Bougainvillea glabra-mediated synthesis of Zr₃O and chitosan-coated zirconium oxide nanoparticles: Multifunctional antibacterial and anticancer agents with enhanced biocompatibility.

The effectiveness and safety of nanomaterials (NMs) are essential for their use in healthcare. This study focuses on creating NPs with multifunctional antibacterial and anticancer properties to combat bacterial infections and cancer disease more effectively than traditional antibiotics. This study investigates the synthesis of ZrO and chitosan (ch) coated zirconium oxide nanoparticles (chZrO NPs) using Bougainvillea glabra (B.

Age Estimation with Cemental Annulation Using Light, Phase Contrast and Polarized Microscopy.

Introduction: In forensic science, the determination of age plays a vital role in the identification of bodies and persons associated with crimes. Teeth are frequently better conserved than any other human remains, so their use for identifying age at death is vital. The root portion of the teeth is covered by a thin calcified layer called cementum, the annulations of which is considered to be helpful in age estimation.

Morphometric computer-assisted image analysis of epithelial cells in different grades of oral squamous cell carcinoma.

Introduction: Oral squamous cell carcinoma (OSCC) accounts 94% of all malignant lesions in the oral cavity. In the assessment of OSCC, nowadays the WHO grading system has been followed widely but due to its subjectivity, investigators applied the sophisticated technique of computer-assisted image analysis in the grading of carcinoma in larynx, lungs, esophagus, and cervix to make it more objective.

Aims And Objectives: Access, analyze, and compare the cellular area (CA); cytoplasmic area (Cyt A); nuclear area (NA); nuclear perimeter (NP); nuclear form factor (NF); and nuclear-cytoplasmic ratio (N/C) of the cells in different grades of OSCC.

Study of Collagen Birefringence in Different Grades of Oral Squamous Cell Carcinoma Using Picrosirius Red and Polarized Light Microscopy.

Objectives. The present study was done to evaluate birefringence pattern of collagen fibres in different grades of oral squamous cell carcinoma using Picrosirius red stain and polarization microscopy and to determine if there is a change in collagen fibres between different grades of oral squamous cell carcinoma. Materials and Methods.

Effects of tyrosine mutations on the conformational and oxidative folding of ribonuclease a: a comparative study.

Ribonuclease A (RNase A) undergoes more rapid conformational folding with its disulfide bonds intact than during oxidative folding from its reduced form. In this study, the effects of the mutants Y92G, Y92A, and Y92L on both the conformational and oxidative folding pathways were examined to determine the role of native interactions in different types of conformational searches for the biologically active structure of a protein. These mutations did not affect the overall conformational folding pathway of RNase A.

Implementation of a k/k(0) method to identify long-range structure in transition states during conformational folding/unfolding of proteins.

A previously introduced kinetic-rate constant (k/k(0)) method, where k and k(0) are the folding (unfolding) rate constants in the mutant and the wild-type forms, respectively, of a protein, has been applied to obtain qualitative information about structure in the transition state ensemble (TSE) of bovine pancreatic ribonuclease A (RNase A), which contains four native disulfide bonds. The method compares the folding (unfolding) kinetics of RNase A, with and without a covalent crosslink and tests whether the crosslinked residues are associated in the folding (unfolding) transition state (TS) of the noncrosslinked version. To confirm that the fifth disulfide bond has not introduced a significant structural perturbation, we solved the crystal structure of the V43C-R85C mutant to 1.

Oxidative folding and N-terminal cyclization of onconase.

Cyclization of the N-terminal glutamine residue to pyroglutamic acid in onconase, an anti-cancer chemotherapeutic agent, increases the activity and stability of the protein. Here, we examine the correlated effects of the folding/unfolding process and the formation of this N-terminal pyroglutamic acid. The results in this study indicate that cyclization of the N-terminal glutamine has no significant effect on the rate of either reductive unfolding or oxidative folding of the protein.

Diffusional barrier in the unfolding of a small protein.

To determine how the dynamics of the polypeptide chain in a protein molecule are coupled to the bulk solvent viscosity, the unfolding by urea of the small protein barstar was studied in the presence of two viscogens, xylose and glycerol. Thermodynamic studies of unfolding show that both viscogens stabilize barstar by a preferential hydration mechanism, and that viscogen and urea act independently on protein stability. Kinetic studies of unfolding show that while the rate-limiting conformational change during unfolding is dependent on the bulk solvent viscosity, eta, its rate does not show an inverse dependence on eta, as expected by Kramers' theory.

Correlation of folding kinetics with the number and isomerization states of prolines in three homologous proteins of the RNase family.

Several studies attribute the slower phases in protein folding to prolyl isomerizations, and several others do not. A correlation exists between the number of prolines in a protein and the complexity of the mechanism with which it folds. In this study, we have demonstrated a direct correlation between the number of cis-prolyl bonds in a native protein and the complexity with which it folds via slower phases by studying the folding of three structurally homologous proteins of the ribonuclease family, namely RNase A, onconase and angiogenin, which differ in the number and isomerization states of their proline residues.

Effect of salt on the urea-unfolded form of barstar probed by m value measurements.

To probe for residual structure present in the urea-unfolded form of the small protein barstar, to determine how salt might modulate such structure, and to determine how such structure might affect the stability of the protein, mutant variants that display m values different from that of the wild-type protein have been studied. The mutant proteins were obtained by site-directed mutagenesis at residue positions located on the surface of the folded protein. The m value, which represents the preferential free energy of interaction of urea with the unfolded form in comparison to that with the folded state, was determined from equilibrium urea-induced unfolding curves.

Osmolytes induce structure in an early intermediate on the folding pathway of barstar.

Osmolytes stabilize proteins against denaturation, but little is known about how their stabilizing effect might affect a protein folding pathway. Here, we report the effects of the osmolytes, trimethylamine-N-oxide, and sarcosine on the stability of the native state of barstar as well as on the structural heterogeneity of an early intermediate ensemble, IE, on its folding pathway. Both osmolytes increase the stability of the native protein to a similar extent, with stability increasing linearly with osmolyte concentration.

Differential salt-induced stabilization of structure in the initial folding intermediate ensemble of barstar.

The effects of two salts, KCl and MgCl(2), on the stability and folding kinetics of barstar have been studied at pH 8. Equilibrium urea unfolding curves were used to show that the free energy of unfolding, deltaG(UN), of barstar increased from a value of 4.7 kcalmol(-1) in the absence of salt to a value of 6.