Detection of PCBs and OCPs in the Irtysh River Water (GC-MS/MS) and ecological risk assessment.

This study optimized a gas chromatography-tandem triple quadrupole mass spectrometry (GC-MS/MS) method for the determination of 21 persistent organic pollutants (POPs) in Irtysh River water, including 14 organochlorines (OCPs) and 7 polychlorinated biphenyls (PCBs). Factors such as column temperature ramping, selection of qualitative and quantitative ion pairs and collision energy were considered to achieve perfect separation and accurate quantification of all 21 target compounds. The limits of detection (LOD) for PCBs and OCPs ranged from 0.21 to 1.18 ng/L. Applying this method to detect POPs in the Irtysh River revealed concentrations of OCPs ranging from ND to 20.2 ng/L and PCBs from ND to 0.411 ng/L. Source analysis indicated that POPs in the Irtysh River mainly originate from historical industrial and agricultural activities, particularly the deliberate use of pesticides. To ensure ecological safety and human health, expanding the range of target analytes and monitoring periods is necessary. This study provides:•Qualitative and quantitative analysis methods for 7 PCBs and 14 OCPs.•Recoveries achieved ranged between 74.6 to 109 % with RSD less than 15 %.•Analysis of sources, transport pathways, accumulation status, and ecological risks of PCBs and OCPs in the Irtysh River.

Transplantation of magnetically labeled mesenchymal stem cells improves cardiac function in a swine myocardial infarction model.

BACKGROUND: Mesenchymal stem cells (MSCs) transplantation provides a new approach for myocardial repair. However, many important fundamental questions about MSCs transplantation remain unanswered. There is an urgent need to identify MSCs from the beating heart and analyze the efficacy of this new approach. This study aimed to localize the magnetically labeled MSCs (MR-MSCs) and monitor the restorative effects of MR-MSCs with magnetic resonance (MR) imaging. METHODS: Acute myocardial infarction (AMI) was created in swine by a balloon occlusion of the left anterior descending coronary artery. Cells were delivered via intracoronary infusion after myocardial infarction. Infarct size change and cardiac function were assessed with 3.0T MR scanner. The results were then confirmed by histological and western blot analysis. All statistical procedures were performed with Systat (SPSS version 12.01). RESULTS: A total of 26 swine were divided into four groups (sham-operated group, n=6; AMI group with PBS transplantation, n=6; labeled MSCs group, n=7; unlabeled MSCs group, n=7). MSCs, MR-MSCs (10(7) cells) or PBS were delivered by intracoronary injection after MI and serial cardiac MR imaging studies were performed at 0, 4 and 8 weeks after transplantation. MR imaging demonstrated MI size decreased after MSCs transplantation in labeled and unlabeled groups, however, increases were seen in the AMI group at 8 weeks after MI. The left ventricular ejection fraction (LVEF) was slightly increased in the AMI group ((41.87+/-2.45)% vs (39.04+/-2.80)%, P>0.05), but significantly improved in the MR-MSCs group ((56.85+/-1.29)% vs (40.67+/-2.00)%, P<0.05) and unlabeled group ((55.38+/-1.07)% vs (41.78+/-2.08)%, P<0.05) at 8 weeks after treatment. MR-MSCs were further confirmed by Prussian blue and immunofluorescent staining. Western blot analysis demonstrated that there was an increased expression of cardiomyocyte markers such as myosin heavy chain and troponin T in the MSCs treatment groups and the ratio of matrix metalloproteinase 2 to tissue inhibitor of metalloproteinase 1 decreased in the labeled group and unlabeled group compared with the AMI group and sham-operated group. CONCLUSION: Transplanted MR-MSCs can regenerate new myocardium and prevent remolding in an MI model at 2-month follow-up and represent a preferred method to better understand the mechanisms of stem cell therapy in future clinical studies.

[Therapeutic effects of magnetically labeled mononuclear and mesenchymal stem cells transplantation in a swine myocardial infarction model assessed by magnetic resonance imaging].

