水葫芦生防菌Cercospora piaropi菌株BA-57的生物学特性

尾孢菌属的Cercospora piaropi是一种水葫芦生防真菌,有潜力被开发成为防除水葫芦的真菌除草剂。本试验研究了该菌BA-57菌株的生物学特性。结果表明,BA-57菌丝生长、产孢和孢子萌发的最适温度都为30℃,最适pH分别为7.6、10.0和9.0。光照处理对BA-57的菌丝生长以及产孢量无显著影响,而全黑暗有利于孢子萌发。碳源中,甘露醇最适于BA-57菌丝生长,而葡萄糖和蔗糖有利于BA-57产孢。BA-57菌丝生长和产孢的最佳氮源都是硝酸钠。蛋白胨和玉米粉对BA-57的孢子萌发有促进作用。湿度条件,在水滴中BA-57的孢子萌发率最高。     

Development and study of experimental C57BL/6 mouse lupus nephritis model induced by pristane

AIM To establish a C57BL/6 mouse lupus nephritis model induced by pristane and to explore the pathogenic mechanism of this model. METHODS Thirty C57BL/6 mice were randomly divided into 2 groups. The mice in model group were intraperitoneally injected with 0.5 mL pristane, while the mice in control group were injected with 0.5 mL normal saline. The state of health and survival of the animals were monitored during the whole experiment. The activation of macrophages, granulocytes, dendritic cells and B cells in spleen and the markers on B cells were detected by flow cytometry on the 10th day after injection. The serum levels of antinuclear antibodies (ANA) and anti-double strand DNA antibodies (anti-dsDNA) were measured every month after injection by indirect immunofluorescence assay, and proteinuria was checked mouthy by Albustix test strips. Eight months after injection, all mice were killed, and the kidneys were slided and stained with HE or PE-labeled IgG to analyze the expression of interferon-γ (IFN-γ) and interleukin-4 (IL-4). The evidence of glomerulonephritis was histopathologically observed, and the ultrastructural changes of the glomerulus were determined by transmission electron microscopy. RESULTS Ten days after the pristane injection, the populations of macrophages, granulocytes, dendritic cells and B cells were increased significantly compared with control mice (P<0.05). The expression of B7-1, B7-2 and MHC-II on the B cells was also increased (P<0.05). The serum levels of ANA and anti-dsDNA were increased from 3 to 8 months (P<0.05). Meanwhile, part of the mice showed different degrees of ascites, emaciation or even death, part of the mice had proteinuria 4 months later, and 8 months later, all of the model mice had proteinuria, with 1~20 g/L of urine protein. At the 8th month, a large number of heterotopic lymphoid tissues appeared in the abdominal cavity. The deposition of immune complexes in glomeruli and mesangial areas was serious. The expression of IFN-γ in the renal tissues was increased. Pathological damages such as lymphocyte infiltration, tissue necrosis and deposition of electron dense substances were obvious in the model mice. In control group, autoantibodies and proteinuria was not detected under the same experimental condition. Meanwhile, no evidence of glomerulonephritis in the control mice was observed. CONCLUSION The C57BL/6 mouse model of lupus nephritis induced by pristane is established successfully.     

一株产冠毒素新菌株发酵条件的初步研究

通过对产冠毒素新菌株洋葱假单胞菌Pseudom onas cepaciaY57培养温度和时间的研究,发现菌株Y57在碳源充足的情况下,不同培养温度对菌株的生长影响不明显,但影响菌株的产素能力,以32~18℃的变温培养为佳;接着运用正交试验确定了菌株的最佳培养基配方,即:葡萄糖(20 g/L),蛋白胨(1.5 g/L),FeC l3(15μmol/L),KH2PO4(4.0 g/L),K2HPO4(1.8 g/L),MgSO4.7H2O(0.2 g/L);最后根据试验结果,确定了摇瓶发酵的最适条件为:采用最佳培养基配方,32℃培养1 d,降温至18℃发酵2 d,冠毒素的效价由优化前的98μg/mL提高到128μg/mL,提高了30%左右。     

