Environmental resource deficit may drive the evolution of intraspecific trait variation in invasive plant populations

Intraspecific trait variation within natural populations (i.e. intra‐population trait variation, IPTV) is the basic source for selection and can have significant ecological consequences. Higher IPTV may increase a population's niche breath and benefit interspecies competition under a resource‐limited environment, thus affecting the ability of a species to move into novel habitats. However, the reciprocal influences of variation in environmental conditions and phenotypic trait expression in spreading plant populations are not clearly defined. We propose that during invasion, IPTV and its relative change in response to key resource enrichment may increase with the resource deficit of invaded sites, and that this relationship may facilitate plant invasions into resource‐limited environments. We analyzed the invasion trend, IPTV and its response to water enrichment, and moisture variability among populations of an annual grass Brachypodium hybridum in California, United States. We incorporated a genotyping‐by‐sequencing approach, a common garden experiment that had two water level treatments, and public plant and climate databases. Our hypothesis was supported by the observation that for populations that invaded sites with higher spring moisture deficit, both their seed biomass IPTV (for the water‐enriched treatment only) and relative change of the IPTV across water treatments were larger when examined in the common garden experiment. A generally north to south spreading direction was found in these B. hybridum populations, towards a drier and warmer climate exhibiting higher moisture deficit for plant growth. Our results suggest a role for interactions between IPTV (rather than trait means) and environmental resource availability in promoting plant invasions, providing new insights into the significance of IPTV in shaping plant geographic distributions.     

Interleukin-2 induces extracellular matrix synthesis and TGF-β2 expression in retinal pigment epithelial cells

Macular fibrosis is a vital obstacle of vision acuity improvement of age-related macular degeneration patients. This study was to investigate the effects of interleukin 2 (IL-2) on epithelial-mesenchymal transition (EMT), extracellular matrix (ECM) synthesis and transforming growth factor β2 (TGF-β2) expression in retinal pigment epithelial (RPE) cells. 10 μg/L IL-2 was used to induce fibrosis in RPE cells for various times. Western blot was used to detect the EMT marker α-smooth muscle actin (α-SMA), ECM markers fibronectin (Fn) and type 1 collagen (COL-1), TGF-β2, and the activation of the JAK/STAT3 and NF-κB signaling pathway. Furthermore, JAK/STAT3 and NF-κB signaling pathways were specifically blocked by WP1066 or BAY11-7082, respectively, and the expression of α-SMA, COL-1, Fn and TGF-β2 protein were detected. Wound healing and Transwell assays were used to measure cell migration ability of IL-2 with or without WP1066 or BAY11-7082. After induction of IL-2, the expressions of Fn, COL-1, TGF-β2 protein were significantly increased, and this effect was correlated with IL-2 treatment duration, while α-SMA protein expression did not change significantly. Both WP1066 and BAY11-7082 could effectively downregulate the expression of Fn, COL-1 and TGF-β2 induced by IL-2. What's more, both NF-κB and JAK/STAT3 inhibitors could suppress the activation of the other signaling pathway. Additionally, JAK/STAT3 inhibitor WP1066 and NF-κB inhibitor BAY 11-7082 could obviously decrease RPE cells migration capability induced by IL-2. IL-2 promotes cell migration, ECM synthesis and TGF-β2 expression in RPE cells via JAK/STAT3 and NF-κB signaling pathways, which may play an important role in proliferative vitreoretinopathy.     

Superovulatory response of ovarian follicles of Wave 1 versus Wave 2 in heifers

Experiments were designed to test the hypotheses that ovarian follicular response to superstimulatory treatment initiated during Wave 1 is equivalent to that of Wave 2, and recovery rate and quality of ova embryos derived from follicles of Wave 1 are equivalent to those derived from follicles of Wave 2. In a preliminary experiment (Experiment 1), heifers were given Folltropin-V (20 mg NIH-FSH-P1, im, bid for 5 d) beginning the day after emergence of the first (n=10) or second (n=10) follicular wave of the estrous cycle, equivalent to approximately Day 1 and Day 10, respectively (Day 0=ovulation). Luteolysis was induced with cloprostenol (500 mug im, bid) on the fourth day of treatment. Fewer (P<0.05) ovulations per heifer were induced in the Wave 1 group than in the Wave 2 group (4.6+/-1.0 vs 9.1+/-1.3). However, the interval from wave emergence to initiation of treatment was found, in retrospect, to have been longer (P<0.05) in the Wave 1 group, i.e., treatment was initiated relatively later with respect to wave emergence. Experiment 2 was designed to correct this disparity and to initiate the same treatment protocol on the day of wave emergence rather than the day after (n=21 per Wave group). There was no difference between Wave 1 and Wave 2 groups in the interval from wave emergence to initiation of treatment (0.4+/-0.1 d), the number of ovulations detected by ultrasonography (6.6+/-1.0 vs 8.2+/-1.7), the number of CL detected at slaughter (6.5+/-0.9 vs 8.1+/-1.8), the total number of ova embryos recovered (5.2+/-0.7 vs 5.1+/-0.8), or the number of fertilized embryos collected (2.8+/-0.6 vs 3.0+/-0.6). In addition, there was no difference between groups in the proportion of heifers that ovulated in either experiment; collectively, luteolysis and ovulation was induced in 58 of 60 heifers. The results supported the general hypothesis that follicles and oocytes of the first and second follicular waves are equivalent in the response to superstimulatory treatment. Regardless of which follicular wave, initiation of treatment near the time of wave emergence appears critical for maximal superovulatory response. Because of the consistency in the time of emergence of Wave 1 (day of ovulation) and equivalence in superovulatory response, use of Wave 1 rather than subsequent follicular waves may be more convenient and time-sparing in superovulation programs; the day of estrus (day before ovulation) may be used as a consistent point of reference for the start of treatment.     

