An analytical solution of the diffusion- convection equation over a finite domain

Numerical solutions to the diffusion-convection equation are usually evaluated through comparison with analytical solutions in one dimension. Literature survey indicates the most frequently used analytical solution is one derived for asemi-infinite domain. This paper presents an analytical solution to this problem over a finite domain. Comparison is made with a solution to a mathematically similar problem in heat conduction with radiation.     

Protective effect of sanguinarine on ultraviolet B-mediated damages in SKH-1 hairless mouse skin: implications for prevention of skin cancer

Excessive exposure of solar ultraviolet (UV) radiation, particularly its UVB component (280-320 nm), to human skin is the major cause of skin cancers. UV exposure also leads to the development of precancerous conditions such as actinic keratosis and elicits a variety of other adverse effects such as sunburn, inflammation, hyperplasia, immunosuppression and skin aging. Therefore, there is a need to intensify our efforts towards the development of novel mechanism-based approaches/agents for the protection of UVB-mediated damages. Chemoprevention is being investigated as a potential approach for the management of UV damages including skin cancer. We have earlier shown that sanguinarine, a benzophenanthridine alkaloid, inhibits UVB exposure-mediated damages in HaCaT keratinocytes. In this study, to determine the relevance of our in vitro findings to in vivo situations, we assessed the effects of sanguinarine on UVB-mediated damages in SKH-1 hairless mice. Our data demonstrated that a topical application of sanguinarine (5 micromol 0.3 mL(-1) ethanol per mouse), either as a pretreatment (30 min prior to UVB) or posttreatment (5 min after UVB), resulted in a significant decrease in UVB-mediated increases in skin edema, skin hyperplasia and infiltration of leukocytes. Further, sanguinarine treatments (pre and post) also resulted in a significant decrease in UVB mediated (1) generation of H2O2 and (2) increases in the protein levels of markers of tumor promotion/proliferation viz. ornithine decarboxylase (ODC), proliferating cell nuclear antigen (PCNA) and Kiel antigen-67. Based on this data, we suggest that sanguinarine could be developed as an agent for the management of conditions elicited by UV exposure including skin cancer. However, further detailed studies are needed to support this suggestion.     

On dominant contractions and a generalization of the zero–two law

Zaharopol proved the following result: let \({T,S:L^1(X,{\mathcal{F}},\mu)\to L^1(X, {\mathcal{F}},\mu)}\) be two positive contractions such that T ≤ S. If \({\|S-T\| <1 }\) then \({\left\|S^n-T^n\right\| <1 }\) for all \({n\in\mathbb{N}}\). In the present paper we generalize this result to multi-parameter contractions acting on L ¹. As an application of that result we prove a generalization of the “zero–two” law.     

Saffron and Its Major Ingredients’ Effect on Colon Cancer Cells with Mismatch Repair Deficiency and Microsatellite Instability

Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. One of its subtypes is associated with defective mismatch repair (dMMR) genes. Saffron has many potentially protective roles against colon malignancy. However, these roles in the context of dMMR tumors have not been explored. In this study, we aimed to investigate the effects of saffron and its constituents in CRC cell lines with dMMR. Methods: Saffron crude extracts and specific compounds (safranal and crocin) were used in the human colorectal cancer cell lines HCT116, HCT116+3 (inserted MLH1), HCT116+5 (inserted MSH3), and HCT116+3+5 (inserted MLH1 and MSH3). CDC25b, p-H2AX, TPDP1, and GAPDH were analyzed by Western blot. Proliferation and cytotoxicity were analyzed by MTT. The scratch wound assay was also performed. Results: Saffron crude extracts restricted (up to 70%) the proliferation in colon cells with deficient MMR (HCT116) compared to proficient MMR. The wound healing assay indicates that deficient MMR cells are doing better (up to 90%) than proficient MMR cells when treated with saffron. CDC25b and TDP1 downregulated (up to 20-fold) in proficient MMR cells compared to deficient MMR cells, while p.H2AX was significantly upregulated in both cell types, particularly at >10 mg/mL saffron in a concentration-dependent manner. The reduction in cellular proliferation was accompanied with upregulation of caspase 3 and 7. The major active saffron compounds, safranal and crocin reproduced most of the saffron crude extracts’ effects. Conclusions: Saffron’s anti-proliferative effect is significant in cells with deficient MMR. This novel effect may have therapeutic implications and benefits for MSI CRC patients who are generally not recommended for the 5-fluorouracil-based treatment.     

