Cross-sectional observational study on accessory ostium of the maxillary sinus

Background: The association between chronic sinusitis and accessory ostium (AO) is still a controversial subject as previous studies have given variable results with wider range. Methods: Present study was designed to study the prevalence of AO in those with chronic sinusitis and those without the disease; 83 chronic rhinosinusitis (CRS) patients and 83 subjects without the disease were examined by diagnostic nasal endoscopy for the presence of accessory maxillary ostium. Results: Of the 83 CRS patients, 29% had an AO, whereas only 11% without the disease had it (P < 0.001). Most of the AOs were on the left side, especially in the posterior nasal fontanelle, in both groups. One unexposed subject and 5 patients had AOs on both sides. Double ostia were seen in 2% of CRS patients. However, symptoms such as facial pain, headache, purulence on examination, halitosis and post-nasal drip were found to have no specific association with the presence of AOs. Conclusions: The presence of an AO can be considered an indicator of the maxillary sinus disease, along with the other criteria for chronic sinusitis

Assessing Photosensitizer Targeting Using Meso-Tetra(Carboxyphenyl) Porphyrin

Mesotetra(4-carboxyphenyl)porphyrin (mTCPP) is a commercially available small molecule fluorophore and photosensitizer with four free carboxylic acid groups. mTCPP can readily be conjugated with amines for facile attachment of functional groups. In this work, we synthesized and assessed tetravalent, lysine-conjugated mTCPP, for its potential applications in targeted imaging and photodynamic therapy. Fmoc-protected d-lysine or l-lysine was conjugated to mTCPP via amide coupling with the epsilon amine group of lysine, followed by Fmoc deprotection. The resulting compounds did not dissolve well in aqueous solvent, but could be solubilized with the assistance of surfactants, including cholic acid. The l-amino acid transporter (LAT1) can uptake diverse neutral l-amino acids. In vitro studies with U87 cells revealed a non-specific uptake of the hydrophobic Fmoc-protected lysine-conjugated mTCPP precursors, but not d- or l-lysine mTCPP. Likewise, only the Fmoc-protected compounds induced substantial phototoxicty in cells following incubation and irradiation with blue light. These experimental results do not provide evidence to suggest that lysine-mTCPP is able to specifically target cancer cells. However, they do highlight mTCPP as a convenient and accessible framework for assessing molecular targeting of photosensitizers

Cleavage of proteins by a mixed-ligand copper(ii) phenolate complex: hydrophobicity of the diimine coligand promotes cleavage

The mixed-ligand copper(II) complex [Cu(tdp)(tmp)](ClO4), where H(tdp) is 2-[(2-(2-hydroxyethylamino)ethylimino)methyl]phenol and tmp is 3,4,7,8-tetramethyl-1,10-phenanthroline, exhibits cleavage of the proteins bovine serum albumin and lysozyme, producing approximately 5 and 4 kDa protein fragments respectively within a few minutes at micromolar concentrations. The hydrophobic tmp ligand recognizes the hydrophobic site and enhances protein binding and cleavage even at physiological pH and temperature

Interaction of rac-[Ru(5,6-dmp)<SUB>3</SUB>]<SUP>2+</SUP> with DNA: enantiospecific DNA binding and ligand-promoted exciton coupling

