Removal of NO in flue gas simulated by the Fe2+/Cu2+-activated double oxidant system

⋅ O H The wet denitrification technology has a good development prospect due to its simple system and mild reaction conditions, and related research has become a hot topic in the field of flue gas purification. In this work, a novel simultaneous removal technology of NO from flue gas using Fe2+/Cu2+-catalytic H2O2/(NH4)2S2O8 system was developed for the first time. The feasibility of this new flue gas cleaning technology was explored through a series of experiments and performance analyses. The mechanism of oxidation products, free radicals and simultaneous removal of NO was revealed. The effects of the main process parameters on the removal of NO were investigated. Relevant results demonstrated that the removal efficiency of NO was elevated when the concentration of (NH4)2S2O8 or reacting temperature increased, while it was decreased after increasing the raising of Fe2+, Cu2+ and H2O2 concentrations. The main radicals were and·S O 4 - , using the electron spin resonance technique in the solution, and played a very important role in NO removal. The main products were carried out by ion chromatography and elemental N material accountancy, and the results showed that it was sulfate and nitrate in the solution, which provided theoretical guidance for the subsequent treatment and resource utilization of the absorption solution. The results of the study provided a theoretical basis for the industrial application of wet denitrification.Highlights A new green process of NO removal by a wet process with Fe2+/Cu2+ activated (NH4)2S2O8 system is proposed in this paper;Elimination mechanisms and paths of NO are elucidated;The synergistic role produced by Cu2+ and Fe2+ is beneficial to the purification of NO;The synergistic role produced by (NH4)2S2O8 and H2O2 increased the concentration of free radicals in the solution;This process jointly considers the enhanced removal of NO and recycling of transition metal ions.

Formyl peptide receptor 2 activation by mitochondrial formyl peptides stimulates the neutrophil proinflammatory response via the ERK pathway and exacerbates ischemia-reperfusion injury

BACKGROUND

Ischemia-reperfusion injury (IRI) is an inevitable process in renal transplantation that significantly increases the risk of delayed graft function, acute rejection, and even graft loss. Formyl peptide receptor 2 (FPR2) is an important receptor in multiple septic and aseptic injuries, but its functions in kidney IRI are still unclear. This study was designed to reveal the pathological role of FPR2 in kidney IRI and its functional mechanisms.

METHODS

To explore the mechanism of FPR2 in kidney IRI, the model rats were sacrificed after IRI surgery. Immunofluorescence, enzyme-linked immunosorbent assays, and western blotting were used to detect differences in the expression of FPR2 and its ligands between the IRI and control groups. WRW₄ (WRWWWW-NH2), a specific antagonist of FPR2, was administered to kidney IRI rats. Kidney function and pathological damage were detected to assess kidney injury and recovery. Flow cytometry was used to quantitatively compare neutrophil infiltration among the experimental groups. Mitochondrial formyl peptides (mtFPs) were synthesized and administered to primary rat neutrophils together with the specific FPR family antagonist WRW₄ to verify our hypothesis in vitro. Western blotting and cell function assays were used to examine the functions and signaling pathways that FPR2 mediates in neutrophils.

RESULTS

FPR2 was activated mainly by mtFPs during the acute phase of IRI, mediating neutrophil migration and reactive oxygen species production in the rat kidney through the ERK1/2 pathway. FPR2 blockade in the early phase protected rat kidneys from IRI.

CONCLUSIONS

mtFPs activated FPR2 during the acute phase of IRI and mediated rat kidney injury by activating the migration and reactive oxygen species generation of neutrophils through the ERK1/2 pathway.

Effects of MoO3 and CeO2 doping on the decomposition and reactivity of NH4HSO4 on V2O5/TiO2 catalysts

The deposition of NH₄HSO₄ on catalysts is one of the key issues for selective catalytic reduction of NO_x. In this study, NH₄HSO₄ was preloaded on catalysts, and the effects of MoO₃ and CeO₂ doping on the decomposition and reactivity of NH₄HSO₄ on V₂O₅/TiO₂ catalysts are studied. The results show that the introduction of MoO₃ and CeO₂ significantly promoted NO_x conversion on the V₂O₅/TiO₂ catalysts. Doping with MoO₃ could effectively enhance the S and H₂O resistance of the catalysts. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis indicate that it is the strong chemical interactions between NH₄HSO₄ and the catalysts that are adverse to the decomposition of NH₄HSO₄. However, doping with MoO₃ apparently inhibits these interactions, which significantly decrease the decomposition temperature of NH₄HSO₄. In situ FTIR experiments show that the NH₄⁺ in preloaded NH₄HSO₄ could react with gaseous NO on catalysts, and doping with MoO₃ could facilitate the reaction rate.

