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71.
Jun Zhang Kevin A. Fengler John L. Van Hemert Rajeev Gupta Nick Mongar Jindong Sun William B. Allen Yang Wang Benjamin Weers Hua Mo Renee Lafitte Zhenglin Hou Angela Bryant Farag Ibraheem Jennifer Arp Kankshita Swaminathan Stephen P. Moose Bailin Li Bo Shen 《Plant biotechnology journal》2019,17(12):2272-2285
72.
J. Shi Y.‐B. Luo P. Bernhardt J.‐C. Ran Z.‐J. Liu Q. Zhou 《Plant biology (Stuttgart, Germany)》2009,11(1):17-28
Paphiopedilum barbigerum T. Tang et F. T. Wang, a slipper orchid native to southwest China and northern Vietnam, produces deceptive flowers that are self‐compatible but incapable of mechanical self‐pollination (autogamy). The flowers are visited by females of Allograpta javana and Episyrphus balteatus (Syrphidae) that disperse the orchid’s massulate pollen onto the receptive stigmas. Measurements of insect bodies and floral architecture show that the physical dimensions of these two fly species correlate with the relative positions of the receptive stigma and dehiscent anthers of P. barbigerum. These hoverflies land on the slippery centralised wart located on the shiny yellow staminode and then fall backwards through the labellum entrance. They are temporarily trapped in the inflated chamber composed of the interconnected labellum and column. The attractive staminode of P. barbigerum strongly reflects the colour yellow (500–560 nm), a colour preferred innately by most pollen‐eating members of the Syrphidae. No scent molecules were detected using GC mass spectrometry analysis, showing that the primary attractant in this system is visual, not olfactory. Pollination‐by‐deceit in P. barbigerum is contrasted with its congener, P. dianthum, a brood site mimic that is pollinated by ovipositing females of E. balteatus. As the natural rate of fruit set in P. barbigerum (mean 26.3% pooled over three seasons) is lower than that of P. dianthum (mean 58.5% over two seasons), the evolution of false brood sites in some Paphiopedilum spp. should be selectively advantageous as they may provide an increase in the attention and return rates of dependable pollinators to flowers that always lack a reward. 相似文献
73.
Qi Ye Ming Yan Lin Xu Hou Cao Zhenjiang Li Yong Chen Shuya Li Hanjie Ying 《Biotechnology letters》2009,31(4):537-542
An NADPH-dependent carbonyl reductase (PsCR) gene from Pichia stipitis was cloned. It contains an open reading frame of 849 bp encoding 283 amino acids whose sequence had less than 60% identity
to known reductases that produce ethyl (S)-4-chloro-3-hydroxybutanoates (S-CHBE). When expressed in Escherichia coli, the recombinant PsCR exhibited an activity of 27 U/mg using ethyl 4-chloro-3-oxobutanoate (COBE) as a substrate. Reduction
of COBE to (S)-CHBE by transformants in an aqueous mono-phase system for 18 h, gave a molar yield of 94% and an optical purity of the (S)-isomer of more than 99% enantiomeric excess. 相似文献
74.
Charles Jia-Yin Hou Cheng-Ho Tsai Cheng-Huang Su Yih-Jer Wu Su-Jen Chen Jing-Jing Chiu Ming-Shi Shiao Hung-I Yeh 《The journal of histochemistry and cytochemistry》2008,56(8):745-752
We examined the endothelial gap junctions in diabetic hyperlipidemic mice. Male apolipoprotein E (apoE)-deficient mice were made diabetic by streptozotocin. Three weeks later, the animals were treated with simvastatin for 2 weeks. The expression of aortic gap junctions in the non-diabetic (n=10), untreated diabetic (n=10), and simvastatin-treated diabetic animals (n=6) was analyzed. There was a >4-fold increase in serum cholesterol level and >50% increase in plaque areas in the diabetic mice, regardless of simvastatin treatment. Western blotting of aortae showed reduced expression of connexin37 (Cx37) and Cx40 in the diabetic mice, which were further decreased in the simvastatin-treated diabetic mice. Immunoconfocal microscopy showed that endothelial gap junctions made of Cx37 and Cx40 were both reduced in the untreated diabetic mice compared with the non-diabetic mice (decrease: Cx37, 41%; Cx40, 42%; both p<0.01). The reduction was greater in the simvastatin-treated mice (decrease in treated diabetic vs non-diabetic: Cx37, 61%; Cx40, 79%; both p<0.01; decrease in treated diabetic vs untreated diabetic: Cx37, 34%; Cx40, 63%; both p<0.01). Cx37 and Cx40 were decreased in the endothelium of plaque surface. Cx43 appeared in the medial layer and inner layer of the intima. All three connexins were rarely expressed in monocytes/macrophages inside the plaques. In conclusion, in apoE-deficient mice, streptozotocin-induced diabetes is associated with downregulation of endothelial Cx37 and Cx40 gap junctions. Short-term treatment with simvastatin exacerbates the downregulation. 相似文献
75.
