Synthesis of Citrinin Artificial Antigen and Its Coupling Ratio Determination

[Objective] This study was to establish a method for the rapid and accurate detection of the coupling ratio of artificial antigen. [Method] Artificial synthetic antigen of citrinin （CIT） was first conjugated with vector protein bovine serum albumin （BSA） and then identified by SDS-PAGE electrophoresis,and its coupling ratio was measured by UV absorption and mass spectrometry. [Result] The identification result showed that artificial antigen of CIT was successfully coupled,and the coupling ratio was 8.4 by UV absorption while 6.0 by mass spectrometry. [Conclusion] The comparison experiment showed that mass spectrometry could rapidly identify the artificial antigen and accurately detect its coupling ratio. This study provided basis for the preparation of CIT antigen as well as the establishment of an for enzyme-linked immunosorbent assay （ELISA） for citrinin determination.

大豆浓缩蛋白——水产饲料的优质蛋白原料

传统上,鱼粉一直是鱼、虾饲料中的主要蛋白源.由于水产养殖业的迅猛发展,鱼粉供不应求的状况将会发生.

Selective Effect of Qinghaosu on Different Stages of Plasmodium falciparum in Vitro

Using highly synchronous cultures of Plasmodium falciparum in vitro,the susceptibi- lity of the different stages of the intraerythrocytic parasites to Qinghaosu (QHS) was assessed.The anti- parasitic effect of QHS was measured by comparing the changes of irradiation of^3 H-hypoxanthine in- corporated into the nucleic acids of parasites exposed to various concentrations of QHS at different stages of growth.It was found that the trophozoite stage of the parasite was the most sensitive to QHS, whereas the early ring stage was the least sensitive,and the sensitivities of the late ring and schizont stages fell between those of the early ring and trophozoite stages.The results revealed the correlation of stage-dependent effects of QHS with the blockade of the protein metabolism of the parasite.

Expression and Mutation of MAGE-A3 mRNA in Lung Cancer Tissues

Objective： To inwvetigate the expression of MAGE-A3 mRNA in tissue samples derived from lung cancers and to discuss the possibility of using MAGE-A3 antigens as a new peptide vaccine for inunotherapy for lung cancers. Methods： Tumor tissue samples of lung cancers and paired non-tumor tissues of the lung were obtaimed from 31 lung cancer patients. Total RNA was extracted and cDNA was synthesized. Nested polymernse chain reaction amplification using MAGE-A3 specific primer was performed to detect the expression of MAGE-A3. The 10 clones of 5 samples of MAGE-A3 mRNA positive PCR products were DNA sequenced by using DNAs sequencer （PE-377）. Results： Of 31 lung cancers, 26 （83.9%） expressed MACE-A3 mRNA. The expression of MAGE-A3 gene was not detectable in the adjacent lung tissues. The DNA sequencing confirmed that the target gene fragment in all 5 samples of PCR products was MACE-A3 cDNA. Point nmtations occurred in 4 samples （8 clones） detected （C^2773→T^2773; G^2807→A^2807） resulting in alternation of amino acid residue in one position （E^143→K）. Conclusion： （1） The MAGE-A3 gene was expressed exclusively in tumor tissues of the patients with lung cancer in China. This tumor rejection antigen may have potential to be used as a new peptide vaccine for immunotherapy for lung eancers. （2） There are two point mutations of MAGE-A3 gene sequence in some Chinese lung cancer patients.

Molecular mechanism of Radix astragali on improvement of insulin sensitivity of SD rats treated with low dose dexamethasone

