Effects of different postharvest treatments on the physiology and quality of 'Xiaobai' apricots at room temperature.

The effect of postharvest treatments on storage characteristics of harvested apricots in relation to fruit quality was investigated. 'Xiaobai' apricots treated with 1-methylcyclopropene (1-MCP), chlorine dioxide (ClO2), calcium, and heat in sealed container and then stored at 20 °C with 90 % relative humidity (RH) for 10 days. Results showed that the treatments could reduce respiration production and MDA content, delay softening, postharvest decay, the decrease of soluble solids (SSC), and visual changes. Furthermore, the polyphenol oxidase (PPO), polygalacturonase (PG), and pectin methylesterase (PME), superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) activities were reduced by treatments. Taken together, it is suggested that ClO2 treatment might be an effective way to maintain the quality of apricot fruit except 1-MCP treatment.

Effects of interleukin-4 or interleukin-10 gene therapy on trinitrobenzenesulfonic acid-induced murine colitis.

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by disturbance of pro-inflammatory cytokines and anti-inflammatory cytokines. Previous studies have demonstrated the effect of anti-inflammatory cytokines, such as interleukin-10 (IL-10) or IL-4 on IBD, but their data were controversial. This study further investigated the effect of IL-4 (IL-4), IL-10 and their combination on treatment of trinitrobenzenesulfonic acid (TNBS)-induced murine colitis. METHODS: pcDNA3.0 carrying murine IL-4 or IL-10 cDNA was encapsulated with LipofectAMINE 2000 and intraperitoneally injected into mice with TNBS-induced colitis. The levels of intestinal IL-4 and IL-10 mRNA were confirmed by quantitative-RT-PCR. Inflamed tissues were assessed by histology and expression of interferon (IFN)-γ, tumor necrosis factor (TNF)-α and IL-6. RESULTS: The data confirmed that IL-4 or IL-10 over-expression was successfully induced in murine colon tissues after intraperitoneal injection. Injections of IL-4 or IL-10 significantly inhibited TNBS-induced colon tissue damage, disease activity index (DAI) and body weight loss compared to the control mice. Furthermore, expression of IFN-γ, TNF-α and IL-6 was markedly blocked by injections of IL-4 or IL-10 plasmid. However, there was less therapeutic effect in mice injected with the combination of IL-4 and IL-10. CONCLUSIONS: These data suggest that intraperitoneal injection of IL-4 or IL-10 plasmid was a potential strategy in control of TNBS-induced murine colitis, but their combination had less effect.

Cytokine tumor necrosis factor alpha induces intestinal epithelial barrier dysfunction.

BACKGROUND AND AIMS: Epithelial barrier dysfunction is involved in a number of diseases in the body. The mechanism is to be further understood. The present study aimed to investigate the role of one of the common microbial products, flagellin (FGN), in the induction of intestinal epithelial barrier dysfunction. METHODS: We collected the colon epithelium specimens from 40 patients with ulcerative colitis (UC), 40 patients with Crohn's disease (CD) and 40 healthy volunteers. The expression of toll like receptors (TLR)5 of the specimens was assessed by RT-PCR and western blotting. The expression of tumor necrosis factor alpha (TNFα) and its role in compromising the barrier function in the intestinal epithelial cells, T84 cells, were observed by a cell culture model. RESULTS: The results showed that the expression of TLR5 was observed in the colon epithelium of healthy subjects that was increased in UC patients and further increased in CD patients. Treating T84 cells with FGN increased the expression of TNFα in the cells that caused the T84 cell apoptosis as well as compromised the T84 monolayer barrier function, which could be prevented by knocking down the gene of TNFα in T84 cells. CONCLUSIONS: We conclude that the human colon epithelial cells express detectable TLR5 that is increased in patients with CD and UC. The exposure to FGN can increase the expression of TNFα that further compromises the intestinal epithelial barrier function.

Therapeutic effect of indirubin-loaded bovine serum albumin nanoparticules on ulcerative colitis.

