施氮对水稻土N2O释放及反硝化功能基因(narG/nosZ)丰度的影响

以紫潮泥和红黄泥两种不同质地的水稻土壤作为研究对象,通过室内培养试验,分析施用硝态氮肥对N2O释放和反硝化基因(narG/nosZ)丰度的影响,并探讨反硝化基因丰度与N2O释放之间的关系。结果表明,施用硝态氮显著增加两种水稻土的N2O释放量。在72h培养过程中,施氮改变了紫潮泥反硝化基因(narG/nosZ)的丰度,但并未明显影响红黄泥反硝化基因(narG/nosZ)丰度。通过双变量相关分析发现,除了紫潮泥narG基因外,其它的反硝化基因丰度和N2O释放之间并没有显著相关性。     

灭幼脲Ⅲ号对马尾松林昆虫群落多样性的影响研究

１９９５年７月至１９９６年６月在湘中丘陵区马尾松林内用灭幼脲Ⅲ号作的喷药试验结果表明,灭幼脲Ⅲ号不仅直接影响鳞翅目昆虫的物种组成主多样性水平,而且对膜翅目昆虫（主要是蚂蚁）和蜘蛛的物种组成及多样性水平有间接影响。在时间过程中,施药区鳞翅目和直翅目昆虫的多样性水平有一定程度的下降,但下降程度不如对照区大,膜翅目和蜘蛛的多样性水平则有较大程度的上升,因此林内昆虫群落趋于相对稳定。由于药剂对蚜虫种群无影     

In vitro biological activities of transmembrane superantigen staphylococcal enterotoxin A fusion protein

The bacterial superantigen staphylococcal enterotoxin A (SEA) stimulates T cells bearing certain TCR V domains when binding to MHC II molecules, and is a potent inducer of CTL activity and cytokine production. Antibody-targeted SEA such as C215 Fab-SEA and C242 Fab-SEA has been investigated for cancer therapy in recent years. We have previously reported significant tumor inhibition and prolonged survival time in tumor-bearing mice treated with a combination of both C215Fab-SEA and Ad IL-18 (Wang et al., Gene Therapy 8:542–550, 2001). In order to develop SEA as an universal biological preparation in cancer therapy, we first cloned a SEA gene from S. aureus (ATCC 13565) and a transmembrane (TM) sequence from a c-erb-b2 gene derived from human ovarian cancer cell line HO-8910, then generated a TM-SEA fusion gene by using the splice overlap extension method, and constructed the recombinant expression vector pET-28a-TM-SEA. Fusion protein TM-SEA was expressed in E. coli BL21(DE3)pLysS and purified by using the histidine tag in this vector. Purified TM-SEA spontaneously associated with cell membranes as detected by flow cytometry. TM-SEA stimulated the proliferation of both human PBLs and splenocytes derived from C57BL/6 (H-2b) mice in vitro. This study thus demonstrated a novel strategy for anchoring superantigen SEA onto the surfaces of tumor cells without any genetic manipulation.Abbreviations SEA staphylococcal enterotoxin A - TM transmembrane - NK cell natural killer cell - CTL cytotoxic T lymphocyte Drs W. Ma and H. Yu are joint corresponding authors for this article.     

The vascularization,innervation and myogenesis of early regenerated tail in Gekko japonicus

Journal of Molecular Histology - Many species of lizards are capable of tail regeneration. There has been increased interest in the study of lizard tail regeneration in recent years as it is an...     

An Eimeria vaccine candidate based on Eimeria tenella immune mapped protein 1 and the TLR-5 agonist Salmonella typhimurium FliC flagellin

Immune mapped protein-1 (IMP1) is a new protective protein in apicomplexan parasites, and exits in Eimeria tenella. But its structure and immunogenicity in E. tenella are still unknown. In this study, IMPI in E. tenella was predicted to be a membrane protein. To evaluate immunogenicity of IMPI in E. tenella, a chimeric subunit vaccine consisting of E. tenella IMP1 (EtIMP1) and a molecular adjuvant (a truncated flagellin, FliC) was constructed and over-expressed in Escherichia coli and its efficacy against E. tenella infection was evaluated. Three-week-old AA broiler chickens were vaccinated with the recombinant EtIMP1-truncated FliC without adjuvant or EtIMP1 with Freund’s Complete Adjuvant. Immunization of chickens with the recombinant EtIMP1-truncated FliC fusion protein resulted in stronger cellular immune responses than immunization with only recombinant EtIMP1 with adjuvant. The clinical effect of the EtIMP1-truncated FliC without adjuvant was also greater than that of the EtIMP1 with adjuvant, which was evidenced by the differences between the two groups in body weight gain, oocyst output and caecal lesions of E. tenella-challenged chickens. The results suggested that the EtIMP1-flagellin fusion protein can be used as an effective immunogen in the development of subunit vaccines against Eimeria infection. This is the first demonstration of antigen-specific protective immunity against avian coccidiosis using a recombinant flagellin as an apicomplexan parasite vaccine adjuvant in chickens.     

Association analysis of fiber quality traits and exploration of elite alleles in Upland cotton cultivars/accessions （Gossypium hirsutum L.）

Exploring the elite al eles and germplasm acces-sions related to fiber quality traits wil accelerate the breeding of cotton for fiber quality improvement. In this study, 99 Gossypium hirsutum L. accessions with diverse origins were used to perform association analysis of fiber quality traits using 97 polymorphic microsatel ite marker primer pairs. A total of 107 significant marker-trait associations were detected for three fiber quality traits under three different environments, with 70 detected in two or three environments and 37 detected in only one environment. Among the 70 significant marker-trait associations, 52.86% were reported previously, implying that these are stable loci for target traits. Furthermore, we detected a large number of elite al eles associated simulta-neously with two or three traits. These elite al eles were mainly from accessions col ected in China, introduced to China from the United States, or rare al eles with a frequency of less than＆amp;nbsp;5%. No one cultivar contained more than half of the elite al eles, but 10 accessions were col ected from China and the two introduced from the United States did contain more than half of these al eles. Therefore, there is great potential for mining elite al eles from germplasm accessions for use in fiber quality improvement in modern cotton breeding.