杂交中籼新组合协优57抗病、虫及耐旱耐淹性研究

协优５７ 中抗白叶枯病、稻瘟病,对纹枯病也有一定的抗性,在病区种植增产明显;田间抗稻飞虱能力较强;此外,还具有较强的耐旱、耐淹能力。     

Ontogenic and morphological study of gonadal formation in genetically-modified sex reversal XYPOS mice

Mammalian sexual fate is determined by the presence or absence of sex determining region of the Y chromosome (Sry) in the “bipotential” gonads. Recent studies have demonstrated that both male and female sexual development are induced by distinct and active genetic pathways. Breeding the Y chromosome from Mus m. domesticus poschiavinus (POS) strains into C57BL/6J (B6J) mice (B6J-XY^POS) has been shown to induce sex reversal (75%: bilateral ovary, 25%: true hermaphrodites). However, our B6N-XY^POS mice, which were generated by backcrossing of B6J-XY^POS on an inbred B6N-XX, develop as males (36%: bilateral testis with fertility as well as bilateral ovary (34%), and the remainder develop as true hermaphrodites. Here, we investigated in detail the expressions of essential sex-related genes and histological features in B6N-XY^POS mice from the fetal period to adulthood. The onsets of both Sry and SRY-box 9 (Sox9) expressions as determined spatiotemporally by whole-mount immunohistochemistry in the B6N-XY^POS gonads occurred 2–3 tail somites later than those in B6N-XY^B6 gonads, but earlier than those in B6J-XY^POS, respectively. It is possible that such a small difference in timing of the Sry expression underlies testicular development in our B6N-XY^POS. Our study is the first to histologically show the expression and ectopic localization of a female-related gene in the XY^POS testes and a male-related gene in the XY^POS ovaries. The results from these and previous experiments indicate that the interplay between genome variants, epigenetics and developmental gene regulation is crucial for testis development.     

Radix Pseudostellariae polysaccharide attenuates high fat diet induced hepatic insulin resistance in mice

AIM: To study the role of Radix Pseudostellariae polysaccharide (RPP) in hepatic insulin resistance.METHODS: Six-week-old C57BL/6J mice were randomly divided into low-fat diet (LFD) control group and high-fat diet (HFD) model group. After 16 weeks, intraperitoneal pyruvate tolerance test (IPPTT) was performed to determine the establishment of the HFD-induced hepatic insulin resistance model. HFD containing RPP (500 mg/kg) was given for 4 consecutive weeks. IPPTT, liver malondialdehyde (MDA) level and liver mitochondrial MDA level were measured. The protein levels of p-AKT (Ser473/Thr308), p-AMPK, nuclear factor E2-related factor 2 (Nrf2), NQO1 and IκBα in the liver tissues were measured by Western blot.RESULTS: After administration of RPP, a significant reduction in the levels of blood glucose and hepatic mitochondrial MDA was observed. The levels of p-AKT (Ser473/Thr308) and p-AMPK were significantly elevated in the liver tissues. The hepatic IκBα levels were up-regulated. RPP also enhanced the expression of Nrf2 system-regulated proteins NQO1 and HO-1 in the liver tissues.CONCLUSION: Radix Pseudostellariae polysaccharides effectively reduce HFD-induced hepatic insulin resistance in C57BL/6J mice and improves liver glucose metabolism by ameliorating HFD-impaired hepatic transduction of insulin signaling, activating Nrf2-associated signaling and inhibiting the expression of inflammatory signaling proteins.     