Indirubin is considered to have promising potential in the treatment of ulcerative colitis (UC). However, poor aqueous solubility and low bioavailability limit its clinical application. We produced indirubin-loaded bovine serum albumin nanoparticles (INPs) and characterized their drug encapsulation efficiency, drug-loading capacity, capacity to release indirubin in vitro and short-term physical stability. We also investigated the pharmacokinetics of INPs in mice. We then compared the curative effects of INPs and indirubin against dextran sulfate sodium-induced colitis in mice and 3D cultured biopsies from patients with UC. In the mouse model, the outcomes of INP treatment, including the disease activity index and serous levels of interleukin (IL)-1ß and IL-10, were significantly different from those of indirubin treatment. Similarly, when we administered INPs and indirubin to the ex vivo colonic tissues of patients with UC, the effect of INPs was stronger than that of indirubin for most antioxidant and anti-inflammatory biomarkers. The results of both the animal trial and ex vivo experiment indicate that the therapeutic effect of indirubin was further enhanced by the carrier system, making it a highly promising medical candidate for UC.

[Preparation of Pb2+ imprinted acrylic acid-co-styrene and analysis of its adsorption properties by FAAS].

With lead ion template, acrylic acid as functional monomer, potassium persulfate as initiator, strytrene as framework monomer, lead ion imprinted polymers (Pb(II)-IIPs) were prepared using free emulsion polymerization method. The structure and morphology of the polymers were analyzed by UV-spectra, FTIR and scanning electron microscopy. The adsorption/ desorption and selectivity for Pb2+ were investigated by flame atomic absorption spectrometry (FAAS) as the detection means. The results show that compared with non-imprinted polymers(NIPs), the Pb(II)-IIPs had higher specific adsorption properties and selective recognition ability for Pb(II). The relative selectivity coefficient of Pb(II)-IIPs for Pb(II) was 6.25, 6.18, 6.25 and 6.38 in the presence of Cd(II), Cu(II), Mn(II) and Zn(II) interferences, respectively. The absorption rate was the best at the pH of adsorbent solution of 6, Adsorption rate reached 96% during the 2.5 h static adsorption time. Using 3.0 mol x L(-1) HCI as the best desorption solvent to desorb the adsorbents, the desorbtion rate reached 98%. Under the best adsorption conditions, the adsorption capacity of Pb(II)-IIPs for Pb(II) was found to be 40. mg x g(-1).

Promoter hypermethylation and histone hypoacetylation contribute to pancreatic-duodenal homeobox 1 silencing in gastric cancer.

BACKGROUND AND AIMS: The expression of pancreatic-duodenal homeobox 1 (PDX1) in gastric cancer is aberrantly reduced. The aim of this study was to elucidate the regulation of DNA methylation and histone acetylation at the promoter for PDX1 silencing in gastric cancer. METHODS: PDX1 expression in response to demethylation and acetylation was detected in human gastric cancer cell lines by reverse transcription-polymerase chain reaction (PCR) and western blot. Four CpG islands within the 5'-flanking region of PDX1 gene were analyzed with their transcription activities being detected by dual luciferase assay. Promoter hypermethylation was identified in gastric cancer cell lines and cancer tissues by methylation-specific PCR or bisulfite DNA sequencing PCR analysis. Histone acetylation was determined by chromatin immunoprecipitation (ChIP) assay. RESULTS: Demethylation by 5'-aza-2'-deoxycytidine (5'-aza-dC) and/or acetylation by trichostatin A (TSA) restored PDX1 expression in gastric cancer cells. Hypermethylation was found in four CpG islands in six of seven cancer cell lines. However, only the distal CpG island located in the promoter fragment of PDX1, F383 (c.-2063 to -1681 nt upstream of the ATG start codon) displayed significant transcriptional activity that could be suppressed by SssI methylase and increased by 5'-aza-dC and TSA. More than 70% of the single CpG sites in F383 were methylated with hypermethylation of F383 fragment more common in gastric cancerous tissues compared with the paired normal tissues (P < 0.05). ChIP assay showed F383 was also associated with low hypoacetylation level of the histones. CONCLUSION: Promoter hypermethylation and histone hypoacetylation contribute to PDX1 silencing in gastric cancer.

Ultrasound-assisted synthesis of novel 4-(2-phenyl-1,2,3-triazol-4-yl)-3,4-dihydropyrimidin-(1H)-(thio)ones catalyzed by Sm(ClO(4))(3).

