Rhodobacter sphaeroides as a model to study the ecotoxicity of 1-alkyl-3-methylimidazolium bromide.

The purple non-sulfur bacterium Rhodobacter sphaeroides was selected as a biological model to investigate its response to the toxicity of 1-alkyl-3-methylimidazolium bromide ([Cnmim]Br), a type of ionic liquid (IL), with different alkyl chain lengths (n describes the number of carbon atoms in the alkyl chain). The inhibition of bacterial growth by [Cnmim]Br was positively correlated with n. Morphological characterization revealed that [Cnmim]Br caused cell membrane perforation. The signal amplitude of the electrochromic absorption band shift of endogenous carotenoids showed a negatively linear correlation with n, and the amplitude of the blue-shift of the B850 band in light-harvesting complex 2 showed a positively linear correlation with n. Furthermore, an increase in blocked ATP synthesis and increase in antioxidant enzyme activity were observed in chromatophores treated with ILs containing longer alkyl chains. In summary, the purple bacterium can be developed as a model to monitor ecotoxicity and examine the mechanism of IL toxicity.

A modified regimen of extracorporeal cardiac shock wave therapy for treatment of coronary artery disease.

BACKGROUND: Cardiac shock wave therapy (CSWT) improves cardiac function in patients with severe coronary artery disease (CAD). We aimed to evaluate the clinical outcomes of a new CSWT treatment regimen. METHODS: The 55 patients with severe CAD were randomly divided into 3 treatment groups. The control group (n = 14) received only medical therapy. In group A ( n = 20), CSWT was performed 3 times within 3 months. In group B ( n = 21), patients underwent 3 CSWT sessions/week, and 9 treatment sessions were completed within 1 month. Primary outcome measurement was 6-minute walk test (6MWT). Other measurements were also evaluated. RESULTS: The 6MWT, CCS grading of angina, dosage of nitroglycerin, NYHA classification, and SAQ scores were improved in group A and B compared to control group. CONCLUSIONS: A CSWT protocol with 1 month treatment duration showed similar therapeutic efficacy compared to a protocol of 3 months duration. CLINICAL TRIAL REGISTRY: We have registered on ClinicalTrials.gov, the protocol ID is CSWT IN CHINA.

Diazoxide attenuates ischemia/reperfusion injury via upregulation of heme oxygenase-1 after liver transplantation in rats.

AIM: To evaluate the effects of diazoxide on ischemia/reperfusion (I/R)-injured hepatocytes and further elucidate its underlying mechanisms. METHODS: Male Sprague-Dawley rats were randomized (8 for donor and recipient per group) into five groups: I/R group (4 h of liver cold ischemia followed by 6 h of reperfusion); heme oxygenase-1 (HO-1) small interfering RNA (siRNA) group (injection of siRNA via donor portal vein 48 h prior to harvest); diazoxide (DZ) group (injection of DZ via donor portal vein 10 min prior to harvest); HO-1 siRNA + DZ group; and siRNA control group. Blood and liver samples were collected at 6 h after reperfusion. The mRNA expressions and protein levels of HO-1 were determined by reverse transcription polymerase chain reaction and Western blotting, and tissue morphology was examined by light and transmission electron microscopy. Serum transaminases level and cytokines concentration were also measured. RESULTS: We observed that a significant reduction of HO-1 mRNA and protein levels in HO-1 siRNA and HO-1 siRNA + DZ group when compared with I/R group, while the increases were prominent in the DZ group. Light and transmission electron microscopy indicated severe disruption of tissue with lobular distortion and mitochondrial cristae damage in the HO-1 siRNA and HO-1 siRNA + DZ groups compared with DZ group. Serum alanine aminotransferase, aspartate transaminase, tumor necrosis factor-α and interleukin-6 levels increased in the HO-1 siRNA and HO-1 siRNA + DZ groups, and decreased in the DZ group. CONCLUSION: The protective effect of DZ may be induced by upregulation of HO-1. By inhibiting expression of HO-1, this protection pretreated with DZ was abolished.

A novel chemosensor based on rhodamine derivative for colorimetric and fluorometric detection of Cu2+ in aqueous solution.