The X-ray crystal structure of the complex rac-[Ru(5,6-dmp)3]Cl2 (5,6-dmp = 5,6-dimethyl-1,10-phenanthroline) reveals a distorted octahedral coordination geometry with the Ru-N bond distances shorter than in its phen analogue. Absorption spectral titrations with CT DNA reveal that rac-[Ru(5,6-dmp)3]2+ interacts (Kb, (8.0 &#177; 0.2) &#215; 104 M-1) much more strongly than its phen analogue. The emission intensity of the 5,6-dmp complex is dramatically enhanced on binding to DNA, which is higher than that of the phen analogue. Also, interestingly, time-resolved emission measurements on the DNA-bound complex shows biexponential decay of the excited states with the lifetimes of short- and long-lived components being higher than those for the phen analogue. The CD spectral studies of rac-[Ru(5,6-dmp)3]2+ bound to CT DNA provide a definite and elegant evidence for the enantiospecific interaction of the complex with B-form DNA. Competitive DNA binding studies using rac-[Ru(phen)3]2+ provide support for the strong binding of the complex with DNA. The &#916;-enantiomer of rac-[Ru(5,6-dmp)3]2+ binds specifically to the right-handed B-form of poly d(GC)12 at lower ionic strength (0.05 M NaCl), and the &#923;-enantiomer binds specifically to the left-handed Z-form of poly d(GC)12 generated by treating the B-form with 5 M NaCl. The strong electronic coupling of the DNA-bound complex with the unbound complex facilitates the change in its enantiospecificity upon changing the conformation of DNA. The 1H NMR spectra of rac-[Ru(5,6-dmp)3]2+ bound to poly d(GC)12 reveal that the complex closely interacts most possibly in the major grooves of DNA. Electrochemical studies using ITO electrode show that the 5,6-dmp complex stabilizes CT DNA from electrocatalytic oxidation of its guanine base more than the phen analogue does

[Ru(phen)<SUB>2</SUB>(dppz)]<SUP>2+</SUP> as an efficient optical probe for staining nuclear components

The 'molecular light switch' complexes [Ru(bpy)2(dppz)]2+ (1) and [Ru(phen)2(dppz)]2+ (2), where bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline and dppz = dipyrido[3,2-a:2',3'-c]phenazine, have been explored as probes for diagnosing and staining nuclear components. The phen complex acts as a better staining agent for nonviable cells than for viable cells and exhibits a staining efficiency in tail region of comet more specific and stronger than the already known dye Hoechst 33258

Synthesis, characterization and DNA-binding properties of rac-[Ru(5,6-dmp)<SUB>2</SUB>(dppz)]<SUP>2+</SUP> - enantiopreferential DNA binding and co-ligand promoted exciton coupling

The new mixed ligand complex [Ru(5,6-dmp)2(dppz)]Cl2 [5,6-dmp = 5,6-dimethyl-1,10-phenanthroline, dppz = dipyrido[3,2-a:2',3'-c]phenazine] has been isolated and its DNA-binding properties studied by employing UV-visible (UV-Vis), steady-state and time-resolved emission and circular dichroism spectral methods, viscometry, thermal denaturation and cyclic/differential pulse voltammetric techniques. The complex acts as a 'molecular light-switch' on binding to DNA, but the enhancement in emission intensity is only 75% of that of the parent complex [Ru(phen)2(dppz)]2+ (phen = 1,10-phenanthroline). The emission decay curves and quenching studies suggest two different DNA-binding modes both involving intercalation of the dppz ligand of [Ru(5,6-dmp)2(dppz)]Cl2. The characteristic red-shift of the induced CD signal, which is not observed for the phen analogue, arises from exciton coupling. The hydrophobicity and polarizability of 5,6-dmp co-ligand strongly favour the formation of a stable structural and electronic scaffold on the DNA surface for the unbound molecules to couple with the DNA-bound complexes facilitating spontaneous assembly of novel extended molecular aggregates using DNA as a helical nanotemplate. This observation is consistent with the shift in Ru(II)/Ru(III) redox potential to more positive values with a dramatic drop in peak current on binding of the 5,6-dmp complex to calf thymus (CT) DNA. Equilibrium dialysis experiments monitored by CD spectroscopy unambiquously reveal the preferential binding of the &#916;-enantiomer to the right-handed calf thymus (CT) DNA. The 5,6-dmp complex exhibits preferential binding to [d(AT)6]2 over [d(GC)6]2 and the complex aggregates formed consist of six [Ru(5,6-dmp)2(dppz)]2+ cations per base pair of [d(AT)6]2; however, only one [Ru(phen)2(dppz)]2+ cation per base pair is involved in DNA binding

Enantiopreferential DNA binding: [{(5,6-dmp)<SUB>2</SUB>ru}<SUB>2</SUB>( &#956; -bpm)]<SUP>4+</SUP> induces a B-to-Z conformational change on DNA

