion to its contralateral region (rADC, rD, rD(*), rf, rCBF) were calculated. Differences of each parameter value between infarction core, BNL and their corresponding contralateral regions and of each relative parameter value between infarction core and BNL, and between the two groups were compared.The differential diagnostic efficacy of relative parameter value with differences between groups was analyzed by receiver operating characteristics (ROC) curve. The correlations of each relative parameter value of 3D-pcASL and IVIM sequences were analyzed. Results: The ADC, D, f and CBF values of infarction core were significantly lower than those of contralateral regions in both groups (all P<0.01). Among all parameters of BNL in both groups, only the CBF value of group IP was significantly lower than that of contralateral region ((27.58±3.53) vs (41.20±5.66) ml·100 g(-1)·min(-1), P<0.01). The rADC, rD, rf and rCBF of infarction core were significantly lower than those of BNL in both groups (all P<0.01). The rCBF of BNL in group IP was significantly lower than that in group non-IP (0.68±0.12 vs 0.97±0.15, P<0.01), and the area under the curve was 0.949, the optimal threshold was 0.823, and the youden index was 0.855 for identifying the two groups. Other relative parameters values of infarction core and BNL had no statistical difference between the two groups. There were positive correlations between rCBF and rADC, rD, rf (r=0.428,0.335,0.565) of infarction core, rADC and rD, rf (r=0.853,0.602) of infarction core, also rADC and rD (r=0.336) of BNL (all P<0.05). Conclusions: IVIM can effectively evaluate the difusion and perfusion information of acute cerebral infarction lesions. However, its perfusion related parameters are not as good as 3D-pcASL in IP evaluation, which should be flexibly selected according to the actual needs of patients' condition evaluation.

[The combined application of magnetic resonance DTI and 3D-pcASL in differential diagnosis of hyper-acute and acute ischemic cerebral infarction].

Objective: To explore the clinical value of magnetic resonance diffusion tensor imaging (DTI) combined with 3D pseudo continuous arterial spin labeling (3D-pcASL) perfusion imaging in differential diagnosis of hyper-acute and acute ischemic cerebral infarction. Methods: A total of 42 patients with confirmed unilateral ischemic cerebral infarction from February 2015 to October 2017 of Affiliated Yancheng Hospital of Southeast University Medical College were collected. DTI and 3D-pcASL images of hyper-acute (14 patients, group A) and acute (28 patients, group B) ischemic cerebral infarction were retrospectively analyzed. The slice with the biggest lesion on diffusion weighted imaging (DWI) was selected to measure the infarction area (S(DWI)) and abnormal cerebral blood flow (CBF) perfusion area (S(CBF)). Regions of interest (ROIs) were set on the infarction core (IC) area, mismatch area of S(CBF) and S(DWI) (MACD), and their corresponding contralateral regions. The values of CBF, average diffusion coefficient (DC(avg)), and fractional anisotropy (FA) parameter images in these ROIs in patients with both S(CBF)>S(DWI) and lower perfusion in the IC were recorded. The relative values of each infarction lesion to its corresponding contralateral region (rCBF, rFA, and rDC(avg)) were calculated. Differences of each parameter value between the IC, MACD and their corresponding contralateral regions and of the relative values between group A and group B were investigated. Results: The CBF and DC(avg) values in the IC and the CBF value in the MACD were lower than that of their corresponding contralateral regions in both groups (P<0.05). The DC(avg) in the MACD in group A patients and the FA in the IC in group B patients were lower than that in their corresponding contralateral regions (P<0.05). Compared to group A patients, group B patients showed decreased rFA, rDC(avg) in the IC and rFA in the MACD, and increased rDC(avg) and rCBF in the MACD (P<0.05). Receiver operating characteristics (ROC) curve analysis indicated that the best diagnosis cut off values of the rFA and rDC(avg) values in the IC and the rCBF, rFA, and rDC(avg) values in the MACD were 0.890 and 0.541 and 1.139, 0.902 and 0.455, respectively, for identifying two groups. Conclusion: The changes of the CBF, FA, and DC(avg) values and their relative values can be applied to differentially diagnose patients with hyper-acute and acute cerebral infarction, which could provide the basis for selecting more reasonable treatment protocols.

[Research progress in metabolic and receptor-like nuclear imaging agents for hepatocellular carcinoma].