A new rhodamine-based reversible chemosensor (2) was synthesized, which exhibits high sensitivity and selectivity for Cu(2+) but no significant response toward other competitive metal ions in aqueous solution. Upon the addition of Cu(2+), the spirolactam ring of 2 was opened and the solution color changed from colorless to red. Strangely, an unexpected fluorescence quenching was observed, which is contrary to the fluorescence turn-on of the most rhodamine-based chemosensors. The likely novel sensing mechanism has been proposed.

Roles of Kupffer cells in liver transplantation.

Kupffer cells, the resident macrophages of the liver, not only exert phagocytosis but also excrete proinflammatory cytokines. Large amounts of cytokines, produced by activated Kupffer cells, can induce aggravate liver ischemia/reperfusion (I/R) injury. Also, Kupffer cells that express protective genes protect from I/R injury after liver transplantation. Due to their key location, Kupffer cells might function as antigen-presenting cells and participate in transplantation immunity. They also seem to play a key role in innate immune responses and host defence through the expression and secretion of soluble inflammatory mediators. With this review we want to assist in improving the understanding of the contribution of Kupffer cells in liver I/R injury and the development of the transplantation immune. We hope that the delineation of the complex mechanisms of dysregulation may inspire the design and development of novel treatment approaches.

[Effects of CDH1 gene promoter methylation on expression of E-cadherin and beta-catenin and its clinicopathological significance in colon carcinoma].

OBJECTIVE: To investigate the relationship between methylation of the CDH1 gene promoter on the expression of E-cadherin and ß-catenin, and to evaluate the correlation with clinicopathological characteristics of the colonic carcinoma. METHODS: Methylation specific PCR (MSP) was used to detect CDH1 gene promoter methylation in the cancer tissue, adjacent tissues and normal tissues in 68 patients. The expression of E-cadherin and ß-catenin was determined by immunohistochemistry staining. RESULTS: The positive rate of CDH1 gene promoter methylation was 32.4% in adjacent tissues and 57.4% in cancer tissue, while no detectable methylation was found in all the normal tissues. The difference was statistically significant. The positive rate of E-cadherin was 92.6% in the normal tissues, 66.2% in the adjacent tissues and 44.1% in the cancer tissues. In all normal tissues, ß-catenin was expressed only at the cellular membrane but not in the cytosol or nucleus, while the expression of ß-catenin was present in the cytosol or nucleus in 29.4% of the adjacent tissues and 50.0% of the cancer tissues. The positive rate of CDH1 gene promoter methylation was negatively correlated with E-cadherin expression(r=-0.312, P=0.01) and positively correlated with ß-catenin cytosolic/nucleus expression(r=0.309, P=0.018). The differentiation and metastasis of colonic carcinoma were associated with the aberrant expression of E-cadherin, ß-catenin, and methylation of CDH1 promoter (P<0.05). CONCLUSION: CDH1 gene promoter methylation may lead to aberrant expression of E-cadherin and ß-catenin in colonic carcinoma, and may play an important role in promoting the invasion of tumor.

Rapid identification of mtDNA somatic mutations in gastric cancer tissues based on the mtDNA phylogeny.

Mitochondrial DNA (mtDNA) somatic mutations have been identified in nearly all kinds of cancer during the past decade. Normally one need to determine the complete mtDNA sequences from both cancerous and normal tissues of the same patient to score the somatic mutation in cancer. In this study, we intended to explore a strategy to quickly identify somatic mutations in the entire mtDNA genome based on its phylogeny. The principal assumption for this strategy is that somatic mutations, as recently accumulated in cancerous tissue, have younger age and will be located in the terminal branches of mtDNA phylogenetic tree. In contrast, the haplogroup-specific variants, which appear as germline variants and have ancient age, will be located in the basal or intermediate-node branches of the tree, depending on their relative age. When the complete mtDNA sequence of the cancerous tissue is determined and is classified relative to the available mtDNA phylogeny, we only need to screen the variants that are located in the terminal branch in the paracancerous tissue or other normal tissue from the same patient to identify somatic mutations in cancer. We validated this strategy by using paired gastric cancer tissue and paracancerous tissue or blood from 10 Chinese patients (including one with gastric stromal tumor). A total of seven somatic mutations were identified in the cancerous tissues from four patients. Our result suggests that employing mtDNA phylogenetic knowledge facilitates rapid identification of mitochondrial genome somatic mutations in cancer.

