Development of Biaryl-Containing Aldo-Keto Reductase 1C3 (AKR1C3) Inhibitors for Reversing AKR1C3-Mediated Drug Resistance in Cancer Treatment.

Aldo-keto reductase 1C3 (AKR1C3) is correlated with tumor development and chemotherapy resistance. The catalytic activity of the enzyme has been recognized as one of the important factors in inducing anthracycline (ANT) resistance in cancer cells. Inhibition of AKR1C3 activity may provide a promising approach to restore the chemosensitivity of ANT-resistant cancers. Herein, a series of biaryl-containing AKR1C3 inhibitors has been developed. The best analogue S07-1066 selectively blocked AKR1C3-mediated reduction of doxorubicin (DOX) in MCF-7 transfected cell models. Furthermore, co-treatment of S07-1066 significantly synergized DOX cytotoxicity and reversed the DOX resistance in MCF-7 cells overexpressing AKR1C3. The potential synergism of S07-1066 over DOX cytotoxicity was demonstrated in vitro and in vivo. Our findings indicate that inhibition of AKR1C3 potentially enhances the therapeutic efficacy of ANTs and even suggests that AKR1C3 inhibitors may serve as effective adjuvants to overcome AKR1C3-mediated chemotherapy resistance in cancer treatment.

Experimental and Kinetic Study of the Effect of Nitrogen Dioxide on Ethanol Autoignition.

The contribution of NO2 to the ethanol ignition delay time was investigated behind reflected shock waves. The experiments were performed at a pressure of 0.20 MPa, temperature range of 1050-1650 K, equivalence ratio of 0.5/1.0/1.5, and ethanol/NO2 mixing ratios of 100/0, 90/10, and 50/50. The experimental results showed that the addition of NO2 decreased the ignition delay time and promoted the reactivity of ethanol under all equivalence ratios. With an increase in NO2 blending, the effect of equivalence ratio on the ethanol ignition delay time decreased, and with an increase in temperature, the effect of NO2 in promoting ethanol ignition weakened. An updated mechanism was proposed to quantify NO2-promoted ethanol ignition. The mechanism was validated based on available experimental data, and the results were in line with the experimental trends under all conditions. Chemical kinetic analyses were performed to interpret the interactions between NO2 and ethanol for fuel ignition. The numerical analysis indicated that the promotion effect of NO2 is primarily due to an increase of the rate of production and concentration of the radical pool, especially the OH radical pool. The reaction NO + HO2 ⇔ NO2 + OH is key to generating chain-initiating OH radicals.

Development of highly potent and specific AKR1C3 inhibitors to restore the chemosensitivity of drug-resistant breast cancer.

Aldo-keto reductase 1C3 (AKR1C3) is overexpressed in multiple hormone related cancers, such as breast and prostate cancer, and is correlated with tumor development and aggressiveness. As a phase I biotransformation enzyme, AKR1C3 catalyzes the metabolic processes that lead to resistance to anthracyclines, the "gold standard" for breast cancer treatment. Novel approaches to restore the chemotherapy sensitivity of breast cancer are urgently required. Herein, we developed a new class of AKR1C3 inhibitors that demonstrated potent inhibitory activity and exquisite selectivity for closely related isoforms. The best derivative 27 (S19-1035) exhibits an IC50 value of 3.04 nM for AKR1C3 and >3289-fold selectivity over other isoforms. We determined the co-crystal structures of AKR1C3 with three of the inhibitors, providing a solid foundation for further structure-based drug optimization. Co-administration of these AKR1C3 inhibitors significantly reversed the doxorubicin (DOX) resistance in a resistant breast cancer cell line. Therefore, the novel AKR1C3 specific inhibitors developed in this work may serve as effective adjuvants to overcome DOX resistance in breast cancer treatment.

Discovery of Novel Aldo-Keto Reductase 1C3 Inhibitors as Chemotherapeutic Potentiators for Cancer Drug Resistance.

