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61.
The class II phosphoinositide 3-kinase C2beta is not essential for epidermal differentiation 下载免费PDF全文
Phosphoinositide 3-kinases (PI3Ks) regulate an array of cellular processes and are comprised of three classes. Class I PI3Ks include the well-studied agonist-sensitive p110 isoforms; however, the functions of class II and III PI3Ks are less well characterized. Of the three class II PI3Ks, C2alpha and C2beta are widely expressed in many tissues, including the epidermis, while C2gamma is confined to the liver. In contrast to the class I PI3K p110alpha, which is expressed throughout the epidermis, C2beta was found to be localized in suprabasal cells, suggesting a potential role for C2beta in epidermal differentiation. Overexpressing C2beta in epidermal cells in vitro induced differentiation markers. To study a role for C2beta in tissue, we generated transgenic mice overexpressing C2beta in both suprabasal and basal epidermal layers. These mice lacked epidermal abnormalities. Mice deficient in C2beta were then generated by targeted gene deletion. C2beta knockout mice were viable and fertile and displayed normal epidermal growth, differentiation, barrier function, and wound healing. To exclude compensation by C2alpha, RNA interference was then used to knock down both C2alpha and C2beta in epidermal cells simultaneously. Induction of differentiation markers was unaffected in the absence of C2alpha and C2beta. These findings indicate that class II PI3Ks are not essential for epidermal differentiation. 相似文献
62.
Innate immunity is critical for sensing and defending against microbial infections in multicellular organisms. In plants, disease resistance genes (R genes) play central roles in recognizing pathogens and initiating downstream defense cascades. Arabidopsis SNC1 encodes a TIR-NBS-LRR-type R protein with a similar structure to nucleotide binding oligomerization domain (Nod) proteins in animals. A point mutation in the region between the NBS and LRR of SNC1 results in constitutive activation of defense responses in the snc1 mutant. Here, we report the identification and characterization of mos2-1, a mutant suppressing the constitutive defense responses in snc1. Analysis of mos2 single mutants indicated that it is not only required for resistance specified by multiple R genes, but also for basal resistance. Map-based cloning of MOS2 revealed that it encodes a novel nuclear protein that contains one G-patch and two KOW domains and has homologs across the animal kingdom. The presence of both G-patch and KOW domains in the MOS2 protein suggests that it probably functions as an RNA binding protein critical for plant innate immunity. Our discovery on the biological functions of MOS2 will shed light on functions of the MOS2 homologs in animals, where they may also play important roles in innate immunity. 相似文献
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Strenja-Linić I Vojniković B Caljkusić-Mance T Tićac R Bonifacić D Kovacević D 《Collegium antropologicum》2010,34(Z2):49-52
Carotid artery stenosis (CAS) is one of the major complications of external irradiation (radiotherapy, RT) for laryngeal carcinoma. Considering amaurosis fugax is often one of the first signs of significant CAS our focus was to determine weather patients with post-irradiation CAS also develop ocular microangiopathy as a result of insufficient ophthalmic circulation. In our study Carotid Duplex ultrasound scans revealed that 33.33% of patients had significant radiation-induced CAS. The majority (over 85.71%) of radiation-induced CAS had more than one atherosclerotic plaque including any degree of stenosis in the RT group, and had significantly more than that of the control group. Microangiopathic changes were documented only with the patients that have had an increased cerebrovascular risk (diabetes mellitus and arterial hypertension). 相似文献
66.
Enhanced somatic embryogenesis and plant regeneration have been obtained using young leaf bases of naked oat (Avena nuda) as explants by including salicylic acid (SA) and carrot embryogenic callus extracts (CECE) in media. A 5- and 4-fold improvement
was achieved in somatic embryogenesis and plant regeneration on the corresponding media supplemented with 0.5 mM SA and CECE
as compared to control, respectively. Some physiological and biochemical changes were assayed in both embryogenic callus (EC)
and non-embryogenic callus (NEC). The results indicated that superoxide dismutase activity was stimulated and catalases and
ascorbate peroxidase activities were inhibited, while the O2
- (superoxide anion) content was reduced and the hydrogen peroxide level was promoted in EC compared with NEC. Reduced malondialdehyde
content and relative electrolyte leakage were also detected in EC. 相似文献
67.