Postconditioning prevents ischemia/reperfusion injury in rat liver transplantation.

BACKGROUND/AIMS: Ischemic postconditioning (Postcon) is a phenomenon that intermittent interruptions of blood flow in the early phase of reperfusion can protect organ against ischemia/ reperfusion (I/R) injury. The potential application of postconditioning to liver is not available. In the present study, we investigated the effects of Postcon in liver I/R injury in rat liver transplantation models. METHODOLOGY: Adult male Sprague-Dawley rats were randomly allocated to three groups including sham group without I/R, I/R group with 24h cold ischemic donor liver before orthotopic liver transplantation, and Postcon group treated the same as I/R group and 6 cycles of 60s ischemia and 60s reperfusion at the onset of reperfusion. Peripheral blood samples were collected after reperfusion. Serum transaminases level, plasma cytokines concentration, histopathology, liver tissues malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were measured. The heme oxygenase-1 (HO-1) expression levels of liver were evaluated. RESULTS: Serum transaminases level and plasma cytokines concentration significantly decreased in Postcon group as compared to I/R group. Postcon treatment reduced MDA production and increased SOD activity compared with the I/R group. The HO-1 expression levels of liver were significantly higher in Postcon rats than in the I/R group at the end of reperfusion. CONCLUSIONS: These results indicate that Post-con ameliorates liver I/R injury. This protective effect is likely mediated by up-regulation of HO-1 expression.

[Extracorporeal cardiac shock wave therapy for treatment of coronary artery disease].

OBJECTIVE: To evaluate the feasibility and efficiency of extracorporeal cardiac shock wave therapy (CSWT) for treatment of coronary artery disease. METHODS: Twenty-five patients with 1 - 16 years history of chronic angina pectoris underwent the CSWT. Before and after the treatment, low-dose Dobutamine stress echocardiography and (99)Tc(m)-MIBI myocardial perfusion SPECT were applied to locate the ischemic segments, detect the viable myocardium and evaluate the effect of CSWT. Under the guidance of echocardiography, CSWT was applied in R-wave-triggered manner with low energy (0.09 mJ/mm(2)) at 200 shoots/spot for 9 spots (-1-0-+1 combination). Patients were divided group A and group B. Sixteen patients in group A were applied 9 sessions on 29 segments within 3 month and nine patients in group B were applied 9 sessions on 13 segments within 1 month. Ten chronic angina pectoris patients receiving standard medication served as controls. RESULTS: All patients completed the 9 sessions without procedural complications or adverse effects. CSWT significantly improved symptoms as evaluated by NYHA, Canadian Cardiovascular Society (CCS) class sores, Seattle angina questionnaire (SAQ), 6-min walk and the use of nitroglycerin (P < 0.05). CSWT also improved myocardial perfusion and regional myocardium function as evaluated by rest SPECT and stress peak systolic strain rate (PSSR) (P < 0.01). Myocardial perfusion improvement was more significant in group A compared with group B (1.21 ± 0.86 vs. 0.83 ± 0.80, P < 0.01). All parameters remained unchanged in control group during follow up. CONCLUSION: These preliminary results indicate that CSWT is safe and effective on ameliorating anginal symptoms for chronic angina pectoris patients.

Cardiac shock wave therapy reduces angina and improves myocardial function in patients with refractory coronary artery disease.

