[Effects of mixed broadleaved tree species with pure Pinus massoniana plantation on soil microbial necromass carbon and organic carbon fractions]. / é©¬å°¾æ¾çº¯æž—æ··äº¤æ”¹é€ å¯¹åœŸå£¤å¾®ç”Ÿç‰©æ®‹ä½“ç¢³å’Œæœ‰æœºç¢³ç»„åˆ†çš„å½±å“.

Mixing native broadleaved tree species is a widely used method for renovating Pinus massoniana plantations. Soil microbial necromass carbon and organic carbon fractions are important parameters for evaluating the impacts of tree species mixing and soil organic carbon (SOC) stability. However, their responses to the mixing and renovation of P. massoniana plantation has not been understood yet. Here, we selected a pure P. massoniana plantation (PP) and a mixed P. massoniana and Castanopsis hystrix plantation, with ages of 16 (MP16) and 38 years (MP38), respectively, as the research objects. We quantified soil physical and chemical properties, microbial necromass carbon content, and organic carbon components at different soil layers to reveal whether and how the introduction of C. hystrix into P. massoniana plantation affected soil microbial necromass carbon and organic carbon components. The results showed that the mixed P. massoniana and C. hystrix plantation significantly reduced fungal necromass carbon content and the ratio of fungal/bacterial necromass carbon in the 0-20 cm and 20-40 cm soil layers. There were no significant differences in microbial necromass carbon contents, bacterial necromass carbon contents, and their contributions to SOC among the different plantations. The contribution of fungal necromass carbon to SOC was higher than that of bacterial necromass carbon in all plantation types. The contribution of soil mineral-associated organic carbon (MAOC) to SOC was higher than that of occluded particulate organic carbon (oPOC) and light-free particulate organic carbon (fPOC) for all plantation types. Mixing the precious broadleaved tree species (i.e., C. hystrix) with coniferous species (P. massoniana) significantly increased MAOC content and the contribution of MAOC, oPOC, and fPOC to SOC in the 0-20 cm and 20-40 cm soil layers. The MAOC of MP38 was significantly higher than that of PP in all soil layers and the MAOC of MP38 stands were significantly higher than MP16 stands in the 20-40 cm, 40-60 cm, and 60-100 cm soil layers, indicating that hybridization enhanced SOC stability and that the SOC of MP38 stands were more stable than MP16 stands. SOC and total nitrogen contents were the main environmental factors driving the changes in soil microbial necromass carbon, while soil total nitrogen and organically complexed Fe-Al oxides were the primary factors affecting organic carbon fraction. Therefore, SOC stability can be enhanced by introducing native broadleaved species, such as C. hystrix, during the management of the P. massoniana plantation.

[Immunoregulatory mechanisms of an optimal Chinese herbal monomer compound in mice with allergic rhinitis].

OBJECTIVE: To study the immunoregulatory effect of an optimal Chinese herbal monomer compound, which consists of three monomers, namely, icariin, baicalin and Astragalus saponin I, in a mouse model of allergic rhinitis. METHODS: A mouse model of allergic rhinitis was established by intraperitoneal injection of ovalbumin and aluminum hydroxide gel suspension. The splenic lymphocytes of the mice were separated, cultured in 96-well plates and divided into three groups: control group, concanavalin A group and compound group. Splenic lymphocyte proliferation was detected by cell counting kit-8 method at different time points. Cell cycle distribution was observed by flow cytometry (FCM) also at different time points. The changes of intracellular calcium concentration of splenic lymphocytes were measured by fluorescence microplate reader after the cells were incubated with fluorescence probe Fluo-3/AM. RESULTS: The Chinese herbal monomer compound could inhibit cell proliferation induced by concanavalin A (P<0.01). And the inhibition presented a time-effect relationship. With extending of the action time, the inhibition rate gradually increased and reached peak at the 48th hour. FCM test revealed the fact that concanavalin A could promote cells to enter into the mitosis by reducing the percentage of cells in G0/G1 phases while increasing the percentage of cells in S and G(2)/M phases. Compared with the concanavalin A, the compound could increase the percentage of cells in G(0)/G(1) phases and at the same time reduce the percentage of cells in S and G(2)/M phases at different time points, with the effect most significant at the 24th hour (P<0.05 or P<0.01). The results of the test taken by the fluorescence microplate reader revealed that the fluorescence value of the concanavalin A group increased with time in the previous 24 h while the compound could reduce this trend obviously, thus reduce the intracellular calcium concentration (P<0.01). CONCLUSION: The Chinese herbal monomer compound can inhibit the proliferation of cultured splenic lymphocytes of mice with allergic rhinitis. The effects of the compound of lowering intracellular calcium concentration and arresting cell cycle at G(0)/G(1) phases from entering into S and G(2)/M phases are responsible for its antiproliferation activity.