Modelling of ammonia recovery from wastewater by air stripping in rotating packed beds

The processes of ammonia recovery from ammonia nitrogen containing wastewater by air stripping in the laboratory-scale and the pilot-scale rotating packed bed (RPB) were simulated by the Aspen with the module of RADFRAC. For a more accurate description of the model, a variety of correlations for the RPB were introduced into the Aspen by the FORTRAN, such as the gas-liquid mass transfer rate, the liquid holdup, the heat transfer rate and the effective gas-liquid interfacial area, etc. The predicted data of ammonia recovery rate were consistent with the experimental results. To further optimize the operating conditions of ammonia recovery, the research also covered the effects of high gravity factor, gas to liquid ratio, pH and temperature on ammonia recovery rate. The promising results had suggested the established model could serve as a powerful tool to simulate the processes of ammonia recovery from the ammonia nitrogen containing wastewater by air stripping in the laboratory-scale and the pilot-scale RPB.

Diagnosis and Treatment of Early Transplant Renal Artery Stenosis: Experience From a Center in Eastern China

Few studies have focused on the clinical characteristics of transplant renal artery stenosis (TRAS) with early onset. Sixteen cases diagnosed with TRAS in our center from January 2014 to August 2018 were retrospectively analyzed. Sixteen transplant patients without TRAS were selected as controls. The median diagnostic time for TRAS was 47.5 days after transplantation. No significant difference was observed between the TRAS group and the control group. The serum creatinine level (Scr), estimated glomerular filtration rate, systolic/diastolic blood pressure, graft artery peak systolic velocity (PSV), and resistive index of intersegmental artery (RI-ISA) between the 2 groups were (5.55 ± 3.49) and (1.89 ± 0.85) mg/dL; (17.83 ± 14.94) and (49.39 ± 19.96) mL/min; (143.50 ± 9.49)/(86.14 ± 7.38) and (130.38 ± 18.86)/(82.81 ± 12.52) mm Hg; (3.39 ± 1.57) and (1.31 ± 0.51) m/s; and (0.51 ± 0.10) and (0.67 ± 0.13), respectively. All showed statistical significance except the diastolic blood pressure. The Scr, estimated glomerular filtration rate, systolic/diastolic blood pressure, graft artery PSV, and RI-ISA in the TRAS group prior and after treatment were (5.55 ± 3.49) and (3.20 ± 1.50) mg/dL; (17.83 ± 14.94) and (25.60 ± 13.29) mL/min; (143.50 ± 9.49)/(86.14 ± 7.38) and (128.07 ± 16.16)/(75.71 ± 7.56) mm Hg; (3.39 ± 1.57) and (2.00 ± 1.04) m/s; and (0.51 ± 0.10) and (0.61 ± 0.10); all showed statistical significance. Receiver operating characteristic analysis showed an area under curve of 0.8616 for PSV and 0.8535 for RI-ISA in diagnosing TRAS. Patients with TRAS in our center showed a unique characteristic of early onset. The most prominent clinical symptom of TRAS is increasing Scr level instead of refractory hypertension. Screening of color Doppler flow imaging with a graft artery PSV >2.5 m/s and RI-ISA <0.5 could yield a preliminary diagnosis of TRAS. Percutaneous transluminal angioplasty/stenting could effectively improve allograft function as well as color Doppler flow imaging indexes.

CXCL16 is activated by p-JNK and is involved in H2O2-induced HK-2 cell injury via p-ERK signaling

Acute kidney injury (AKI) leads to an abrupt deterioration of renal function. CXC chemokine ligand 16 (CXCL16) is a CXC-soluble chemokine and a cell surface scavenger receptor that is involved in tissue injury and inflammation. It is induced in AKI patients, but the molecular mechanism remains unclear. In this study, we have worked to determine the function of CXCL16 and to investigate the involvement of ERK and JNK signaling in AKI. We used H₂O₂ and recombinant human CXCL16 protein (rh CXCL16) to treat the human renal tubular epithelial cell line, HK-2, in vitro. The present results indicate that H₂O₂ inhibits proliferation, induces apoptosis, and up-regulates expression of CXCL16 and the CXCL16 receptor, CXCR6, in HK-2 cells. Furthermore, H₂O₂-induced proliferation inhibition, apoptosis, and inflammation in HK-2 cells were ameliorated by NAC (N-acetyl cysteine, the ROS scavenger) and SP600125 (the JNK inhibitor). The expression levels of CXCL16 and CXCR6 were also positively correlated with the phosphorylation level of JNK (p-JNK). Additionally, rh CXCL16 treatment led to effects like those of H₂O₂ treatment in HK-2 cells, with symptoms being effectively improved by CXCR6 siRNA and the ERK inhibitor (PD98059). In addition, rh CXCL16-induced HK-2 cell apoptosis, inflammation, and collagen deposition were lessened by CXCR6 siRNA and PD98059 treatment. In summary, the present results have indicated that CXCL16 is involved in H₂O₂-induced HK-2 cell injury, that CXCL16 is activated by p-JNK, and that the regulatory function of CXCL16 is involved in the phosphorylation of ERK.