Aim To reveal the main active components and the action mechanisms of Radix astragali on insulin sensitivity improvement, we have investigated the effects of polysaccharide portion and saponin portion of Radix astragali extracts on blood biochemical indices and related gene expression of dexamethasone-induced SD rats. Methods SD rats （6 per group） received 2 μg/day subcutaneous dexamethasone for 4 weeks plus same dose （10 g material/kg） of polysaccharide or saponin extracts of Radix astragali. Blood samples, kidney tissues and epididymal fat pads were taken at the end of the experiment. Serum triglyceride （TG）, total cholesterol （TC）, low density lipoprotein cholesterol （LDLC）, high density lipoprotein cholesterol （HDLC）, glucose （GLU） and insulin （INS） levels were measured, respectively, mRNA levels of angiotensinogen in kidney, adiponectin and leptin as well as TNF-α in epididymal fats were determined by RT-PCR assay using GAPDH gene as an internal control. Results Both of polysaccharide and saponin extracts of Radix astragali exhibited positive effects in reducing serum triglycerides, glucose, and insulin levels of dexamethasone-induced SD rats. The saponin group showed more improvements on quantitive insulin sensitivity check index （QUICKI） than the polysaccharide group did. Both of the extracts down-regulated kidney angiotensinogen and fat TNF-α mRNA levels while they were simultaneously up-regulating fat adiponectin and leptin mRNA levels. No significant difference was found between actions of the two extracts. Conclusion Both of polysaccharide and saponin extracts of Radix astragali can improve insulin sensitivity. This action might be closely related to down-regulation of angiotensinogen, TNF-α and up-regulation of adiponectin and leptin expression. The results partly explained the improvement of type Ⅱ diabetes and diabetic nephropathy by Radix astragali. The similar actions of the two crude extracts suggest that unknown key active compounds might exist in both and remain to be discovered.

Prognostic significance of preoperative and postoperative CK19 and CEA m RNA levels in peripheral blood of patients with gastric cardia cancer

AIM To evaluate the clinical and prognostic significance of preoperative and postoperative cytokeratin 19(CK19) and carcinoembryonic antigen(CEA) m RNA levels in peripheral blood of patients with gastric cardia cancer(GCC).METHODS We detected the preoperative and postoperative mR NA levels of CK19 and CEA in peripheral blood of 129 GCC patients by using reverse transcription-polymerase chain reaction and evaluated their clinical and prognostic significance by univariate Kaplan-Meier survival analysis and multivariate Cox proportional hazard analysis. A new prognostic model which stratified patients into three different risk groups was established based on the independent prognostic factors.RESULTS Elevated preoperative and postoperative CK19 and CEA mR NA levels in peripheral blood of GCC patients were associated with lymph node metastasis. Univariate analysis showed that tumor size, histological grade, depth of tumor invasion, lymph node metastasis, preoperative CK19 m RNA, and preoperative and postoperative CEA m RNA levels were correlated with the prognosis of GCC patients. The multivariate analysis showed that lymph node status(P = 0.018), preoperative CK19(P = 0.035) and CEA(P = 0.011) m RNA levels were independent prognostic factors for overall survival(OS). The 5-year OS rates for the low-, intermediate-, and high-risk groups were 48.3%, 22.6%, and 4.6%, respectively(P < 0.001).CONCLUSION Elevated preoperative CK19 and CEA mR NA levels may be regarded as promising biomarkers for predicting lymph node metastasis and poor prognosis in patients with GCC. This new prognostic model may help us identify the subpopulations of GCC patients with the highest risk.

Enhancement of CTLs induced by DCs loaded with ubiquitinated hepatitis B virus core antigen

