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31.
Fortuna?Ponte Gloria?MazzoneEmail authorView authors OrcID profile Nino?Russo Emilia?Sicilia 《Journal of molecular modeling》2018,24(7):183
Density functional theory and its time-dependent extension (DFT, TDDFT) were employed to establish the feasibility of using a series of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPYs) in photodynamic therapy. Their absorption electronic spectra, singlet–triplet energy gaps, and spin–orbit matrix elements were computed and are discussed here. The effects of bromine substitution on the photophysical properties of BODIPY were elucidated. The investigated compounds were found to possess different excited triplet states that lie below the energy of the bright excited singlet state (S1 or S2), depending on the positions occupied by the bromine atoms. The computed spin–orbit matrix elements for the radiationless intersystem crossing Sn?→ ?Tm and the relative singlet–triplet energy gaps allowed the prediction of plausible nonradiative decay pathways for the production of singlet excited molecular oxygen, the key cytotoxic agent in photodynamic therapy. 相似文献
32.
A. Russo F. Angelini R. Carotenuto F. M. Guarino C. Falugi C. Campanella 《Polar Biology》2000,23(4):279-287
Testis structure and spermatogenetic activity were studied in two Antarctic teleostean species, Chionodraco hamatus and Trematomus bernacchii, captured during the austral summer in the Ross Sea. The specimens of C. hamatus showed full reproductive activity but, the spermatogenetic cycle being over, only spermatogonia and Sertoli cells were present
in the seminiferous tubules whereas the lumina were full of sperm. By contrast, the specimens of T. bernacchii were in the stage of spermatogenetical recrudescence, having not yet entered the reproductive period. In this species, the
seminiferous tubules were devoid of lumen and full of spermatogonial cysts, showing some mitoses. Many tubules contained cysts
of meiotic spermatocytes I and, in one case only, small cysts of spermatocytes II. The final stages of spermatogenesis were
lacking, presumably occurring later, in autumn/winter. The immunocytochemical tests aimed at identifying bFGF and FGFR1 revealed
a positive reaction both in Sertoli cells and spermatogonia in the C. hamatus specimens, indicating that this species was ready to start a new spermatogenetic cycle. The weak reaction in the specimens
of T. bernacchii suggests that, in this species, the stage of cell division was over and that of meiosis and differentiation was starting.
These data indicate that Antarctic fish have an opportunistic spermatogenetic cycle.
Accepted: 24 October 1999 相似文献
33.
Coccetti P Zinzalla V Tedeschi G Russo GL Fantinato S Marin O Pinna LA Vanoni M Alberghina L 《Biochemical and biophysical research communications》2006,346(3):786-793
We have previously identified Ser201 of Sic1, a yeast cyclin-dependent kinase inhibitor, as an in vitro target of protein kinase CK2. Here we present new evidence, by using specific anti-P-Ser201 antibodies and 2-D gel electrophoresis coupled to MALDI mass spectrometry analysis, that Sic1 is phosphorylated in vivo on Ser201 shortly after its de novo synthesis, during late anaphase in glucose-grown cells. This phosphorylation is also detected in Sic1 immunopurified from G1 cells. In agreement with these data we also show that the catalytic alpha' subunit of CK2, whose function is required for cell cycle progression, is detected in Sic1 immunopurified complexes, and that phosphorylation on Ser201 is reduced after CK2 inactivation at the non-permissive temperature in a cka1delta cka2(ts) yeast strain. These data strongly support the notion that CK2 phosphorylates Sic1 in vivo. 相似文献
34.
We describe a chemo-enzymatic synthesis of 3'- and 6'-O-sialyllactose, two trisaccharides occurring in the 'acidic fraction' of the human milk oligosaccharides and endowed with potential antiadhesive activity. The key step is the highly regioselective 6'-O-acylation of benzyllactoside, which gave access to suitably protected lactose building blocks to be used as acceptors in the sialylation reaction. Moreover, the synthesis of the carboxymethyl and sulfo analogues of the title compounds is reported. 相似文献
35.
36.
Insulin-stimulated ribosomal protein synthesis in maize embryonic axes during germination 总被引:1,自引:0,他引:1
Estela Sánchez de Jiménez Elda Beltrán-Peña Adriana Ortíz-López 《Physiologia plantarum》1999,105(1):148-154
Addition of insulin to maize seed ( Zea mays L. cv. Chalqueño) was found to accelerate germination and seedling growth. Insulin-stimulated maize axes showed enhancement of 35 S-methionine incorporation into ribosomal proteins (rp) and mobilization of S6 rp mRNA into polysomes. Increase in S6 rp phosphorylation of the small ribosomal subunit (40S) was observed in 32 P-orthophosphate pulse-labeled experiments when maize axes were stimulated by insulin. Application of either wortmannin or rapamycin, inhibitors of protein kinases of the insulin transduction pathway, abolished the insulin stimulatory effect on S6 rp phosphorylation and on ribosomal protein synthesis. The above data are interpreted as an indication of the existence of an insulin-stimulated signal transduction pathway in maize tissues that is involved in the regulation of translation. 相似文献
37.