Cui’e Lu Linyu Shi Bei Sun Yu Zhang Bailing Hou Yu’e Sun Zhengliang Ma Xiaoping Gu 《Cellular and molecular neurobiology》2017,37(1):101-109
The objective of this study was to explore the potential role of G-protein-coupled receptor kinase 2 (GRK2) in the progression of cannabinoid 2 receptor (CB2) agonist-induced analgesic effects of bone cancer pain. Female Sprague–Dawley rats, weighing 160–180 g, were utilized to establish a model of bone cancer pain induced by intra-tibia inoculation of Walker 256 mammary gland carcinoma cells. JWH-015, a selective CB2 agonist, was injected intrathecally or intraperitoneally on postoperative day 10. Bone cancer-induced pain behaviors—mechanical allodynia and ambulatory pain—were assessed on postoperative days ?1 (baseline), 4, 7, and 10 and at post-treatment hours 2, 6, 24, 48, and 72. The expressions of spinal CB2 and GRK2 protein were detected by Western Blotting on postoperative days ?1 (baseline), 4, 7, and 10 and at post-treatment hours 6, 24, and 72. The procedure produced prolonged mechanical allodynia, ambulatory pain, and different changes in spinal CB2 and GRK2 expression levels. Intrathecal or intraperitoneal administration of JWH-015 alleviated the induced mechanical allodynia and ambulatory pain, and inhibited the downregulation of spinal GRK2 expression. These effects were in a time-dependent manner and reversed by pretreatment of CB2 selective antagonist AM630. The results affirmed CB2 receptor agonists might serve as new treatment targets for bone cancer pain. Moreover, spinal GRK2 was an important regulator of CB2 receptor agonist-analgesia pathway. 相似文献
76.
In this report, 156 hygromycin-resistant mutants were generated via restriction enzyme-mediated insertional (REMI) mutagenesis. All mutants were subjected to a bioassay on detached leaves. Five mutants (T4, T39, T71, T91, and T135) showed reduced symptom development, whereas one mutant (T120) did not exhibit any symptoms on the leaves compared with the wild type. The pathogenicity of these mutants was further assayed through the spray inoculation of whole seedlings. The results demonstrated that the pathogenicity of the T4, T39, T71, T91, and T135 mutants was reduced, whereas the T120 mutant lost its pathogenicity. Southern blot analysis revealed that the plasmids were inserted at different sites in the genome with different copy numbers. Flanking sequences approximately 550, 860, and 150 bp were obtained from T7, T91, and T120, respectively through plasmids rescue. Sequence analysis of the flanking sequences from T7 and T91 showed no homology to any known sequences in GenBank. The flanking sequence from the T120 mutant was highly homologous to MAPKK kinases, which regulates sexual/asexual development, melanization, pathogenicity from Cochliobolus heterostrophus. These results indicate that REMI and plasmids rescue have great potential for finding pathogenicity genes. 相似文献
77.