AIM： To investigate whether hepatitis B virus （HBV） could induce a hepatitis B virus core antigen （HBcAg）specific cytotoxic T lymphocyte （CTL） response in vitro by dendritic cells （DCs） transduced with lentiviral vector-encoding ubiquitinated hepatitis B virus core antigen （LV-Ub-HBcAg）.METHODS： Recombinant LV-Ub-HBcAg were transfected into highly susceptible 293 T cells to obtain high virus titres, Bone marrow-derived DCs isolated from BALB/c mice were cultured with recombinant granulocyte-macrophage colony-stimulating factor and recombinant interleukin （IL）-4. LV-Ub-HBcAg, lentiviral vector-encoding hepatitis B virus core antigen （LV-HBcAg）, lentiviral vector （LV） or lipopolysaccharide were added to induce DC maturation, and the DC phenotypes were analyzed by flow cytometry. The level of IL-12 in the supernatant was detected by enzyme-linked immunosorbent assay （ELISA）. T lymphocytes were proliferated using Cell Counting Kit-8. DCs were cultured and induced to mature using different LVs, and co-cultured with allogeneic T cells to detect the secretion levels of IL-2, IL-4, IL-10and interferon-γ in the supernatants of T cells by ELISA. Intracellular cytokines of proliferative T cells were analyzed by flow cytometry, and specific CTL activity was measured by a lactate dehydrogenase release assay.RESULTS： LV-Ub-HBcAg-induced DCs secreted more IL-12 and upregulated the expression of CD80, CD86 and major histocompatibility class ]I, DCs sensitised by different LVs effectively promoted cytokine secretion; the levels of IL-2 and interferon-y induced by LV-Ub- HBcAg were higher than those induced by LV-HBcAg, Compared with LV-HBcAg-transduced DCs, LV-Ub- HBcAg-transduced DCs more efficiently stimulated the proliferation of T lymphocytes and generated HBcAgspecific cytotoxic T lymphocytes.CONCLUSION： LV-Ub-HBcAg effectively induced DC maturation. The mature DCs efficiently induced T cell polarisation to Thl and generated HBcAg-specific CTLs.

Helicobacter pylori's virulence and infection persistence define pre-eclampsia complicated by fetal growth retardation

AIM: To better understand the pathogenic role of Helicobacter pylori (H. pylori) in pre-eclampsia (PE), and whether it is associated or not with fetal growth retardation (FGR). METHODS: Maternal blood samples were collected from 62 consecutive pregnant women with a diagnosis of PE and/or FGR, and from 49 women with uneventful pregnancies (controls). Serum samples were evaluated by immunoblot assay for presence of specific antibodies against H. pylori antigens [virulence: cytotoxin-associated antigen A (CagA); ureases; heat shock protein B; flagellin A; persistence: vacuolating cytotoxin A (VacA)]. Maternal complete blood count and liver enzymes levels were assessed at delivery by an automated analyzer. RESULTS: A significantly higher percentage of H. pyloriseropositive women were found among PE cases (85.7%) compared to controls (42.9%, P < 0.001). There were no differences between pregnancies complicated by FGR without maternal hypertension (46.2%) and controls. Importantly, persistent and virulent infections (VacA/ CagA seropositive patients, intermediate leukocyte blood count and aspartate aminotransferase levels) were exclusively associated with pre-eclampsia complicated by FGR, while virulent but acute infections (CagA positive/ VacA negative patients, highest leukocyte blood count and aspartate aminotransferase levels) specifically correlated with PE without FGR. CONCLUSION: Our data strongly indicate that persistent and virulent H. pylori infections cause or contribute to PE complicated by FGR, but not to PE without feto-placental compromise.

Procedure for preparing peptide-major histocompatibility complex tetramers for direct quantification of antigen-specific cytotoxic T lymphocytes