The dinuclear ruthenium(II) complex [{(5,6-dmp)2Ru}2(&#956; -bpm)]4+ (5,6-dmp = 5,6-dimethyl-1,10-phenanthroline; bpm = 2,2'-bipyrimidine) was synthesized and the meso (&#916;&#923;) and rac (&#916;&#916;, &#923;&#923;) diastereoisomers separated using cation-exchange chromatography, and characterized using CHN analysis as well as UV-visible and 1H NMR spectra. The rac form was interacted with calf thymus DNA (CT DNA) and certain selected dodecanucleotides, like poly d(GC)12 and poly d(AT)12 and the hexanucleotide d(GTCGAC)2. Absorption, emission and circular dichroic spectral techniques, DNA melting studies and viscometry were used to monitor the interactions. Induced biphasic CD signals due to exciton coupling between dinuclear complexes bound on the DNA nanotemplate and the complexes free in solution were observed in the UV region. In contrast, the mononuclear analogue rac-[Ru(5,6-dmp)2(bipy)]2+ did not show any biphasic CD signal upon an interaction with DNA under identical conditions. An increase in the ionic strength of the buffer and a decrease in the length of the DNA lowered the extent of exciton coupling. Also, the complex preferentially bound to GC, rather than the AT sequence, as revealed from the higher intensity of the biphasic CD signal for the former. An equilibrium dialysis experiment unambiquously revealed the preferential binding of &#916;&#916;-enantiomer to CT DNA, and also its potential, interestingly, to induce a B-to-Z conformational change on DNA. The latter was confirmed by the 31P NMR spectra of poly d(GC)12 bound to the dinuclear complex. A DNA binding model involving the partial insertion of one of the 5,6-dmp ligands of the large dinuclear complex (&#916;&#916;-enantiomer) between the DNA base pairs in the minor groove was suggested using molecular modeling; this model is preferred over one involving simple, electrostatic groove binding. This is supported by viscometry studies, which indicate an enhancement in the relative viscosity of CT DNA upon an interaction with the dinuclear complex

Mixed ligand ruthenium(II) complexes of bis(pyrid-2-yl)-/bis(benzimidazol-2-yl)-dithioether and diimines: study of non-covalent DNA binding and cytotoxicity

A series of mixed ligand ruthenium(II) complexes [Ru(pdto)(diimine)](ClO4)2/(PF6)21-3 and [Ru(bbdo)(diimine)](ClO4)24-6, where pdto is 1,8-bis(pyrid-2-yl)-3,6-dithiooctane, bbdo is 1,8-bis(benzimidazol-2-yl)-3,6-dithiooctane and diimine is 1,10-phenanthroline (phen), dipyrido-[3,2-d:2',3'-f]-quinoxaline (dpq) and dipyrido[3,2-a:2',3'-c]phenazine (dppz), have been isolated and characterised by analytical and spectral methods. The complexes [Ru(pdto)(phen)](PF6)21a, [Ru(pdto)(dpq)(Cl)](PF6) 2a, [Ru(bbdo)(phen)](PF6)24a and [Ru(bbdo)(dpq)](ClO4)25 have been structurally characterized and their coordination geometries around ruthenium(II) are described as distorted octahedral. In 1a, 4a and 5 the two thioether sulfur and two py/bzim nitrogen atoms of the tetradentate pdto/bbdo ligand are folded around Ru(II) to give predominantly a "cis-&#945;" configuration. IH NMR spectral data of the complexes support this configuration in solution. In [Ru(pdto)(dpq)Cl](PF6) 2a with a distorted octahedral coordination geometry, one of the two py nitrogens of pdto is not coordinated. The DNA binding constants (Kb: 2, 2.00 &#177; 0.02 &#215; 104 M-1, s = 1.0; 3, 3.00 &#177; 0.01 &#215; 106 M-1, s = 1.3) determined by absorption spectral titrations of the complexes with CT DNA reveal that 3 interacts with DNA more tightly than 2 through partial intercalation of the extended planar ring of coordinated dppz with the DNA base stack. The DNA binding affinities of the complexes increase with increase in the number of planar aromatic rings in the co-ligand, and on replacing both the py moieties in pdto complexes (1-3) by bzim moieties to give bbdo complexes (4-6). Upon interaction with CT DNA the complexes 1, 2, 5 and 6 show a decrease in anodic current in the cyclic voltammograms. On the other hand, interestingly, 3 and 4 show an increase in anodic current suggesting their involvement in electrocatalytic guanine oxidation. Interestingly, of all the complexes, only 6 alters the superhelicity of DNA upon binding with supercoiled pBR322 DNA. The cytotoxicities of the dppz complexes 3 and 6, which avidly bind to DNA, have been examined by screening them against cell lines of different cancer origins. It is noteworthy that 6 exhibits selectivity with higher cytotoxicity against the melanoma cancer cell line (A375) than other cell lines, potency approximately twice that of cisplatin and toxicity to normal cells 3 and 90 times less than cisplatin and adriamycin respectively