Sites of gastrointestinal lesion induced by mycophenolate mofetil: a comparison with enteric-coated mycophenolate sodium in rats

Background

Immunosuppressant drugs for renal transplant mycophenolate mofetil (MMF) and enteric-coated mycophenolate sodium (EC-MPS) cause gastrointestinal (GI) disorders. The specific site of GI tract targeted by MMF and EC-MPS remains unclear.

Methods

In this study, we investigated the effects of MMF and EC-MPS on stomach, duodenum, jejunum, ileum, colon and rectum using a rat model. Rats were randomized into five groups: control, MMF (100 mg/kg·d), mofetil (30 mg/kg·d), EC-MPS (72 mg/Kg·d), mofetil + EC-MPS. Each group was treated with drugs once a day for 7 days through intra-gastric gavage. Diarrhea grade of each rat were measured every day, as well as the body weight. Blood was collected by tail nick and Seven days later, the rats were sacrificed, GI tissues were collected for Histological research.

Results

The results showed that diarrhea grade and weight loss were significantly higher in MMF group than other groups. The pathological score of MMF group was significantly higher than EC-MPS group and EC-MPS + mofetil group in jejunum and ileum tissues, but not other segments of GI tract. Absorption of EC-MPS is delayed, compared to that of MMF. MPAG concentration in duodenum, jejunum and ileum tissues of MMF group is higher than EC-MPS group. Mofetil may increase the magnitude of MPA absorption.

Conclusions

Our data suggested that MMF might target jejunum and ileum and induce GI injury. EC-MPS causes less injury in GI tract than MMF, probably due to its kinetic property.

Transplantation of Telocytes Attenuates Unilateral Ureter Obstruction-Induced Renal Fibrosis in Rats

BACKGROUND/AIMS

Previous studies imply that telocytes may have a protective effect on fibrosis in various organs, including the liver, colon, and heart. The effect of telocytes on renal fibrosis remains unknown. Herein, this study was designed to investigate the effect of telocytes on renal fibrosis and the potential mechanisms involved.

METHODS

In a unilateral ureteral obstruction (UUO)-induced renal fibrosis model, telocytes were injected via the tail vein every other day for 10 days. The degree of renal damage and fibrosis was determined using histological assessment. The expression of collagen I, fibronectin, epithelial-mesenchymal transition markers, and Smad2/3 phosphorylation was examined by western blot analyses. Real-time PCR and enzyme-linked immunosorbent assay were performed in vivo to detect the levels of transforming growth factor (TGF)-β1 and various growth factors.

RESULTS

Telocytes attenuated renal fibrosis, as evidenced by reduced interstitial collagen accumulation, decreased expression of fibronectin and collagen I, upregulation of E-cadherin, and downregulation of α-smooth muscle actin. Furthermore, telocytes decreased serum TGF-β1 levels, suppressed Smad2/3 phosphorylation, and increased the expression of hepatocyte growth factor (HGF) in rat kidney tissue following UUO. Blockage of HGF counteracted the protective effect of telocytes on UUO-treated kidneys. Through the detection of HGF mRNA levels in vitro, we found that telocytes had no effect on HGF expression compared with renal fibroblasts.

CONCLUSION

Telocytes attenuated UUO-induced renal fibrosis in rats, likely through enhancing the expression of HGF in an indirect manner.

Myeloid-derived suppressor cells in transplantation: the dawn of cell therapy

Myeloid-derived suppressor cells (MDSCs) are a series of innate cells that play a significant role in inhibiting T cell-related responses. This heterogeneous population of immature cells is involved in tumor immunity. Recently, the function and importance of MDSCs in transplantation have garnered the attention of scientists and have become an important focus of transplantation immunology research because MDSCs play a key role in establishing immune tolerance in transplantation. In this review, we summarize recent studies of MDSCs in different types of transplantation. We also focus on the influence of immunosuppressive drugs on MDSCs as well as future obstacles and research directions in this field.

Gene Therapy in Kidney Transplantation: Evidence of Efficacy and Future Directions

Allograft loss remains a severe clinical problem after kidney transplantation. The molecular mechanism of graft loss is a complex process involving T and/or B cell activation, inflammation responses, autophagy and apoptosis. Since these pathways are involved in immune responses in kidney transplant rejection, application of genetic interference to inhibit specific pathways could present an effective targeted gene therapy method. Recent studies have successfully attempted to use gene therapy to target the key molecules involved in immune responses during transplantation. This strategy has the potential to silence target genes associated with a variety of diseases, including those that trigger allograft loss following organ transplantation. In this review, we have discussed evidence of the clinical applicability of gene therapy in kidney transplantation based on known associations between kidney diseases and genes participating in the underlying mechanisms. The molecules contributing to immune responses and inflammatory injury are further highlighted as potential targets in future clinical therapy for renal transplantation.