As a crucial target which is overexpressed in a variety of cancers, aldo-keto reductase 1C3 (AKR1C3) confers chemotherapeutic resistance to many clinical agents. However, a limited number of AKR1C3-selective inhibitors are applied clinically, which indicates the importance of identifying active compounds. Herein, we report the discovery, synthesis, and evaluation of novel and potent AKR1C3 inhibitors with structural diversity. Molecular dynamics simulations of these active compounds provide reasonable clarification of the interpreted biological data. Moreover, we demonstrate that AKR1C3 inhibitors have the potential to be superior therapeutic agents for re-sensitizing drug-resistant cell lines to chemotherapy, especially the pan-AKR1C inhibitor S07-2010. Our study identifies new structural classes of AKR1C3 inhibitors and enriches the structural diversity, which facilitates the future rational design of inhibitors and structural optimization. Moreover, these compounds may serve as promising therapeutic adjuvants toward new therapeutics for countering drug resistance.

Construction of in vitro 3-D model for lung cancer-cell metastasis study.

BACKGROUND: Cancer metastasis is the main cause of mortality in cancer patients. However, the drugs targeting metastasis processes are still lacking, which is partially due to the short of effective in vitro model for cell invasion studies. The traditional 2-D culture method cannot reveal the interaction between cells and the surrounding extracellular matrix during invasion process, while the animal models usually are too complex to explain mechanisms in detail. Therefore, a precise and efficient 3-D in vitro model is highly desirable for cell invasion studies and drug screening tests. METHODS: Precise micro-fabrication techniques are developed and integrated with soft hydrogels for constructing of 3-D lung-cancer micro-environment, mimicking the pulmonary gland or alveoli as in vivo. RESULTS: A 3-D in vitro model for cancer cell culture and metastasis studies is developed with advanced micro-fabrication technique, combining microfluidic system with soft hydrogel. The constructed microfluidic platform can provide nutrition and bio-chemical factors in a continuous transportation mode and has the potential to form stable chemical gradient for cancer invasion research. Hundreds of micro-chamber arrays are constructed within the collagen gel, ensuring that all surrounding substrates for tumor cells are composed of natural collagen hydrogel, like the in vivo micro-environment. The 3-D in vitro model can also provide a fully transparent platform for the visual observation of the cell morphology, proliferation, invasion, cell-assembly, and even the protein expression by immune-fluorescent tests if needed. The lung-cancer cells A549 and normal lung epithelial cells (HPAEpiCs) have been seeded into the 3-D system. It is found out that cells can normally proliferate in the microwells for a long period. Moreover, although the cancer cells A549 and alveolar epithelial cells HPAEpiCs have the similar morphology on 2-D solid substrate, in the 3-D system the cancer cells A549 distributed sparsely as single round cells on the extracellular matrix (ECM) when they attached to the substrate, while the normal lung epithelial cells can form cell aggregates, like the structure of normal tissue. Importantly, cancer cells cultured in the 3-D in vitro model can exhibit the interaction between cells and extracellular matrix. As shown in the confocal microscope images, the A549 cells present round and isolated morphology without much invasion into ECM, while starting from around Day 5, cells changed their shape to be spindle-like, as in mesenchymal morphology, and then started to destroy the surrounding ECM and invade out of the micro-chambers. CONCLUSIONS: A 3-D in vitro model is constructed for cancer cell invasion studies, combining the microfluidic system and micro-chamber structures within hydrogel. To show the invasion process of lung cancer cells, the cell morphology, proliferation, and invasion process are all analyzed. The results confirmed that the micro-environment in the 3-D model is vital for revealing the lung cancer cell invasion as in vivo.

Overview of human 20 alpha-hydroxysteroid dehydrogenase (AKR1C1): Functions, regulation, and structural insights of inhibitors.