Hepatocellular carcinoma (HCC) commonly presents with high morbidity and mortality, and early staging diagnosis and timely treatment is pivotal to prolonging patients' survival time. Compared with traditional morphological imaging methods such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), functional imaging methods like single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are playing an increasingly important role in the early diagnosis, efficacy assessment, prognostic evaluation, and treatment planning for HCC, thanks to their higher sensitivity at a molecular level by using various radiopharmaceuticals.

Quantitative meta-analysis of grey matter anomalies in neuropathic pain.

BACKGROUND: Increasing neuroimaging studies have revealed grey matter (GM) anomalies of several brain regions by voxel-based morphometry (VBM) studies in patients with neuropathic pain. The changes have been suggested to be related to central sensitization. Our aim was to investigate concurrence across VBM studies to identify whether different subtypes of neuropathic pain share a common pathophysiological basis revealed by structural abnormalities. METHODS: A systematic search of VBM studies of patients with neuropathic pain and healthy controls published in PubMed and Embase databases from January 2000 to March 2014 was conducted. A quantitative meta-analysis of whole-brain VBM studies in patients with neuropathic pain compared with healthy controls was performed by means of effect-size signed differential mapping. RESULTS: Ten studies comprising 240 patients with neuropathic pain and 263 healthy subjects were systematically included in the present study. Compared to healthy controls, the patients showed consistent decreased GM in bilateral anterior insula and thalamus, right superior frontal gyrus and left postcentral gyrus, and increased GM in right medial frontal gyrus and right posterior insula. The results remained largely unchanged in the following jackknife sensitivity analysis. CONCLUSIONS: This meta-analysis shows strong evidence of brain GM anomalies within the pain matrix in patients with neuropathic pain compared with healthy subjects. Further studies are needed to determine whether the reported changes are specific to neuropathic pain or whether they may be common to other chronic pain.

Gray matter anomalies in anterior cingulate cortex as a correlate of depressive symptoms in drug-naïve idiopathic restless legs syndrome.

BACKGROUND: Depressive symptoms are frequent in idiopathic restless legs syndrome (RLS). However, little is known, so far, about the neurological basis. The present study aimed to explore the neuroanatomical anomalies in depressed drug-naïve RLS patients using voxel-based morphometry (VBM) analysis. METHODS: We recruited 16 drug-naïve idiopathic RLS patients with depressive symptoms (RLS-D), 18 drug-naïve idiopathic RLS patients without depressive symptoms (RLS-ND), and 18 normal controls. All participants underwent structural MRI scans on a 3-T MR system. The differences in regional gray matter (GM) density were determined across groups by VBM8. Additional regression analysis was used to identify any associations between regional GM density and clinical symptoms. RESULTS: GM density of the bilateral anterior cingulate cortex (ACC) was significantly reduced in RLS-D patients when compared to RLS-ND patients or to the healthy controls. However, there were no significant differences of GM density either when the whole RLS group or the RLS-ND group was compared to healthy controls, respectively. Particularly, we found GM density of right ACC was negatively correlated with the severity and duration of depressive symptoms in RLS-D patients. CONCLUSIONS: Depressive symptoms are associated with GM anomalies in ACC in patients with RLS. We propose that ACC is perhaps an important neuroimaging marker for facilitating treatment strategies in patients with RLS when assessing depressive symptoms.

Tubular stomach or whole stomach for esophagectomy through cervico-thoraco-abdominal approach: a comparative clinical study on anastomotic leakage.

BACKGROUND: Esophagectomy through cervico-thoraco-abdominal approach is a useful surgical technique in treating patients with esophageal cancer. However, the cervical reconstruction is also known to have a high rate of anastomotic leakage, as well as anastomotic stricture, intrathoracic stomach syndrome, reflux esophagitis and other complications, thereby influencing postoperative recovery and quality of life. AIMS: The objective of this study was to investigate whether tubular stomach is superior to whole stomach in reducing anastomotic leakage for esophageal reconstruction through the cervico-thoraco-abdominal (3-field) approach. METHODS: A total of 850 patients undergoing the 3-field esophagectomy were retrospectively included in this study and divided into a tubular stomach reconstruction group (Group A, n=453) and a whole stomach reconstruction group (Group B, n=397). All patients underwent esophagectomy through right thorax, left cervical part, abdominal triple incisions and done in esophageal reconstruction by hand-sewn two-layer anastomosis. RESULTS: Results revealed that in comparison with whole stomach, esophageal reconstruction with tubular stomach had a lower incidence of anastomotic leakage (5.5 vs. 9.3%, P<0.05), less manifestation of intrathoracic syndrome (3.3 vs. 9.8%, P<0.001) and less occurence of reflux esophagitis (5.1 vs. 11.1%, P<0.01). However, for the incidence of anastomotic stricture, there was no significant difference between the two groups (9.3 vs. 9.8%). CONCLUSIONS: This observation study suggests that for esophageal cancer patients undergoing the 3-field esophagectomy tubular stomach is better than whole stomach for esophageal reconstruction as reflected by a reduced postoperative anastomotic leakage, intrathoracic syndrome and reflux esophagitis.