BACKGROUND: Safe and effective therapeutic management of refractory coronary artery disease (CAD) in heart patients is critical to enhance cardiovascular function and improve quality of life. Current therapies for refractory CAD are inadequate in ameliorating angina and promoting revascularization of ischemic myocardium. HYPOTHESIS: Cardiac shock wave therapy (CSWT) is a safe and effective noninvasive intervention in the management of patients with refractory CAD. METHODS: The study enrolled 9 male patients age 50 to 70 years (5.11 ± 5.46 years) with a diagnosis of CAD and stent implantation (3.00 ± 2.24 stents). CSWT was carried out for 3 months at 3 intervals during the first week of each month (first, third, and fifth day), for a total of 9 therapies per patient. Dobutamine stress echocardiography and radionuclide angiography identified the myocardial ischemic segments. The effects of CSWT on myocardial perfusion and systolic function were examined. Other outcome measures included myocardial injury enzyme markers, angina scale, nitroglycerin dosage, and cardiopulmonary fitness assessments. RESULTS: Improved myocardial blood flow and regional systolic function (stress peak systolic strain rate - 1.10 to - 1.60 s(-1), P = 0.002) were detected in patients following CSWT. Reductions in creatine kinase (87.89 ± 36.69 to 86.22 ± 35.96 IU/L, P = 0.046), creatine kinase MB (10.89 ± 5.73 to 10.11 ± 5.93 IU/L, P = 0.008), aspartate transaminase (interquartile range [IQR], 28.00 to 27.00 IU/L, P = 0.034) were also found. Angina (Canadian Cardiovascular Society scale IQR 3.0 to 2.0, P = 0.035) and nitroglycerin dose reduction (IQR 3.0 to 1.0 times/wk, P = 0.038) were reported. CONCLUSIONS: This study is a preliminary assessment of CSWT in patients with refractory CAD. We report that CSWT is a noninvasive, effective, and safe intervention in the treatment of refractory CAD.

Heme oxygenase-1 protects donor livers from ischemia/reperfusion injury: the role of Kupffer cells.

AIM: To examine whether heme oxygenase (HO)-1 overexpression would exert direct or indirect effects on Kupffer cells activation, which lead to aggravation of reperfusion injury. METHODS: Donors were pretreated with cobalt protoporphyrin (CoPP) or zinc protoporphyrin (ZnPP), HO-1 inducer and antagonist, respectively. Livers were stored at 4 degrees C for 24 h before transplantation. Kupffer cells were isolated and cultured for 6 h after liver reperfusion. RESULTS: Postoperatively, serum transaminases were significantly lower and associated with less liver injury when donors were pretreated with CoPP, as compared with the ZnPP group. Production of the cytokines tumor necrosis factor-alpha and interleukin-6 generated by Kupffer cells decreased in the CoPP group. The CD14 expression levels (RT-PCR/Western blots) of Kupffer cells from CoPP-pretreated liver grafts reduced. CONCLUSION: The study suggests that the potential utility of HO-1 overexpression in preventing ischemia/reperfusion injury results from inhibition of Kupffer cells activation.

[Synthesis and fluorescence properties of thermo-responsive microgel nanoparticles].

In the present paper, the preparation and properties of Eu(III) on poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AAc)) were described. At first, P(NIPAM-co-AAc) microgel nanoparticles were prepared by the precipitation copolymerization of N-isopropylacrylamide with acrylic acid in the presence of N, N-methylenebisacrylamide in water. The morphology and size of the P(NIPAM-co-AAc) nanoparticles were characterized by the scanning electron microscope (SEM) method. The result of SEM shows that the sample is uniformly sized spherical particle and the average particle size of the P(NIPAM-co-AAc) is about 365 nm. Then, EuCl3 was chosen to interact with P(NIPAM-co-AAc) nanoparticles and formed the complex of P(NIPAM-co-AAc)-Eu(III). The complex was characterized by Fourier transform infrared spectroscopy, ultraviolet-visible and fluorescence spectroscopy. It was found that the complex shows thermo-responsive fluorescence from the experimental results. There exists a energy transfer between the polymer ligand and the Eu(III), which can enhance fluorescence emission of the polymer ligand and Eu(III) at the same time. The LCST of P(NIPAM-co-AAc) containing Eu(III) has changed little after the formation of the complex of P(NIPAM-co-AAc)-Eu(III). Therefore, the complex can be used for developing the new applications in biomedical and fluorescence field.

A comparative study of gene vaccines encoding different extracellular domains of the vascular endothelial growth factor receptor 2 in the mouse model of colon adenocarcinoma CT-26.