杂交中籼协优57群体性状与氮密效应的研究

试验结果表明 :杂交中籼协优 5 7群体性状及产量随着施氮量和栽插密度而异。施氮量与栽插密度两因素的交互效应大于因子简单效应之和 ,其作用极显著地影响着群体性状量的变动。处理组合的平均穗谷重、穗数和稻谷产量的变幅依次为 2 .60～ 3 .91g、2 3 0～ 3 0 1个 /m2 和 811.9～ 969.0g/m2     

甘薯新品种金山57的选育

１９８７－１９９２年选用优亲配制组合进行复合杂交，育成甘薯新品种金山５７，１９９３年通过专家技术鉴定和福建省农作物品种审定委员会的审定．该品种表现特早熟、高产、优质、抗病、耐旱及耐寒力较强和适应性较广等综合优良性状，尤其抗蔓割病、群Ⅰ薯瘟病、黑腐病和根腐病等多种病害，并较好地解决了高产与优质和高产与早熟难以兼顾的矛盾，是福建省“六五”以来甘薯育种攻关的一个突破．金山５７推广速度快，１９９１年全省示范种植面积９２６．７ｈｍ２，１９９２年示范推广１３８６６．７ｈｍ２，１９９３年全省６地市、３８县（市）区扩大推广４２２００ｈｍ２，１９９１－１９９３３年累计推广面积５６９９３．４ｈｍ２，增产薯干１４．６万ｔ，增加产值１．４７亿元。     

Rescue In Vitro Fertilization Method for Legacy Stock of Frozen Mouse Sperm

Sperm cryopreservation has been widely adopted for maintenance of the genetically engineered mouse (GEM). The cryopreserved sperm are being exchanged among many institutes worldwide. However, the recipients are not always able to obtain high fertilization rates with the frozen sperm shipped from senders. In this study, we cryopreserved mouse sperm via various methods and performed in vitro fertilization (IVF) in which the combination of methyl-beta-cyclodextrin for sperm preincubation and reduced glutathione for insemination was used (the MBCD-GSH IVF). In addition, frozen sperm sent from the Jackson Laboratory (USA) were thawed and used for IVF in the same manner. The fertilization rates of both the sperm cryopreserved via the methods applied in some countries and the cryopreserved GEM sperm improved when used with the MBCD-GSH IVF method. Therefore, we strongly believe that the MBCD-GSH IVF method brings about relatively high fertilization rates with any strain of frozen mouse sperm.     

Synthesis and Neuroprotective Action of Xyloketal Derivatives in Parkinson’s Disease Models

Parkinson’s disease (PD) is the second most common neurodegenerative disease affecting people over age 55. Oxidative stress actively participates in the dopaminergic (DA) neuron degeneration of PD. Xyloketals are a series of natural compounds from marine mangrove fungus strain No. 2508 that have been reported to protect against neurotoxicity through their antioxidant properties. However, their protection versus 1-methyl-4-phenylpyridinium (MPP+)-induced neurotoxicity is only modest, and appropriate structural modifications are necessary to discover better candidates for treating PD. In this work, we designed and synthesized 39 novel xyloketal derivatives (1–39) in addition to the previously reported compound, xyloketal B. The neuroprotective activities of all 40 compounds were evaluated in vivo via respiratory burst assays and longevity-extending assays. During the zebrafish respiratory burst assay, compounds 1, 9, 23, 24, 36 and 39 strongly attenuated reactive oxygen species (ROS) generation at 50 μM. In the Caenorhabditis elegans longevity-extending assay, compounds 1, 8, 15, 16 and 36 significantly extended the survival rates (p < 0.005 vs. dimethyl sulfoxide (DMSO)). A total of 15 compounds were tested for the treatment of Parkinson’s disease using the MPP+-induced C. elegans model, and compounds 1 and 8 exhibited the highest activities (p < 0.005 vs. MPP⁺). In the MPP+-induced C57BL/6 mouse PD model, 40 mg/kg of 1 and 8 protected against MPP+-induced dopaminergic neurodegeneration and increased the number of DA neurons from 53% for the MPP+ group to 78% and 74%, respectively (p < 0.001 vs. MPP+ group). Thus, these derivatives are novel candidates for the treatment of PD.