Multidrug resistance-associated biomarkers PGP, GST-pi, Topo-II and LRP as prognostic factors in primary ovarian carcinoma.

This study aims to investigate the expression of P-glycoprotein (PGP), glutathione S-transferase pi (GST-pi), DNA topoisomerase II (Topo-II) and lung resistance-related protein (LRP) in ovarian carcinoma, thus providing better chemotherapy choice and post-operative prognosis for ovarian carcinoma patients. A total of 80 primary ovarian carcinoma, 16 benign ovarian epithelial neoplasm, and 12 normal ovarian tissue samples were collected. Immunohistochemistry was used to detect the expression of PGP, GST-pi, Topo-II and LRP, and the results were analysed by correlation with clinicopathological parameters. Positive expression rates of PGP, GST-pi, Topo-II and LRP in patients with ovarian carcinoma (57.5%, 58.8%, 76.3% and 73.8%, respectively) were all higher than those found in normal and benign tissue (P<0.05). In clinical stages I/II vs. III/IV, the expression rates of PGP, GST-pi, Topo-II and LRP were 40.7% vs. 66% (P<0.05), 40.7% vs. 67.9% (P<0.05), 66.7% vs. 81.1% (P>0.05) and 55.6% vs. 83.0% (P<0.05), respectively. Carcinoma differentiation ranged from well to poor, and expression levels of each marker were as follows: PGP, 57.9%, 62.1% and 53.1% (P>0.05); GST-pi, 36.8%, 55.2% and 75.0% (P<0.05); Topo-II, 52.6%, 79.3% and 87.5% (P<0.05); and LRP, 84.2%, 69.0% and 71.9% (P>0.05). Ovarian carcinoma patients with PGP-, GST-pi-, Topo-II- and LRP-positive expression had a shorter median survival time than those who were negative for these markers (PGP: 36 months vs. 48 months [P=0.0017]; GST-pi: 36 months vs. 41 months [P=0.0103]; Topo-II: 37 months vs. 39 months [P=0.3811]; LRP: 37 months vs. 55 months [P=0.002]). COX regression analysis demonstrated that the clinical stage of the tumour, and the expression of PGP, GST-pi or LRP, may influence patient survival time after surgery. The relative death risk for patients with clinical stage III/IV tumours increased 9.46-fold compared to those with stage I/II tumours. The relative death risk in the PGP-, GST-pi- and LRP-positive groups increased by 2.049-, 2.452- or 2.609-fold, respectively, compared with the corresponding negative groups. PGP, GST-pi, Topo-II and LRP are all expressed in primary ovarian carcinoma, indicating the presence of multidrug resistance in this disease. Combined evaluation of PGP, GST-pi, Topo-II and LRP expression may enable better chemotherapeutic choice and provide an accurate prognosis for ovarian carcinoma patients.

Reusable evanescent wave DNA biosensor for rapid, highly sensitive, and selective detection of mercury ions.

Mercury ions (Hg(2+)) are a highly toxic and ubiquitous pollutants requiring rapid and sensitive on-site detection methods in the environment and foods. Herein, we report an envanescent wave DNA-based biosensor for rapid and very sensitive Hg(2+) detection based on a direct structure-competitive detection mode. In this system, a DNA probe covalently immobilized onto a fiber optic sensor contains a short common oligonucleotide sequences that can hybidize with a fluorescently labeled complementary DNA. The DNA probe also comprises a sequence of T-T mismatch pairs that binds with Hg(2+) to form a T-Hg(2+)-T complex by folding of the DNA segments into a hairpin structure. With a structure-competitive mode, a higher concentration of Hg(2+) leads to less fluorescence-labeled cDNA bound to the sensor surface and thus to lower fluorescence signal. The total analysis time for a single sample, including the measurement and surface regeneration, was under 6 min with a Hg(2+) detection limit of 2.1 nM. The high specificity of the sensor was demonstrated by evaluating its response to a number of potentially interfering metal ions. The sensor's surface can be regenerated with a 0.5% SDS solution (pH 1.9) over 100 times with no significant deterioration of performance. This platform is potentially applicable to detect other heavy metal ions or small-molecule analytes for which DNA/aptamers can be used as specific sensing probes.