[Optimal combination of baicalin, icariin and Astragalus saponin I from a Chinese herbal compound Biminne].

OBJECTIVE: To study the optimal combined ratio of baicalin, icariin and Astragalus saponin I from a Chinese herbal compound Biminne. METHODS: Firstly, a mouse model of allergic rhinitis was established by intraperitoneal injection of ovalbumin (OVA) and aluminum hydroxide gel suspension, and the effective dose range of baicalin, icariin and Astragalus saponin I was detected by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt method. Secondly, 10 groups of combinations of baicalin, icariin and Astragalus saponin I assembled by U(10)(10(8)) form were employed to determine the optimal combination by means of analyzing of the inhibitory effect on the splenocyte proliferation. Finally, the effects of each effective ingredient and the optimal combination were compared by observing the splenocyte proliferation, the contents of interleukin-4 (IL-4), IL-5, interferon-gamma (IFN-gamma) in supernatant of the splenocyte cultures and the ratio of IL-4 to IFN-gamma in order to verify the result. RESULTS: Baicalin or icariin at concentrations ranging from 2 to 10 micromol/L, and Astragalus saponin I from 1 to 10 micromol/L effectively suppressed the splenocyte proliferation. When the proportion of baicalin, icariin and Astragalus saponin I was 1:2.14:2.65, the inhibitory effect was most remarkable. Further research confirmed the rationality of the optimal combination. CONCLUSION: An optimal combination of the major effective ingredients from Chinese herbal compound Biminne most effectively suppresses the proliferation of splenocytes from sensitized mice and regulates the cytokine secreting.

Effects of Chinese herbal formula Biminne in regulating endocrine-immune function in mice with airway allergy.

OBJECTIVE: To investigate the effects of Biminne, a traditional Chinese herbal formula, in regulating the endocrine-immune function in mice with airway allergy. METHODS: Forty BALB/c mice were randomly divided into four groups: control group, untreated group, Biminne group, and dexamethasone (Dex) group. The murine model of airway allergy was established by intraperitoneal injection sensitization and intranasal challenge with ovalbumin (OVA). On day 28, the mice were sacrificed and the sera were collected. The lung tissue of mice was removed for haematoxylin-eosin staining and the pathological changes were observed. The spleen cells of mice were isolated and the ratio of Th2/Th1 was determined by flow cytometry. The isolated spleen cells were also cultured in 24-well plates in the presence of concanavalin A and the supernatants were collected after 72-hour culture. Levels of interleukin-4 (IL-4), IL-5 and interferon-gamma (IFN-gamma) in the supernatants and the corticosterone level in sera were analyzed by enzyme-linked immunosorbent assay. RESULTS: Biminne significantly relieved the inflammatory reaction in the lung tissue of airway allergic mice. Compared with the control group, the Th2 cells in the untreated group increased, while the IFN-gamma level decreased and the ratio of Th2/Th1 increased significantly, showing a Th2 response priority. Biminne treatment could down-regulate the Th2 cells and their cytokines IL-4 and IL-5, and up-regulate the Th1 cells and their cytokine IFN-gamma. So the ratio of Th2/Th1 decreased significantly, shifting to the control level. In addition, Biminne also inhibited the reduction of the serum corticosterone of sensitized mice. CONCLUSION: The Chinese herbal formula Biminne can reverse the functional disorder of the endocrine-immune system, which may explain its therapeutic effects on airway allergic disease.