Human aldo-keto reductase family 1C1 (AKR1C1) is an important enzyme involved in human hormone metabolism, which is mainly responsible for the metabolism of progesterone in the human body. AKR1C1 is highly expressed and has an important relationship with the occurrence and development of various diseases, especially some cancers related to hormone metabolism. Nowadays, many inhibitors against AKR1C1 have been discovered, including some synthetic compounds and natural products, which have certain inhibitory activity against AKR1C1 at the target level. Here we briefly reviewed the physiological and pathological functions of AKR1C1 and the relationship with the disease, and then summarized the development of AKR1C1 inhibitors, elucidated the interaction between inhibitors and AKR1C1 through molecular docking results and existing co-crystal structures. Finally, we discussed the design ideals of selective AKR1C1 inhibitors from the perspective of AKR1C1 structure, discussed the prospects of AKR1C1 in the treatment of human diseases in terms of biomarkers, pre-receptor regulation and single nucleotide polymorphisms, aiming to provide new ideas for drug research targeting AKR1C1.

Nomogram Predicts Improvement of Ischemic Mitral Regurgitation After Coronary Artery Bypass Grafting.

BACKGROUND: Developing a nomogram to predict improvement in moderate ischemic mitral regurgitation (IMR) after coronary artery bypass grafting (CABG) is in need. METHODS: We retrospectively collected data from 112 patients with prior myocardial infarction and moderate IMR undergoing CABG between 2010 and 2018. Patients were divided into 2 groups based on IMR degree 1 year after CABG as follows: Improved Group with no or mild IMR (n = 54) and Failure Group with moderate or severe IMR (n = 58). To determine the predictors of postoperative IMR improvement, preoperative clinical and echocardiographic data were compared, and a nomogram was formulated based on all independent predictors. Discriminative ability, calibration, and clinical usefulness of the prediction model were assessed. RESULTS: Independent predictors of IMR improvement after CABG constructing the nomogram included duration between infarction and operation, posterior-inferior to left ventricular volume ratio, maximum difference of the time to reach minimum systolic volume of 16 segments, P3 leaflet tethering angle, and annular nonplanar angle. The nomogram exhibited well-fitted calibration curves and excellent discriminative ability. The area under the receiver operating characteristic curve was 0.974. Patients with a score >236 demonstrated a high probability of IMR improvement (sensitivity, 90.7%; specificity, 93.1%). Patients in the Improved Group demonstrated greater actuarial survival rates than those in the Failure Group. CONCLUSIONS: The nomogram combining 5 preoperative clinical and echocardiographic predictors provides an accurate preoperative estimation of moderate IMR improvement after surgery, with excellent discriminative ability. Based on this nomogram, patients with a higher score have predicted higher probabilities of IMR improvement.

Myocardial infarction cardiomyocytes-derived exosomal miR-328-3p promote apoptosis via Caspase signaling.

Exosomal miRNAs are used as novel non-invasive biomarkers for detection strategies of human disease. Here, we aimed to investigate the potential clinical value of exosomal miRNAs for myocardial infarction (MI) diagnosis and treatment. Differentially expressed miRNAs were obtained from normal cardiomyocytes, MI cardiomyocytes and adjacent normal cardiomyocytes using miRNA microarray analysis. Exosomes were isolated by centrifugation and identified by transmission electron microscopy (TEM) and western blot. The expression of miR-328-3p in exosomes was then verified by qRT-PCR. Cell apoptosis was measured using flow cytometry and TUNEL analysis. The MI severity was confirmed by masson's trichrome staining and echocardiography. MiR-328-3p was significantly increased in the MI cardiomyocytes and adjacent normal cardiomyocytes. We further confirmed miR-328-3p increasing in the exosomes from MI cardiomyocytes, which can be taken into normal cardiomyocytes. Furthermore, exogenous exosomal miR-328-3p increased apoptosis of cardiomyocytes and promoted MI. Genes regulated by miR-328-3p are mainly enriched in Caspase signaling, which is an important apoptosis regulating signaling pathway. Additionally, Caspase-3 inhibitor, Z-DEVD-FMK, reversed apoptosis and MI promoting function of miR-328-3p. Exosomal miR-328-3p is a potential novel diagnostic biomarker and therapeutic target for MI, and Z-DEVD-FMK could reverse the apoptosis progression induced by miR-328-3p.

