A series of platinum(II) amidine complexes were previously prepared with the aim of obtaining a new class of platinum-based antitumour drugs. This series includes compounds of the type ...cis--PtCl2{Z-HN=C(NHMe)Me}2 and trans-PtCl2{Z-HN=C(NHMe)Me}2 (1, 2), cis-PtCl2{E-HN=C(NMe2)Me}2 and trans-PtCl2{E-HN=C(NMe2)Me}2 (3, 4), cis-PtCl2{Z-HN=C(NHMe)Ph}2 and trans-PtCl2{Z-HN=C(NHMe)Ph}2 (5, 6), and cis-PtCl2{HN=C(NMe2)Ph}2 and trans-PtCl2{HN=C(NMe2)Ph}2 (7, 8). The reactions with dimethyl sulfoxide were studied for complexes 5-8; the formation of cationic species containing coordinated dimethyl sulfoxide was demonstrated by NMR experiments and electrospray ionization mass spectrometry. In this work, the amidine platinum(II) complexes were tested for their in vitro cytotoxicity on a panel of various human cancer cell lines. The results indicate that the benzamidine complex 8 was the most effective derivative also circumventing acquired cisplatin resistance as demonstrated by chemosensitivity tests performed on cisplatin-sensitive and cisplatin-resistant cell lines. The studies concerning the cellular DNA damage on both parental chemosensitive and resistant sublines suggest for the new trans-amidine complex a different mechanism of action compared with that exhibited by cisplatin.
A novel hyperspectral confocal microscopy method to separate different cell populations in a co‐culture model is presented here. The described methodological and instrumental approach allows ...discrimination of different cell types using a non‐invasive, label free method with good accuracy with a single cell resolution. In particular, melanoma cells are discriminated from HaCaT cells by hyperspectral confocal imaging, principal component analysis and optical frequencies signing, as confirmed by fluorescence labelling cross check. The identification seems to be quite robust to be insensitive to the cellular shape within the studied samples, enabling to separate cells according to their cytotype down to a single cell sensitivity.
Set of hyperspectral images of melanoma‐keratinocytes co‐culture model (left), score plot of principal component analysis and spectral analysis of principal components coefficients (center), label‐free spectral identification of cell populations (right).
A novel hyperspectral confocal microscopy method to separate different cell populations in a co‐culture model is presented. The described methodological and instrumental approach allows discrimination of different cell types using a non‐invasive, label free method with good accuracy with a single cell resolution. In particular, melanoma cells are discriminated from HaCaT cells by hyperspectral confocal imaging, principal component analysis and optical frequencies signing, as confirmed by fluorescence labelling cross check.
We report the design and implementation of a new reflectance laser scanning confocal system with spectroscopy imaging capabilities. Confocal spectroscopy is achieved by using a very broad spectral ...range supercontinuum source capable of high precision reflectance data in the VIS-IR spectral range thanks to an almost achromatic optical layout. With this apparatus we collect each single scanning point as a whole spectrum in a continuous range, associated with the optical section imaging possibilities typical of a confocal set up. While such a microscope has been developed for bio medical analysis of human skin and other similar applications, first test results on solid samples produce spectroscopic results that, compared to analytical models based on the Abelés matrix transfer methods, show a very good agreement, opening new possibilities of a complete spectroscopic fingerprinting of samples with microscopic details.
Fluorine containing phosphazene polymers Gleria, Mario; Bertani, Roberta; Jaeger, Roger De ...
Journal of fluorine chemistry,
02/2004, Letnik:
125, Številka:
2
Journal Article
Recenzirano
The synthesis, characterization, and practical exploitation of fluorinated phosphazene polymers and copolymers are shortly reviewed. Particular emphasis has been devoted to the contribution of ...Italian research groups to this topic.
In this paper we highlighted the synthesis, characterization, and practical exploitation of different types of polyphosphazenes substituted with fluorinated groups. There are several ways in which fluorine atoms can be inserted into polyphosphazenes, all of which leading to different polymers showing a wide range of characteristics. In general it is true that the insertion of fluorine atoms into phosphazene macromolecules leads to an enhancement of the thermal stability, flame resistance, low-temperature elastomericity, and chemical inertness of the phosphazenes obtained. The contribution of Italian research groups to the preparation and exploitation of organic commercial macromolecules grafted onto fluorinated polyphosphazenes is also reviewed.
Microbial products, including lipopolysaccharide (LPS), an agonist of Toll-like receptor 4 (TLR4), regulate the lifespan of dendritic cells (DCs) by largely undefined mechanisms. Here, we identify a ...role for calcium-calmodulin–dependent kinase IV (CaMKIV) in this survival program. The pharmacologic inhibition of CaMKs as well as ectopic expression of kinase-inactive CaMKIV decrease the viability of monocyte-derived DCs exposed to bacterial LPS. The defect in TLR4 signaling includes a failure to accumulate the phosphorylated form of the cAMP response element-binding protein (pCREB), Bcl-2, and Bcl-xL. CaMKIV null mice have a decreased number of DCs in lymphoid tissues and fail to accumulate mature DCs in spleen on in vivo exposure to LPS. Although isolated Camk4−/− DCs are able to acquire the phenotype typical of mature cells and release normal amounts of cytokines in response to LPS, they fail to accumulate pCREB, Bcl-2, and Bcl-xL and therefore do not survive. The transgenic expression of Bcl-2 in CaMKIV null mice results in full recovery of DC survival in response to LPS. These results reveal a novel link between TLR4 and a calcium-dependent signaling cascade comprising CaMKIV-CREB-Bcl-2 that is essential for DC survival.
