新型复合型生物絮凝剂的制备与应用研究

目的:为了得到高效实用的复合型微生物絮凝剂.方法:利用甘蔗渣作为廉价底物,进行复发酵培养:前期为3d,后期为1d,温度为30℃;初始pH值为7.2;同时以珠江河水作为实验水源,对其性能进行研究.结果:复合型微生物絮凝剂对水的浊度、色度去除最佳投加量为12mL/L,同时考虑到其实际使用,制成含水率为80%左右的干粉,试验其对水中TP、邻苯二甲酸脂的去除效果,其最佳投加量为0.21 mg/L.     

Dauricine induces apoptosis,inhibits proliferation and invasion through inhibiting NF‐κB signaling pathway in colon cancer cells

Dauricine, a bioactive component of Asiatic Moonseed Rhizome, has been widely used to treat a large number of inflammatory diseases in traditional Chinese medicine. In our study, we demonstrated that dauricine inhibited colon cancer cell proliferation and invasion, and induced apoptosis by suppressing nuclear factor‐kappaB (NF‐κB) activation in a dose‐ and time‐dependent manner. Addition of dauricine inhibited the phosphorylation and degradation of IκBα, and the phosphorylation and translocation of p65. Moreover, dauricine down‐regulated the expression of various NF‐κB‐regulated genes, including genes involved cell proliferation (cyclinD1, COX2, and c‐Myc), anti‐apoptosis (survivin, Bcl‐2, XIAP, and IAP1), invasion (MMP‐9 and ICAM‐1), and angiogenesis (VEGF). In athymic nu/nu mouse model, we further demonstrated that dauricine significantly suppressed colonic tumor growth. Taken together, our results demonstrated that dauricine inhibited colon cancer cell proliferation, invasion, and induced cell apoptosis by suppressing NF‐κB activity and the expression profile of its downstream genes. These findings provide evidence for a novel role of dauricine in preventing or treating colon cancer through modulation of NF‐κB singling pathway. J. Cell. Physiol. 225: 266–275, 2010. © 2010 Wiley‐Liss, Inc.     

Erk is involved in the differentiation induced by diallyl disulfide in the human gastric cancer cell line MGC803

Diallyl disulfide (DADS) is a major constituent of garlic. Previously, we found that DADS both inhibited proliferation in human gastric cancer cells in vitro and in vivo, and induced G2/M arrest. In this study, we investigated whether this differentiation effect was induced by DADS in human gastric cancer MGC803 cells, and whether it was related to an alteration in ERK activity. The results showed that the growth of MGC803 cells was inhibited by DADS. Cells treated with DADS displayed a lower nucleocytoplasmic ratio and tended to form gland and intercellular conjunction structures. The ConA-mediated cell agglutination ratio and cells’ ALP specific activity decreased. In MGC803 cells, dye transfer was limited to a few cells neighbouring the dye-injected cell and to a depth of 1–2 layers beneath the scrape site. However, after treatment with DADS, the LY (Lucifer Yellow) was transferred to several cells immediately neighbouring the microinjected cell and to a depth of 2–4 cell layers from the scrape site. This indicated that DADS induced differentiation in MGC803 cells. Western blot analysis revealed that although DADS did not influence the quantity of ERK1/2 protein expressed, it did decrease its phosphorylation in a concentration-dependent manner, compared with the controls. At 30 mg·L⁻¹, DADS inhibited the activation of ERK1/2 in 15–30 min. These results suggested that the DADS-induced differentiation of MGC803 cells involved an alteration of the ERK1/2 signaling pathway.     