Monitoring and evaluation of infectious rotaviruses in various wastewater effluents and receiving waters revealed correlation and seasonal pattern of occurrences.

AIMS: Sewage systems are important nodes to monitor enteric pathogens transmitted via water. The aim of this study was to assess the presence of rotaviruses in effluents from wastewater treatment plants (WWTPs) and receiving streams in Beijing, China, to evaluate the reductions of rotaviruses in WWTPs and to provide viral fate and transport data for further epidemiological studies. METHODS AND RESULTS: Two PCR-based methods, including an RT-qPCR and another quantitative RT-PCR (ICC-RT-qPCR), which was integrated with cell culturing, were applied to conduct a 1-year monitoring of infectious rotaviruses and viral genes in effluents from three WWTPs and the receiving waters in Beijing, China. The ICC-RT-qPCR was able to detect more positive samples than RT-qPCR, showing positive results for 67% of primary effluents, 47% of secondary effluents and 14% of tertiary effluents, in comparison with 44, 22 and 6% by RT-qPCR, respectively. Seasonal variations of rotaviruses were observed in all effluents with higher occurrences in winter than in summer, which correlated well with the seasonal pattern of rotaviruses in the river receiving wastewater effluents. The reduction efficiencies by different treatment processes were assessed. Secondary treatments can remove most of infectious rotaviruses in primary sewage, with annual average reduction values of 2·08 ± 0·63, 2·83 ± 0·49 and 2·00 ± 1·10 log(10) for the three WWTPs, respectively. Tertiary treatments were able to further remove infectious rotaviruses. CONCLUSIONS: The results showed a year-round distribution of rotaviruses in three WWTPs in Beijing and provided important information regarding the transport and susceptibility of rotaviruses to different levels of wastewater treatment processes. SIGNIFICANCE AND IMPACT OF THE STUDY: This study, for the first time, revealed the whole year prevalence and reductions of rotaviruses in WWTPs and the corresponding receiving waters in China, and demonstrated the impact of wastewater discharge on the potential spreading of infectious rotaviruses and public health.

Sensitive and rapid chemiluminescence enzyme immunoassay for microcystin-LR in water samples.

A highly sensitive, specific, simple, and rapid chemiluminescence enzyme immunoassay (CLEIA) was developed for the determination of microcystin-LR (MC-LR). Several physicochemical parameters such as the chemiluminescent assay mediums, the dilution ratio of MC-LR-OVA conjugate, monoclonal antibody concentration, and peroxidase labeled antibody concentration were studied and optimized. Under optimum conditions, calibration curve obtained for MC-LR had detection limits of 0.032+/-0.003 microg L(-1), the 50% inhibition concentration (IC50) was 0.20+/-0.02 microg L(-1) and the quantitative detection range was 0.062-0.65 microg L(-1). The proposed methods was successfully applied to the monitoring of MC-LR in spiked water samples without significant effect of the matrix, and the recovery of MC-LR added to water samples at different concentrations ranged from 80% to 115% with the coefficients of variation (CVs) less than 9%. The LOD attained from the calibration curves and the results obtained for the real samples demonstrate the potential use of CLEIA as a screening tool for the analysis of MC-LR in environmental samples.

Portable optical immunosensor for highly sensitive detection of microcystin-LR in water samples.