An efficient synthesis of novel 4-(2-phenyl-1,2,3-triazol-4-yl)-3,4-dihydro-pyrimidin-2(1H)-(thio)ones from 1,3-dicarbonyl compounds, 2-phenyl-1,2,3-triazole-4-carbaldehyde and urea or thiourea under ultrasound irradiation and using samarium perchlorate as catalyst is described. Compared with conventional methods, the main advantages of the present methodology are milder conditions, shorter reaction times and higher yields.

[Study on adsorption behavior of crosslinked polyarylonitrile for copper, lead, cadmium and zinc ions by atomic absorption spectrometry].

The crosslinked polymer polyacrylonitrile was synthesized by suspension polymerization using acrylonitrile and divinylbenzene. It has been used as adsorbent of some toxic heavy metals in environmental waters. Its adsorption for metals and the factors which affect the adsorption capacity were studied by atomic absorption spectrometry (AAS). The experimental results showed that under the optimal adsorption conditions, the pH of adsorbate solution was 5-6, static adsorption time was 1.5-2 h, and adsorption procedure was carried out at room temperature, polyacrylonitrile as adsorbent has high adsorption capacity (mg x g(-1)) for Cu2+, Pb2+, Cd2+ and Zn2+, which can reach 26.6, 45.2, 39.7 and 32.5 separately. Adsorption rate (%) was 83.6, 87.1, 85.3 and 86.7 respectively during the 1.5-2 h static adsorption time. It will be more than five-hour static adsorption time before adsorption rate reaches more than 96%. Using 0.10 mol x L(-1) chloride acid as the best desorption solvent to desorb the adsorbates, the recovery of them reached 95%. At the same time the adsorption mechanism of polymer was studied.

Copper(II) sulfamate: an efficient catalyst for the one-pot synthesis of 3,4-dihydropyrimidine-2(1H)-ones and thiones.

A simple, efficient procedure for the one-pot Biginelli condensation reaction of aldehydes, beta-ketoesters and urea or thiourea employing copper(II) sulfamate as a novel catalyst is described. Compared to the classical Biginelli reaction conditions, the present method has the advantages of good yields, short reaction times and experimental simplicity.

Early upregulation of cyclooxygenase-2 in human papillomavirus type 16 and telomerase-induced immortalization of human esophageal epithelial cells.

BACKGROUND AND AIM: Cyclooxygenase-2 (COX-2) plays an important role in the carcinogenesis of esophageal squamous cell carcinoma (ESCC). However, it is not clear whether COX-2 is involved in the early or late stage of the development of ESCC. The aim of this study was to investigate the role of COX-2 in the carcinogenesis of ESCC by an immortalized esophageal epithelial cell line. METHODS: Human papillomavirus type 16 (HPV16)-E6/E7 and human telomerase reverse transcriptase (hTERT) transfection were used for immortalization of esophageal epithelial cells. COX-2-specific RNA interference was used for the inhibition of COX-2 expression. RESULTS: An immortalized esophageal epithelial cell line, NE6-E6E7/hTERT, was established, which had high proliferation activity but failed to induce colony formation in soft agar. COX-2 expression was upregulated in the early process of immortalization, while COX-2 small interfering RNA (siRNA) decreased the Bcl-2 expression, increased the expression of Bax, and induced cell-cycle arrest at the G0/G1 phase in NE6-E6E7/hTERT cells. Expressions of p53, cyclinD1, and the ratio of hyperphosphorylated-RB/hypophosphorylated-RB were progressively increased after E6E7 and the subsequent hTERT transfections. These changes were accompanied by the alteration of COX-2 expression, but could be reversed by COX-2 siRNA (P < 0.05). P16 expression was significantly downregulated in NE6-E6E7 or NE6-E6E7/hTERT cells (P < 0.05), and was not affected by COX-2 siRNA. CONCLUSIONS: Our results suggest that induction of cyclooxygenase-2 is essential in the human papillomavirus type 16 and hTERT-induced immortalization of human esophageal epithelial cells, and that COX-2 inhibition may be a potential target to block the carcinogenesis of ESCC at the precancerous stage.

Establishment and characterization of a new cell line derived from human colorectal laterally spreading tumor.

