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131.
Arobba D Boscato P Boschian G Falgueres C Fasani L Peretto C Sala B Hohenstein UT Tozzi C 《Collegium antropologicum》2004,28(1):5-21
New analysis has been carried out concerning the palaeoenvironmental reconstruction of some Italian sites dating from the Middle Pleistocene to the Bronze Age. Different aspects have been investigated on each site considering the data collected. The following sites have been analyzed: Isernia La Pineta (Molise); Visogliano and Caverna degli Orsi (Tieste); Toirano Caves (Liguria); Grotta Paglicci (Gargano); Riparo del Molare (Salerno); Grotta del Cavallo (Lecce); Castellaro Lagusello (Monzambano, Mantova). 相似文献
132.
Torella D Leosco D Indolfi C Curcio A Coppola C Ellison GM Russo VG Torella M Li Volti G Rengo F Chiariello M 《American journal of physiology. Heart and circulatory physiology》2004,287(6):H2850-H2860
Many older patients, because of their high prevalence of coronary artery disease, are candidates for percutaneous coronary interventions (PCI), but the effects of vascular aging on restenosis after PCI are not yet well understood. Balloon injury to the right carotid artery was performed in adult and old rats. Vascular smooth muscle cell (VSMC) proliferation, apoptotic cell death, together with Akt induction, telomerase activity, p27kip1, and endothelial nitric oxide synthase (eNOS) expression was assessed in isolated arteries. Neointima hyperplasia and vascular remodeling along with endothelial cell regeneration were also measured after balloon injury. Arteries isolated from old rats exhibited a significant reduction of VSMC proliferation and an increase in apoptotic death after balloon injury when compared with adult rats. In the vascular wall of adult rats, balloon dilation induced Akt phosphorylation, and this was barely present in old rats. In arteries from old rats, Akt-modulated cell cycle check points like telomerase activity and p27kip1 expression were decreased and increased, respectively, compared with adults. After balloon injury, old rats showed a significant reduction of neointima formation and an increased vascular negative remodeling compared with adults. These results were coupled by a marked delay in endothelial regeneration in aged rats, partially mediated by a decreased eNOS expression and phosphorylation. Interestingly, chronic administration of L-arginine prevented negative remodeling and improved reendothelialization after balloon injury in aged animals. A decreased neointimal proliferation, an impaired endothelial regeneration, and an increase in vascular remodeling after balloon injury were observed in aged animals. The molecular mechanisms underlying these responses seem to be a reduced Akt and eNOS activity. 相似文献
133.
The presence of alpha-catenin in the VE-cadherin complex is required for efficient transendothelial migration of leukocytes 下载免费PDF全文
Jaap D. van Buul Floris P. van Alphen Peter L. Hordijk 《International journal of biological sciences》2009,5(7):695-705
The majority of the leukocytes cross the endothelial lining of the vessels through cell-cell junctions. The junctional protein Vascular Endothelial (VE)-cadherin is transiently re-distributed from sites of cell-cell contacts during passage of leukocytes. VE-cadherin is part of a protein complex comprising p120-catenin and beta-catenin as intracellular partners. Beta-catenin connects VE-cadherin to alpha-catenin. This VE-cadherin-catenin complex is believed to dynamically control endothelial cell-cell junctions and to regulate the passage of leukocytes, although not much is known about the role of alpha- and beta-catenin during the process of transendothelial migration (TEM). In order to study the importance of the interaction between alpha- and beta-catenin in TEM, we used a cell-permeable version of the peptide encoding the binding site of alpha-catenin for beta-catenin (S27D). The data show that S27D interferes with the interaction between alpha- and beta-catenin and induces a reversible decrease in electrical resistance of the endothelial monolayer. In addition, S27D co-localized with beta-catenin at cell-cell junctions. Surprisingly, transmigration of neutrophils across endothelial monolayers was blocked in the presence of S27D. In conclusion, our results show for the first time that the association of alpha-catenin with the cadherin-catenin complex is required for efficient leukocyte TEM. 相似文献
134.
Stereospecific synthesis of "para-hydroxymexiletine" and sodium channel blocking activity evaluation
Catalano A Carocci A Fracchiolla G Franchini C Lentini G Tortorella V De Luca A De Bellis M Desaphy JF Conte Camerino D 《Chirality》2004,16(2):72-78
Both enantiomers of "para-hydroxymexiletine" (PHM), one of the main metabolites of mexiletine, were synthesized and fully characterized. Properties of (R)- and (S)-PHM, in terms of blocking potency and stereoselectivity on frog skeletal muscle Na(+) channels, were evaluated. The presence of a hydroxy group on the aryloxy moiety in the 4-position, as in PHM, reduced potency with respect to mexiletine in reducing I(Na max). However, PHM showed clear use-dependent behavior similar to that of mexiletine and, in contrast with what is observed with the parent compound, maintained its stereoselectivity during the use-dependent block. Chirality 16:72-78, 2004. 相似文献
135.
