43 research outputs found
Plastid structure and carotenogenic gene expression in red- and white-fleshed loquat (Eriobotrya japonica) fruits
Loquat (Eriobotrya japonica Lindl.) can be sorted into red- and white-fleshed cultivars. The flesh of Luoyangqing (LYQ, red-fleshed) appears red-orange because of a high content of carotenoids while the flesh of Baisha (BS, white-fleshed) appears ivory white due to a lack of carotenoid accumulation. The carotenoid content in the peel and flesh of LYQ was approximately 68 μg g−1 and 13 μg g−1 fresh weight (FW), respectively, and for BS 19 μg g−1 and 0.27 μg g−1 FW. The mRNA levels of 15 carotenogenesis-related genes were analysed during fruit development and ripening. After the breaker stage (S4), the mRNA levels of phytoene synthase 1 (PSY1) and chromoplast-specific lycopene β-cyclase (CYCB) were higher in the peel, and CYCB and β-carotene hydroxylase (BCH) mRNAs were higher in the flesh of LYQ, compared with BS. Plastid morphogenesis during fruit ripening was also studied. The ultrastructure of plastids in the peel of BS changed less than in LYQ during fruit development. Two different chromoplast shapes were observed in the cells of LYQ peel and flesh at the fully ripe stage. Carotenoids were incorporated in the globules in chromoplasts of LYQ and BS peel but were in a crystalline form in the chromoplasts of LYQ flesh. However, no chromoplast structure was found in the cells of fully ripe BS fruit flesh. The mRNA level of plastid lipid-associated protein (PAP) in the peel and flesh of LYQ was over five times higher than in BS peel and flesh. In conclusion, the lower carotenoid content in BS fruit was associated with the lower mRNA levels of PSY1, CYCB, and BCH; however, the failure to develop normal chromoplasts in BS flesh is the most convincing explanation for the lack of carotenoid accumulation. The expression of PAP was well correlated with chromoplast numbers and carotenoid accumulation, suggesting its possible role in chromoplast biogenesis or interconversion of loquat fruit
Formation Mechanism for the TiN-MnS Complex Inclusions in Tire Cord Steel
High strength tire cord steel is extensively used in radial ply tyres as the framework material, but the presence of brittle single titanium inclusions or complex titanium inclusions can cause failure of the wires and jeopardize their performance in production. In order to provide a key guidance on the control of titanium inclusions, it is necessary to clarify their formation mechanism during solidification. In the present work, the thermodynamic calculations were employed for an elaboration on their formation mechanism, combined with the industrial test. The TiN-MnS complex inclusions observed by SEM-EDS shows that the internal corresponds to TiN and the external is MnS. Thermodynamic calculations based on the microsegregation model indicate that MnS forms first, which can act as a nucleation site for the co-deposit of TiN in the mushy zone. As the MnS inclusions have a better deformation than that of TiN inclusions, then the TiN inclusions are wrapped by the MnS inclusions, generating TiN-MnS complex inclusions after rolling
Focusing of linearly polarized Lorentz–Gauss beam with one optical vortex
Focusing properties of linearly polarized Lorentz–Gauss beam with one on-axis optical vortex was investigated by vector diffraction theory. Results show that the focal pattern can be altered considerably by charge number of the optical vortex and the beam parameters. Many novel focal patterns may occur, such as dark hollow focus, multiple-peak focal pattern, and dark hollow focus chain. For certain beam parameter, the focal pattern changes more remarkably in the direction perpendicular to the incident polarized direction than that in polarized direction. Especially, there is one clear relation between the intensity distributions along the direction perpendicular to the polarized direction and the charge number of the optical vortex, which may be used as one measurement method of charge number
Rab11a Is Overexpressed in Gastric Cancer and Regulates FAK/AKT Signaling
Dysregulation of Rab11a has been implicated in the progression of several cancers. However, there have been no such studies for human gastric cancers. In the current study, we examined Rab11a protein expression and found it was upregulated in 49 of 108 gastric cancer tissues and correlated with local invasion, nodal metastasis, and advanced stage. Rab11a protein was higher in gastric cancer cell lines than normal gastric cell line. We transfected Rab11a plasmid and siRNA in both MGC803 and AGS cell lines. Rab11a overexpression increased the cell growth rate, colony numbers, and invasion ability in both MGC803 and AGS cell lines. Downregulation of Rab11a using siRNA decreased the cell proliferation rate, colony numbers, and inhibited invasion. Rab11a overexpression also conferred cisplatin resistance. Annexin V/PI staining showed that Rab11a overexpression suppressed cisplatin-induced apoptosis, while Rab11a depletion promoted cell apoptosis. We also showed that Rab11a overexpression maintained mitochondrial membrane potential. Western blot analysis revealed that Rab11a increased protein expression of MMP2, cyclin D1, Bcl-2, p-FAK, and p-AKT, while Rab11a depletion showed the opposite effects. Blockage of FAK using inhibitor downregulated Bcl-2, cyclin D1, MMP2, and p-AKT expression and abolished the effects of Rab11a on these proteins. In summary, our data demonstrated that Rab11a is upregulated in human gastric cancers. Rab11a facilitated cell proliferation and invasion, as well as cisplatin sensitivity and mitochondrial membrane potential, possibly via the FAK/AKT signaling pathway
Recent Advances in the Emission and Functions of Plant Vegetative Volatiles
Plants synthesize and emit a large variety of volatile organic compounds, which possess extremely important ecological functions. In most case, most plant volatiles are liquids, rather than gases, at room temperature. Some volatiles are emitted “on demand” when plants, especially vegetative parts, are exposed to abiotic or biotic stress. In this review, we summarize some of the highlights of plant vegetative volatile emission and functions research published during the past few years
A Chinese Girl with Bartter Syndrome Type III due to a Novel Mutation and/or Single Nucleotide Polymorphisms (SNPs) in CLCNKB Gene
Background: Bartter’s syndrome is a heterogeneous disorder
characterized by deficient renal reabsorption of sodium and chloride,
and hypokalemic metabolic alkalosis with hyper-reninemia and
hyperaldosteronemia. Bartter syndrome type III (BS type III), due to
mutations in the CLCNKB gene, is highly variable. The aim of our study
was to describe the clinical presentation in a Chinese girl with BS
type III and to explore mutations or SNPs of CLCNKB gene in her family.