AIMS: To compare the immunogenicity and anti-tumor effects of gene vaccines encoding domains 1-4 with full length of extracellular region of VEGFR2. RESULTS: Both DNA vaccines decreased VEGF levels and rose specific antibodies; the lymphocyte subsets of vaccinated mice maintained high; tumor latency period and survival time of immunized mice were prolonged; tumor size, weight, MVD and liver metastases were significantly less than the control groups. METHODS: Mouse model of CT-26 adenocarcinoma of colon were treated with orally immunized gene vaccine encoding extracellular 1-4 and full length of VEGFR2 respectively. The effect of anti-tumor was evaluated by detecting the tumor volume, mice survival time, intratumoral microvessel density (MVD) and liver metastases. To explore the reasonable mechanism of the oral gene vaccines, the levels of VEGF and anti-VEGFR2 antibody in serum were detected by ELISA, CD4+ and CD8+ T cells in peripheral blood and subcutaneous tumors were analyzed by flow cytometer and immunohischemistry respectively. CONCLUSION: Compared with full length of extracellular domain of VEGFR2, extracellular regions 1-4 of VEGFR2 has been sufficient to decrease the serum VEGF level and to inhibit tumor growth and metastasis specifically.

1-[(Diethyl-amino-carbon-yl)meth-yl]-2-[hydr-oxy(6-methoxy-quinolin-4-yl)meth-yl]-5-vinyl-1-azoniabicyclo-[2.2.2]octane chloride monohydrate.

In the title compound, C(26)H(36)N(3)O(3) (+)·Cl(-)·H(2)O, the mol-ecular structure of the cation is stabilized by a number of C-H⋯O intra-molecular inter-actions. In the crystal structure, O-H⋯Cl and C-H⋯Cl hydrogen bonds link the ions into a ribbon-like structure along the a axis.

(Z)-3-Anilino-1,3-diphenylprop-2-en-1-one.

In the title compound, C(21)H(17)NO, the phenyl ring directly linked to the carbonyl group is oriented at an angle of 7.3 (2)° with respect to the aniline ring, and at an angle of 55.6 (2)° with respect to the other phenyl ring. There is an intra-molecular hydrogen bond involving the NH group and the carbonyl O atom. The crystal structure is stabilized by weak C-H⋯π inter-actions, which link the mol-ecules into a herringbone arrangement.

[Study on spectroscopic properties of rare earth complexes with poly (N-vinylacetamide)].

Terbium-lanthanum (or gadolinium)-poly(N-vinylacetamide) complexes were synthesized and characterized by UV-Vis absorption spectroscopy, FTIR, XPS and fluorescence spectroscopy. The results of UV-Vis, FTIR and XPS suggested that terbium and lanthanum (or gadolinium) ions were bonded to amide group of PNVA polymer. Fluorescence experiment indicated that the characteristic emission intensity of terbium ion was greatly increased and possibly sensitized by lanthanum ion (or gadolinium). Moreover, the wavelengths of terbium characteristic emissions were changed slightly. Also the characteristic emission intensity of terbium ion doped with lanthanum ion was better than that with gadolinium ion.

One-step nanomorphology control of self-organized projection coronas in uniform polymeric nanoparticles.

Uniform polymeric nanoparticles with various morphologies of projection coronas like the viruses in the coronavirus group have been formed by the self-organization of macromolecular chains polymerizing in a dispersion system of styrene (St), acrylonitrile (AN) and poly(ethylene glycol) monomethoxymonomethacrylate (PEGm) in a polar solvent (water/ethanol). An increase in the water composition reduced the crystallization degree of AN units, resulting in a variety of the nanoparticle morphology such as the increased particle size, the reduced projection size, the increased projection number, and the decreased inter-projection distance. The difference in the projection morphology strongly affected a dispersibility in water.

[Spectra studies on the interaction of Mn2+ and poly N-isopropylacrylamide].

The interaction of Mn2+ and poly (N-isopropylacrylamide) (PNIPAAm) was studied by using UV-Vis, FTIR and fluorescence spectroscopic methods. The results indicated that Mn2+ could be bonded to oxygen atoms of carbonyl in PNIPAAm and form the complex of Mn2+ -PNIPAAm. It was found that there existed efficient Förster energy transfer from Mn2+ to PNIPAAm due to the emission spectra of Mn2+ overlapping the excitation spectra of PNIPAAm and that the emission peak of Mn2+ at 561 nm disappeared in Mn2+ -PNIPAAm complex. Therefore the fluorescence intensity at 307 nm was increased by 314%.