An in vitro evaluation of effectiveness of Xylene, Thyme oil and Orange oil in dissolving three different endodontic sealers

Aims

The aim of the study is to compare the dissolution effectiveness of xylene, thyme oil, and orange oil on three different endodontic sealers.

Materials and Methods

Standardized stainless steel molds were used to prepare 210 samples (70 for each endodontic sealer). The samples were divided into three groups based on sealers. Three experimental groups with 20 samples each were immersed in organic solvents. One control group of 10 samples was immersed in distilled water. Each group was further subdivided into two subgroups based on immersion time (2 and 10 min). Inferential statistics included one-way ANOVA, post hoc Tukey, and paired t-test.

Results

Thyme showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer whereas this difference was nonsignificant for Roekoseal and MTA Fillapex. Orange oil showed significantly more dissolution at 10 min compared to 2 min in dissolving AH Plus sealer and Roekoseal whereas this difference was nonsignificant concerning MTA Fillapex. Xylene showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer, Roekoseal, and MTA Fillapex.

Conclusions

Among the three solvents, xylene showed the highest dissolution of all three sealers. Orange oil was superior to thyme oil in dissolving the sealers. All the sealers showed more dissolution in all the solvents at 10 min compared to 2 min.

Structural analysis and ensemble docking revealed the binding modes of selected progesterone receptor modulators

Uterine fibroids (UF) are benign smooth muscle neoplasm of uterus that have a significant impact on a woman's quality of life as they perturb hormonal homeostasis resulting in heavy menstrual bleeding, impaired fertility, pregnancy complications and loss. UF can be surgically removed through invasive procedures, but their recurrence rate is often high. Progesterone receptor (PR) has an imperative role in UF management. Mifepristone, ulipristal acetate (UPA) and asoprisnil (ASO) are some selective progesterone receptor modulators (SPRMs), acts on PR, but due to their side effects in long term use, they were withdrawn from the market. Hence, there is a dire need for novel, highly efficient with least side effects, therapeutics for the treatment of UF. To contribute toward the drug discovery for UF, we made an extensive structural comparison of reported PR crystal structures, also elucidated the binding modes of four existing SPRMs against human PR through ensemble docking approach. Our studies revealed the presence of 5 highly repeating water molecules that has an important role in ligand binding and structural stability. Our ensemble docking and MD simulation revealed that studied ligands have preferential selectivity toward the specific conformation of PR. It is anticipated that our study will be a useful resource to all the drug discovery scientists who are engaged in the identification of lead molecules against UF.

Binding of rosmarinic acid curcumin and capsaicin with PLA2: A comparative study

Phospholipase A2 (PLA2) is a key enzyme involved in the formation of pro-inflammatory mediators like eicosanoids. Inhibition of PLA2 is regarded as one of the effective methods of controlling inflammation. The present study investigated the binding potentials of three natural compounds, rosmarinic acid (RA), capsaicin (CAP), and curcumin (CUR) by means of in silico and in vitro methods. Our study revealed that RA has relatively better binding affinity and inhibition potentials when compared to the other two molecules. Our ITC experiments were also suggested a slightly better binding energy for the RA. The stoichiometry of the protein ligand complex obtained from one of the ITC experiments suggested the possibilities of binding of a small molecule MCW (degraded product of CUR) on PLA2. Overall study demonstrated that the anti-inflammatory activity of RA, CUR and CAP may be partly due to the inhibition of PLA2.

AUTOMATIC OPTIMIZED CNN BASED COVID-19 LUNG INFECTION SEGMENTATION FROM CT IMAGE

In early 2020, the corona virus disease (COVID-19) has become a global epidemic. The WHO announced the disease as a public health emergency of international importance (PHEIC), and the issue was considered a health emergency. Automated computed tomography (CD) detection of lung infections offers a tremendous opportunity to expand the traditional health approach to resolving COVID-19. But many problems with CT. Facing contaminated areas from fragments, which include greater variability in infectious properties and low-intensity comparison between infections and normal tissues. Moreover, by suppressing the project of an in-depth model, a lot of information cannot be collected over some time.

Crystal structure of (E)-N'-(5-bromo-2-hy-droxy-benzyl-idene)nicotinohydrazide monohydrate

In the title compound, C13H10BrN3O2·H2O, the conformation about the azomethine double bond is E. The mol-ecule exists in the amido form with a C=O bond length of 1.229 (2) Å. There is an intra-molecular O-H⋯N hydrogen bond forming an S(6) ring motif. The whole mol-ecule is almost planar, with an r.m.s. deviation of 0.021 Å for all non-H atoms, and the dihedral angle between the planes of the pyridine and benzene rings is 0.74 (12)°. In the crystal, the water mol-ecule of crystallization links the organic mol-ecules via Ow-H⋯O, Ow-H⋯N and N-H⋯Ow hydrogen bonds and short C-H⋯Ow contacts, forming sheets lying parallel to (100). Within the sheets there is a weak π-π inter-action involving the pyridine and benzene rings [centroid-to-centroid distance = 3.8473 (15) Å]. The sheets are linked via C-H⋯Br inter-actions, forming a three-dimensional network.