AIM： To establish a simplified method for generating peptide-major histocompatibility complex （MHC） class I tetramers.METHODS： cDNAs encoding the extracellular domain of human lymphocyte antigen （HLA）-A＊0201 heavy chain （A2） and β2-microglobulin （132m） from total RNA extracted from leukocytes of HLA-A2＋ donors were doned into separate expression vectors by reverse transcription-polymerase chain reaction. The recombinant A2 and 132m proteins were expressed in ~/a oo/i^uain BL21（DE3） and recovered from the inclusion body fraction. Soluble A2 proteins loaded with specific antigen peptides were refolded by dilution from the heavy chain in the presence of light chain 132m and HLA-A2-restricted peptide antigens. The refolded A2 monomers were biotinylated with a commercial biotinylation enzyme （BirA） and purified by low pressure anion exchange chromatography on a Q-Sepharose （fast flow） column.The tetramers were then formed by mixing A2 monomers with streptavidin-PE in a molar ratio of 4：1. Flow cytometry was used to confirm the expected tetramer staining of CD8^＋ T cells.RESULTS： Recombinant genes for HLA-A＊0201 heavy chain （A2） fused to a BirA substrate peptide （A2-BSP） and mature β2m from HLA-A2＋ donor leukocytes were successfully doned and highly expressed in E. coli, Two soluble monomeric A2-peptide complexes were reconstituted from A2-BSP in the presence of 132m and peptides loaded with either human cytomegalovirus pp65495-503 peptide （NLVPMVATV,NLV; designated as A2-NLV） or influenza virus matrix protein Mp58-66 peptide （GILGFVFTL, GIL; designated as A2-GIL）. Refolded A2-NLV or A2-GIL monomers were biotinylated and highly purified by single step anion exchange column chromatography. The tetramers were then formed by mixing the biotinylated A2-NLV or A2-GIL monomers with streptavidin-PE, leading to more than 80% multiplicationas revealed by SDS-PAGE under non-reducing, unboiled conditions. Flow cytometry revealed that these tetramers could specifically bind to CD8^＋ T cells from a HLA-A2^＋ donor,but failed to bind to those from a HLA-A2- donor.CONCLUSION： The procedure is simple and efficient for generating peptide-MHC tetramers.

Construction of humanized carcinoembryonic antigen specific single chain variable fragment and mitomycin conjugate

AIM： To construct a new target-oriented conjugate of humanized carcinoembryonic antigen （CEA） specific single chain variable fragment （scFv） and mitomycin （MMC） against colorectal cancer, and to investigate its influence on the growth and apoptosis of colorectal cancer cells. METHODS： The primer was designed according to the gene sequence described in reference 16, which respectively contains restriction enzyme cleavage sites BamH I and EcoR I in its upstream and downstream. PCR was performed with the plasmid as template containing genes of humanized anti-CEA scFv. The product was digested by BamH I and EcoR I, and connected to an expression vector which also has the restriction enzyme cleavage sites BamH I and EcoR. Expression of the reaction was induced by isopropy-β -D-thiogalactoside （IPTG）. Then the expression product was covalently coupled with MMC by dextran T-40. The immunoreactivity of the conjugate against colorectal cancer cells as well as CEA was measured by enzyme linked immunosorbent assay （ELISA）. The inhibiting ratio of conjugate on the growth of colorectal cancer cells was also measured by ELISA. The effect of conjugate on the apoptosis of colorectal cancer cells was determined by flow cytometry （FCM）. RESULTS： Restriction endonuclease cleavage and gene sequencing confirmed that the expression vector was successfully constructed. Sodium dodecyl sulfate polyacrylamide gel electropheresis （SDS-PAGE） confirmed that this vector correctly expressed the fusion protein. ELISA confirmed that the conjugate had quite a strong immunoreactivity against colorectal cancer cells and CEA. The conjugate had inhibitory effects on colorectal cancer cells in a concentration-dependent manner and could induce apoptosis of colorectal cancer cells in a concentration-dependent manner.CONCLUSION： The CEA-scFv-MMC conjugate can be successfully constructed and is able to inhibit the growth and induce apoptosis of colorectal cancer cells.

Adenoviral-mediated localized CTLA-4Ig gene expression induces long-term allograft pancreas survival and donor-specific immune tolerance in rats

T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen 4 antibody （CTLA-4Ig）, is known to induce to T-cell into ＂anergy＂ by blocking the costimulatory B7-CD28 interaction. Either systemic or localized administration of CTLA-Ig has been shown to prolong allograft survival and induce donor-specific tolerance in some transplant models. In this study, we characterized the expression and immunosuppressive effectiveness of adenoviral-mediated CTLA-4Ig gene transfer. We demonstrated transduction of the allografts with AdCTLA-4Ig resulted in localized expression, permanent graft survival and stable donor-specific tolerance. In addition, by performing simultaneous dual-organ through a local expression of CTLA-4Ig via adenoviral-mediated transplantation, we targeted on immunosuppression gene transfer into pancreatic allografts.