Effect of different luteal support schemes on clinical outcome in frozen-thawed embryos transfer cycles

OBJECTIVE

To evaluate the clinical outcome of frozen-thawed embryo transfer (FET) when using different luteal support schemes.

STUDY DESIGN

Retrospective analysis of FET cycles was performed from June 2013 and December 2013. Infertile women, who underwent FET cycles utilizing embryos cryopreserved on day 3 post-insemination following an initial fresh IVF cycle. Patients were divided into three groups according to the luteal support scheme. Grade A (oral administration of progesterone, n=156), Group B (vaginal administration of progesterone, n=345), Group C (dissolved progesterone in oil with intramuscular infection, n=885), and group C was divided into two subgroups according to with (subgroup Cl, n=521) or without (subgroup C2 ,n=364) human chorionic gonadotrophi (hCG) injected intramuscularly. The authors compared patients' characteristics and the pregnancy outcomes of each group.

RESULTS

There was no difference in the patient characteristics of each group. There was no difference in the implantation rate or clinical and ongoing pregnancy rate among oral, vaginal, and intramuscular progesterone groups. The abortion and ectopic pregnancy rates were not significantly different among the three groups.

CONCLUSION

Oral progesterone in the FET cycles is convenient and has similar pregnancy outcomes compared with intramuscular or vaginal administration.

[Bone marrow mesenchymal stem cell-derived exosome protects kidney against ischemia reperfusion injury in rats]

OBJECTIVE

To explore the protective effects and mechanism of exosomes derived from bone marrow mesenchymal stem cells (BM-MSC) on ischemia reperfusion injury (IRI) in rats.

METHODS

Rat-MSC were isolated, cultured and identified.Exosome was extracted from BM-MSC and observed under transmission electron microscope (TEM). The expression of surface molecular marker CD63 was tested by flow cytometry. Male Sprague-Dawley rats were randomly grouped into sham-operated (Sham), ischemia reperfusion (IR), MSC-treated (IR+MSC), MSC-derived exosome-treated (IR+MSC-ex) and fibroblast-derived exosome-treated (IR+F-ex) groups. The model for ischemia reperfusion injury was constructed. The serum levels of creatinine and blood urea nitrogen (BUN) were tested in each group. The histomorphological changes in of renal tissue samples were examined by hematoxylin and eosin-stained tissue samples. Cellular apoptosis was examined by terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) staining. The expression levels of proinflammatory cytokines interleukin 1β and tumor necrosis factor α were examined by reverse transcription (RT)-PCR. And the expression level of caspase-3 was examined by Western blot.

RESULTS

Rat BM-MSCs were successfully isolated and cultured. Dectection of surface markers revealed high expression levels of CD29 and CD44 and a low expression level of CD34. MSC differentiated successfully into osteoblasts and lipocytes after growing in osteoblast- and lipocyte-inducing media respectively. Typical appearances of exosome were observed under transmission electron microscope. CD63 was positive on flow cytometry. Compared with the IR group, the IR+MSC and IR+MSC-ex groups showed low levels of serum creatinine and BUN, mild pathological injury, decreased number of apoptotic cells and low expression of inflammatory factors and caspase-3 (IR group, 4 310 ± 616;IR+MSC group, 2 569 ± 530; IR+MSC-ex group, 3 144 ± 343, both P < 0.05).

CONCLUSION

Rat BM-MSC-derived exosome protects against ischemia reperfusion injury with decreased inflammatory response and apoptosis in rats.

CO₂ sorption kinetics of scaled-up polyethylenimine-functionalized mesoporous silica sorbent

Two CO2 solid sorbents based on polyethylenimine, PEI (M(n) ∼ 423 and 10K), impregnated into mesoporous silica (MPS) foam prepared in kilogram quantities via a scale-up process were synthesized and systematically characterized by a range of analytical and surface techniques. The mesoporous silica sorbent impregnated with lower molecular weight PEI, PEI-423/MPS, showed higher capacity toward CO2 sorption than the sorbent functionalized with the higher molecular weight PEI (PEI-10K/MPS). On the other hand, PEI-10K/MPS exhibited higher thermal stability than PEI-423/MPS. The kinetics of CO2 adsorption on both PEI/MPS fitted well with a double-exponential model. According to this model CO2 adsorption can be divided into two steps: the first is fast and is attributed to CO2 adsorption on the sorbent surface; the second is slower and can be related to the diffusion of CO2 within and between the mesoporous particles. In contrast, the desorption process obeyed first-order kinetics with activation energies of 64.3 and 140.7 kJ mol(-1) for PEI-423/MPS and PEI-10K/MPS, respectively. These studies suggest that the selection of amine is critical as it affects not only sorbent capacity and stability but also the energy penalty associated with sorbent regeneration.

