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531.
Vásquez-Velásquez AI García-Castillo HA González-Mercado MG Dávalos IP Raca G Xu X Dwyer E Rivera H 《Cytogenetic and genome research》2011,132(4):233-238
We report on 2 similarly affected cousins with a compound imbalance resulting from a familial t(5;9)(q34;p23) and entailing both an ~17-Mb 5q terminal duplication and an ~12-Mb 9p terminal deletion as determined by G-banding, subtelomere FISH, and aCGH. The proband's karyotype was 46,XX,der(9)t(5;9)(q34;p23)mat.ish der(9)t(5;9)(q34;p23)(9pter-,5qter+).arr 5q34q35(163,328,000-180,629,000)×3, 9p24p23(194,000-12,664,000)×1. Her cousin had the same unbalanced karyotype inherited from his father. The clinical phenotype mainly consists of a distinct craniofacial dysmorphism featuring microcephaly, flat facies, down slanting palpebral fissures, small flat nose, long philtrum, and small mouth with thin upper lip. Additional remarkable findings were craniosynostosis of several sutures, craniolacunia and preaxial polydactyly in the proband and hypothyroidism in both subjects. The observed clinical constellation generally fits the phenotypic spectrum of the 5q distal duplication syndrome (known also as Hunter-McAlpine syndrome), except for the thyroid insufficiency which can likely be ascribed to the concurrent 9p deletion, as at least 4 other 9pter monosomic patients without chromosome 5 involvement had this hormonal disorder. The present observation further confirms the etiology of the HMS phenotype from gain of the 5q35→qter region, expands the clinical pictures of partial trisomy 5q and monosomy 9p, and provides a comprehensive list of 160 patients with 5q distal duplication. 相似文献
532.
We report here on efforts to show that a combination of native wetland plant species might perform better than a monoculture in wetlands designed for arsenic remediation by supplementing weaknesses. Carex stricta and Spartina pectinata were used in hydroponic experiments. (i) Arsenic uptake was first assessed at two ages via exposure to control or arsenic-laden solutions (0 or 1.5 mg As L(-1) as Na2HAsO4) for two weeks. Age had no significant effect on arsenic concentrations in roots, but translocation factors were greater in older plants of C. stricta and S. pectinata (0.45 and 0.07, respectively) than in younger plants (0.10 and 0.01, respectively). (ii) Seasonal effects were assessed by determining uptake kinetics for both species in conditions representative of spring temperatures (15/5 degrees C) and light regimes (1050 micromol m(-2) s(-1), 13 h day(-1)) and summer temperatures (28/17 degrees C) and light regimes (1300 micromol m(-2) s(-1), 15 h day(-1)). Both species had comparable rates of arsenic uptake into roots in summer conditions (44.0 and 46.5 mg As kg(-1) dry wt. h(-1) in C. stricta and S. pectinata, respectively), but C. stricta had a higher maximum net influx rate in spring conditions (24.5 versus 10.4 mg As kg(-1) dry wt. h(-1)). 相似文献
533.
Künzli BM Bernlochner MI Rath S Käser S Csizmadia E Enjyoji K Cowan P d'Apice A Dwyer K Rosenberg R Perren A Friess H Maurer CA Robson SC 《Purinergic signalling》2011,7(2):231-241
Despite improvements in prevention and management of colorectal cancer (CRC), uncontrolled tumor growth with metastatic spread to distant organs remains an important clinical concern. Genetic deletion of CD39, the dominant vascular and immune cell ectonucleotidase, has been shown to delay tumor growth and blunt angiogenesis in mouse models of melanoma, lung and colonic malignancy. Here, we tested the influence of CD39 on CRC tumor progression and metastasis by investigating orthotopic transplanted and metastatic cancer models in wild-type BALB/c, human CD39 transgenic and CD39 deficient mice. We also investigated CD39 and P2 receptor expression patterns in human CRC biopsies. Murine CD39 was expressed by endothelium, stromal and mononuclear cells infiltrating the experimental MC-26 tumors. In the primary CRC model, volumes of tumors in the subserosa of the colon and/or rectum did not differ amongst the treatment groups at day 10, albeit these tumors rarely metastasized to the liver. In the dissemination model, MC-26 cell line-derived hepatic metastases grew significantly faster in CD39 over-expressing transgenics, when compared to CD39 deficient mice. Murine P2Y2 was significantly elevated at both mRNA and protein levels, within the larger liver metastases obtained from CD39 transgenic mice where changes in P2X7 levels were also noted. In clinical samples, lower levels of CD39 mRNA in malignant CRC tissues appeared associated with longer duration of survival and could be linked to less invasive tumors. The modulatory effects of CD39 on tumor dissemination and differential levels of CD39, P2Y2 and P2X7 expression in tumors suggest involvement of purinergic signalling in these processes. Our studies also suggest potential roles for purinergic-based therapies in clinical CRC. 相似文献
534.
CJ Cooksey 《Biotechnic & histochemistry》2013,88(2):105-125
This bibliography lists and comments on publications describing the history, preparation, chemistry and some applications of indigo and related dyes. Note that the commentary by the author is in italics after the bibliographic information. 相似文献
535.