Feasibility of radical gastrointestinal tumor resection with simultaneous off-pump coronary artery bypass surgery for patients with severe heart problems: A retrospective cohort study from a single institutional database.

PURPOSE: Clinical treatment of gastrointestinal neoplasms in patients with severe coronary stenosis is difficult, and it remains controversial to perform staged or simultaneous surgeries. The purpose of this study was to retrospectively analyze the feasibility and indications for simultaneous gastrointestinal tumor resection and off-pump coronary artery bypass (OPCAB) graft surgery. METHODS: Data collected from a total of five patients, including three patients with gastric cancer and two patients with colorectal cancer, who underwent simultaneous radical cancer resection and OPCAB between September 2010 and October 2019, were retrospectively analyzed. Among these patients, one had an incomplete colonic obstruction. All patients had severe coronary stenosis, and one experienced acute heart failure before surgery. OPCAB was performed first, followed by the radical cancer resection. RESULTS: All five patients were discharged from hospital without perioperative death, major cardiovascular events or anastomotic leakage. The mean postoperative hospital stay was 9.4 days. One patient experienced slight gastrointestinal bleeding after surgery, which improved with conservative treatment. After a mean follow-up of 39 months, two patients with gastric cancer died from tumor metastasis at 28 months and 37 months, while the remaining three patients did not have tumor recurrence or metastasis. None of the patients experienced myocardial ischemia. CONCLUSION: It is safe and feasible to perform simultaneous OPCAB and gastrointestinal surgeries on the premise of strictly controlling the indications for patients with gastrointestinal tumors complicated with severe coronary artery stenosis.

Feasibility of off-pump coronary artery grafting for patients with impaired left ventricular ejection fraction: A retrospective cohort study from a single institutional database.

OBJECTIVE: Despite substantial advances in surgical practice, the management of patients with impaired left ventricular ejection fraction (LVEF) remains challenging. Furthermore, evidence on the outcomes of off-pump coronary artery bypass (OPCAB) surgery in this population is inconsistent. We conducted the present study to compare the short- and long-term outcomes of OPCAB in patients with different ejection fractions. METHODS: This retrospective cohort study used data from the Hua-Shan Cardiac Surgery and included consecutive patients aged ≥ 18 years who underwent OPCAB procedures during 2016-2019. The patients included in the study were followed up until death or the end of data collection. Patients with different ejection fractions were matched 1:2 using propensity score matching. Factors associated with short-term outcomes were determined using logistic regression, and Kaplan-Meier survival analyses for the differences in all-cause death were generated. RESULTS: The two propensity score matched groups consisted of 40 left ventricular dysfunction (LVD) and 80 normal left ventricular function (NLVF) patients. No significant intergroup differences were observed in the postoperative outcomes for the occurrence of left heart failure (22.5% in LVD vs. 5.0% in NLVF, p = .009). Age (odds ratio = 1.11, 95% confidence interval = 1.04-1.18) but not the preoperative LVEF was shown to be a strong predictor of short-term events in logistic regression analyses. Kaplan-Meier curves displayed similar freedom from all-cause death (p = .119) or cardio-death (p = .092) between groups. CONCLUSION: The immediate postoperative outcomes and long-term outcomes were similar between the groups, indicating that OPCAB is a safe and effective choice for patients with LVD.

Novel controlled and targeted releasing hydrogen sulfide system exerts combinational cerebral and myocardial protection after cardiac arrest.