Measurable bundles of C^*-dynamical systems and its applications

In the present paper we investigate \(L_0\) -valued states and Markov operators on \( C^*\) -algebras over \(L_0\) . Here, \(L_0=L_0(\Omega )\) is the algebra of equivalence classes of complex measurable functions on \((\Omega ,\Sigma ,\mu )\) . In particular, we give representations for \(L_0\) -valued states and Markov operators on \(C^*\) -algebras over \(L_0\) , respectively, as measurable bundles of states and Markov operators. Moreover, we apply the obtained representations to study certain ergodic properties of \( C^*\) -dynamical systems over \(L_0\) .     

Recent Advances in Transition Metal-Based Catalysts for Ethylene Copolymerization with Polar Comonomer

The synthesis of polar functionalized polyolefin (PFP) offers improvement in mixing properties, polymer surface, and rheological properties with the potential of upgraded polyolefins for modern and ingenious applications. The synthesis of PFP from metal-based catalyzed olefin (non-polar in nature) copolymerization with polar comonomers embodies energy-efficient, atom-efficient, and apparently an upfront methodology. Despite their outstanding success during conventional polymerization of olefin, 3^rd and 4^th group (early transition metal)-based catalysts, owing to their electrophilic nature, face challenges mainly due to Lewis basic sites of the polar monomers. On the contrary, late transition metal-based catalysts have also made progress, in recent years, for PFP synthesis. The recent past has also witnessed several advancements in the development of dominating palladium-based catalysts while their lower resistance towards ligand functional groups has limited the practical application of abundant and cheaper nickel-based catalysts. However, the relentless efforts of the scientific community, during the past half-decade, have indicated rigorous progress in the development of nickel-based catalysts for PFP synthesis. In this review, we have abridged the recent research trends in both early as well as late transition metal-based catalyst development. Furthermore, we have highlighted the role of transition metal-based catalysts in influencing the polymer properties.     

Catalytic protein modification with dirhodium metallopeptides: specificity in designed and natural systems

In this study, we present advances in the use of rhodium(II) metallopeptides for protein modification. Site-specific, proximity-driven modification is enabled by the unique combination of peptide-based molecular recognition and a rhodium catalyst capable of modifying a wide range of amino-acid side chains. We explore catalysis based on coiled-coil recognition in detail, providing an understanding of the determinants of specificity and culminating in the demonstration of orthogonal modification of separate proteins in cell lysate. In addition, the concepts of proximity-driven catalysis are extended to include modification of the natural Fyn SH3 domain with metallopeptides based on a known proline-rich peptide ligand. The development of orthogonal catalyst-substrate pairs for modification in lysate, and the extension of these methods to new natural protein domains, highlight the capabilities for new reaction design possible in chemical approaches to site-specific protein modification.     

In vitro Inhibition Effect of Transition Metal Ions on Succinate‐Fumarate System in ATP Cycle

Oxidation of sodium succinate in aqueous solution by potassium ferricyanide was investigated. The effects of different reaction parameters such as initial concentration of succinate, concentration of ferricyanide, and influence of metal ions (Zn⁺², Ni⁺², Cu⁺², Cd⁺²) on the oxidation of succinate were investigated at 25 ± 0.05 °C. Large rate enhancements were observed in the redox reaction between succinate and ferricyanide with increasing concentrations of both oxidant and reductant. The kinetics results indicated that the succinate oxidation was significantly inhibited in the presence of metal ions. Pseudo first order rate constants values were found decreased with increase in concentrations of metal ions which reflected that inhibition rate was directly influenced with the metal ions concentration.