Experimental research was conducted to clarify the wettability alteration mechanism in the presence of metal cations. Wettability was studied by measuring the contact angle on a quartz–crude oil–water system. The quartz surface is aged in an asphaltene/toluene solution to study the effect of aging time, asphaltene concentration, water film on the quartz surface, and metal cations in the water film on wettability alteration of the quartz surface. The quartz surface property is characterized with ζ-potential measurements and infrared (IR) spectroscopy to clarify the wettability alteration mechanism. Results show that quartz surface becomes more oil-wet with the increase of the asphaltene concentration. The quartz with a pure water film shows less oil-wetting after soaking compared to the dry quartz surface, while the presence of metal cations in the water film can improve oil wettability of the surface. ζ-Potential measurements show that Ca2+ and Mg2+ compress a diffused double layer of quartz powder more effectively than Na+, which makes asphaltene adsorption easier because of the reduced electrostatic repulsion. IR spectra analysis indicates that asphaltene molecules can interact with hydroxyls on the quartz surface by polar interactions and asphaltene can be absorbed on the quartz surface with ion binding of hydrated divalent metal cations.

No abstract

Genetic polymorphism analysis for disease risk is widely used in epidemiology studies; blood or oral cavity cells are the most widely used source of DNA. However, these types of samples are not always available, particularly for studies that were conducted years ago. An alternative potential source of patient DNA exists in the form of paraffin-embedded normal tissue adjacent to tumor samples, which are collected and stored routinely for clinical use. The use of such samples can be conceptually problematic, however, due to the presence of field cancerization in the surrounding normal tissue, with the possible presence of chromosomal loss. Specifically, loss of heterozygosity (LOH) might bias the genotyping results and cause genotype misclassification. However, field cancerization and LOH might not be an issue because LOH is not easily found unless there is careful microdissection of only tumor cells (leaving stromal, inflammatory and fat cells), for example, laser-capture microdissection. In this study, we set out to determine the degree of genotype misclassification from normal tissues adjacent to tumors, if any, by comparing these results with blood genotyping. We examined samples from 106 subjects with breast cancer, analyzing five different genotypes selected from regions commonly known to have LOH in breast cancer. These genotypes were methylenetetrahydrofolate reductase (MTHFR), oxoguanosine glycosylase 1 (hOGG1), dopamine beta-hydroxylase (DBH), dopamine receptor D2 (DRD2) and NAD(P)H dehydrogenase quinone 1 (NQO1), conducted by using real-time PCR and TaqMan genotyping analyses. We found that among these five genotypes and 106 comparisons, there was a 100% concordance for genotyping from normal tissue adjacent to tumor and from blood. Our findings indicate that the use of adjacent normal tissues provides accurate genotyping results with high specificity. Although this study only used breast tumor samples, and may be applicable only to breast cancer studies, we expect the results to be applicable to other types of cancers also.

Iron deficiency anemia (IDA) is one of the most serious nutritional problems.

High expression of FGFR2 is correlated with advanced tumour stage, poor therapeutic response and worse survival in rectal cancer patients receiving neoadjuvant CCRT. These findings indicate that FGFR2 is a prognostic factor for treating rectal cancer.

Background: In vivo studies have recently demonstrated that interleukin 21 (IL-21) enhances the anti-tumor function of T-cells and NK cells in murine tumor models, and the combined use of IL-21 and IL-15 has resulted in prolonged tumor regression and survival in mice with previously established tumors. However, the combined anti-tumor effects of IL-21 and low dose IL-2 have not been studied even though IL-2 has been approved for human use, and, at low dose administration, stimulates the proliferation of memory T cells, and does not significantly increase antigen-induced apoptosis or regulatory T cell (Treg) expansion. This study examined whether recombinant IL-21 alone or in combination with low-dose IL-2 could improve the in vivo anti-tumor function of naïve, tumor-antigen specific CD8 + T cells in a gp100 [25][26][27][28][29][30][31][32][33] T cell receptor transgenic pmel murine melanoma model.

Abstract:The heterogeneous phase combination flooding (HPCF) system which is composed of a branched-preformed particle gel (B-PPG), polymer, and surfactant has been proposed to enhance oil recovery after polymer flooding in heterogeneous reservoirs by mobility control and reducing oil-water interfacial tension. However, the high cost of chemicals can make this process economically challenging in an era of low oil prices. Thus, in an era of low oil prices, it is becoming even more essential to optimize the heterogeneous phase combination flooding design. In order to optimize the HPCF process, the injection strategy has been designed such that the incremental oil recovery can be maximized using the corresponding combination of the B-PPG, polymer, and surfactant, thereby ensuring a more economically-viable recovery process. Different HPCF injection strategies including simultaneous injection and alternation injection were investigated by conducting parallel sand pack flooding experiments and large-scale plate sand pack flooding experiments. Results show that based on the flow rate ratio, the pressure rising area and the incremental oil recovery, no matter whether the injection strategy is simultaneous injection or alternation injection of HPCF, the HPCF can significantly block high permeability zone, increase the sweep efficiency and oil displacement efficiency, and effectively improve oil recovery. Compared with the simultaneous injection mode, the alternation injection of HPCF can show better sweep efficiency and oil displacement efficiency. Moreover, when the slug of HPCF and polymer/surfactant with the equivalent economical cost is injected by alternation injection mode, as the alternating cycle increases, the incremental oil recovery increases. The remaining oil distribution at different flooding stages investigated by conducting large-scale plate sand pack flooding experiments shows that alternation injection of HPCF can recover more remaining oil in the low permeability zone than simultaneous injection. Hence, these findings could provide the guidance for developing the injection strategy of HPCF to further enhance oil recovery after polymer flooding in heterogeneous reservoirs in the era of low oil prices.

Polymer gel treatment is a proven cost-effective method to control excessive water production and improve sweep efficiency in many mature oilfields; however, it is worth noting that there exist differences between gelation behavior and morphology in bulk and porous media, which are directly related to the success of a gel treatment. In this study, the gelation behavior and morphology of resorcinol-hexamethylenetetramine-HPAM gel in bulk and porous media were studied. Results revealed that the differences between the gelation time and morphology in bulk and porous media were obvious. The relationship between bulk gelation time and static gelation time in porous media was correlated. Dynamic gelation behavior in porous media confirmed that the gelation could occur during flow in porous media and the gelation location can be inferred to determine gel placement. This study could provide the basis for determining well shutoff time and understanding the blocking mechanism in porous media.