(+)-Borneol suppresses conditioned fear recall and anxiety-like behaviors in mice

Fear- and anxiety-related psychiatric disorders have been one of the major chronic diseases afflicting patients for decades, and new compounds for treating such disorders remain to be developed. (+)-Borneol, a bicyclic monoterpene found in several species of Artemisia and Dipterocarpaceae, is widely used for anxiety, pain and anesthesia in Chinese medicine. Meanwhile, it can potentiate GABA (γ-aminobutyric acid) activity directly in recombinant GABAA receptors. The present study was to investigate the effects of (+)-Borneol on both contextual and cued fear recall. Interestingly, microinjection of (+)-Borneol into the dorsal hippocampus inhibited 24 h and 7 d contextual fear, whereas its infusion into ventral hippocampus only reduced 24 h cued fear responses. Moreover, microinjection of (+)-Borneol into dorsal but not ventral hippocampus suppressed anxiety-like behaviors in the open field test, light/dark exploration and the elevated plus maze test. As selective GABA_A receptor antagonist bicuculline reversed the effect of (+)-Borneol on contextual fear paradigm and the drug potentiated GABA-evoked currents in acute hippocampus slices, modulation of the GABAergic neurotransmission may explain the effects of (+)-Borneol. Our findings suggest that (+)-Borneol can serve as a new therapeutic in fear- and anxiety-related disorders.     

Toxins of Pseudomonas syringae pv. syringae affect H+-transport across the plasma membrane of maize

The activity of some phytotoxic metabolites of Pseudomonas syringae pv. syringae Van Hall strains B359 and B301 on in vivo and in vitro systems of H⁺-transport across the plasma membrane of maize (Zea mays L., hybrid Paolo) was investigated. In particular syringomycin, the first lipodepsinonapeptide isolated from Pss and already studied in plants and yeasts for its effects on several physiological systems, was compared with the recently described lipodepsipeptides with 22 or 25 amino acid residues, so called syringopeptins. The in vivo activity of the phytotoxins was tested on fusicoccin-stimulated H^?-extrusion from cuttings of maize roots, which was inhibited by both types of toxins, with syringomycin more efficient than the syringopeptins. In vitro the H⁺-ATPase activity of predominantly right-side-out plasma membrane vesicles purified by two-phase partitioning was stimulated by 10 μM syringomycin and inhibited by higher levels, in agreement with the results of others with preparations of dicotyledons. Also the inhibition of the phosphohydrolytic activity of inside-out vesicles of mung bean plasma membrane was confirmed for maize. In both types of vesicles the syringopeptirts were better inhibitors than syringomycin. The pH gradient formed on addition of ATP to predominantly (25% latency) inside-out vesicles was immediately and completely collapsed by syringomycin and syringopeptins; H⁺-pumping was prevented if the toxins were added before ATP. The inhibition was concentration dependent, but at very low concentrations the effect was inverted. The results of the present investigation, carried out with maize preparations, confirm and extend the evidence so far obtained with dicotyledons in favour of the plasma membrane as an important site of interaction of syringomycin with the plant cell. They also indicate that, except for some details, the effects of syringopeptins at the level of the plasma membrane are the same as those of syringomycin.     

重组人IL6／2融合蛋白对6.5Gy照射小鼠造血功能恢复的影响

观察了ｈＦＰＩＬ６／２对６．５Ｇｙγ线照射ＮＩＨ小鼠第１０天造血功能恢复的影响。结果表明：照射小鼠连续４ｄ给予ｈＦＰＩＬ６／２２５０μｇ·ｋｇ－１·ｄ－１,其脾重、ＣＦＵ－８、骨髓有核细胞数及ＣＭ－ＣＦＵ分别比对照组增加５９．０％、２７８．５％、５７．９％和１３８．２％,统计学处理均有显著差异;对此四项指标的改善也明显优于２５μｇ组。另外,２５０μｇ剂量组小鼠外周血象３０ｄ的动态观察结果表明,ｈＦＰＩＬ６／２不但能明显提高红细胞和血红蛋白的最低值,而且能使血小板的恢复提前。提示ｈＦＰＩＬ６／２在促进血小板生成和促进红系造血方面可能具有良好的应用前景。