Mixed ligand ruthenium(II) complexes of bis(pyrid-2-yl)-/bis(benzimidazol-2-yl)-dithioether and diimines: Study of non-covalent DNA binding and cytotoxicity

A series of mixed ligand ruthenium(II) complexes [Ru(pdto)(diimine)]$(ClO_4)_2/(PF_6)_2$ 1–3 and [Ru(bbdo)(diimine)]$(ClO_4)_2$ 4–6, where pdto is 1,8-bis(pyrid-2-yl)-3,6-dithiooctane, bbdo is 1,8-bis(benzimidazol-2-yl)-3,6-dithiooctane and diimine is 1,10-phenanthroline (phen), dipyrido-[3,2-d:2,3-f]-quinoxaline (dpq) and dipyrido[3,2-a:2,3-c]phenazine (dppz), have been isolated and characterised by analytical and spectral methods. The complexes [Ru(pdto)(phen)]$(PF_6)_2$ 1a, [Ru(pdto)(dpq)(Cl)]$(PF_6)$ 2a, [Ru(bbdo)(phen)]$(PF_6)_2$ 4a and [Ru(bbdo)(dpq)]$(ClO_4)_2$ 5 have been structurally characterized and their coordination geometries around ruthenium(II) are described as distorted octahedral. In 1a, 4a and 5 the two thioether sulfur and two py/bzim nitrogen atoms of the tetradentate pdto/bbdo ligand are folded around Ru(II) to give predominantly a cis- configuration. IH NMR spectral data of the complexes support this configuration in solution. In [Ru(pdto)(dpq)Cl]$(PF_6)$ 2a with a distorted octahedral coordination geometry, one of the two py nitrogens of pdto is not coordinated. The DNA binding constants $(Kb: 2, 2.00 \pm 0.02 X 104 M^{-1}, s = 1.0; 3, 3.00 \pm 0.01 X 106 M^{-1}, s = 1.3)$ determined by absorption spectral titrations of the complexes with CT DNA reveal that 3 interacts with DNA more tightly than 2 through partial intercalation of the extended planar ring of coordinated dppz with the DNA base stack. The DNA binding affinities of the complexes increase with increase in the number of planar aromatic rings in the co-ligand, and on replacing both the py moieties in pdto complexes (1–3) by bzim moieties to give bbdo complexes (4–6). Upon interaction with CT DNA the complexes 1, 2, 5 and 6 show a decrease in anodic current in the cyclic voltammograms. On the other hand, interestingly, 3 and 4 show an increase in anodic current suggesting their involvement in electrocatalytic guanine oxidation. Interestingly, of all the complexes, only 6 alters the superhelicity of DNA upon binding with supercoiled pBR322 DNA. The cytotoxicities of the dppz complexes 3 and 6, which avidly bind to DNA, have been examined by screening them against cell lines of different cancer origins. It is noteworthy that 6 exhibits selectivity with higher cytotoxicity against the melanoma cancer cell line (A375) than other cell lines, potency approximately twice that of cisplatin and toxicity to normal cells 3 and 90 times less than cisplatin and adriamycin respectively