Confined toluene within InOF-1: CO2 capture enhancement

The toluene adsorption properties of InOF-1 are studied along with the confinement of small amounts of this non-polar molecule revealing a 1.38-fold increase in CO₂ capture, from 5.26 wt% under anhydrous conditions to 7.28 wt% with a 1.5 wt% of pre-confined toluene at 298 K. The InOF-1 affinity towards toluene was experimentally quantified by ΔH_ads (−46.81 kJ mol⁻¹). InOF-1 is shown to be a promising material for CO₂ capture under industrial conditions. Computational calculations (DFT and QTAIM) and DRIFTs in situ experiments provided a possible explanation for the experimental CO₂ capture enhancement by showing how the toluene molecule is confined within InOF-1, which constructed a “bottleneck effect”.

The confinement of small amounts of toluene demonstrated an enhanced CO₂ capture for InOF-1 as a result of a bottleneck effect and synergistic interactions.     

Shorter telomeres and high telomerase activity correlate with a highly aggressive phenotype in breast cancer cell lines

Tumor Biology - Maintenance of telomere length is one function of human telomerase that is crucial for the survival of cancer cells and cancer progression. Both telomeres and telomerase have been...     

Non-covalent interactions between sertraline stereoisomers and 2-hydroxypropyl-β-cyclodextrin: a quantum chemistry analysis

Inclusion compounds formed between sertraline stereoisomers and β-cyclodextrin, and 2-hydroxypropyl-β-cyclodextrin, were analyzed by using quantum chemistry methods. The exploration of the potential energy surface was performed using chemical intuition and classical molecular mechanics. This approach delivered around 200 candidates for low energy adducts, which were optimized through the PBE0/6-31G(d,p) method, and after this process solvent effects were considered by the continuous solvent model. This analysis showed that β-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin are good trappers of sertraline, although the isomers suggested by molecular dynamics presented higher binding energies than those obtained by chemical intuition. The role of hydrogen bonds in the formation of adducts was studied using the non-covalent interactions index and the quantum theory of atoms in molecules. In this article we concluded that these interactions are present in all adducts, however, they are not important in the stabilization of these inclusion compounds. The molecular electrostatic potential indicates that Coulomb interactions could be responsible for the formation of these systems, although sophisticated solvent models must be used to confirm this conclusion, which are impractical in this case because of the sizes involved in these systems.

Inclusion compounds formed between sertraline stereoisomers and β-cyclodextrin, and 2-hydroxypropyl-β-cyclodextrin, were analyzed by using quantum chemistry methods.     

DNA damage in peripheral lymphocytes of untreated breast cancer patients

BACKGROUND: Using the alkaline comet assay, DNA single-strand breaks (ssb) have been described in peripheral blood lymphocytes (PBL) from breast cancer patients without treatment, but there is no information concerning the occurrence of double-strand breaks (dsb) in the same patients. The purpose of this study was to investigate whether PBL of untreated sporadic breast cancer patients harbor an elevated number of both DNA strand breaks. METHODS: Forty breast cancer patients without family history of cancer in clinical stage III devoid of treatment and 60 age-matched healthy subjects without history of breast cancer were included. PBL from freshly drawn blood were processed following two different methods: the alkaline and the neutral comet assay. Percentage and tail moment were assessed under fluorescence microscopy and a computer-based image analysis system. RESULTS: In controls, ssb were found in 18 +/- 4.67% of PBL, and dsb at 7.99 +/- 3.67% of PBLs. Cancer patients had higher values of both ssb 24.08 +/- 4.96 (p <0.05) and dsb 13.11 +/- 3.2% (p <0.01). Tail moment for ssb was 6.23 +/- 1.44 and dsb, 2.31 +/- 1.09 for controls. For breast cancer patients, tail moment for ssb was 11.73 +/- 2.40 and for dsb, 6.33 +/- 1.75 (p <0.01). On plotting individual measurements of comet percentage against tail moment for alkaline and neutral comet assays, clear separation of control group from cancer patients can be seen in both assays. CONCLUSIONS: Demonstration of two types of DNA damage in PBL of breast cancer patients devoid of treatment or without exposure to environmental genotoxic agents provides a better picture of the degree of DNA damage present in somatic cells of these patients.     

Nuclear co-expression of p14ARF and p16INK4A in uterine cervical cancer-derived cell lines containing HPV

The Papanicolaou test (Pap) has been responsible for a significant reduction of cervical cancer-related morbimortality. In order to increase its sensitivity and specificity new markers have been studied and incorporated to cytological and histological methods for diagnosis for cervical cancer, such as p16INK4A that has been considered the immunocytochemical marker of choice for detection of HPV related cancers. We considered that p14ARF could be a complementary marker in order to improve the accuracy of cytological diagnosis because its genetic proximity to p16INK4A. We performed a systematic analysis of several putative cervical cancer markers in order to evaluate their performance in the detection of malignancy, in comparison with p16INK4A and p14ARF, using immunocytochemistry (ICC), immunofluorescence (IF) and Western blot analyses. Most markers were non-specific and could not discriminate HPV infected cancer cell lines from other non HPV malignant. In contrast, nuclear co-expression of p16INK4A and p14ARF was observed only in HPV-transformed cancer cell lines. Notably, in C-33A cervical cancer cells (HPV negative), p14ARF was present in the nucleoli, but p16INK4A was conspicuously absent from the nuclei of these cells. We conclude that both markers; p16INK4A and p14ARF are complementary and should be evaluated jointly in order to improve the accuracy of cytological diagnosis of cervical cancer.