Anti-enrofloxacin Antibody Production by Using Enrofloxacin-screened HSA as an Immunogen

A two-step zero-length cross-linking procedure using active esters was successfully adopted for conjugating en-rofloxacin (EF) to human serum albumin (HSA). The derived conjugate was characterized by UV spectrum and then usedfor immunization of BALB/C mice. In enzyme-linked immunosorbent assay (ELISA) and competitive inhibition ELISA ex-periments, the derived antiserum exhibited high antibody titer (greater than 1: 250 000) as well as varied cross-reactivity(from 97.8% to 161.7%) to three analogs of EF belonging to fluoroquinolones family. But over the concentration rangestudied, no significant cross-reactivity was observed to other group of antibiotics (chloramphenicol, oxytetracycline, sul-phamethoxazole and nysfungin). It was confirmed that the synthesized immunogen was highly antigenic and elicited specificantibody responses in BALB/C mice against EF.

Antifibrotic Effects of Genistein and Quercetin In Vitro

Objective: To study the antifibrotic effects of genistein(GE) and quercetin(QU) on rat hepatic stellate HSC-T6 cell proliferation stimulated with platelet-derived growth factor (PDGF), collagen synthesis and type I procollagen messenger RNA (mRNA) expression stimulated with transforming growth factor b1 (TGFb1). Methods: Cell proliferation was measured by crystal violet staining assay. Collagen synthesis was determined by 3H-proline incorporation assay. Type I procollagen mRNA level was determined by reverse transcription polymerase chain reaction (RT-PCR). Results: GE (25~70 mmolL-1) and QU (6.25~50 mmolL-1) concentration-dependently attenuated PDGF-driven HSC-T6 cell proliferative activity. TGFb1-stimulated collagen synthesis was also reduced. This was associated with a decrease in type I procollagen mRNA expression, indicating an effect at a pretranslational level. Conclusion: GE and QU may have therapeutic potential against liver fibrosis by regulating PDGF and TGFb1 actions.

Short-term intravenous interferon therapy for chronic hepatitis B

AIM:To investigate the therapeutic efficacy of short- term, multiple daily dosing of intravenous interferon (IFN) in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B. METHODS:IFN-β was intravenously administered at a total dose of 102 million international units (MIU) over a period of 28 d in 26 patients positive for HBeAg and HBV-DNA. IFN-beta was administered at doses of 2 MIU and 1 MIU on d 1, 3 MIU twice daily from d 2 to d 7, and 1 MIU thrice daily from d 8 to d 28. Patients were followed up for 24 wk after the end of treatment. RESULTS:Six months after the end of the treatment, loss of HBV-DNA occurred in 13 (50.0%) of the 26 patients, loss of HBeAg in 9 (34.6%), development of anti-HBe in 10 (38.5%), HBeAg seroconversion in 8 (30.8%), and normalization of alanine aminotransferase (ALT) levels in 11 (42.0%). CONCLUSION:This 4-wk long IFN-β therapy, which was much shorter than conventional therapy lasting 12 wk or even more than 1 year, produced therapeutic effects similar to those achieved by IFN-α or pegylated- IFN-α (peg-IFN). Fewer adverse effects, greater efficacy, and a shorter treatment period led to an improvement in patients’ quality of life. IFN-β is administered intravenously, whereas IFN-α is administered intramuscularly or subcutaneously. Because both interferons are known to bind to an identical receptor and exert antiviral effects through intracellular signal transduction, the excellent results of IFN-β found in this study may be attributed to the multiple doses allowed by the intravenous route.

Comparison of a monoclonal antigen stool test (Hp StAR) with the ^(13)C-urea breath test in monitoring Helicobacter pylori eradication therapy