Case Presentation: The clinic data of the patient was collected.
Mutations or SNPs were investigated by sequencing of the exon of CLCNKB
gene. The clinic analysis confirmed the diagnosis of BS type III. The
coexistence of 13 reported SNPs and 11 novel SNPs of CLCNKB gene were
found in the patient and her parent. a novel heterozygous C to G
transition at nucleotide 2471 in exon 20 of CLCNKB gene harbored
uniquely by the patient were revealed. Conclusion: A novel heterozygous
C to G mutation at nucleotide 2471 of CLCNKB gene and some new SNPs
were identified in a Chinese girl with BS type III having persistent
hypokalemia. The novel mutation and SNPs make the genetic background of
the patient more complicated
Focus shaping of linearly polarized Lorentz beam with sine-azimuthal variation wavefront
Focal shaping plays an important role in many optical focusing systems. In this paper, the focusing properties of linearly polarized Lorentz beam with sine-azimuthal variation wavefront were investigated. Simulation results show that the focal pattern can be altered considerably by the beam parameters and the phase parameter that indicates the phase change frequency on increasing azimuthal angle. And some novel focus shape may appear, including multiple-peak focal pattern, wheel focal pattern. And some optical gradient force distributions were also given to show that the focusing properties of this kind of Lorentz beams may be used to construct tunable optical traps, which may pave the way for application of laser diode in tweezers technique
Defect-Related Etch Pits on Crystals and Their Utilization
Etch pits could form on an exposed surface of a crystal when the crystal is exposed to an etching environment or chemicals. Due to different dissolution rates along various crystalline directions in a crystal, the dissolution process is anisotropic; hence, etch pits usually have a regular shape. Here, the morphology and origin of the regular-shaped etch pits are discussed firstly; then, factors which could affect the morphology and density of etch pits are shown; finally, the state of the art of etch pit technology and the utilization of etch pits is presented. Traditionally, etch pits are utilized to evaluate the dislocation density and some defect-related properties. Now, in the modern fabrication industries, the relationship between etch pits and defects has been utilized more skillfully. High-quality crystals can be fabricated by controlling dislocations revealed by etch pits. Meanwhile, with the as-revealed dislocation as the diffusion path of atoms, new crystals will emerge in corresponding etch pits
Microscopic Analyses of Fruit Cell Plastid Development in Loquat (<i>Eriobotrya japonica</i>) during Fruit Ripening
Plastids are sites for carotenoid biosynthesis and accumulation, but detailed information on fruit plastid development and its relation to carotenoid accumulation remains largely unclear. Here, using Baisha (BS; white-fleshed) and Luoyangqing (LYQ; red-fleshed) loquat (Eriobotrya japonica), a detailed microscopic analysis of plastid development during fruit ripening was carried out. In peel cells, chloroplasts turned into smaller chromoplasts in both cultivars, and the quantity of plastids in LYQ increased by one-half during fruit ripening. The average number of chromoplasts per peel cell in fully ripe fruit was similar between the two cultivars, but LYQ peel cell plastids were 20% larger and had a higher colour density, associated with the presence of larger plastoglobules. In flesh cells, chromoplasts could be observed only in LYQ during the middle and late stages of ripening, and the quantity on a per-cell basis was higher than that in peel cells, but the size of chromoplasts was smaller. It was concluded that chromoplasts are derived from the direct conversion of chloroplasts to chromoplasts in the peel, and from de novo differentiation of proplastids into chromoplasts in flesh. The relationship between plastid development and carotenoid accumulation is discussed
Analysis of Volatile Components of Auricularia auricula from Different Origins by GC-MS Combined with Electronic Nose
Auricularia auricula is a kind of nutrient-rich edible fungus, which has the reputation of “king of vegetarians.” In this paper, the electronic nose combined with GC-MS technology was used to analyze the volatile components of A. auricula in Heilongjiang, Jilin, Shanghai, and Sichuan provinces to investigate the differences and characteristics of A. auricula in different origins. The results showed that the electronic nose could obviously distinguish the samples from Jilin and Shanghai with a high degree of discrimination, while it was inappropriate to distinguish the samples from Heilongjiang and Sichuan Province. GC-MS was used to further analyze the volatile compounds in A. auricula qualitatively and quantitatively. The results showed that 98 volatile components were detected and 23 of them were common components, including alcohols, aldehydes, acids, esters, hydrocarbons, and other volatile components. The relative content of acetic acid and diethyl azodicarboxylate in A. auricula from the four origins was relatively high. According to the relative odor activity value (ROAV), it was found that the key compounds that caused the aroma difference between different origins were 1-octene-3-ol, cis-3-nonene-1-ol, (E)-2-octenal, (E)-2-nonenal, (E,E)-2,4-nonadienal, and 3-methyl butanal