BACKGROUND: Cardiac arrest (CA) is a leading cause of death worldwide. Even after successful cardiopulmonary resuscitation (CPR), the majorities of survivals are companied with permanent myocardial and cerebral injury. Hydrogen sulfide (H2S) has been recognized as a novel gasotransmitter exerting multiple organ protection; however, the lacks of ideal H2S donors which can controlled release H2S to targeted organs such as heart and brain limits its application. RESULTS: This work utilized mesoporous iron oxide nanoparticle (MION) as the carriers of diallyl trisulfide (DATS), with polyethylene glycol (PEG) and lactoferrin (LF) modified to MIONs to acquire the prolonged circulation time and brain-targeting effects, and a novel targeted H2S releasing system was constructed (DATS@MION-PEG-LF), which exhibited excellent biocompatibility, controlled-releasing H2S pattern, heart and brain targeting features, and the ability to be non-invasive traced by magnetic resonance imaging. DATS@MION-PEG-LF presented potent protective effects against cerebral and cardiac ischemic injury after CA in both in vitro hypoxia/reoxygenation models and in vivo CA/CPR models, which mainly involves anti-apoptosis, anti-inflammatory and anti-oxidant mechanisms. Accordingly, the cardiac and cerebral functions were obviously improved after CA/CPR, with potentially improved survival. CONCLUSIONS: The present work provides a unique platform for targeted controlled release of H2S based on MIONs, and offers a new method for combinational myocardial and cerebral protection from ischemic injury, bringing considerable benefits for CA patients.

Overexpression of microRNA-23a-5p induces myocardial infarction by promoting cardiomyocyte apoptosis through inhibited of PI3K/AKT signalling pathway.

Myocardial infarction (MI) leads to cardiac remodelling and heart failure. Cardiomyocyte apoptosis is considered a critical pathological phenomenon accompanying MI, but the pathogenesis mechanism remains to be explored. MicroRNAs (miRs), with the identity of negative regulator of gene expression, exist as an important contributor to apoptosis. During the experiment of this study, MI mice models were successfully established and sequencing data showed that the expression of miR-23a-5p was significantly enhanced during MI progression. Further steps were taken and it showed that apoptosis of cardiac cells weakened as miR-23a-5p was downregulated and on the contrary that apoptosis strengthened with the overexpression of miR-23a-5p. To explore its working mechanisms, bioinformatics analysis was conducted by referring to multi-databases to predict the targets of miR-23a-5p. Further analysis suggested that those downstream genes enriched in several pathways, especially in the PI3K/Akt singling pathway. Furthermore, it demonstrated that miR-23a-5p was negatively related to the phosphorylation of PI3K/Akt, which plays a critical role in triggering cell apoptosis during MI. Recilisib-activated PI3K/Akt singling pathway could restrain apoptosis from inducing miR-23a-5p overexpression, and Miltefosine-blocked PI3K/Akt singling pathway could restrict apoptosis from inhibiting miR-23a-5p reduction. In conclusion, these findings revealed the pivotal role of miR-23a-5p-PI3K/Akt axis in regulating apoptosis during MI, introducing this novel axis as a potential indicator to detect ischemic heart disease and it could be used for therapeutic intervention.

[Effect of rivaroxaban on the injury during endotoxin-induced damage to human umbilical vein endothelial cells].