OBJECTIVE: To evaluate the therapeutic effects of magnetically labeled mononuclear stem cells (MR-MNC) and mesenchymal stem cells (MR-MSC) transplantation in a swine acute myocardial infarction (AMI) model by MR imaging. METHODS: AMI model was established in swines by balloon occlusion of the left anterior descending coronary artery, 10(7) autologous MR-MSC (n = 7), MR-MNC (n = 6) or PBS (n = 6) were delivered via intracoronary infusion within 1 week after AMI [(4.8 +/- 1.3) days]. Changes of infarct size and cardiac function were assessed with the use of 3.0T MR scanner before AMI, at 1 and 8 weeks post AMI. RESULTS: Magnetically labeled stem cells could be identified in the region of AMI by cardiac MR imaging. Eight weeks post transplantation, infarct size was significantly reduced in MR-MSC transplantation group (8.5% +/- 0.5% vs. 24.7% +/- 3.1%, P < 0.05) and in MR-MNC transplantation (12.3% +/- 1.5% vs. 26.1% +/- 1.5%, P < 0.05) while infarct size remained unchanged in PBS group (P > 0.05) compared to values at 1 week post AMI, left ventricular ejection fraction (LVEF) was also significantly higher in MR-MSC transplantation group (56.9% +/- 1.3% vs. 40.7% +/- 2.0%, P < 0.05) and MR-MNC transplantation group (52.8% +/- 1.4% vs. 41.9% +/- 3.3%, P < 0.05) compared to LVEF at 1 week post AMI. LVEF increase was more significant in swines received MR-MSC transplantation than MR-MNC transplantation (16.2% +/- 1.2% vs. 10.9% +/- 3.0%, P < 0.05). Prussian blue staining identified stem cells in corresponding myocardial regions with as by MRI. Western blot analysis demonstrated that cardiac expressions of myosin heavy chain (MHC) in MR-MSC group (100.3 +/- 5.5) and in MR-MNCs group (95.5 +/- 4.2) were significantly higher than that in PBS group (75.7 +/- 5.7, P < 0.05), myocardial troponin T (cTNT) expression in MR-MSC group (124.0 +/- 5.8) and MR-MNC group (118.4 +/- 4.4) were also significantly higher than in PBS group (93.3 +/- 3.9, P < 0.05) while MMP2/TIMP1 ratios in MR-MSC group (0.6 +/- 0.1) and MR-MNC group (0.6 +/- 0.1) were significantly lower than that in PBS group (4.2 +/- 0.2, P < 0.05). CONCLUSIONS: Magnetically labeled MR-MSC and MR-MNC homed to heart post myocardial infarction and reduced infarct size, improved cardiac function. MR-MSC is superior to MR-MNC on improving cardiac function.

Daikenchuto (Da-Jian-Zhong-Tang) ameliorates intestinal fibrosis by activating myofibroblast transient receptor potential ankyrin 1 channel.

AIM: To investigate the anti-fibrotic effects of the traditional oriental herbal medicine Daikenchuto (DKT) associated with transient receptor potential ankyrin 1 (TRPA1) channels in intestinal myofibroblasts. METHODS: Inflammatory and fibrotic changes were detected in a 2,4,6-trinitrobenzenesulfonic acid (TNBS) chronic colitis model of wild-type and TRPA1-knockout (TRPA1-KO) mice via pathological staining and immunoblotting analysis. Ca2+ imaging experiments examined the effects of DKT and its components/ingredients on intestinal myofibroblast (InMyoFib) cell TRPA1 channel function. Pro-fibrotic factors and transforming growth factor (TGF)-ß1-associated signaling were tested in an InMyoFib cell line by qPCR and immunoblotting experiments. Samples from non-stenotic and stenotic regions of the intestines of patients with Crohn's disease (CD) were used for pathological analysis. RESULTS: Chronic treatment with TNBS caused more severe inflammation and fibrotic changes in TRPA1-KO than in wild-type mice. A one-week enema administration of DKT reduced fibrotic lesions in wild-type but not in TRPA1-KO mice. The active ingredients of DKT, i.e., hydroxy α-sanshool and 6-shogaol, induced Ca2+ influxes in InMyoFib, and this was antagonized by co-treatment with a selective TRPA1 channel blocker, HC-030031. DKT counteracted TGF-ß1-induced expression of Type I collagen and α-smooth muscle actin (α-SMA), which were accompanied by a reduction in the phosphorylation of Smad-2 and p38-mitogen-activated protein kinase (p38-MAPK) and the expression of myocardin. Importantly, 24-h incubation with a DKT active component Japanese Pepper increased the mRNA and protein expression levels of TRPA1 in InMyoFibs, which in turn negatively regulated collagen synthesis. In the stenotic regions of the intestines of CD patients, TRPA1 expression was significantly enhanced. CONCLUSION: The effects of DKT on the expression and activation of the TRPA1 channel could be advantageous for suppressing intestinal fibrosis, and benefit inflammatory bowel disease treatment.

