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81.
Carlos Arrabal María Concepción García-Vallejo Estrella Cadahia Manuel Cortijo Brigida Fernández de Simón 《Plant Systematics and Evolution》2012,298(2):511-522
The existence of two chemotypes of Pinus pinaster, on the basis of the chemical composition of the resin acids in their needles, is known. An investigation was performed on
54 samples of needles of Spanish Pinus pinaster to study the differences between these chemotypes on the basis of monoterpene, sesquiterpene, neutral diterpene, fatty acid,
and resin acid composition. One-hundred and twelve compounds were identified by GC–FID and GC–MS. Statistical analysis of
the results established the existence of two groups or chemotypes, in the ratio of 5:1. In one chemotype, total acid compounds
were more abundant than neutral compounds, whereas in the other the concentrations of both neutral and acid compounds were
similar. Distinction of the chemotypes was based on the presence/absence of a sesquiterpene (germacrene d-4-ol acetate), neutral diterpenes (8(14),13(15)-abietadiene, anticopalol, an isomer of anticopalol, and pimarol), fatty acids
(10-octadecenoic, 14-hydroxy-10-octadecenoic, and 13-hydroxy-9-octadenoic acids and an unidentified fatty acid), and resin
acids (levopimaric + palustric, eperuic, and anticopalic acids, and three isomers of anticopalic acid); and on the different
relative percentages of other compounds of these types. This study gives a wide view of the composition of the needles of
Pinus pinaster, improving the differentiation of chemotypes on the basis of terpene and acid composition. 相似文献
82.
Gualano B Everaert I Stegen S Artioli GG Taes Y Roschel H Achten E Otaduy MC Junior AH Harris R Derave W 《Amino acids》2012,43(1):21-24
Carnosine is present in high concentrations in skeletal muscle where it contributes to acid buffering and functions also as a natural protector against oxidative and carbonyl stress. Animal studies have shown an anti-diabetic effect of carnosine supplementation. High carnosinase activity, the carnosine degrading enzyme in serum, is a risk factor for diabetic complications in humans. The aim of the present study was to compare the muscle carnosine concentration in diabetic subjects to the level in non-diabetics. Type 1 and 2 diabetic patients and matched healthy controls (total n=58) were included in the study. Muscle carnosine content was evaluated by proton magnetic resonance spectroscopy (3 Tesla) in soleus and gastrocnemius. Significantly lower carnosine content (-45%) in gastrocnemius muscle, but not in soleus, was shown in type 2 diabetic patients compared with controls. No differences were observed in type 1 diabetic patients. Type II diabetic patients display a reduced muscular carnosine content. A reduction in muscle carnosine concentration may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle. 相似文献
83.
Medrano LM García-Magariños M Dema B Espino L Maluenda C Polanco I Figueredo MÁ Fernández-Arquero M Núñez C 《PloS one》2012,7(2):e31244
Th17 cells are known to be involved in several autoimmune or inflammatory diseases. In celiac disease (CD), recent studies suggest an implication of those cells in disease pathogenesis. We aimed at studying the role of genes relevant for the Th17 immune response in CD susceptibility. A total of 101 single nucleotide polymorphisms (SNPs), mainly selected to cover most of the variability present in 16 Th17-related genes (IL23R, RORC, IL6R, IL17A, IL17F, CCR6, IL6, JAK2, TNFSF15, IL23A, IL22, STAT3, TBX21, SOCS3, IL12RB1 and IL17RA), were genotyped in 735 CD patients and 549 ethnically matched healthy controls. Case-control comparisons for each SNP and for the haplotypes resulting from the SNPs studied in each gene were performed using chi-square tests. Gene-gene interactions were also evaluated following different methodological approaches. No significant results emerged after performing the appropriate statistical corrections. Our results seem to discard a relevant role of Th17 cells on CD risk. 相似文献
84.
Identification of olive (Olea europaea) seed and pulp proteins by nLC-MS/MS via combinatorial peptide ligand libraries 总被引:1,自引:0,他引:1
Esteve C D'Amato A Marina ML García MC Citterio A Righetti PG 《Journal of Proteomics》2012,75(8):2396-2403
Different types of extraction protocols are described for identifying proteins in seed and pulp of olive (Olea europea), by employing both conventional extraction methods and capture with ProteoMiner as well as with in house-made combinatorial peptide ligand libraries (HM-CPLLs) at pH 7.4 and at pH 2.2. Thanks to the use of CPLLs, able to dramatically amplify the signal of low-abundance species, a quite large number of compounds has been indeed identified: 61 in the seed (vs. only four reported in current literature) and 231 in the pulp (vs. 56 described so far), the deepest investigation up to the present of the olive proteome. In the seed, it highlights the presence of seed storage proteins, oleosins and histones. In the pulp, the allergenic thaumatin-like protein (Ole e 13) was confirmed, among the other 231, as the most abundant protein in the olive pulp. The present research has also been undertaken with the aim of identifying proteins in olive oil and ascertaining the relative contribution of seed and pulp proteins in their presence, if any, in oils. 相似文献
85.
86.