Aliaksei?Kisialiou Giordana?Pelone Albino?Carrizzo Giovanni?Grillea Valentina?Trimarco Marina?Marino Michelangelo?Bartolo Alessandro?Marco?De Nunzio Rodolfo?Grella Alessandro?Landolfi Annibale?Puca Claudio?Colonnese Carmine?VecchioneEmail author 《Immunity & ageing : I & A》2012,9(1):22
Background
Thrombolytic therapy (TT) for acute ischemic stroke (AIS) can provoke bleeding’s complication depending on the ischemic lesion (IL) dimension. Inflammation involved in the setting of acute ischaemic stroke, is associated with infarct size. We aimed to study the independent correlation and association between clinical panel of routinely identified biomarkers, including inflammatory parameters, and cerebral IL dimension and site.Results
We evaluated eleven biomarkers in 105 unrelated patients during their hospitalization after acute stroke event. Our data indicate a significant association of: a) confluent IL size with 4th quartile of Erythrocyte Sedimentation Rate (ESR) (OR = 5.250; 95% CI, 1.002 to 27.514) and an independent correlation with sex; b) confluent IL size with 3rd quartile of fibrinogen (OR = 5.5; 95% CI, 1.027 to 29.451); c) confluent IL size with 3rd quartile of platelets (OR= 0.059; 95% CI, 0.003 to 1.175) and independent correlation with sex; d) smaller IL size (OR = 5.25; 95% CI, 1.351 to 20.396) with 3rd quartile of albumin levels and nodular and parenchimal IL size with 2nd (OR = 0.227; 95% CI, 0.053 to 0.981), 3rd (OR = 0.164; 95% CI, 0.038 to 0.711) and 4th (OR = 0.205; 95% CI, 0.048 to 0.870) quartiles albumin levels; e) smaller IL size with 3rd quartile triglycerides (TG) levels (OR = 9; 95% CI, 2.487 to 32.567) and an independent correlation with anterior location. Smaller IL size, anterior AIS turned out to be independently correlated with high serum albumin levels. Finally, high INR and PTT values were associated with worse NIHSS clinical outcomes in contrast to that observed with higher albumin level.Conclusions
We provide evidence of routine biomarkers levels correlation with acute IL size, independently of age and sex. In addition, we highlight the importance of differentiation of biomarkers normal interval levels for further improvement not only of the clinical decision making but also in post-acute clinical outcome management.136.
137.
IL-21 counteracts the regulatory T cell-mediated suppression of human CD4+ T lymphocytes 总被引:12,自引:0,他引:12
Peluso I Fantini MC Fina D Caruso R Boirivant M MacDonald TT Pallone F Monteleone G 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(2):732-739
High expression of IL-21 and/or IL-21R has been described in T cell-mediated inflammatory diseases characterized by defects of counterregulatory mechanisms. CD4(+)CD25(+) regulatory T cells (Treg) are a T cell subset involved in the control of the immune responses. A diminished ability of these cells to inhibit T cell activation has been documented in immune-inflammatory diseases, raising the possibility that inflammatory stimuli can block the regulatory properties of Treg. We therefore examined whether IL-21 controls CD4(+)CD25(+) T cell function. We demonstrate in this study that IL-21 markedly enhances the proliferation of human CD4(+)CD25(-) T cells and counteracts the suppressive activities of CD4(+)CD25(+) T cells on CD4(+)CD25(-) T cells without affecting the percentage of Foxp3(+) cells or survival of Treg. Additionally, CD4(+)CD25(+) T cells induced in the presence of IL-21 maintain the ability to suppress alloresponses. Notably, IL-21 enhances the growth of CD8(+)CD25(-) T cells but does not revert the CD4(+)CD25(+) T cell-mediated suppression of this cell type, indicating that IL-21 makes CD4(+) T cells resistant to suppression rather than inhibiting CD4(+)CD25(+) T cell activity. Finally, we show that IL-2, IL-7, and IL-15, but not IL-21, reverse the anergic phenotype of CD4(+)CD25(+) T cells. Data indicate that IL-21 renders human CD4(+)CD25(-) T cells resistant to Treg-mediated suppression and suggest a novel mechanism by which IL-21 could augment T cell-activated responses in human immune-inflammatory diseases. 相似文献
138.
Fine mapping of the Autosomal Dominant Split Hand/Split Foot Locus on Chromosome 7, Band q21.3-q22.1 总被引:3,自引:3,他引:3 下载免费PDF全文
Stephen W. Scherer Parvoneh Poorkaj Todd Allen Julia Kim Dorrit Geshuri Mark Nunes Sylvia Soder Karen Stephens Roberta A. Pagon Michael A. Patton Mary Anne Berg Tim Donlon Horacio Rivera R. A. Pfeiffer Kenji Naritomi Helen Hughes Maurizio Genuardi Fiorella Gurrieri Giovanni Neri Everett Lovrein Ellen Magenis Lap-Chee Tsui James P. Evans 《American journal of human genetics》1994,55(1):12-20
Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7. 相似文献
139.
Stimulation of carotenoid metabolism in arbuscular mycorrhizal roots 总被引:12,自引:0,他引:12
Fester T Schmidt D Lohse S Walter MH Giuliano G Bramley PM Fraser PD Hause B Strack D 《Planta》2002,216(1):148-154
140.
Area‐wide monitoring of potato tuberworm (Phthorimaea operculella) by pheromone trapping in Northern Italy: phenology,spatial distribution and relationships between catches and tuber damage 下载免费PDF全文
Antonio Masetti Alda Butturini Alberto Lanzoni Valentino De Luigi Giovanni Burgio 《Agricultural and Forest Entomology》2015,17(2):138-145