[MR imaging of injected magnetically labeled stem cells in myocardial infarction: experiment with pigs].

OBJECTIVE: To investigate the efficacy of magnetic resonance imaging (MRI) in tracking bone marrow derived mononuclear cells (BM-MNCs) labeled with superparamagnetic iron oxide (SPIO) nanoparticles. METHODS: BM-MNCs were isolated from the bone marrow of 14 pigs. These 14 pigs underwent occlusion of the left anterior descending coronary artery (LAD) to establish myocardial infarction (MI) models and then randomly divided into 2 groups: experimental group (n = 9) to be injected with BM-MNCs labeled with SPIO intracoronarily under X-ray fluoroscopy, and control group (n = 5), to be injected with unlabelled BM-MNCs MRI was performed with a 1.5T MR scanner to demonstrate the location of the BM-MNCs once a week. T pigs were killed when no labeled BM-MSC was detected. The hearts were taken out to undergo HE staging and Prussian blue staining. Immunohistochemistry was used to detect the desmin and myosin. RESULTS: The cell labeling efficiency was almost 100%. Contrast-enhanced MRI demonstrated successful establishment of MI models. Effective MRI tracking findings were obtained in 8 pigs, 7 of the experimental group and 3 of the control group. In 3 pigs T2* weighted MRI showed the zone of labeled cell accumulation shows vague low-signal area around the infarction area and much better conspicuity of the zone of hypoenhancement was shown under contrast-enhanced MRI. The hypoenhancement zone disappeared 14 - 21 days after the injection of BM-MSCs. Histological analyses showed that most Prussian blue positive cells were well correlated with the area where a signal intensity loss was observed in MRI. CONCLUSION: 1.5T MR imaging can monitor the magnetically labeled BM-MNC in vivo in myocardial infarction provided the number of injected is nor less than 10(6).

Efficiently tracking of stem cells in vivo using different kinds of superparamagnetic iron oxide in swine with myocardial infarction.

BACKGROUND: Superparamagnetic iron oxide (SPIO) particles have shown much promise as a means to visualize labeled cells using molecular magnetic resonance imaging (MRI). Micrometer-sized superparamagnetic iron oxide (MPIO) particles and nanometer-sized ultrasmall superparamagnetic iron oxide (USPIO) are two kinds of SPIO widely used for monitoring stem cells migration. Here we compare the efficiency of two kinds of SPIO during the use of stem cells to treat acute myocardial infarction (AMI). METHODS: An AMI model in swine was created by 60 minutes of balloon occlusion of the left anterior descending coronary artery. Two kinds of SPIO particles were used to track after intracoronary delivered 10(7) magnetically labeled mesenchymal stem cells (MR-MSCs). The distribution and migration of the MR-MSCs were assessed with the use of 3.0T MR scanner and then the results were confirmed by histological examination. RESULTS: MR-MSCs appeared as a local hypointense signal on T2*-weighted MRI and there was a gradual loss of the signal intensity after intracoronary transplantation. All of the hypointense signals in the USPIO-labeled group were found on T2*-weighted MRI, contrast to noise ratio (CNR) decreased in the MPIO-labeled group (16.07 ± 5.85 vs. 10.96 ± 1.34) and USPIO-labeled group (11.72 ± 1.27 vs. 10.03 ± 0.96) from 4 to 8 weeks after transplantation. However, the hypointense signals were not detected in MPIO-labeled group in two animals. MRI and the results were verified by histological examination. CONCLUSIONS: We demonstrated that two kinds of SPIO particles in vitro have similar labeling efficiency and viability. USPIO is more suitable for labeling stem cells when they are transplanted via a coronary route.

Identification and differentiation of magnetically labeled mesenchymal stem cells in vivo in swines with myocardial infarction.

We aim to track mesenchymal stem cells (MSCs) after magnetically labeling and test the ability of these cells differentiate into cardiomyocytes in vivo. Therefore, 20 swines were divided into four groups, sham-operated group (n=3); acute myocardial infarction (AMI) transplanted with PBS (n=3); labeled MSCs (n=7) and unlabeled MSCs (n=7) group. 10(7) labeled or unlabeled cells were intracoronary delivered after MI (4.8+/-1.3 days), and serial cardiac MR (3.0T) imaging studies were performed at 0, 4 and 8 weeks after transplantation, then the results were confirmed by histological and western blot analysis. We demonstrated that labeled MSCs can be reliably detected and tracked in vivo using MR imaging. In particular, we provided the evidence of regeneration of labeled MSCs in vivo by histological examination and western blot analysis.