Saúl Herranz-Martín David Jimeno Antonio E. Paniagua Almudena Velasco Juan M. Lara José Aijón Concepción Lillo 《PloS one》2012,7(11)
CRB3 (Crumbs homologue 3), a member of the CRB protein family (homologous to the Drosophila Crumbs), is expressed in different epithelium-derived cell types in mammals, where it seems to be involved in regulating the establishment and stability of tight junctions and in ciliogenesis. This protein has been also detected in the retina, but little is known about its localization and function in this tissue. Our goal here was to perform an in-depth study of the presence of CRB3 protein in the mouse retina and to analyze its expression during photoreceptor ciliogenesis and the establishment of the plexiform retinal layers. Double immunofluorescence experiments for CRB3 and well-known markers for the different retinal cell types were performed to study the localization of the CRB3 protein. According to our results, CRB3 is present from postnatal day 0 (P0) until adulthood in the mouse retina. It is localized in the inner segments (IS) of photoreceptor cells, especially concentrated in the area where the connecting cilium is located, in their synaptic terminals in the outer plexiform layer (OPL), and in sub-populations of amacrine and bipolar cells in the inner plexiform layer (IPL). 相似文献
87.
de la Concepción Matesanz M Feito MJ Ramírez-Santillán C Lozano RM Sánchez-Salcedo S Arcos D Vallet-Regí M Portolés MT 《Macromolecular bioscience》2012,12(4):446-453
Therapeutic strategies for bone regeneration involve the selection of suitable biomaterials, growth factors, and cell types to mimic the cellular microenvironment where molecular and mechanical signals control the reconstruction of bone tissue. The immobilization of basic fibroblast growth factor (FGF-2) on powdered silicon-substituted hydroxyapatite (Si-HA) allows to prepare a biofunctional biomaterial able to interact with bone cells in a very specific way. The biological activity of FGF-2/Si-HA, evaluated in Saos-2 osteoblasts and MC3T3-E1 preosteoblasts through the PLCγ and MAPK/ERK signal transduction pathways, shows that FGF-2 immobilized on Si-HA provides the right signals to cells stimulating crucial intracellular mechanisms of osteoblast proliferation and differentiation. 相似文献
88.
Apical meristems play a central role in plant development. Self-renewing cells in the central region of the shoot meristem replenish the cell population in the peripheral region, where organ primordia emerge in a predictable pattern, and in the underlying rib meristem, where new stem tissue is formed. While much is known about how organ primordia are initiated and their lateral boundaries established, development at the interface between the stem and the meristem or the lateral organs is poorly understood. Here, we show that the BELL-type ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1) is required for proper development of the boundary between the stem and both vegetative and reproductive organs and that this role partially overlaps with that of CUP-SHAPED COTYLEDON genes. During the vegetative phase, ATH1 also functions redundantly with light-activated genes to inhibit growth of the region below the shoot meristem. Consistent with a role in inhibiting stem growth, ATH1 is downregulated at the start of inflorescence development and ectopic ATH1 expression prevents growth of the inflorescence stem by reducing cell proliferation. Thus, ATH1 modulates growth at the interface between the stem, meristem, and organ primordia and contributes to the compressed vegetative habit of Arabidopsis thaliana. 相似文献
89.
Barcala M García A Cubas P Almoguera C Jordano J Fenoll C Escobar C 《Plant molecular biology》2008,66(1-2):151-164
90.
Immunolocalization of beclin 1, a bcl-2-binding,autophagy-related protein,in the human ovary: possible relation to life span of corpus luteum 总被引:1,自引:0,他引:1
Ovarian tissue homeostasis is maintained by highly regulated cyclic phases of cell proliferation/differentiation and programmed
cell death. Compelling evidence indicates that both apoptotic and autophagic types of programmed cell death are involved in
the regression of the corpus luteum (CL) in primate species. Beclin 1 is an autophagy-related protein that is involved in
the inter-relationships between apoptosis and autophagy, through interaction with the anti-apoptotic protein bcl-2. We studied
the presence and expression pattern of beclin 1 in the adult human ovary. In ovarian follicles, beclin 1 immunostaining was
found in the theca layer, whereas granulosa cells were negative. After ovulation, beclin 1 immunostaining was present in both
theca-lutein and granulosa-lutein areas. The expression of beclin 1 in granulosa-lutein cells was related to the functional
and structural status of the CL, being strong at the early and mid luteal phases, barely detectable at the late luteal phase,
and absent in granulosa-lutein cells in subsequent cycles. Our results indicated that beclin 1 expression was related to luteal
cell survival rather than to cell death. Accordingly, persistent beclin 1 expression was found in granulosa-lutein cells under
either physiological (i.e., CL of pregnancy) or pathological (irregularly regressing CL in climacteric women) conditions involving
prolonged CL life span. Strong beclin 1 immunostaining was also found in ovarian androgen-producing cells (i.e., secondary
interstitial and hilus cells). Our data thus suggest that beclin 1 plays important roles in the regulation of the life span
of human CL and ovarian androgen-secreting cells, by maintaining autophagy at levels promoting cell survival rather than cell
death.
This study was subsidized by grant BFU 2005-01443 from the DGICYT (Spain). 相似文献