Synergistic interactions between Glomus mosseae and Bradyrhizobium japonicum in enhancing proton release from nodules and hyphae

Soybean (Glycine max L. Merr.) seedlings were inoculated with Glomus mosseae (GM) and Bradyrhizobium japonicum (BJ) together or separately to study the effect of interactions on net H⁺ effluxes of nodules or extraradical hyphae by in vivo vibrating electrode techniques. GM promoted three-fold the H⁺ effluxes of nodules on mycorrhizal lateral roots and BJ increased eight-fold the net H⁺ effluxes of hyphae developing in the vicinity of nodules on lateral roots. Increments in plant P content were positively and linearly correlated with the net H⁺ efflux of nodules and hyphae. It is concluded that increased H⁺ effluxes of nodules resulted from enhanced nitrogenase activities induced by the presence of the AM fungus in lateral roots. The results point to additive effects of interactions between mycorrhizal fungi and rhizobia in increasing the extent of acidification of the “nodulesphere” and the hyposphere.     

Pulmonary type II cell hypertrophy and pulmonary lipoproteinosis are features of chronic IL-13 exposure

Interleukin (IL)-13, a key mediator of Th2-mediated immunity, contributes to the pathogenesis of asthma and other pulmonary diseases via its ability to generate fibrosis, mucus metaplasia, eosinophilic inflammation, and airway hyperresponsiveness. In these studies, we compared surfactant accumulation in wild-type mice and mice in which IL-13 was overexpressed in the lung. When compared with littermate controls, transgenic animals showed alveolar type II cell hypertrophy under light and electron microscopy. Over time, their alveoli also filled with surfactant in a pulmonary alveolar proteinosis pattern. At the same time, prominent interstitial fibrosis occurs. Bronchoalveolar lavage fluid from these mice had a three- to sixfold increase in surfactant phospholipids. Surfactant proteins (SP)-A, -B, and -C showed two- to threefold increases, whereas SP-D increased 70-fold. These results indicate that IL-13 is a potent stimulator of surfactant phospholipid and surfactant accumulation in the lung. IL-13 may therefore play a central role in the broad range of chronic pulmonary conditions in which fibrosis, type II cell hypertrophy, and surfactant accumulation occur.     

Temporal properties of dual-peak responses of mouse retinal ganglion cells and effects of inhibitory pathways

Dual-peak responses of retinal ganglion cells (RGCs) are observed in various species, previous researches suggested that both response peaks were involved in retinal information coding. In the present study, we investigated the temporal properties of the dual-peak responses recorded in mouse RGCs elicited by spatially homogeneous light flashes and the effect of the inhibitory inputs mediated by GABAergic and/or glycinergic pathways. We found that the two peaks in the dual-peak responses exhibited distinct temporal dynamics, similar to that of short-latency and long-latency single-peak responses respectively. Pharmacological studies demonstrated that the application of exogenous GABA or glycine greatly suppressed or even eliminated the second peak of the cells’ firing activities, while little change was induced in the first peak. Co-application of glycine and GABA led to complete elimination of the second peak. Moreover, application of picrotoxin or strychnine induced dual-peak responses in some cells with transient responses by unmasking a second response phase. These results suggest that both GABAergic and glycinergic pathways are involved in the dual-peak responses of the mouse RGCs, and the two response peaks may arise from distinct pathways that would converge on the ganglion cells.     

Construction of a high density integrated genetic map for cucumber (Cucumis sativus L.)

The high-density consensus map was constructed based on the GY14 × PI 183967 map from an inter-subspecific cross and the extended S94 × S06 map from an intra-subspecific cross. The consensus map was composed of 1,369 loci, including 1,152 SSR loci, 192 SRAP loci, 21 SCAR loci and one STS locus as well as three gene loci of fruit external quality traits in seven chromosomes, and spanned 700.5 cM, of which 682.7 cM (97.5%) were covered by SSR markers. The average genetic distance and physical interval between loci were 0.51 cM and ~268 kbp, respectively. Additionally, the physical position of the sequence-associated markers aligned along the assembled cucumber genome sequence established a relationship between genetic maps and cucumber genome sequence and to a great extent validated the order of markers in individual maps and consensus map. This consensus map with a high marker density and well-ordered markers is a saturated and reliable linkage map for genetic analysis of cucumber or the Cucurbitaceae family of plants.     

圆唇散白蚁补充生殖蚁的类型与建群能力

摘要: 【目的】为了探讨圆唇散白蚁Reticulitermes labralis补充生殖蚁对巢群稳定和发展的作用。【方法】对野外巢群进行调查研究, 及对婚飞成虫通过雌雄配对与补充生殖蚁隔离巢群进行人工饲养的对比研究。【结果】在野外巢群只发现1对原始蚁王蚁后, 而补充生殖蚁的数量最多可达到689头/巢。圆唇散白蚁有3种类型的补充生殖蚁, 即由工蚁转化来的无翅型补充生殖蚁、若蚁转化来的翅芽型补充生殖蚁和末龄若蚁羽化来的拟成虫型补充生殖蚁。实验室条件下婚飞配对群体和隔离群体建群1个月后的存活率分别为64%和96%。建巢初期婚飞配对群体的子代数目增长缓慢, 2个月时的群体数量为6.3±1.54, 10个月时的群体数量也仅为8.4±1.47; 而隔离建群补充生殖蚁2个月时的群体数量为52.4±6.44, 10个月时的群体数量为164.3±20.85, 都高于婚飞配对群体。 此外, 野外巢群的补充蚁后跟原始蚁后一样都具有发达的卵巢。【结论】在圆唇散白蚁中补充生殖蚁是白蚁巢群主要的繁殖力量, 也是建立新巢群的重要繁殖品级。     

Proteome analysis of hepatocellular carcinoma by two-dimensional difference gel electrophoresis: novel protein markers in hepatocellular carcinoma tissues

Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p 相似文献   

Ungulate bocaparvovirus 4 and rodent bocavirus are different genotypes of the same species of virus

Bocaviruses are associated with many human infectious diseases, such as respiratory tract infections, gastroenteritis, and hepatitis. Rats are known to be reservoirs of bocaviruses, including rodent bocavirus and rat bocavirus. Recently, ungulate bocaparvovirus 4, a known porcine bocavirus, has also been found in rats. Thus, investigating bocaviruses in rats is important for determining the origin of the viruses and preventing and controlling their transmission. To the best of our knowledge, no study to date has investigated bocaviruses in the livers of rats. In this report, a total of 624 rats were trapped in southern China between 2014 and 2017. Liver and serum samples from rats were tested for the prevalence of bocaviruses using PCR. Sequences related to ungulate bocaparvovirus 4 and rodent bocavirus were detected in both liver and serum samples. Interestingly, the prevalence of ungulate bocaparvovirus 4 (reference strain:KJ622366.1) was higher than that of rodent bocavirus (reference strain:KY927868.1) in both liver (2.24% and 0.64%, respectively) and serum samples (2.19% and 0.44%, respectively). The NS1 regions of ungulate bocaparvovirus 4 and rodent bocavirus related sequences displayed over 84% and 88% identity at the nucleic acid and amino acid levels, respectively. Furthermore, these sequences had similar genomic structure, genomic features, and codon usage bias, and shared a common ancestor. These viruses also displayed greater adaptability to rats than pigs. Our results suggested that ungulate bocaparvovirus 4 and rodent bocavirus may originate from rats and may be different genotypes of the same bocavirus species.