[Spatial distribution patterns and association of Loropetalum chinense population in karst hills of Guilin, Southwest China]. / æ¡‚æž—å²©æº¶çŸ³å±±æªµæœ¨ç§ç¾¤ç©ºé—´æ ¼å±€åŠå ¶å ³è”æ€§.

The spatial distribution and association of populations can reflect succession patterns and its adaptation strategies to the change of environmental factors, with important significance for vegetation restoration, reconstruction, and biodiversity conservation. We used the point-pattern analytical method to examine the spatial distribution and its association of the Loropetalum chinense population in karst hills of Guilin, China, based on field surveys. On the basis of Ripley K function, we used the pair-correlation function statistic derived to explore difference in the distribution patterns.We used Ripley L function to examine the spatial associations among the three diameter classes. The results showed that the diameter class structure of the population exhibited an irregular inverted "J" type, with the small diameter class occupying a large proportion, indicating an increased population structure with good regeneration capability. The individuals of the three diameter classes had a clumped distribution at the small scale. With the increases of spatial scales, the aggregation intensity gradually weakened and tended to be randomly distributed. There was an independent spatial association between individuals among the three diameter classes at small scale. As the scale increased, the spatial association between individuals with different diameter classes became positive or negative association. The greater the difference in diameter class of L. chinense population, the weaker their spatial correlation was, which might gradually turn into negative association. Our findings contributed to a clearer understanding of the ecological strategies and scale-dependent cha-racteristics of species coexistence and underlying mechanisms during the growth and development of L. chinense population in karst hills of Guilin, providing reference for the restoration, reconstruction, protection and management of forest in karst hills.

Niche of main woody plant populations of Pterocarya stenoptera community in riparian zone of Lijiang River, China.

To understand the niche characteristics of main woody species in Pterocarya stenoptera community, we investigated P. stenoptera communities in riparian zone of Lijiang River, China. The niche characteristics of main species in tree layers and shrub layers were quantified with the indices of Levins niche breadth, Shannon niche breadth, Schoener niche similarities and Pianka niche overlap. The results showed that P. stenoptera in the tree layer, and Ficus abelii and Morus alba in the shrub layer had higher niche breadth than other species. The species with larger importance values generally had larger niche breadth, but the rank orders of which were not exactly the same. The niche similarity of main populations in the tree layer was generally smaller than that in the shrub layer. The mean value of niche similarity of main populations in the tree layer and shrub layer was 0.151 and 0.236, respectively. There was a low degree of niche similarity among species within the community, indicating that they had a low similarity in resource use. The niche overlap of main populations in the tree layer was generally smaller than that in the shrub layer, with the mean value of niche overlap of main populations in the tree layer and shrub layer being 0.217 and 0.273, respectively. The niche overlap between the main species in the community was relatively lower. There was no significant correlation between niche breadth and niche similarity. The species with larger niche breadth often had more opportunities to overlap with other species. However, their overlap value was not necessarily larger. Larger niche similarity was often associated with higher degrees of niche overlap. The P. stenoptera community in riparian zone of Lijiang River was the climax community, the relationship among species was relatively stable, the population regeneration was very slow, and the development trend of this community was declining in the future.

[Study on mechanism of biminne in treating allergic rhinitis].

OBJECTIVE: To investigate the effect and mechanism of Biminne, a Chinese herbal compound preparation, for treatment of allergic rhinitis (AR). METHODS: AR model of mouse was induced by intraperitoneal injection of ovalbumin (OVA), and the changes in behavior, proliferative activity of splenic lymphocyte, serum levels of total IgE and OVA specific IgE were observed. RESULTS: Biminne showed effects in reducing the frequency of sneezing and nasal rubbing, inhibiting the proliferation of splenic lymphocyte stimulated by phyto-hemagglutinin (PHA) and OVA, and lowering the levels of serum total IgE and OVA specific IgE. CONCLUSION: Biminne could inhibit the proliferation of splenic lymphocyte and reduce serum level of IgE in mice with AR.