Synthesis and spectral characterization of mono- and binuclear copper(II) complexes derived from 2-benzoylpyridine-N⁴-methyl-3-thiosemicarbazone: crystal structure of a novel sulfur bridged copper(II) box-dimer

Mononuclear and binuclear copper(II) complexes of 2-benzoylpyridine-N(4)-methyl thiosemicarbazone (HL) were prepared and characterized by a variety of spectroscopic techniques. Structural evidence for the novel sulfur bridged copper(II) iodo binuclear complex is obtained by single crystal X-ray diffraction analysis. The complex [Cu2L2I2], a non-centrosymmetric box dimer, crystallizes in monoclinic C2/c space group and it was found to have distorted square pyramidal geometry (Addison parameter, τ=0.238) with the square basal plane occupied by the thiosemicarbazone moiety and iodine atom whereas the sulfur atom from the other coordinated thiosemicarbazone moiety occupies the apical position. This is the first crystallographically studied system having non-centrosymmetrical entities bridged via thiolate S atoms with Cu(II)I bond. The tridentate thiosemicarbazone coordinates in mono deprotonated thionic tautomeric form in all complexes except in sulfato complex, [Cu(HL)(SO4)]·H2O (1) where it binds to the metal centre in neutral form. The magnetic moment values and the EPR spectral studies reflect the binuclearity of some of the complexes. The spin Hamiltonian and bonding parameters are calculated based on EPR studies. In all the complexes g||>g⊥>2.0023 and the g values in frozen DMF are consistent with the d(x2-y2) ground state. The thermal stabilities of some of the complexes were also determined.

N'-[(E)-1-(2-Fluoro-phen-yl)ethyl-idene]pyridine-4-carbohydrazide

The title compound, C₁₄H₁₂FN₃O, adopts an E conformation with respect to the azomethine bond. The pyridyl and fluoro­benzene rings make dihedral angles of 38.58 (6) and 41.61 (5)° respectively with the central C(=O)N₂CC unit, resulting in a non-planar mol­ecule. The inter­molecular inter­actions comprise two classical N—H⋯O and N—H⋯N hydrogen bonds and four non-classical C—H⋯O and C—H⋯F hydrogen bonds. These inter­actions are augmented by a weak π–π inter­action between the benzene and pyridyl rings of neighbouring mol­ecules, with a centroid–centroid distance of 3.9226 (10) Å. This leads to a three-dimensional supra­molecular assembly in the crystal system. The F atom is disordered over two sites in a 0.559 (3): 0.441 (3) ratio, through a 180° rotation of the fluoro­benzene ring.

N'-[(1E)-1-(2-Fluoro-phen-yl)ethyl-idene]pyridine-3-carbohydrazide

The title compound, C14H12FN3O, adopts an E conformation with respect to the azomethine double bond whereas the N and methyl C atoms are in a Z conformation with respect to the same bond. The ketonic O and azomethine N atoms are cis to each other. The non-planar mol-ecule [the dihedral angle between the benzene rings is 7.44 (11)°] exists in an amido form with a C=O bond length of 1.221 (2) Å. In the crystal, a bifurcated N-H⋯(O,N) hydrogen bond is formed between the amide H atom and the keto O and imine N atoms of an adjacent mol-ecule, leading to the formation of chains propagating along the b-axis direction. Through a 180° rotation of the fluoro-phenyl ring, the F atom is disordered over two sites with an occupancy ratio of 0.632 (4):0.368 (4).

N'-[(E)-2-Fluoro-benzyl-idene]benzo-hydrazide

The asymmetric unit of the title compound, C₁₄H₁₁FN₂O, contains two independent mol­ecules, both of which adopt the E conformation with respect to the azomethine C=N bond. The mol­ecules are non-planar, with dihedral angles of 26.92 (12) and 11.36 (11)° between the benzene and phenyl rings. In the crystal, mol­ecules are linked through N—H⋯O=C and N—H⋯N hydrogen bonds into chains along [101]. C—H⋯O contacts link these chains into layers parallel to (001). The three-dimensional crystal packing is stabilized by π–π inter­actions, the shortest separation between the centroids of benzene rings being 3.884 (1) Å.

Di-chlorido-{2-[(E)-phen-yl(pyridin-2-yl-κN)methyl-idene]-N-phenyl-hydra-zine-carboxamide-κ(2) N (2),O}copper(II)

The title compound, [CuCl2(C19H16N4O)], contains a Cu(II) atom N,N',O-chelated by a neutral N-phenyl-hy-dra-zine-car-box-amide ligand and additionally coordinated by two Cl atoms, resulting in a distorted square-pyramidal geometry. The ligating atoms in the basal square plane of the complex comprise the azomethine N, the pyridine N, the amide O and one of the Cl atoms, whereas the other Cl atom occupies an apical position. The apical Cl atoms in adjacent layers function as hydrogen-bond acceptors to both NH groups. Intermolecular C-H⋯Cl and C-H⋯O interactions are also observed.

Bis(1-phenyl-3-{(Z)-[phen-yl(pyridin-2-yl)methyl-idene]amino-κ²N,N'}urea-κO)nickel(II) dinitrate

The Ni(II) atom in the title salt, [Ni(C₁₉H₁₆N₄O)₂](NO₃)₂, is N,N',O-chelated by two neutral Schiff base ligands in a distorted octa-hedral geometry. One nitrate ion inter-acts with the metal atom indirectly, in an outer-sphere type of coordination, through N-H⋯O hydrogen bonds; the other nitrate ion does not engage in any inter-actions and is equally disordered over two positions in the crystal.