Bio-inspired laminated graphite nanosheets/copper composites

Bio-inspired laminated graphite nanosheets/copper composites with modified mechanical properties.

Dynamic change of glomerular filtration rate in the early stage is associated with kidney allograft status: a preliminary report

Background

This study aimed to investigate the relationship between the dynamic changes of estimated glomerular filtration rate (eGFR) in the early stage post renal transplantation and renal allograft dysfunction.

Methods

We selected 9 patients with interstitial fibrosis and tubular atrophy (IF/TA) and 11 patients with stable renal function based on the Banff 2007 classification system. Pathology of the patients was evidenced with renal biopsy results. Glomerular filtration rate (GFR) was calculated continuously for 14 days post-transplantation by using an estimated GFR (eGFR) formula adjusted into Chinese. Linear regression was employed, and eGFR slopes were compared. Prisoners or organs from prisoners were not used in this study.

Results and Conclusion

The eGFR slope in the IF/TA group was significantly higher than that in the stable group (P < 0.01), and a cut-off value of 5.11 mL/min/1.73 m²/d was a reliable clinical value in a receiver operating characteristic (ROC) curve. On the basis of the ROC area under the curve, predictive accuracy of the eGFR slope was excellent (0.848). In conclusion, the eGFR in IF/TA increased faster within a period of 14 days post-transplantation, suggesting that reperfusion in the early stage may damage the glomerular filtration membrane to some extent. Furthermore, reperfusion might adversely affect long-term renal allograft survival.

Enhanced performance configuration for fast-switching deformed helix ferroelectric liquid crystal continuous tunable Lyot filter

In this paper, we present a novel design configuration of double DHFLC wave plate continuous tunable Lyot filter, which exhibits a rapid response time of 185 μs, while the high-contrast ratio between the passband and stop band is maintained throughout a wide tunable range. A DHFLC tunable filter with a high-contrast ratio is attractive for realizing high-speed optical processing devices, such as multispectral and hyperspectral imaging systems, real-time remote sensing, field sequential color display, and wavelength demultiplexing in the metro network. In this work, an experimental prototype for a single-stage DHFLC Lyot filter of this design has been fabricated using photoalignment technology. We have demonstrated that the filter has a continuous tunable range of 30 nm for a blue wavelength, 45 nm for a green wavelength, and more than 50 nm for a red wavelength when the applied voltage gradually increases from 0 to 8 V. Within this tunable range, the contrast ratio of the proposed double wave plate configuration is maintained above 20 with small deviation in the transmittance level. Simulation and experimental results showed the proposed double DHFLC wave plate configuration enhances the contrast ratio of the tunable filter and, thus, increases the tunable range of the filter when compared with the Lyot filter using a single DHFLC wave plate. Moreover, we have proposed a polarization insensitive configuration for which the efficiency of the existing prototype can theoretically be doubled by the use of polarization beam splitters.

Renal telocytes contribute to the repair of ischemically injured renal tubules

Telocytes (TCs), a distinct type of interstitial cells, have been identified in many organs via electron microscopy. However, their precise function in organ regeneration remains unknown. This study investigated the paracrine effect of renal TCs on renal tubular epithelial cells (TECs) in vitro, the regenerative function of renal TCs in renal tubules after ischaemia–reperfusion injury (IRI) in vivo and the possible mechanisms involved. In a renal IRI model, transplantation of renal TCs was found to decrease serum creatinine and blood urea nitrogen (BUN) levels, while renal fibroblasts exerted no such effect. The results of histological injury assessments and the expression levels of cleaved caspase-3 were consistent with a change in kidney function. Our data suggest that the protective effect of TCs against IRI occurs via inflammation-independent mechanisms in vivo. Furthermore, we found that renal TCs could not directly promote the proliferation and anti-apoptosis properties of TECs in vitro. TCs did not display any advantage in paracrine growth factor secretion in vitro compared with renal fibroblasts. These data indicate that renal TCs protect against renal IRI via an inflammation-independent pathway and that growth factors play a significant role in this mechanism. Renal TCs may protect TECs in certain microenvironments while interacting with other cells.