AIM: To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS: A new cell line (LST-R1) originated from laterally spreading tumor was established. Properties of the cell line were characterized using scanning and transmission electron microscopy, immunohistochemistry method, cytogenetic analysis and nude mice xenograft experiments. In vitro invasion assay, cDNA microarray and Western blotting were used to compare the difference between the LST-R1 and other colorectal cancer cell lines derived from prudent colon cancer. RESULTS: Our study demonstrated that both epithelial special antigen (ESA) and cytokeratin-20 (CK20) were expressed in LST-R1. The cells presented microvilli and tight junction with large nuclei. The karyotypic analysis showed hyperdiploid features with structural chromosome aberrations. The in vivo tumorigenicity was also demonstrated in nude mice xenograft experiments. The invasion assay suggested this cell line has a higher invasive ability. cDNA microarray and Western blotting show the loss of the expression of E-cadherin in LST-R1 cells. CONCLUSION: We established and characterized a colorectal cancer cell line, LST-R1 and LST-R1 has an obvious malignant tendency, which maybe partially attributed to the changes of the expression of some adhesion molecules, such as E-cadherin. It is also a versatile tool for exploring the original and progressive mechanisms of laterally spreading tumor and the early colon cancer genesis.

N-[(2-Phenyl-2H-1,2,3-triazol-4-yl)methylene]-2-(2-(2-phenyl-2H-1,2,3-triazol-4-yl)-3-{2-[(2-phenyl-2H-1,2,3-triazol-4-yl)methyleneamino]ethyl}imidazolidin-1-yl)ethanamine.

The reaction of 2-phenyl-2H-1,2,3-triazole-4-carbaldehyde with triethylenetetramine leads to the formation of a new binucleating ligand, viz. the title compound, C(33)H(33)N(13), demonstrating that this structure has the potential for more flexible rational design and tailoring. The title molecule is rendered quite rigid by the formation of a five-membered imidazolidine ring and there are four independent instances of pi-pi interactions. Both sides of each of the three aromatic arms take part in these interactions, forming a neat three-dimensional array structure.

[Selection of matrix modifier for GF-AAS determination of trace lead in soil watered with waste water and its application].

The rapid and direct method of selection of the matrix modifier for the determination of trace lead in soil watered with waste water by graphite furnace atomic absorption spectrometry under the best matrix modifier selected has been developed. The effect of the matrix modifiers including NH4 Hz2PO4, (NH4)3PO4, NH4CI, Pd-Mg, NH4H2PO4+MgNO3+NH4NO3 etc. was determined by using graphite furnace atomic absorption spectroscopy. The results showed that NH4H2PO4 is the best matrix modifier for the determination of lead in soil watered with waste water, and the content of lead was determined by using 4.0 mg x L(-1) NH4H2PO4 as a matrix modifier, ashing and atomization temperature of 850 degrees C and 1600 degrees C, respectively, and rectifying background. The relative standard deviation of the method was 2.6%, and the recovery was in the range of 92.4%-104%.

Diaquabis(quinoxaline-2-carboxylato-kappa2N1,O)copper(II).

In the title compound, [Cu(C9H5N2O2)2(H2O)2], the Cu(II) ion lies on an inversion centre and has an elongated centrosymmetric octahedral environment, equatorially trans-coordinated by two N,O-bidentate quinoxaline-2-carboxylate ligands and axially coordinated by two water O atoms. Symmetry-related molecules are linked by strong O-H...O hydrogen bonds, involving the uncoordinated carboxyl O atom of the carboxylate group and the coordinated water molecules, to form a two-dimensional network. Weak intermolecular C-H...N interactions also stabilize the crystal structure.

[Speciation analysis of manganese in water sample using flame atomic absorption spectrometry with hydrolysis separation system].

A rapid and sensitive method for the sequential determination of Mn(II), Mn (lV) and Mn( VII) in water samples based on flame atomic absorption spectrometry with hydrolysis separation system has been developed. In the proper acidity, the manganese in different kind of speciation was separated by using hydrolysis acidity. The pH of sample containing manganese in different kind of speciation was adjusted to 10 by using NaOH solution, and at pH 10 of the medium, Mn( II) and M(IV) were precipitated as hydrolysis precipitation, while Mn(VII) remaining in the solution was determined by AAS. After that, hydrolysis precipitation of Mn( II) was solvated by adding sulfuric acid with pH 5 as solvent and determined by AAS. Finally, hydrolysis precipitation of Mn(IV) was solvated by adding sulfuric acid with pH 1 as solvent and determined by AAS. The recoveries are 93. 3%-99. 5% for Mn( II), 96. 7%-103% for Mn(IV) and 98. 2%-104% for Mn(VII), the relative standard deviations are 2. 7%, 3. 2% and 3. 1% respectively, and the detection limits are 0. 10 mg x L(-1).

