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21.
Organization of immune responses requires exchange of information between cells. This is achieved through either direct cell–cell contacts and establishment of temporary synapses or the release of soluble factors, such as cytokines and chemokines. Here we show a novel form of cell‐to‐cell communication based on adenosine triphosphate (ATP). ATP released by stimulated T cells induces P2X4/P2X7‐mediated calcium waves in the neighboring lymphocytes. Our data obtained in lymph node slices suggest that, during T‐cell priming, ATP acts as a paracrine messenger to reduce the motility of lymphocytes and that this may be relevant to allow optimal tissue scanning by T cells.  相似文献   
22.

Background

Although the thrombin binding aptamer (TBA) is endowed with both anticoagulant and antiproliferative properties, it is possible to reduce the first and enhance the second one by suitable chemical modifications.

Methods

Two oligonucleotides (TBA353 and TBA535) based on the TBA sequence (GGTTGGTGTGGTTGG) and containing inversion of polarity sites have been investigated by CD, UV and electrophoretic techniques for their ability to form G-quadruplex structures. Furthermore, their anticoagulant (PT assay), antiproliferative (MTT assay) and anti-motility (wound healing assay) properties against Calu-6 cells have been tested and compared with TBA.

Results

CD, UV and electrophoresis data indicate that both ODNs are able to form G-quadruplex structures. Particularly, results suggest that TBA535 adopts a G-quadruplex structure characterized by a loop arrangement different from that of TBA. Both TBA analogues drop the anticoagulant activity. However, TBA535 is endowed with a significant antiproliferative activity against lung cancer Calu-6 cells. Importantly, both TBA and TBA535 possess a remarkable anti-motility property against the same cell line.

Conclusions

Both TBA analogues TBA353 and TBA535 are able to form G-quadruplex structures with no anticoagulant activity. However only TBA535 is endowed with noteworthy antiproliferative and anti-motility properties against lung cancer Calu-6 cells.

General significance

The switching from the anticoagulant to antiproliferative property can be obtained also in TBA derivatives not adopting the “chair-like” G-quadruplex structure typical of TBA. Furthermore, results have highlighted an unprecedented anti-cell-motility property of TBA and TBA535 reinforcing the potential of these ODNs as anticancer drugs.  相似文献   
23.
Uveal melanoma is an aggressive cancer that metastasizes to the liver in about half of the patients, with a high lethality rate. Identification of patients at high risk of metastases may provide indication for a frequent follow-up for early detection of metastases and treatment. The analysis of the gene expression profiles of primary human uveal melanomas showed high expression of SDCBP gene (encoding for syndecan-binding protein-1 or mda-9/syntenin), which appeared higher in patients with recurrence, whereas expression of syndecans was lower and unrelated to progression. Moreover, we found that high expression of SDCBP gene was related to metastatic progression in two additional independent datasets of uveal melanoma patients. More importantly, immunohistochemistry showed that high expression of mda-9/syntenin protein in primary tumors was significantly related to metastatic recurrence in our cohort of patients. Mda-9/syntenin expression was confirmed by RT-PCR, immunofluorescence and immunohistochemistry in cultured uveal melanoma cells or primary tumors. Interestingly, mda-9/syntenin showed both cytoplasmic and nuclear localization in cell lines and in a fraction of patients, suggesting its possible involvement in nuclear functions. A pseudo-metastatic model of uveal melanoma to the liver was developed in NOD/SCID/IL2Rγ null mice and the study of mda-9/syntenin expression in primary and metastatic lesions revealed higher mda-9/syntenin in metastases. The inhibition of SDCBP expression by siRNA impaired the ability of uveal melanoma cells to migrate in a wound-healing assay. Moreover, silencing of SDCBP in mda-9/syntenin-high uveal melanoma cells inhibited the hepatocyte growth factor (HGF)-triggered invasion of matrigel membranes and inhibited the activation of FAK, AKT and Src. Conversely syntenin overexpression in mda-9/syntenin-low uveal melanoma cells mediated opposite effects. These results suggest that mda-9/syntenin is involved in uveal melanoma progression and that it warrants further investigation as a candidate molecular marker of metastases and a potential therapeutic target.  相似文献   
24.
25.
Sericin was extracted from three strains of Thai Bombyx mori silk cocoons (white shell Chul1/1, greenish shell Chul3/2, and yellow shell Chul4/2) by a high-pressure and high-temperature technique. The characteristics of sericin extracted from different fractions (15, 45, and 60 min extraction process) were compared. No differences in amino acid composition were observed among the three fractions. For all silk strains, sericin extracted from a 15-min process presented the highest molecular weight. The biological potential of the different sericin samples as a bioadditive for 3T3 fibroblast cells was assessed. When comparing sericin extracted from three silk strains, sericin fractions extracted from Chul4/2 improved cell proliferation, while sericin from Chul 1/1 activated Type I collagen production to the highest extent. This study allows the natural variability of sericin obtained from different sources and extraction conditions to be addressed and provides clues for the selection of sericin sources.  相似文献   
26.
A protein kinase, type NII, has been purified from wheat germ chromatin. The enzyme, which uses both ATP and GTP as phosphoryl donors, catalyzes the phosphorylation of casein, phosvitin and E. coli RNA polymerase, but not of histone proteins. Polypeptide bands at 46 kDa, 37 kDa and 25 kDa were estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autophosphorylation of the 25 kDa subunit was observed following incubation of the purified kinase with (-32P)ATP and (-32P)GTP.  相似文献   
27.
The subcellular localization of calcium in cells of symbiotic partners located within leaf cavities of Azolla was investigated by using chlorotetracycline, ESI and EELS analysis. Loosely membrane-bound calcium was evidenced by using CTC or EGTA and CTC, in cytoplasmic regions of Azolla hair cells and in cytoplasm of the cyanobiont. Tightly membrane-bound calcium revealed by CTC, and ESI and EELS analysis, was observed in cyanophycin granules and carboxysomes of the cyanobiont. A third calcium type, revealed by ESI and EELS analysis, was localized at the level of cell walls of simple and branched Azolla hairs, in the envelope of heterocysts, and in the cell walls of the cyanobiont.  相似文献   
28.

Background

Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.

Objective

To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.

Population and Methods

The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.

Results

The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.

Conclusions

The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.  相似文献   
29.
30.
From the aerial parts of Scutellaria hastifolia, family Lamiaceae (Labiatae), seven neo-clerodane diterpenoids (hastifolins A–G) were isolated. The products are similar to the known scuteparvin and are characterized by being trans-cinnamoyl derivatives. Structures and stereochemistry were determined by intensive NMR investigation. Six of the products form three pairs of epimers at C-13. Hastifolins A–C showed significant antifeedant activity.  相似文献   
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