Poly(butylene terephthalate) (PBT) and a sample of polyamide have been melt processed in the presence of two new phosphazene compounds, namely ...2,2-dichloro-4,4,6,6-bisspiro(2′,2″dioxy-1′,1″biphenyl)cyclotriphosphazene (2Cl-CP) and 2,2-bis-(2-methoxy-4-methyleneoxy-phenoxy)-4,4,6,6,-bisspiro(2′,2″dioxy-1′,1″biphenyl)cyclophosphazene (CP-2EPOX).
The blends were prepared by using polyamide 6 (PA6) at 25/75
w/w and 75/25
w/w composition. In order to perform a preliminary analysis on the behaviour of the blends, the materials were prepared in a batch mixer.
The materials have been completely characterized from a rheological, morphological, mechanical point of view. The results indicate that the additives used cause an increase of the rupture properties and of the viscosity especially in the PA-rich blend. This result can be attributed to a chain extension effect on the PA phase, even if some compatibilisation with the formation of PBT/PA6 copolymers cannot be excluded as evidenced by the reduction of particle dimensions and by the improvement of the adhesion between the phases. Between the two compatibilisers, the CP-2EPOX displays the best results for both the investigated compositions while 2Cl-CP seems to act simply as a PA6 chain extender with very low compatibilising effect.
Poly(butylene terephthalate) (PBT) and a sample of polyamide have been melt processed in the presence of two new phosphazene compounds, namely ...2,2-dichloro-4,4,6,6-bisspyro(2′,2″-dioxy-1′,1″-biphenyl)cyclotriphosphazene (2Cl-CP) and 2,2-bis(2-methoxy-4-methyleneoxy-phenoxy)-4,4,6,6-bisspyro(2′,2″-dioxy-1′,1″-biphenyl)cyclophosphazene (CP-2EPOX).
The blends were prepared by using polyamide 6 (PA6) and polyamide 6,6 (PA66) in 25/75 and 75/25
w/w compositions by using a co-rotating twin-screw extruder.
The materials have been completely characterized from a mechanical, rheological, and morphological point of view. The results indicate that the additives used cause an increase of the rupture properties and of the viscosity, especially in the PA6 rich blends containing CP-2EPOX. This result can be not only attributed to a chain extension effect on the PA phase but also to
in situ formation of PA/PBT copolymers promoted by the presence of the CP compound as confirmed by NMR and MALDI-TOF analyses. The compatibilization effect fades in blends containing PA66, probably due to a thermal deactivation of the additives at higher temperature required to process this polymer.
The objective of this study was to identify differentially expressed genes in the anterior pituitary (AP) of sows selected for enhanced reproductive phenotypes. Selection in the Index (I) line was ...based on an index of ovulation rate and embryo survival, whereas random selection was used in the Control (C) line. Average numbers of fully formed piglets at birth were 12.5 +/- 1.5 and 9.9 +/- 2.0 for Line I and C sows used in this study, respectively. In order to induce luteolysis and synchronize follicle development, sows were injected (i.m.) with 2 mL of prostaglandin F2alpha analog between d 12 and 14 of the estrous cycle. Tissue was harvested 2 d (d2) or 4 d (d4) after injection, resulting in four experimental groups: Cd2 (n = 6), Cd4 (n = 4), Id2 (n = 6), and Id4 (n = 7). Differential display PCR (ddPCR) was used to search for transcriptional changes between selection lines in the AP, using samples within line but pooled across days. Northern hybridization was used to confirm ddPCR results. For ddPCR, two pools were used from each line (C and I). Three genes were confirmed to be differentially expressed between Lines I and C: G-beta like protein, ferritin heavy-chain, and follicle stimulating hormone beta subunit, whereas many other expressed sequence tags were observed to be differentially expressed but still require confirmation. Our findings indicate that long-term selection to increase ovulation rate and decrease embryo mortality has altered transcriptional patterns in the anterior pituitary, most likely as correlated responses.
Graphic
The synthesis and physico-chemical characterization of 1,1,2,2-tetrakis(perfluoroalkyl-methylene)ethane {F(CF
2)
n
CH
2
2CH}
2 (
n=6,
TK6;
n=8,
TK8) are reported. The synthesis consists of ...four steps: (1) addition of allyl alcohol to a perfluoroalkyl iodide, F(CF
2)
n
I (
n=6,8) to give the corresponding iodo-adduct; (2) dehalogenation of the adduct by treatment with zinc in aqueous acetic acid, yielding 3-perfluoro-
n-alkyl-1-propene; (3) addition of 3-perfluoro-
n-alkyl-l-propene to perfluoroalkyl iodide, F(CF
2)
n
I (
n=6,8) to give 1,3-perfluoro-
n-alkyl-2-iodo-propane; (4) coupling of 1,3-perfluoro-
n-alkyl-2-iodo-propane by zinc in acetic anhydride giving the final products. TK6 and TK8 are characterized by very low surface tension values and exhibit very good properties as potential ski-waxes.
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