Preventive and therapeutic effects of NF-kappaB inhibitor curcumin in rats colitis induced by trinitrobenzene sulfonic acid.

AIM: To ascertain the molecule mechanism of nuclear factor-kappaB (NF-kappaB) inhibitor curcumin preventive and therapeutic effects in rats' colitis induced by trinitrobenzene sulfonic acid (TNBS). METHODS: Sixty rats with TNBS-induced colitis were treated with 2.0% curcumin in the diet. Thirty positive control rats were treated with 0.5% sulfasalazine (SASP). Thirty negative control rats and thirty model rats were treated with general diet. Changes of body weight together with histological scores were evaluated. Survival rates were also evaluated. Cell nuclear NF-kappaB activity in colonic mucosa was evaluated by using electrophoretic mobility shift assay. Cytoplasmic IkappaB protein in colonic mucosa was detected by using Western Blot analysis. Cytokine messenger expression in colonic tissue was assessed by using semiquantitative reverse-transcription polymerase chain reaction. RESULTS: Treatment with curcumin could prevent and treat both wasting and histopathologic signs of rats with TNBS-induced intestinal inflammation. In accordance with these findings, NF-kappaB activation in colonic mucosa was suppressed in the curcumin-treated groups. Degradations of cytoplasmic IkappaB protein in colonic mucosa were blocked by curcumin treatment. Proinflammatory cytokine messenger RNA expression in colonic mucosa was also suppressed. CONCLUSION: This study shows that NF-kappaB inhibitor curcumin could prevent and improve experimental colitis in murine model with inflammatory bowel disease (IBD). The findings suggest that NF-kappaB inhibitor curcumin could be a potential target for the patients with IBD.

Expression of Helicobacter pylori AlpA protein and its immunogenicity.

AIM: To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori (H pylori) and to study the immunogenicity of adhesin AlpA. METHODS: Gene Ab, which was amplified from H pylori chromosomal DNA by PCR technique, was sequenced and the biological information was analyzed, and inserted into the Nco I and Not I restriction fragments of the expression vector pET-22b(+) using T4 DNA ligase. The resulting plasmid pET-AlpA was transformed into competent E.coli BL21(DE3) cells using ampicillin resistance for selection. Recombinant strains were incubated in 5 mL LB with 100 mug/mL ampicillin overnight at 37 degrees. Sonication of BL21(DE3)pET-22b(+)/AlpA was analyzed by Western blot to detect AlpA immunogenicity. RESULTS: The gene encoding AlpA protein was amplified by PCR with chromosomal DNA of H pylori Sydney strain (SS1) as templates. It revealed that AlpA DNA fragment amplified by PCR had approximately 1 500 nucleotides, compatible with the previous reports. The recombinant plasmid pET-22b(+)/AB was successfully constructed. DNA sequencing showed one open reading frame with the length of 588 bp. It encoded seven conservative regions that showed good antigenicity and hydrophobicity by Parker and Welling method. Furthermore, INTERNET EXPASY, NNPREDICT and ISREC predicted that it was a porin-like structure consisting of beta-pleated sheets that were embedded in the outer membrane. BLAST analyzed 836 767 protein sequences and found that the similar sequences were all belonging to H pylori OMP sequences. SDS-PAGE and scan analysis showed that the molecular weight of AB was 22.5 ku and recombinant protein amounted to 29% of the total bacterial protein, among which dissolved expression amounted to 21.9% of sonicated supernatant. The rAB purity amounted to 96% through affinity chromatography. Western blot analysis of rAB confirmed that it could be specially recognized by serum form rabbit immunized with AlpA and H pylori infected. CONCLUSION: Adhesin AlpA recombinant protein may be a potential vaccine for control and treatment of H pylori infection.