Fast and sensitive detection of microcystin-LR (MC-LR) was conducted with a portable trace organic pollutant analyzer (TOPA) based on the principle of immunoassay and total internal reflection fluorescence. The reusable fiber optic probe surface was produced by covalently immobilizing a MC-LR-ovalbumin (MC-LR-OVA) conjugate onto a self-assembled thiol-silane monolayer of fiber optic probe through a heterobifunctional reagent. It has been established that the MC-LR-OVA immobilized fiber optic probe is highly resistive to non-specific binding of proteins, while bound anti-MC-LR antibody can easily be eluted from the immunosurface with high recoveries (more than 150 assay cycles) in the way of pepsin solution, without any damage to the surface-immobilized MC-LR derivatives. One assay cycle including surface regeneration was less than 20 min. For the standard curve, the limit of detection (LOD) of 0.03 microg/L and the quantitative detection range of 0.1-10.1 microg/L was obtained when the concentration of antibody labeled by Cy5.5 was 0.28 microg/mL. Cross-reactivity against a few compounds structurally similar to MC-LR was little. The developed immunosensor method was applied to the monitoring of MC-LR in various types of water. The recovery of MC-LR added to water samples at different concentrations ranged from 80 to 110% with relative standard deviation (R.S.D.) values less than 5%. The immunoassay performance of the TOPA was validated with respect to conventional high-performance liquid chromatography, and the correlation between methods was in good agreement (r(2)=0.9978). The TOPA is a portable, easy-to-use, and robust immunoassay system and commercially obtained from the company JQ-environ Co. Ltd. (China).

Sensitive and rapid detection of 2,4-dicholorophenoxyacetic acid in water samples by using evanescent wave all-fiber immunosensor.

Sensitive and rapid detection of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was achieved with a newly developed evanescent wave all-fiber immunosensor (EWAI). A reusable functional sensing surface of the immunosensor is prepared by covalent binding of 2,4-D-bovine serum albumin (2,4-D-BSA) conjugate to a self-assembled alkanethiol monolayer formed onto the fiber optic probe through heterobifunctional reagent. The quantification of free 2,4-D in samples was based on indirect competitive immunoreaction principle. Under optimum conditions, calibration curve obtained for 2,4-D had detection limits of 0.07 microg L(-1), the 50% inhibition concentration (IC(50)) was 3.93+/-0.03 microg L(-1) and the quantitative detection range was 0.22-69.5 microg L(-1). The antibodies binding on the sensor surface could be removed simply by the flow of a pepsin solution (pH 1.9), facilitating reuse of the same probe. The regeneration of the sensor surface allowed the performance of more than 100 assay cycles without significant loss of reactivity. The antibody showed negligible cross-reactivity against a few compounds structurally similar to 2,4-D. The immunosensor developed was successfully applied to the monitoring of 2,4-D in spiked water samples without significant effect of the matrix. The proposed portable immunosensor is promising for real-time on-site analysis of small molecules of environmental interest.

Development of evanescent wave all-fiber immunosensor for environmental water analysis.

A compact and portable evanescent wave all-fiber immunosensor is developed, which employs a novel single-multi-mode fiber optic coupler for exciting and collecting fluorescence emission from the fiber optic probe. Combination tapered fiber probes are produced by tube-etching method and the best tapered ratio of the probe determined is approximately 0.37. Calibration curves obtained for 2,4-dichlorophenoxyacetic acid (2,4-D) and Microcystin-LR (MC-LR) have detection limits of 0.09 microgL(-1)and 0.03 microgL(-1), respectively. The 50% inhibition concentration (IC(50)) for MC-LR and 2,4-D were 1.12+/-0.01 microgL(-1)and 3.81+/-0.03 microgL(-1), respectively. A reusable immunosurface is provided via the covalent attachment of the analyte derivative to a self-assembled monolayer formed onto the fiber optic probe. The regeneration of the sensor surface allows the performance of more than 100 assay cycles within an analysis time of about 20 min for each assay cycle.

Structural and functional design of WWTP operation decision support system with a case study.

This paper developes the WWTP operation decision support system (ODSS) to simulate the dynamic behavior of the WWTP treatment process based on ASMs (activated sludge models) and WWTP experiential knowledge. The novel structure and functions of ODSS can offer more flexible and general instructions to the WWTP operations. The three independent sub-systems, namely expert system, simulation system and training system, can cooperate to achieve many more functions such as operation alert, fault diagnosis, process simulation and so forth. The expert system based on the dynamic simulation, an essential part of WWTP ODSS, has been proved to be feasible and effective by the implementation at Fang Zhuang WWTP. Our results indicated that the WWTP ODSS has significant potential for improving plant performance and reducing treatment costs by assisting the operators at the decision-making level.

Suppression by water extracts of Sophora plants of sucrose-induced hyperglycemia in rats and inhibition of intestinal disaccharidases in vitro.

Partially purified hot-water extracts of the roots of plants of the Sophora family suppressed the increase in blood glucose concentration of rats in the oral sugar tolerance test. The extracts also inhibited rat intestinal sucrase and maltase. The most potent sample was about 15 times more active than catechin, a positive control, in these experiments.