Telocytes in the human kidney cortex

Renal interstitial cells play an important role in the physiology and pathology of the kidneys. As a novel type of interstitial cell, telocytes (TCs) have been described in various tissues and organs, including the heart, lung, skeletal muscle, urinary tract, etc. (www.telocytes.com). However, it is not known if TCs are present in the kidney interstitium. We demonstrated the presence of TCs in human kidney cortex interstitium using primary cell culture, transmission electron microscopy (TEM) and in situ immunohistochemistry (IHC). Renal TCs were positive for CD34, CD117 and vimentin. They were localized in the kidney cortex interstitial compartment, partially covering the tubules and vascular walls. Morphologically, renal TCs resemble TCs described in other organs, with very long telopodes (Tps) composed of thin segments (podomers) and dilated segments (podoms). However, their possible roles (beyond intercellular signalling) as well as their specific phenotype in the kidney remain to be established.

The protective effect of baicalin against renal ischemia-reperfusion injury through inhibition of inflammation and apoptosis

Background

Renal ischemia-reperfusion injury (IRI) increases the rates of acute kidney failure, delayed graft function, and early mortality after kidney transplantation. The pathophysiology involved includes oxidative stress, mitochondrial dysfunction, and immune-mediated injury. The anti-oxidation, anti-apoptosis, and anti-inflammation properties of baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis, have been verified. This study therefore assessed the effects of baicalin against renal IRI in rats.

Methods

Baicalin was intraperitoneally injected 30 min before renal ischemia. Serum and kidneys were harvested 24 h after reperfusion. Renal function and histological changes were assessed. Markers of oxidative stress, the Toll-like receptor (TLR)2 and TLR4 signaling pathway, mitochondrial stress, and cell apoptosis were also evaluated.

Results

Baicalin treatment decreased oxidative stress and histological injury, and improved kidney function, as well as inhibiting proinflammatory responses and tubular apoptosis. Baicalin pretreatment also reduced the expression of TLR2, TLR4, MyD88, p-NF-κB, and p-IκB proteins, as well as decreasing caspase-3 activity and increasing the Bcl-2/Bax ratio.

Conclusions

Baicalin may attenuate renal ischemia-reperfusion injury by inhibiting proinflammatory responses and mitochondria-mediated apoptosis. These effects are associated with the TLR2/4 signaling pathway and mitochondrial stress.

Combination of Total Lymphoid Irradiation, Low-Dose IVIG and ATG as Rescue Therapy for Highly Sensitized and Antibody-Mediated Rejection Renal Transplant Recipients

Background: It is now clear that antibody- mediated rejection (AMR) is a major cause of graft failure. To avoid AMR, transplantation is preferably performed in non- or low-sensitized patients. For patients with pre-existing HLA antibodies due to pre-transplant sensitization or those with de novo HLA antibodies due to transplantation, elimination or reduction of HLA antibodies becomes critical to prevent AMR. Materials and Methods: In this clinical trial, we test the efficacy of a combination therapy of total lymphoid irradiation (TLI), low- dose intravenous immunoglobulin (IVIG), and anti-thymocyte globulin (ATG) with or without plasmapheresis (PP) in treating patients with HLA antibodies. Thirteen HLA antibody positive patients receiving renal transplants during 2009-2011 were enrolled in this study. Two cases with pre-existing HLA antibodies received combined therapy of TLI, PP, low-dose IVIG, and ATG induction. Eleven cases with de novo HLA antibodies and biopsy-proven AMR received TLI, low-dose IVIG, and ATG with or without PP.

RESULTS

Two sensitized patients with pre-existing HLA antibodies were successfully desensitized and able to accept renal transplantation without an observable AMR episode in 12 months of post-transplant follow-up. In 11 AMR cases with de novo HLA antibodies, only one patient failed to respond to the therapy and lost the allograft. In the other ten cases, the follow-up biopsies at one year post transplant showed no evidence of rejection and the patients had stable renal function. B cell proliferation was persistently inhibited in both desensitization and AMR patients.

CONCLUSIONS

Combined therapy of TLI, PP, low-dose IVIG, and ATG is an effective therapeutic measure to reduce the level of HLA antibodies and therefore to desensitize recipients pre-transplant and to reverse AMR post transplant. The potential mechanism of the therapy involves inhibition of B cell proliferation.

Hematopoietic stem cell transplantation induces immunologic tolerance in renal transplant patients via modulation of inflammatory and repair processes

Background

Inducing donor-specific tolerance in renal transplant patients could potentially prevent allograft rejection and calcineurin inhibitor nephrotoxicity. Combined kidney and hematopoietic stem cell transplant from an HLA-matched donor is an exploratory and promising therapy to induce immune tolerance. Investigtion of molecular mechanisms involved in the disease is needed to understand the potential process of cell therapy and develop strategies to prevent this immunologic rejection.