OBJECTIVE: To evaluate the effect and mechanism of rivaroxaban, an inhibitor of coagulation factor Xa (FXa), on endotoxin-induced injury to human umbilical vein endothelial cells (HUVEC). METHODS: When cultured HUVEC grow to 80% fusion, they were divided into four groups according to the random number method: blank control group (DMEM medium), lipopolysaccharide (LPS) group (cells were challenged by 100 µg/L LPS for 16 hours), FXa+LPS group (cells were challenged by LPS for 16 hours after they were cultured with 100 nmol/L FXa for 24 hours), and FXa +RIV+LPS group (cells were challenged by LPS for 16 hours after they were cultured with 100 nmol/L FXa and 1 µmol/L rivaroxaban for 24 hours). After each group of cells were challenged with LPS, the cell activity was detected by the cell proliferation and toxicity kit (CCK-8); the cell migration ability was detected by cell scratch experiments; the abilities of cells migration were measured by scratch-wound-healing assay; the apoptosis of cells were evaluated using flow cytometry; the endothelial barrier of cells was assessed by Transwell and Evans blue; the levels of tumor necrosis factor-α (TNF-α), interleukin (IL-1ß, IL-6) were detected by the enzyme linked immunosorbent assay (ELISA); the expressions of nuclear factor-ΚB (NF-ΚB) and mitogen activated protein kinase (MAPK) signaling pathway were detected by Western Blot. RESULTS: Compared with blank control group, the cell viability in LPS group was significantly decreased, and the migration ability, number of apoptotic cells, and barrier permeability of endothelial cells was significantly increased, the levels of TNF-α, IL-1ß and IL-6 were significantly increased, and the expressions of phosphorylation of c-Jun N-terminal kinase (p-JNK), phosphorylation of p38MAPK (p-p38MAPK), phosphorylation of transforming growth factor kinase 1 (p-TAK1) and phosphorylation of NF-ΚBp65 (p-NF-ΚBp65) were significantly increased. It indicated that LPS could stimulate the inflammatory response of vascular endothelial cells, and had a significant impact on cell activity, apoptosis and function. There was no significant difference in above indexes between FXa+LPS group and LPS group, except for the level of IL-6 being higher in FXa+LPS group. Compared with FXa+LPS group, in FXa+RIV+LPS group, the cell activity was significantly increased (A value: 0.42±0.02 vs. 0.33±0.02), and migration ability was significantly decreased (folds: 1.78±0.17 vs. 2.24±0.20), the number of apoptotic cells was significantly decreased [(11.30±0.70)% vs. (21.03±0.19)%], and permeability of monolayers endothelial cells was significantly decreased [(149±12)% vs. (253±15)%], the levels of inflammatory cytokines were significantly decreased [IL-1ß (ng/L): 163.2±20.7 vs. 477.8±20.2, IL-6 (ng/L): 69.3±0.5 vs. 238.0±24.1, TNF-α (ng/L): 117.0±13.1 vs. 196.2±4.5], the expressions of p-TAK1 and p-NF-ΚBp65 were significantly decreased (p-TAK1/TAK1: 0.74±0.09 vs. 1.85±0.15, p-NF-ΚBp65/NF-ΚBp65: 1.15±0.17 vs. 2.36±0.20), with statistically significant differences (all P < 0.05). There was no significant difference in the p-JNK, p-p38MAPK expressions between FXa+RIV+LPS group and FXa+LPS group (p-JNK/JNK: 1.64±0.12 vs. 1.65±0.15, p-p38MAPK/p38MAPK: 2.31±0.32 vs. 2.35±0.20, both P > 0.05). CONCLUSIONS: Rivaroxaban can effectively relieve the inflammatory response of HUVEC stimulated by LPS, which may be related to the inhibition of NF-ΚB signaling pathway activation rather than MAPK signaling pathway.

Donor heart preservation with a novel long-term and slow-releasing hydrogen sulfide system.

Cardiac transplantation has been limited by the inability to long preserve donor hearts safely. Hydrogen sulfide (H2S) has been recognized as an important gasotransmitter exerting potent cardioprotection from ischemia/reperfusion injury (I/R). Herein we investigated the cardioprotective effects of a novel long-term and slow-releasing H2S system, namely DATS-MSN, in heart preservation solution using a heart transplantation models. The release of H2S from DATS-MSN was slow and continuous in the University of Wisconsin solution (UW), correspondingly, DATS-MSN application demonstrated superior cardioprotective effects over the control and traditional H2S donors after 6 h heart preservation and 1 h reperfusion, associated with greater allograft performance including left ventricular developed pressure (LVDP) and dP/dt max, reduced plasmic CK-MB and troponin I levels, inhibited myocardial inflammation, increased antioxidant enzyme activities, preserved mitochondria structure and function, and decreased cardiomyocyte apoptosis index. Also, DATS-MSN application presented significant superiority in long-term allografts survival and function after 8 weeks of transplantation. In the in vitro experiments, cardiomyocytes injury from hypoxia was found to be relived with the treatment of DATS-MSN by anti-inflammatory effects via TLR4/NLRP3 pathway. The present work provides a long-term releasing H2S donor compatibly applied in the donor heart preservation, and preliminary explores its underlying mechanisms.

miR-130 aggravates acute myocardial infarction-induced myocardial injury by targeting PPAR-γ.

