Fundamental chemistry of iodine. The reaction of di-iodine towards thiourea and its methyl-derivative: formation of aminothiazoles and aminothiadiazoles through dicationic disulfides.

The reactivity of di-iodine towards thiourea (TU) and its derivative methylthiourea (MeTU) was studied. A diversity of products was obtained from these reactions. TU reacted with di-iodine in the absence or presence of hydroiodic or hydrochloric acids in a 1 : 1, 1 : 1 : 1 or 1 : 1 : 2 (TU : I2 : HX (X = I, Cl)) molar ratio to form the ionic compounds [(TU2)(2+)2(I(-))·H2O] (1), [2(TU2) (2+)·(Cl(-))·2(I(-))·(I3(-))] (2) and [(TUH)(+) (I3(-))] (3). The compounds [(TU2)(2+)(Br(-))(I3(-))] (4) and [(TU2)(2+)2(Br(-))·H2O] (5) were derived from the reactions of TU with di-iodine in the presence of hydrobromic acid in a 1 : 1 : 1 or 1 : 2 : 1 (TU : I2 : HBr) molar ratio. However, when the product of the reaction between TU and di-iodine in a 2 : 1 (TU : I2) molar ratio was crystallized in acetone-ethylether media the ionic salt of formula [(DAThdH(+))(I(-))] (6) (DAThd = 3,5-diamino-1,2,4-thiadiazole) was obtained. Methylthiourea (MeTU) reacted with di-iodine in the presence of hydrobromic acid (1 : 1 : 1, MeTU : I2 : HBr) in dichloromethane to form a solid product which gives [2(MeTU2) (2+)·(2Br(-))(I4(2-))] (7). Moreover, MeTU reacted with I2 in 2 : 1 (MeTU : I2) to form an intermediate powder product which was crystallized in acetone to give the 2-amino-3,4-dimethylthiazolium cation in [(DMeAThH(+))(I(-))(H2O)] (8). Upon changing the crystallization medium to ethanol, instead of acetone, the cationic 5-amino-3-methylamino-4-methyl-1,2,4-thiadiazolium (AMeAThdH)(+) in [(AMeAThdH(+))(I3(-))] (9) was formed. The compounds were characterized by m.p., FT-IR, UV-Vis, (1)H-NMR spectroscopy and mass spectrometry. The crystal structures of compounds 1-9 were determined by X-ray crystallography.

Synthesis, structural characterization and biological studies of the triphenyltin(IV) complex with 2-thiobarbituric acid.

The reaction between 2-thiobarbituric acid (H(2)TBA), which was treated with an equimolar amount of potassium hydroxide, in a water with triphenytin chloride in methanol, results in the formation of the {[Ph(3)Sn(O-HTBA)]}(n) (1) complex. Crystals of the hydrated 1 with formula {[Ph(3)Sn(O-HTBA)]·0.7(H(2)O)}(n) were growth from methanol/acetonitrile solution, of the white precipitation, filtered off, from the reaction. The crystal structure of complex 1 has been determined by X-ray diffraction at 120 K. Complex 1 is polymeric. The geometry around the tin(IV) ions is trigonal bi-pyramidal with coordination to three C atoms from phenyl groups and one O atom from a de-protonated HTBA ligand. Complex 1 and the already known [(n-Bu)(3)Sn(O-HTBA)·H(2)O] (2) were evaluated for their in vitro cytotoxic activity (cell viability) against human cancer cell lines: HeLa (cervical), OAW-42 (ovarian), MCF-7 (breast, ER positive), MDA-MB-231 (breast, ER negative), A549 (lung), Caki-1 (renal) and additionally, the normal human lung cell line MRC-5 (normal human fetal lung fibroblast cells) and normal immortalized human mammary gland epithelial cell line MTSV17 with a Trypan Blue assay. Moreover complex 1 was evaluated for its in vitro cell growth proliferation activity against leiomyosarcoma cells (LMS), MCF-7 and MRC-5 cells with a Thiazolyl Blue Tetrazolium Bromide (MTT) assay. The type of cell death caused by complexes 1 and 2 was also evaluated by use of flow cytometry assay. The results showed that these compounds mediate a strong cytotoxic response to normal and cancer cell lines tested through apoptosis and induce cell cycle arrest in S phase of the cell cycle, suggesting DNA intercalation (direct or indirect) with the complexes. Finally, the influence of these complexes 1 and 2 upon the catalytic peroxidation of linoleic acid to hydroperoxylinoleic acid by the enzyme lipoxygenase (LOX) was kinetically and theoretically studied.

Long-term culture of muscle explants from Sparus aurata.

Although there are mammalian myoblast cell lines, no fish myoblast cell line has been developed so far. The aim of this study was to develop a culture system of muscle explants for fish, as explants provide an approximation of the in vivo conditions for cell proliferation and differentiation, and enable a close comparison with events in muscle regenerating in vivo. Here we describe the main features of a long-term in vitro culture system for muscle explants from Sparus aurata fry. At the time of sampling, the original fibres were damaged and subsequently degenerated as shown by the loss of parvalbumin (PV) and presence of apoptotic nuclei. This mechanical damage provoked a myogenic response by activation of myogenic precursor cells. After a few days, new mononucleate cells aligned with the original fibres were seen in the explants, some with proliferating cell nuclear antigen (PCNA-) and Myf-5-positive nuclei, indicating proliferation and their myogenic fate. By 1 week, multinucleate cells with desmin immunoreactivity but PCNA- and Myf5-negative nuclei were present, equivalent to differentiated, postmitotic myotubes. Some of these myotubes were also immunoreactive for PV and insulin-like growth factors (IGFs). By 11 days, many of the myotubes were also immunoreactive for myostatin (MSTN). By 23 days, many of the myotubes had increased in diameter, were packed with myofibrils, and were strongly PV-positive and immunoreactive for MSTN, IGF-I and IGF-I receptor. This study shows that a proliferative process occurs in the explants despite the death of the original muscle fibres, and new muscle fibres expressing growth regulators are formed by regeneration from myogenic precursors present in the explants at the time of sampling.

Pre- and postoperative examinations in intestinal tumours of the pelvis.

Pre- and postoperative urological and lower urinary tract urodynamic studies were made in patients operated for intestinal tumours of the pelvis. It was established that urological complications often arise and they often escape detection during the examination or under the conventional surgical care. An examination and a control scheme is recommended for the early detection of the possible complications and for starting an adequate treatment in due time.