Methods

We enrolled nine patients in a clinical study in which cryopreserved donor hematopoietic stem cells were infused on days 2, 4, and 6 after kidney transplantation. One month post-transplant, 4 plasma samples were collected from combined transplants (C + Tx), and 8 plasma samples from patients with kidney transplantation alone (Tx). High abundance proteins in plasma were depleted and the two-dimensional liquid chromatography-tandem mass spectrometry coupled with iTRAQ labeling was utilized to identify the protein profiling between the two groups. Clusters of up- and down-regulated protein profiles were submitted to MetaCore for the construction of transcriptional factors and regulation networks.

Results and Discussion

Among the 179 identified proteins, 65 proteins were found in C + Tx with at least a 2-fold change as compared with Tx. A subset of proteins related to the complement and coagulation cascade, including complement C3a,complement C5a, precrusors to fibrinogen alpha and beta chains,was significantly downregulated in C + Tx. Meanwhile, Apolipoprotein-A1(ApoA1), ApoC1, ApoA2, ApoE, and ApoB were significantly lower in Tx compared to C + Tx. Gene ontology analysis showed that the dominant processes of differentially expressed proteins were associated with the inflammatory response and positive regulation of plasma lipoprotein particle remodeling.

Conclusions

Thus, our study provides new insight into the molecular events in the hematopoietic stem cell-induced immunologic tolerance.

Proinflammatory protein CARD9 is essential for infiltration of monocytic fibroblast precursors and cardiac fibrosis caused by Angiotensin II infusion

Background

Angiotensin II (Ang II)–induced cardiac remodeling with the underlying mechanisms involving inflammation and fibrosis has been well documented. Cytosolic adaptor caspase recruitment domain 9 (CARD9) has been implicated in the innate immune response. We aimed to examine the role of CARD9 in inflammation and cardiac fibrosis induced by Ang II.

Methods

Two-month-old CARD9-deficient (CARD9^−/−) and wild-type (WT) male mice were infused with Ang II (1,500 ng/kg/min) or saline for 7 days. Heart sections were stained with hematoxylin and eosin and Masson trichrome and examined by immunohistochemistry; and activity and protein levels were measured in macrophages obtained from mice.

Results

WT mice with Ang II infusion showed a marked increase in CARD9⁺ macrophages in the heart, but CARD9^−/− mice showed significantly suppressed macrophage infiltration and expression of proinflammatory cytokines, including interleukin-1β (IL-1β) and connective tissue growth factor (CTGF). Importantly, Ang II–induced cardiac fibrosis (extracellular matrix and collagen I deposition) was diminished in CARD9^−/− hearts, as was the expression of transforming growth factor-β (TGF-β) and level of myofibroblasts positive for α-smooth muscle actin (α-SMA). Furthermore, Ang II activation of nuclear factor-κB (NF-κB), JNK and p38 mitogen-activated protein kinases (MAPKs) in WT macrophages was reduced in CARD9^−/− macrophages.

Conclusion

CARD9 plays an important role in regulating cardiac inflammation and fibrosis in response to elevated Ang II.

An optimised, small-scale preparation of high-quality RNA from dry seeds of Davidia involucrata

INTRODUCTION

The dormancy of Davidia involucrata seeds normally lasts for an extended period of time and because of this unique property the species is an excellent model for studying the molecular mechanisms of plant dormancy. The use of minimal plant material is desirable for RNA extraction since D. involucrata is a rare plant and it is relatively difficult to collect large amounts of seeds in order to perform molecular biology studies.

OBJECTIVE

To improve the quality of RNA obtained from seeds of D. involucrata by eliminating the oxidation of polyphenols during extraction and by preventing polysaccharides and other impurities from being extracted.

METHODS

A previously described method was modified by the addition of 4% (w/v) poly(N-vinyl-2-pyrrolidone) to the dry seeds during grinding and by adding 5% (v/v) beta-mercaptoethanol and 28% (v/v) ethanol to the extraction buffer. Two further centrifugation steps (5000 and 8000 rpm) were utilised and one-seventh volume of ethanol was incubated with the supernatant at 4 degrees C for 2-3 h prior to the precipitation of RNA.

RESULTS

Following these modifications, an effective method was established for total RNA extraction from a small amount of dry seeds of D. involucrata. The isolated RNA was shown to have high purity and integrity by gel electrophoresis and spectrophotometry, and was confirmed to be suitable for RT-PCR and the construction of cDNA libraries.

CONCLUSION

The modified method reduced the amount of seeds required for extraction of total DNA and was beneficial for preserving the endangered species.