Molecular evolution of adomet synthetase by DNA recombination with a novel Separate-Mixing method

We describe a new approach to in vitro DNA recombination termed the Separate-Mixing method in this study. The reaction process of this method consists of two stages: at the first stage the reaction was implemented in two parallel teams, which generated random recombination by template-switching of growing poly-nucleotides from primers in the presence of unidirectional single-stranded DNA fragments used as templates, and then both teams were mixed together for further extension and recombination of DNA sequences at the second stage. Due to this particular strategy, the reaction process was also accompanied by two other processes of DNA shuffling and StEP simultaneously. Two AdoMet synthetase genes, sam2 from Saccharomyces cerevisiae and metK from Escherichia coli, which have only 56% homology on the DNA level, were used for recombination with the Separate-Mixing method. DNA recombination was available after a single round of reaction. When 10 randomly selected recombinants were sequenced, an unshuffled parental clone was not found, nor was unexpected insertion, deletion, or rearrangement detected. An evolved gene, sam’, was obtained after screening and selection, which could obviously increase the accumulation of AdoMet in S. cerevisiae. Published in Russian in Molekulyarnaya Biologiya, 2006, Vol. 40, No. 3, pp. 546–553. This article was submitted by the authors in English.     

Brief communication: Prenatal and early postnatal stress exposure influences long bone length in adult rat offspring

Stress during the prenatal and early postnatal periods (perinatal stress, PS) is known to impact offspring cognitive, behavioral, and physical development, but effects on skeletal growth are not clear. Our objective was to analyze effects of variable, mild, daily PS exposure on adult offspring long bone length. Twelve pregnant rat dams were randomly assigned to receive variable stress from gestational days 14–21 (Prenatal group), postpartum days 2–9 (Postnatal), both periods (Pre–Post), or no stress (Control). Differences in adult offspring tibia and femur length were analyzed among treatment groups. Mean tibia length differed among groups for males (P = 0.016) and females (P = 0.009), and differences for femur length approached significance for males (P = 0.051). Long bone length was shorter among PS‐exposed offspring, especially those exposed to postnatal stress (Postnatal and Pre–Post groups). Results persisted when controlling for nose–tail length. These differences might reflect early stunting that is maintained in adulthood, or delayed growth among PS‐exposed offspring. This study suggests that PS results in shorter long bones in adulthood, independently of effects on overall body size. Stunting and growth retardation are major global health burdens. Our study adds to a growing body of evidence suggesting that PS is a risk factor for poor linear growth. Am J Phys Anthropol 149:307–311, 2012. © 2012 Wiley Periodicals, Inc.     

A bursal pentapeptide (BPP-I), a novel bursal-derived peptide, exhibits antiproliferation of tumor cell and immunomodulator activity

The bursa of Fabricius (BF) is the central humoral immune organ unique to birds. Here, we isolated a novel bursal pentapeptide I (BPP-I), LGPGP, from BF. BPP-I could play inhibition effect on MCF-7 but not on CEF or Vero cell proliferation in vitro, and enhance antitumor factor p53 protein expression. Also, BPP-I stimulated antibody production in a dose-dependent manner in hybridoma cell. Furthermore, BPP-I could induce various immune responses in mice immunization experiments, including increase antibody production and cytokines IL-4 and IFN-γ level, and induce T-cell immunophenotyping. These results suggest that BPP-I is a potential immunomodulator of antitumor and immunity. The study could provide some novel insights on the probable candidate reagent for the antitumor and immune improvement.     

Gene expression profiling of hybridoma cells after bursal-derived bioactive factor BP5 treatment

Bursa of Fabricius is the acknowledged vital humoral immune system for B cell differentiation and antibody production. To study the molecular mechanism underlying the effect of bursal-derived BP5, we used gene microarray to analyze the genomic expression profiling of BP5-treated hybridoma cells. BP5 exhibited an immunomodulatory effect on antibody production in hybridoma cells and induced alterations in the gene expression profiles related to the immune-related biological processes, such as T cell activation and proliferation, B cell activation, B cell-mediated immunity, and cytokines cytokine production involved in immune response. In addition, 26 biological pathways associated with immunomodulatory functions were regulated in BP5-treated hybridoma cells, in which p53 signal pathway played an important role in antitumor. Among these regulated genes, 12 differentially expressed genes were verified by qRT-PCR. The activation of p53 activity by BP5 was further confirmed by p53 luciferase reporter assay and p53 expression. Our data revealed that bursal-derived BP5 could regulate various immune-related cellular processes, including antitumor factor p53 signal pathway, perhaps partially accounting for the reported immunomodulatory roles and novel antiproliferation on tumor cells functions of bursal-derived bioactive factor BP5.     