AIM： To evaluate the agreement between a mAb-based stool test （HP STAR） and the urea breath test （UBT） in monitoring （H pylon） infection after eradication therapy. METHODS： Patients with discordant results on UBT and Hp STAR underwent endoscopy with biopsies for rapid urease test, culture, and histology to confirm H pylori status. RESULTS： Among 250 patients （50±14 years）, 240 （96.0%） had concordant UBT and Hp STAR tests with a significant correlation between DOB and A values （R = 0.87; P〈0.0001）. The remaining 10 （4.0%） patients had discordant tests （positive Hp STAR and negative UBT） with the Hp STAR inaccurate in five cases （false positive） and UBT inaccurate in the other five cases （false negative）. The “maximal expected” sensitivity, specificity, ＋PV, -PV, ＋LR, and -LR were 91%, 100%, 100%, 97.4%, ∞, and 8.2 respectively, for the UBT, and 100%, 97.4%, 91%, 100%, 38.8, and 0, respectively, for the Hp STAR. Overall accuracy for both tests was 98%. CONCLUSION： Both the UBT and the Hp StAR are equally accurate in monitoring H pylori infection. Nowadays, the choice of the “best” non-invasive H pylori test in the post-treatment setting should be done not only in terms of diagnostic accuracy but also in view of cost and local facilities.

Isolation and Characterization of Exosomes Derived from Tumor Cells Genetically Expressing Model Antigen

Tumor cell-derived exosomes have been proposed as non-cellular nanomeric vaccine which could induce potent anti- tumor immune response in mice. In order to develop the protocols to prepare tumor cell-derived exosomes for basic research and clinical trail, we isolated exosomes from ovalbumin (OVA)-expressing thymoma cells EG.7-OVA by various preparation methods. We demonstrate the non-sedimentation method is simple, rapid, efficient with higher yield and purity of exosomes. EG.7-OVA-derived exosomes are 40-100 nm in diameter sequestered by lipid bi-layer, and contain rich heat shock protein (HSP) and OVA. The result of the size distribution determination is consistent with the calculation by the visual microscopic inspection, with 90.4% particles at the range of 50-90 nm. Moreover, as a model antigen of the EG.7 cells, OVA concentra- tion in EG.7-derived exosomes can be regarded as a good quality control parameter. Therefore, we have established a platform to efficiently prepare exosomes for tumor immunotherapy.

Cytotoxic T-lymphocyte antigen 4 gene polymorphisms and susceptibility to chronic hepatitis B

AIM： To assess the three polymorphJsm regions within cytotoxic T-lymphocyte antigen 4 （CTLA-4） gene, a C/T base exchange in the promoter region-318 （CTLA-4 -318C/T）, an A/G substitution in the exon 1 position 49 （CTLA-4 49A/G）, a T/C substitution in 1172 （CTLA-4 -1172T/C） in patients with chronic hepatitis B. METHODS： Fifty-one patients with chronic hepatitis B virus infection and 150 healthy subjects were recruited sequentially as they presented to the hepatic clinic. Classification of chronic hepatitis B virus （HBV）-infected patients was as asymptomatic carrier state （26 patients） and chronic hepatitis B （25 patients）. Genomic DNA was isolated from anti-coagulated peripheral blood Bully coat using Miller＇s salting-out method. The presence of the CTLA-4 gene polymorphisms was determined using polymerase chain reaction amplification refractory mutation system （ARMS）. RESULTS： We observed a significant association between -318 genotypes frequency （T＋C-, T＋C＋, T-C＋） and susceptibility to chronic hepatitis B （P=0.012, OR=0.49, 95%CI： 0.206-1.162）. However, we did not observe a significant association for ＋49 genotype frequency （T＋C＋, T＋C- T-C＋） and -1172 genotype frequency （C＋T＋, T＋C- C＋T-） and state of disease. CONCLUSION： Our results suggest that CTLA-4 gene polymorphisms may partially be involved in the susceptibility to chronic hepatitis B.