Polymerase chain reaction (PCR) gut analysis was conducted on specimens of the introduced spider Tenuiphantes tenuis collected from dairy pasture in Canterbury, New Zealand. PCR primers were specifically designed to amplify a fragment of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) from Listronotus bonariensis and revealed that this major pasture pest species is consumed in the field by T. tenuis. The field predation rate of L. bonariensis by T. tenuis was estimated from our PCR results together with published data on the degradation of DNA and the density of T. tenuis in Canterbury pastures. We found that T. tenuis is a potentially significant predator of L. bonariensis in New Zealand pastures. 相似文献
536.
Population consequences of constitutive and inducible plant resistance: herbivore spatial spread 总被引:2,自引:0,他引:2
Abstract Little attention has been paid to the impact that constitutive and inducible plant resistance traits will have on herbivore spatial dynamics. We investigate mathematical models in which herbivore demographic rates and movement rates respond to host plant quality, which in turn is determined by constitutive and inducible resistance. Models with and without induced resistance yield the same analytic expression for the asymptotic speed at which a herbivore population will spread through an initially uninduced plant population, suggesting that induced resistance will have no effect on the rate of invasion of herbivores that respond to plant resistance on small spatial scales. In contrast, constitutive resistance will influence the speed of an invasion. If herbivore movement is quite sensitive to plant quality, an increase in constitutive resistance can actually accelerate the rate of herbivore spread even while it reduces the herbivore's intrinsic rate of increase. In other scenarios, the rate of invasion attains a maximum at intermediate levels of constitutive resistance. These results argue that our view of plant resistance should be broadened to include herbivore movement if we are to understand fully the implications of differences in resistance for the dynamics of herbivore populations in natural and managed settings. 相似文献
537.
Thinning is thought to be particularly effective at accelerating plant community recovery in some dense regenerating forests where one species dominates. However, longer‐term experimental data are required to confirm the efficacy of thinning for this purpose. We investigated plant community responses 8 years after thinning in densely resprouting brigalow (Acacia harpophylla) forests in Australia. We examined the abundance, diversity, composition, and size of all woody recruits, as well as the functional composition of woody plant assemblages using functional traits. The average prethinning density of A. harpophylla was 15,600 stems/ha. Four treatments were applied to 25 × 25 m plots in a randomized block design: control (no thinning) and random thinning (ringbarking) down to 4,000, 2,000, and 1,000 stems/ha. Reference plots were also established in a nearby mature forest. Thinning accelerated the recruitment of certain shrub species and increased some measures of diversity. However severe thinning led to an overabundance of exploitative shrub species (high‐specific leaf area and low stem‐specific density), akin to pioneer dominance during early stages of rainforest succession. Species with more conservative growth strategies have so far failed to recruit, potentially due to dispersal limitation. Longer‐term monitoring is required to determine if thinning does in fact accelerate compositional recovery in this endangered Australian ecosystem. 相似文献
538.
Anilkumar G. Nair Qingbei Zeng Oleg Selyutin Stuart B. Rosenblum Yueheng Jiang De-Yi Yang Kerry Keertikar Guowei Zhou Michael Dwyer Seong Heon Kim Bandarpalle Shankar Wensheng Yu Ling Tong Lei Chen Robert Mazzola John Caldwell Haiqun Tang Sony Agrawal Joseph A. Kozlowski 《Bioorganic & medicinal chemistry letters》2018,28(10):1954-1957
HCV NS5A inhibitors have shown impressive in vitro potency profiles in HCV replicon assays thus making them attractive components for inclusion in an all oral fixed dose combination regimen. Herein, we describe the discovery and characterization of silyl proline-containing HCV NS5A inhibitor MK-8325 with good pan-genotype activity and acceptable pharmacokinetic properties. 相似文献
539.
540.
Extracellular ATP interacts with purinergic type 2 (P2) receptors and elicits many crucial biological functions. Extracellular ATP is sequentially hydrolyzed to ADP and AMP by the actions of defined nucleotidases, such as CD39, and AMP is converted to adenosine, largely by CD73, an ecto-5′-nucleotidase. Extracellular adenosine interacts with P1 receptors and often opposes the effects of P2 receptor activation. The balance between extracellular ATP and adenosine in the blood and extracellular fluid is regulated chiefly by the activities of CD39 and CD73, which constitute the CD39-adenosinergic axis. In recent years, several studies have shown this axis to play critical roles in transport of water/sodium, tubuloglomerular feedback, renin secretion, ischemia reperfusion injury, renal fibrosis, hypertension, diabetic nephropathy, transplantation, inflammation, and macrophage transformation. Important developments include global and targeted gene knockout and/or transgenic mouse models of CD39 or CD73, biological or small molecule inhibitors, and soluble engineered ectonucleotidases to directly impact the CD39-adenosinergic axis. This review presents a comprehensive picture of the multiple roles of CD39-adenosinergic axis in renal physiology, pathophysiology, and therapeutics. Scientific advances and greater understanding of the role of this axis in the kidney, in both health and illness, will direct development of innovative therapies for renal diseases. 相似文献