Twenty percent of 1000 dairy cows were infected with Trichophyton verrucosum in a newly established dairy farm in western China. The disease was transmitted to 30 of 100 animal workers. The source of the outbreak is unknown but it is suspected that naïve cattle which were transported from Holland to China became infected after they arrived in Xinjiang province (West China) where the fungus is endemic in nature, prepuberty school children and various livestock. 相似文献
68.
In this study, two isomeric ruthenium(II) complexes [Ru(bpy)(2)(p-mopip)](2+) (1) and [Ru(bpy)(2)(o-mopip)](2+) (2) (bpy = 2, 2-bipyridine; L: p-mopip = 2-(4-methoxylphenyl) imidazo [4,5-f][1,10]phenanthroline, o-mopip = 2-(2-methoxylphenyl) imidazo[4,5-f][1,10] phenan-throline) contained -OCH(3) at different positions on the phenyl ring and their enantiomers Λ-1, -2 and Δ-1, -2 displayed different properties. The cell viability of these ruthenium(II) complexes was evaluated by MTT, and complex Λ-1 has shown significant higher anticancer potency than Δ-1 against all the cell lines screened. Fluorescence microscopy and flow cytometric analyses demonstrated that complex Λ-1 was able to induce apoptosis. The interactions of complexes Λ-1, 1, and Δ-1 with bovine serum albumin (BSA) were investigated by fluorescence and circular dichroism (CD) measurements. The fluorescence quenching mechanism of BSA by complexes Λ-1, 1, and Δ-1 was determined to be a static process, and the apparent binding constant K(a) values is as follows: Λ-1 >1 > Δ-1. The number of binding sites n for all these complexes was 1. The result of CD showed that the secondary structure of BSA molecules was changed in the presence of the ruthenium(II) complex. 相似文献
69.
The present study evaluated nitrogen (N) input and output in mainland China using updated data of temporally and spatially-based land use maps and statistical data at national and provincial scales. The total N inputs increased from 3,081 kg km?2 in 1985 to 5,426 kg km?2 in 2007. Chemical fertilizer dominated the N input and showed an increasing trend. Biological N fixation was the second important N input till 1990 and atmospheric deposition became the second most important source after that, accounting for 24.0% in 2007. There was no net N input through food/feed import in 1985, but it accounted for 3.5% of the total N input in 2007. According to a mass balance model, we assumed total N input equal to output. The results showed that more than half of the total N was denitrified or stored in the system. Ammonia volatilization accounted for 18.9–22.9% of the total N input, and N export to water bodies accounted for 17.9–20.7%. About 5.1–7.7% of the N input was emitted to the atmosphere through biomass burning. When calculated per unit area, total N input, N export to water bodies, denitrification and storage could be very well explained by human population density. Nitrogen input and major outputs were also positively related to per capita gross domestic product and the percentage of total land area used as cropland. The N budget is compared to that of some other countries and the environmental impacts of the N cycle is discussed. 相似文献
70.
The population dynamics parameters of scaldfish, Arnoglossus laterna, from the Adriatic Sea were studied. Specimens ranging from 4.5 to 17.1 cm in total length were collected from commercial bottom‐trawl catches (2000–2006). Spawning from April through the end of August with a peak in May, A. laterna is one of the non‐target species usually present in mixed bottom trawl catches. The overall male to female ratio was 1.00 : 0.61. The oldest individual was 6 years of age. Length–weight relationships showed positive allometric growth (b = 3.36 for males and b = 3.39 for females). Parameters of the von Bertalanffy growth equation were: L∞ = 17.3 cm; K = 0.258 per year; t0 = ?1.0026 year; R2 = 0.925. The relatively low value of total mortality (Z = 0.90) and relatively high value of constant rate of natural mortality (M = 0.64) was estimated. Presumed calculated fishing mortality (F = 0.26) and the consequently estimated exploitation ratio (E = 0.29) indicated no danger of an over‐exploitation of this species in the study area at the current level of fishing pressure. The low T max and correspondingly high M suggest that this small benthic predator plays an important role in the Adriatic ecosystem as a prey species for large benthic predators. However, the estimates include uncertainties and require further confirmation, especially with regard to natural mortality. 相似文献