Phage displaying peptides mimic schistosoma antigenic epitopes selected by rat natural antibodies and protective immunity induced by their immunization in mice

AIM: To obtain the short peptides mimic antigenic epitopes selected by rat natural antibodies to schistosomes, and to explore their immunoprotection against schistosomiasis in mice.METHODS: Adults worm antigens (AWA) were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked transferred immunoblotting methods with normal SD rat sera (NRS). The killing effects on schistosomula with fresh and heat-inactivated sera from SD rats were observed. Then the purified IgG from sera of SD rats was used to biopan a phage random peptide library and 20 randomly selected positive clones were detected by ELISA and 2 of them were sequenced.Sixty female mice were immunized thrice with positive phage clones (0, 2nd, 4th wk). Each mouse was challenged with 40 cercariae, and all mice were killed 42 d after challenge. The worms and the liver eggs were counted. RESULTS: NRS could specifically react to the molecules of 75 000, 47 000, 34 500 and 23 000 of AWA. Sera from SD rats showed that the mortality rate of schistosomula was 76.2%, and when the sera were heat-inactivated in vitro, the mortality rate was decreased to 41.0% after being cultured for 48 h. The specific phages bound to IgG were enriched about 300-folds after three rounds of biopanning. Twenty clones were detected by ELISA, 19 of them bound to the specific IgG of rat sera. Immunization with these epitopes was carried out in mice. Compared with the control groups, the mixture of two mimic peptides could induce 34.9% (P = 0.000) worm reduction and 67.6% (P = 0.000) total liver egg reduction in mice. Two different mimic peptides could respectively induce 31.0% (P = 0.001), 14.5% (P = 0.074) worm reduction and 61.2% (P = 0.000), 35.7% (P = 0.000) total liver egg reduction. The specific antibody could be induced by immunization of the mimic peptides, and the antibody titer in immunized mice reached more than 1:6 400 as detected by ELISA.CONCLUSION: Specific peptides mimic antigenic molecules can be obtained by biopanning the phage random peptide library and a partially protective immunity against schistosome infection can be stimulated by these phage epitopes in mice.

S-Scheme photocatalyst TaON/Bi_(2)WO_(6) nanofibers with oxygen vacancies for efficient abatement of antibiotics and Cr(VI):Intermediate eco-toxicity analysis and mechanistic insights

Enlightened by natural photosynthesis,developing efficient S-scheme heterojunction photocatalysts for deleterious pollutant removal is of prime importance to restore environment.Herein,novel TaON/Bi_(2)WO_(6) S-scheme heterojunction nanofibers were designed and developed by in-situ growing Bi_(2)WO_(6) nanosheets with oxygen vacancies(OVs)on TaON nanofibers.Thanks to the efficiently spatial charge disassociation and preserved great redox power by the unique S-scheme mechanism and OVs,as well as firmly interfacial contact by the core-shell 1D/2D fibrous hetero-structure via the in-situ growth,the optimized TaON/Bi_(2)WO_(6) heterojunction unveils exceptional visible-light photocatalytic property for abatement of tetracycline(TC),levofloxacin(LEV),and Cr(Ⅵ),respectively by 2.8-fold,1.0-fold,and 1.9-fold enhancement compared to the bare Bi_(2)WO_(6),while maintaining satisfactory stability.Furthermore,the systematic photoreaction tests indicate Ta-ON/Bi_(2)WO_(6) has the high practicality in the elimination of pollutants in aquatic environment.The degradation pathway of tetracycline and intermediate eco-toxicity were determined based on HPLC–MS combined with QSAR calculation,and a possible photocatalytic mechanism was elucidated.This work provides a guideline for designing high-performance TaON-based S-scheme photocatalysts with defects for environment protection.

Intestinal pseudo-obstruction:An uncommon condition with heterogeneous etiology and unpredictable outcome

Intestinal pseudo-obstruction (IPO) either acute or chronic is a condition including features of intestinal ileus in absence of mechanical obstruction. Our paper presents such a rare case of idiopathic IPO in a 53-year-old male patient with recurrent episodes of pseudo-obstruction, which were successfully resolved by anticholinesterase agents, motilin agonists or colonic decompression. However, the patient finally underwent total colectomy. Huge colonic dilatation was identified intraoperatorily, while histology showed a neuropathic variant of chronic intestinal pseudo-obstruction. Etiologic mechanisms and current therapeutic methods are reviewed in this paper, which concludes that IPO is a condition in which conservative treatment usually fails. Total colectomy with ileoanal pouch may be the only solution in these situations.