Cigarette smoking in male patients with chronic schizophrenia in a Chinese population: prevalence and relationship to clinical phenotypes

The high prevalence of smoking in schizophrenia of European background may be related to smoking's reducing clinical symptoms and medication side effects. Because smoking prevalence and its associations with clinical phenotypes are less well characterized in Chinese than European patients with schizophrenia, we assessed these smoking behaviors using clinician-administered questionnaires and the Fagerstrom Test for Nicotine Dependence (FTND) in 776 Chinese male schizophrenia and 560 control subjects. Patients also were rated on the Positive and Negative Symptom Scale (PANSS), the Simpson and Angus Extrapyramidal Symptom Rating Scale (SAES), and the Abnormal Involuntary Movement Scale (AIMS). We found that the schizophrenia patients had a higher lifetime incidence of smoking (79% vs 63%), were more likely to be heavy smokers (61% vs 31%), and had lower smoking cessation rates (4% vs 9%) (all p<0.0001) than controls. Among the schizophrenia patients smoking prevalence increased with age, with the largest difference from controls in the age cohort of 55-75 years: 75% vs 46% (p<0.0001). Among the schizophrenia smokers 73% started to smoke before the onset of their illness by an average of 7.6 years. The patients with schizophrenia who were current smokers scored significantly lower on the PANSS negative symptom subscore (p<0.005), and on the SAES symptom scale (p<0.04; Bonferroni corrected p>0.05) than the non-smoking patients. These results suggest that Chinese males with schizophrenia smoke more frequently than the general population. Further, smokers with schizophrenia may display fewer negative symptoms and possibly less parkinsonism than non-smokers with schizophrenia.     

Cigarette smoking and cognitive function in Chinese male schizophrenia: a case-control study

Schizophrenic patients have higher smoking rates than the general population. Studies show that smoking may be a form of self-medication in an attempt to alleviate cognitive deficits in schizophrenic patients of European background. This study examined the relationships between smoking and cognitive deficits in Chinese schizophrenic patients, which have previously received little systemic study. We recruited 580 male chronic patients meeting DSM-IV criteria for schizophrenia and 175 male control subjects who were matched on age and education. The subjects completed a detailed cigarette smoking questionnaire, the Fagerstrom Test for Nicotine Dependence (FTND), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Patients also were rated on the Positive and Negative Symptom Scale (PANSS), the Simpson and Angus Extrapyramidal Symptom Rating Scale (SAES), and the Abnormal Involuntary Movement Scale (AIMS). All five RBANS subscales except for the Visuospatial/Constructional index showed significantly lower cognitive performance for schizophrenics than normal controls. The schizophrenic smokers scored lower than the schizophrenic non-smokers on the RBANS total score and the Visuospatial/Constructional and Immediate Memory indices. Similarly, the control smokers scored lower than the control non-smokers on the RBANS total score and the Immediate Memory index . Also, the schizophrenic smokers consistently performed the poorest on the cognitive domains of the RBANS. Among the schizophrenic patients, smokers displayed significantly fewer negative symptoms than non-smokers. Using multivariate regression analysis the following variables were independently associated with the RBANS total score: years of education, PANSS negative symptom score, age at schizophrenia onset, and number of hospitalizations. Our results show that smoking is associated with significant cognitive impairment in both schizophrenic patients and normal controls, but the smokers with schizophrenia had a reduced level of negative symptoms, suggesting that the benefits of smoking for those with schizophrenia may be limited to certain aspects of a given clinical phenotype.