[Preparation oral liposome-encapsulated recombinant Helicobacter pylori heat shock protein 60 vaccine for prevention of Hp infection].

OBJECTIVE: To prepare oral liposome-encapsulated recombinant Helicobacter pylori (Hp) heat shock protein 60 (Hsp60) vaccine and investigate its effect against Hp infection in mice. METHODS: The recombinant vector PET-22(+)/Hsp60 was transformed into BL21(DE3) E.coli. The recombinant protein was purified with Ni-NTA agrose resin and the oral liposome-encapsulated vaccine was prepared with phosphatidyl choline and cholesterols using film method, with the size distribution of the folate liposomes measured by transmission electronic microscopy. BALB/c mice were divided into 5 groups and immunized by intragastric administration of PBS, liposome, rHsp60 plus choleratoxin (CT), liposome-encapsulated rHsp60, and liposome-encapsulated rHsp60 plus CT, respectively, given once a week for 4 weeks. All the mice were challenged by Hp for 3 times within two weeks following the last immunization and sacrificed 3 weeks after the last challenge. Hp detection was performed by fast urease test. Semi-quantitative assessment of the bacterial colonization density observation of the inflammation severity and gastric histopathology were carried out. RESULTS: The soluble expression product accounted for 27% of the total bacterial protein. The purity of recombinant fusion protein was about 95% after purification. The mean size of the folate liposomes was 0.7+/-0.4 mum. PBS or liposome alone showed no immune-enhancing effect, and rHsp60 plus CT, liposome-encapsulated rHsp60 and liposome-encapsulated rHsp60 plus CT had the protective rates against Hp infection of 73.3%, 66.7% and 86.7%, respectively. The latter 3 preparations effected significantly reduced Hp infection and alleviated the inflammation in the gastric mucosa of the mice challenged with Hp. CONCLUSION: The oral liposome may serve as a potential adjuvant for Hp vaccine in preventing Hp infection.

[Speciation analysis of chromium(VI) and chromium(III) in water sample using flame atomic absorption spectrometry with TOA-benzene extraction separation system].

A rapid and sensitive method for the sequential determination of Cr(VI) and Cr(III) in water samples based on flame atomic absorption spectrometry with TOA-benzene extraction separation system has been developed. In the H2SO4 medium. Cr(VI) in sample solution was extracted into the organic phase by using the TOA-Benzene and Cr(III) remained in the water phase. Cr(VI) in the organic phase and Cr(III) in the water phase were determined separately by AAS. This method is simple, fast and of microscale. The results obtained by this method agreed well with those obtained by conventional method. The recoveries are 95.0%-102% for Cr(VI) and 94.8-103% for Cr(III). The relative standard deviations were 2.9% for Cr(VI) and 2.6% for Cr(Ill). The system has enrichment effect for Cr(VI), and the detection limits are 6.6 microg x L(-1) for Cr(VI) and 0.20 mg x L(-1) for Cr(III). The maximum extracted amount of Cr(VI) by TOA was 4.6 mg x mL(-1).

Pathogenicty and immune prophylaxis of cag pathogenicity island gene knockout homogenic mutants.

AIM: To clarify the role of cag pathogenicity island (cagPAI) of Helicobacter pylori (H pylori ) in the pathogenicity and immune prophylaxis of H pylori infection. METHODS: Three pairs of H pylori including 3 strains of cagPAI positive wildtype bacteria and their cagPAI knockout homogenic mutants were utilized. H pylori binding to the gastric epithelial cells was analyzed by flow cytometry assays. Apoptosis of gastric epithelial cells induced by H pylori was determined by ELISA assay. Prophylaxis effect of the wildtype and mutant strains was compared by immunization with the sonicate of the bacteria into mice model. RESULTS: No difference was found in the apoptasis between cagPAI positive and knockout H pylori strains in respective of the ability in the binding to gastric epithelial cells as well as the induction of apoptosis. Both types of the bacteria were able to protect the mice from the infection of H pylori after immunization, with no difference between them regarding to the protection rate as well as the stimulation of the proliferation of splenocytes of the mice. CONCLUSION: The role of cagPAI in the pathogenicity and prophylaxis of H pylori infection remains to be cleared.