We investigate new symmetries which decouple the mass from the magnetic moment of neutrinos and their theoretical and phenomenological implications are discussed. Our proposed model is based on 𝑆𝑈 ( 2 ) 𝐻 horizontal symmetry that can generate large neutrino transition magnetic moment without inducing unacceptably large neutrino masses. In the 𝑆𝑈 ( 2 ) 𝐻 symmetric limit, the transition magnetic moment is nonzero, while the neutrino mass vanishes. The simplification we suggest is based on the symmetry being approximate, which we also generalize to a three-family 𝑆𝑈 ( 3 ) 𝐻 -symmetry. We have also investigated a spin symmetry mechanism that can generate large 𝜇 𝜈 while keeping 𝑚 𝜈 small. This talk is based on results obtained with K.S. Babu, and Manfred Lindner and presented in hep-ph 2007.04291 [1].
An array of self-assembled biocompatible doxorubicin (DOX) loaded heparin--cyclodextrin supramolecular hydrogels (DOX@HGs) with highly encapsulated efficiency was constructed using heparin-β-cyclodextrin derivatives (Hep-β-CD), α-cyclodextrin (α-CD), pluronic F-127 and DOX via the synergy of host-guest and multiple hydrogen bonding interactions. These hydrogels were characterized by GPC measurements (GPC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Size and zeta potential determinations, X-ray diffraction (XRD), and rheological characteristics; the data confirmed successful formation of the hydrogels. Furthermore, these hydrogels demonstrated distinctive thixotropy, indicating rapid self-repairing after continuously oscillatory shear stress. Variable release of DOX from DOX @HGs was obtained at various pH after 84 h depending on the strength of the hydrogels. At pH 7.4, cumulative DOX release was approximately 49.07% for DOX@HG 1, 32.15% for DOX@HG 2, and 27.12% for DOX@HG 3. While at pH 5.5, release of DOX was increased to 59.08% for DOX@HG 1 and to 43.2% for DOX@HG 3 after 84 h (P < 0.05). This information demonstrated that a higher DOX release rate was observed under a lower pH due to strong charge expansion of CDs and weakening of electrostatic interactions between heparin and DOX. Additionally, cytotoxicity of free DOX and DOX@HGs in ovarian cancer SKOV-3 cells was studied at various exposure durations. The results revealed that cytotoxicity of DOX@HG 1-3 toward ovarian cancer SKOV-3 cells was lower than that of free DOX (P < 0.05), suggesting prolonged DOX release from the hydrogels in SKOV-3 cells.
Rishav Chatterjee, Indira Bhattacharya, Souryadip Roy
et al.
Morpholine motif is an important pharmacophore and, depending on the molecular design, may localize in cellular acidic vesicles. To understand the importance of the presence of pendant morpholine in a metal complex, six bidentate N,O-donor ligands with or without a pendant morpholine unit and their corresponding ruthenium(II) p-cymene complexes (1-6) are synthesized, purified, and structurally characterized by various analytical methods including X-ray diffraction. Complexes 2-4 crystallized in the P21/c space group, whereas 5 and 6 crystallized in the P1̅ space group. The solution stability studies using 1H NMR support instantaneous hydrolysis of the native complexes to form monoaquated species in a solution of 3:7 (v/v) dimethyl sulfoxide-d6 and 20 mM phosphate buffer (pH* 7.4, containing 4 mM NaCl). The monoaquated complexes are stable for at least up to 24 h. The complexes display excellent in vitro antiproliferative activity (IC50 ca. 1-14 μM) in various cancer cell lines, viz., MDA-MB-231, MiaPaCa2, and Hep-G2. The presence of the pendant morpholine does not improve the dose efficacy, but rather, with 2-[[(2,6-dimethylphenyl)imino]methyl]phenol (HL1) and its pendant morpholine analogue (HL3) giving complexes 1 and 3, respectively, the antiproliferative activity was poorer with 3. MDA-MB-231 cells treated with the complexes show that the acidic vesicles remain acidic, but the population of acidic vesicles increases or decreases with time of exposure, as observed from the dispersed red puncta, depending on the complex used. The presence of the 2,6-disubstituted aniline and the naphthyl group seems to improve the antiproliferative dose. The complex treated MDA-MB-231 cells show that cathepsin D, which is otherwise present in the cytosolic lysosomes, translocates to the nucleus as a result of exposure to the complexes. Irrespective of the presence of a morpholine motif, the complexes do not activate caspase-3 to induce apoptosis and seem to favor the necrotic pathway of cell killing.