Ciravolo V Huber V Ghedini GC Venturelli E Bianchi F Campiglio M Morelli D Villa A Della Mina P Menard S Filipazzi P Rivoltini L Tagliabue E Pupa SM 《Journal of cellular physiology》2012,227(2):658-667
Exosomes are endosome-derived nanovesicles actively released into the extracellular environment and biological fluids, both under physiological and pathological conditions, by different cell types. We characterized exosomes constitutively secreted by HER2-overexpressing breast carcinoma cell lines and analyzed in vitro and in vivo their potential role in interfering with the therapeutic activity of the humanized antibody Trastuzumab and the dual tyrosine kinase inhibitor (TKI) Lapatinib anti-HER2 biodrugs. We show that exosomes released by the HER2-overexpressing tumor cell lines SKBR3 and BT474 express a full-length HER2 molecule that is also activated, although to a lesser extent than in the originating cells. Release of these exosomes was significantly modulated by the growth factors EGF and heregulin, two of the known HER2 receptor-activating ligands and naturally present in the surrounding tumor microenvironment. Exosomes secreted either in HER2-positive tumor cell-conditioned supernatants or in breast cancer patients' serum bound to Trastuzumab. Functional assays revealed that both xenogeneic and autologous HER2-positive nanovesicles, but not HER2-negative ones, inhibited Trastuzumab activity on SKBR3 cell proliferation. By contrast, Lapatinib activity on SKBR3 cell proliferation was unaffected by the presence of autologous exosomes. Together, these findings point to the role of HER2-positive exosomes in modulating sensitivity to Trastuzumab, and, consequently, to HER2-driven tumor aggressiveness. 相似文献
38.
L-Propionyl-carnitine as superoxide scavenger, antioxidant, and DNA cleavage protector 总被引:5,自引:0,他引:5
Vanella A Russo A Acquaviva R Campisi A Di Giacomo C Sorrenti V Barcellona ML 《Cell biology and toxicology》2000,16(2):99-104
L-Propionylcarnitine, a propionyl ester of L-carnitine, increases the intracellular pool of L-carnitine. It exhibits a high
affinity for the enzyme carnitine acetyltransferase (CAT) and, thus, is readily converted into propionyl-coenzyme A and free
carnitine.
It has been reported that L-propionylcarnitine possesses a protective action against heart ischemia–reperfusion injury; however,
the antioxidant mechanism is not yet clear. L-Propionylcarnitine might reduce the hydroxyl radical production in the Fenton
system, by chelating the iron required for the generation of hydroxyl radicals. To obtain a better insight into the antiradical
mechanism of L-propionylcarnitine, the present research analyzed the superoxide scavenging capacity of L-propionylcarnitine
and its effect on linoleic acid peroxidation. In addition, the effect of L-propionylcarnitine against DNA cleavage was estimated
using pBR322 plasmid. We found that L-propionylcarnitine showed a dose-dependent free-radical scavenging activity. In fact,
it was able to scavenge superoxide anion, to inhibit the lipoperoxidation of linoleic acid, and to protect pBR322 DNA from
cleavage induced by H2O2 UV-photolysis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
39.
Annunziata Mauro Alessandra Martelli Paolo Berardinelli Valentina Russo Nicola Bernabò Oriana Di Giacinto Mauro Mattioli Barbara Barboni 《PloS one》2014,9(4)
Background
The success of ovarian follicle growth and ovulation is strictly related to the development of an adequate blood vessel network required to sustain the proliferative and endocrine functions of the follicular cells. Even if the Vascular Endothelial Growth Factor (VEGF) drives angiogenesis before ovulation, the local role exerted by Progesterone (P4) remains to be clarified, in particular when its concentration rapidly increases before ovulation.Aim
This in vivo study was designed to clarify the effect promoted by a P4 receptor antagonist, RU486, on VEGF expression and follicular angiogenesis before ovulation, in particular, during the transition from pre to periovulatory follicles induced by human Chorionic Gonadotropins (hCG) administration.Material and Methods
Preovulatory follicle growth and ovulation were pharmacologically induced in prepubertal gilts by combining equine Chorionic Gonadotropins (eCG) and hCG used in the presence or absence of RU486. The effects on VEGF expression were analyzed using biochemical and immunohistochemical studies, either on granulosa or on theca layers of follicles isolated few hours before ovulation. This angiogenic factor was also correlated to follicular morphology and to blood vessels architecture.Results and Conclusions
VEGF production, blood vessel network and follicle remodeling were impaired by RU486 treatment, even if the cause-effect correlation remains to be clarified. The P4 antagonist strongly down-regulated theca VEGF expression, thus, preventing most of the angiogenic follicle response induced by hCG. RU486-treated follicles displayed a reduced vascular area, a lower rate of endothelial cell proliferation and a reduced recruitment of perivascular mural cells. These data provide important insights on the biological role of RU486 and, indirectly, on steroid hormones during periovulatory follicular phase. In addition, an in vivo model is proposed to evaluate how periovulatory follicular angiogenesis may affect the functionality of the corpus luteum (CL) and the success of pregnancy. 相似文献40.
Circulating miR‐22, miR‐24 and miR‐34a as Novel Predictive Biomarkers to Pemetrexed‐Based Chemotherapy in Advanced Non‐Small Cell Lung Cancer 下载免费PDF全文