Cardiac remodeling is a common pathophysiological change associated with acute myocardial infarction (AMI). Recent evidence indicates that microRNAs are strong posttranscriptional regulators which play an important role in regulating the microenvironment of myocardial tissue after AMI. In this study, we sought to explore the potential role and underlying mechanism of miR-130 in AMI. H9c2 cells were cultured under hypoxic conditions to simulate myocardial infarction. The influence of aberrantly expressed miR-130 on H9c2 cells under hypoxia was also estimated with RT-PCR, western blot and enzyme-linked immunosorbent assay. Using bioinformatics methods, of miR-130 target genes were verified with luciferase reporter assay. Then, the effects of miR-130 on AMI were identified in an induced myocardial injury model in rats. The results show that miR-130 downregulation remarkably decreased hypoxia-induced inflammation and fibrosis related protein expression in H9c2 cells and reversed hypoxia-induced peroxisome proliferator-activated receptor γ (PPAR-γ) inhibition. A bifluorescein reporter assay further confirmed that PPAR-γ was a target gene of miR-130. This study verified that PPAR-γ has a cardioprotective effect by inhibiting NFκB-mediated inflammation and TGF-ß1-mediated fibrosis. In vivo experiments confirmed that downregulation of miR-130 expression promotes PPAR-γ-mediated cardioprotective effects by suppressing inflammation and myocardial fibrosis. Taken together, these findings suggest that miR-130 knockdown alleviates infarction-induced myocardial injury by promoting PPAR-γ expression.

Correlation Among Soil Enzyme Activities, Root Enzyme Activities, and Contaminant Removal in Two-Stage In Situ Constructed Wetlands Purifying Domestic Wastewater.

Two-stage in situ wetlands (two vertical flow constructed wetlands in parallel and a horizontal flow constructed wetland) were constructed for studying domestic wastewater purification and the correlations between contaminant removal and plant and soil enzyme activities. Results indicated the removal efficiency of NH4 (+) and NO3 (-) were significantly correlated with both urease and protease activity, and the removal of total phosphorus was significantly correlated with phosphatase activity. Chemical oxygen demand removal was not correlated with enzyme activity in constructed wetlands. Plant root enzyme (urease, phosphatase, protease and cellulose) activity correlation was apparent with all contaminant removal in the two vertical flow constructed wetlands. However, the correlation between the plant root enzyme activity and contaminant removal was poor in horizontal flow constructed wetlands. Results indicated that plant roots clearly played a role in the removal of contaminants.

The influence of lung ischemia-reperfusion injury on myocardium.

OBJECT: To investigate the effect of lung Ischemia-reperfusion injury on cardiac muscle. METHODS: SD rats were randomly divided into the following four groups: sham operation group (TS group); experimental control group (TG group); curcumin group (TC group); dexamethasone group (TM group). After 4 h and 24 h of lung ischemia-reperfusion, the cardiac muscle was collected. We measured the concentrations of TNF-α, IL-6, caspase-3, antioxidant capacity and neutrophil infiltration in myocardial tissue. RESULTS: After lung ischemia-reperfusion 4 h, TNF-α, IL-6 levels, MDA and neutriphils infiltration increased in myocardial tissue in control group, total antioxidant capacity decreased, and caspase-3 exhibited no significant changes. However, 24 h after reperfusion, there were no significant difference between the sham group and experimental group. CONCLUSION: Lung ischemia-reperfusion injury affected the function of cardiac muscle, especially 4 h after reperfusion. Curcumin and dexamethasone effectively protected myocardial injury after lung ischemia-reperfusion.