L. C. Triarhou E. H. Stotz W. C. Low J. Norton B. Ghetti B. Landwehrmeyer J. M. Palacios J. R. Simon 《Neurochemical research》1994,19(11):1349-1358
The dopamine (DA) uptake system was investigated in the mesostriatal system of normal and weaver mutant mice, which lose mesencephalic DA neurons, as well as in weaver mutants with ventral mesencephalic grafts to the striatum. Assays of [3H]DA uptake in striatal synaptosomal fractions in vitro and autoradiography of [3H]mazindol binding in brain sections were carried out in wild-type mice (+/+) and in the two hemispheres of homozygous weaver mutants (wv/wv) that had received unilateral grafts of mesencephalic cell suspensions to the right side. Net [3H]DA uptake, expressed as pmol/mg-protein/2-min, was on the average 50.6 in the striatum of wild-type mice, 7.9 in the non-grafted, and 10.1 in the transplanted striatum of weaver mutants. [3]DA uptake in wild-type mice differed significantly from both the grafted and non-grafted weaver striata (P<0.001). Paired comparisons for [3H]DA uptake between right and left sides of recipient weaver mice showed a significant side effect (P<0.02), the right side being 28–38% higher than the left side [mean of all individual (R-L)/L values]. The results of amphetamine-induced turning behavior tests were compared with the biochemical findings. Mice with grafts to the right side rotated an average of 22 turns to the left and 7 turns to the right during the five one-minute sessions; the mean value L/(L+R) was 64%. A plot of (L-R) rotations against (R-L) [3H]DA uptake gave a correlation coefficient of 0.552 (P<0.05), indicating that animals with a strong rotational bias to the left tended to have higher [3H]DA on the right. Similarly, the animals that were used for [3H]mazindol binding autoradiographic studies displayed on the average 72% rotations to the left side. In the [3H]mazindol binding data, non-grafted weaver mutants showed the severest depletion relative to wild-type in the dorsomedial and dorsolateral caudate-putamen (86% and 87%, respectively). Mice with unilateral grafts to the right side showed an increase in [3H]mazindol binding signal in the transplanted side of 40–64% (depending on dorsoventral topography) over the contralateral, non-grafted side. These findings attest to the functional effects of the grafts at the anatomical, biochemical, and behavioral levels. The parallel measurements of motor performance and DA uptake in the same animals offers an index of behavioral recovery as a function of transmitter-related activity. Furthermore, by conducting measurements of the synaptosomal DA uptake in vitro and of the binding characteristics of mazindol in brain slices by autoradiography, one has the advantage of combining the anatomical resolution of uptake site visualization with a dynamic indicator of function for DA uptake in the nerve terminal.Special issue dedicated to Professor Sidney Ochs 相似文献
78.
Yuanyuan Yu Lei Hou Xu Shi Xiaoru Sun Xinhui Liu Yifan Yu Zhongshang Yuan Hongkai Li Fuzhong Xue 《PLoS genetics》2022,18(3)
Nonrandom selection in one-sample Mendelian Randomization (MR) results in biased estimates and inflated type I error rates only when the selection effects are sufficiently large. In two-sample MR, the different selection mechanisms in two samples may more seriously affect the causal effect estimation. Firstly, we propose sufficient conditions for causal effect invariance under different selection mechanisms using two-sample MR methods. In the simulation study, we consider 49 possible selection mechanisms in two-sample MR, which depend on genetic variants (G), exposures (X), outcomes (Y) and their combination. We further compare eight pleiotropy-robust methods under different selection mechanisms. Results of simulation reveal that nonrandom selection in sample II has a larger influence on biases and type I error rates than those in sample I. Furthermore, selections depending on X+Y, G+Y, or G+X+Y in sample II lead to larger biases than other selection mechanisms. Notably, when selection depends on Y, bias of causal estimation for non-zero causal effect is larger than that for null causal effect. Especially, the mode based estimate has the largest standard errors among the eight methods. In the absence of pleiotropy, selections depending on Y or G in sample II show nearly unbiased causal effect estimations when the casual effect is null. In the scenarios of balanced pleiotropy, all eight MR methods, especially MR-Egger, demonstrate large biases because the nonrandom selections result in the violation of the Instrument Strength Independent of Direct Effect (InSIDE) assumption. When directional pleiotropy exists, nonrandom selections have a severe impact on the eight MR methods. Application demonstrates that the nonrandom selection in sample II (coronary heart disease patients) can magnify the causal effect estimation of obesity on HbA1c levels. In conclusion, nonrandom selection in two-sample MR exacerbates the bias of causal effect estimation for pleiotropy-robust MR methods. 相似文献
79.
Xia M Hou C Demong D Pollack S Pan M Brackley J Singer M Matheis M Cavender D Wachter M 《Bioorganic & medicinal chemistry letters》2008,18(12):3562-3564
The synthesis and biological evaluation of a series of substituted dipiperidine alcohols are described. Structure-activity relationship studies led to the discovery of potent CCR2 antagonists displaying IC(50) values in the nanomolar or subnanomolar range. The cinnamoyl compounds had higher binding affinities than the corresponding urea analogs. 相似文献
80.
Hye Ran Park Jae Meen Lee Gwanhee Ehm Hui-Jun Yang In Ho Song Yong Hoon Lim Mi-Ryoung Kim Keyoung Ran Kim Woong-Woo Lee Young Eun Kim Jae Ha Hwang Chae Won Shin Hyeyoung Park Jin Wook Kim Han-Joon Kim Cheolyoung Kim Dong Gyu Kim Beom Seok Jeon Sun Ha Paek 《PloS one》2016,11(1)