Bacterial virus phi29 pRNA as a hammerhead ribozyme escort to destroy hepatitis B virus

The DNA-packaging pRNA of bacterial virus phi29, which forms dimers and then hexamers, contains two independent tightly self-folded domains. Circularly permuted pRNAs were constructed without impacting pRNA folding. Connecting the pRNA 5'/3' ends with variable sequences did not disturb its folding and function. These unique features, which help prevent two common problems - exonuclease degradation and misfolding in the cell, make pRNA an ideal vector to carry therapeutic RNAs. A pRNA-based vector was designed to carry hammerhead ribozymes that cleave the hepatitis B virus (HBV) polyA signal. The chimeric HBV-targeting ribozyme was connected to the pRNA 5'/3' ends as circularly permuted pRNA. Two cis-cleaving ribozymes were used to flank and process the chimeric ribozyme. The hammerhead ribozyme including its two arms for HBV targeting was able to fold correctly while escorted by the pRNA. The chimeric ribozyme cleaved the polyA signal of HBV mRNA in vitro almost completely. Cell culture studies showed that the chimeric ribozyme was able to enhance the inhibition of HBV replication when compared with the ribozyme not escorted by pRNA, as demonstrated by Northern blot and e-antigen assays. pRNA could also carry another hammerhead ribozyme to cleave other RNA substrate. These findings suggest that pRNA can be used as a vector for imparting stability to ribozymes, antisense, and other therapeutic RNA molecules in vivo.

On modelling the kinestatic charge detector for digital radiographic diagnostic and portal imaging

The kinestatic charge detection (KCD) principle has been a digital radiography technique for more than a decade. The advances of the KCD technique have gone from diagnostic imaging to portal imaging. However, little work has been done on understanding the selection of key KCD parameters and relationships between them. In the present study, an engineering model was established that could be used to optimize the placements of key parameters in terms of KCD system mechanical design. In the proposed KCD engineering model, the basic energy conservation law was applied to the process of ion transmission. It allows for the computation of the KCD design parameters such as the optimum grid placement, high voltage board tilt angle and grid wire space, as well as to provide recommendations on high voltage board and electric potentials and their ratio.

[Activation of transcription factors and induction of cytokines from macrophages in chronic obstructive pulmonary disease]

OBJECTIVE

To investigate the activation of transcription factors and induction of cytokines from alveolar macrophages in chronic obstructive pulmonary disease (COPD).

METHODS

Alveolar macrophages were collected by fibrobronchoscopy from 8 patients with chronic bronchitis, 8 patients with COPD, and 8 healthy volunteers. All patients were at stable stage. The macrophages thus collected were cultured and stimulated with lipopolysaccharide (LPS, 10 micrograms/ml). The IL-8, IL-1 beta, TNF alpha and IL-6 thus produced were measured by ELISA in the supernatant. Nuclear factor-kappa B (NF kappa B), activator protein-1 (AP-1), AP-2 and AP-3 were detected by electrophoretic mobility shift assay.

RESULTS

The concentration of IL-8 released from macrophages of patients with COPD at stable stage before LPS stimulation was about 3 times higher than that in the healthy control (F = 4.34, P < 0.05). The concentration of IL-8 released from macrophages in patients with COPD was increased further after LPS stimulation in comparison to that in healthy controls(F = 3.56, P < 0.05). The concentration of IL-1 beta and that of TNF alpha released from macrophages of COPD patients were further increased after LPS stimulation (P < 0.05) in the COPD patients, but there was no difference in the concentration of IL-1 beta and between the control and COPD patients before LPS stimulation. The constitutive activity of AP-1 and the activity of NF kappa B induced by LPS were higher in the patients with COPD than in the controls.

CONCLUSION

The alverlar macrophages of patients with COPD at stable stage may release higher concentration of IL-8 and IL-1 beta. LPS stimulation increases the release of IL-1 beta and TNF alpha of alveolar macrophages. Enhancement of activity of NF kappa B and AP-1 may positively regulate the production of IL-8 and IL-1 beta in the airflow obstruction.

Protective effect of gypenosides on DNA and RNA of rat neurons in cerebral ischemia-reperfusion injury

AIM

To observe the protective effect of gypenosides (GP) on the neurons of hippocampus, cerebral cortex, corpus striatum, and dentate gyrus in cerebral ischemia-reperfusion injury of rats.

METHODS

Modified 4-vessel occlusion (4-VO) method was used to establish the model of acute global ischemia. The acridine orange (AO) staining method was used to observe the DNA and RNA contents of cerebral ischemia-reperfusion injury model in the areas.

RESULTS

The fluorescent intensity (reflecting DNA and RNA contents) of the DNA and RNA in the areas of cerebral ischemia-reperfusion injury was markedly abated compared with the normal control group. In the group of ig GP (100 mg/kg) it was enhanced compared with the model group and was the same as the normal control group.

CONCLUSION

The injury of the DNA and RNA in the areas of ischemia-reperfusion model was decreased by GP.