The order of appearance of different genetic aberrations during the shift from diploidy/near-diploidy to aneuploidy in colorectal cancers is not yet clear. We studied genetic alterations in flow cytometrically-sorted DNA diploid and corresponding aneuploid epithelial cell populations from each of 20 colorectal tumors using comparative genomic hybridization, FISH, and PCR. Analysis of the 19 cases in which aberrations were found in the flow-sorted diploid population indicated that large-scale aneuploidization in colorectal cancer was preceded by amplification of oncogene(s) localized to chromosome 20q13.2 and by KRAS mutations, but not by TP53 deletions or losses of large chromosomal regions such as 4q, 8p and 18q. ' 2007 Wiley-Liss, Inc.Key words: DNA aneuploidy; DNA diploidy; flow-sorted colorectal tumors; CGH; chromosomal aberrations; FISH; 20q13 gain Colorectal tumorigenesis is characterized by the sequential accumulation of multiple and extensive genomic changes in normal colonic mucosal cells, 1 which ultimately lead to high-level aneuploidy in the majority of tumors. 2 The order of appearance of different genetic aberrations and the molecular mechanisms underlying the shift from diploidy to aneuploidy are not yet clear. The origin of high-level aneuploidy has been suggested to occur via tetraploidization of near-diploid aberrant colonic mucosal cells followed by chromosome loss. 3 Genes responsible for DNA double-strand break repair, chromosomal stability, chromosomal segregation and chromosome disjunction have also been suggested as likely candidates in the development of aneuploidy. 4,5 TP53 gene alterations may also be permissive for aneuploidy, 6 since the resulting loss of wild-type TP53 function may facilitate the formation and survival of cells with abnormal DNA content. Aneuploid colorectal tumors exhibit considerable chromosomal instability as evidenced by frequent gains of chromosomes 20 and 13 and frequent losses of chromosomes 18 and 4. 7,8 Late-stage colorectal adenomas harbor some of the same chromosomal aberrations as seen in colorectal carcinomas, although their incidence is less frequent. 7,9 The putative oncogenes and tumor suppressor genes localized to these frequently-amplified or -deleted chromosomal regions are still mostly unidentified.The resolution of flow cytometric DNA content measurements is limited to the detection of a variation in DNA content of about 5%. Thus cell populations with gain or loss of only 1 or 2 chromosomes may be measured by flow cytometry as having diploid DNA content, even if such near-diploid populations predominate in a cell sample. Flow cytometric DNA content histograms of aneuploid tumors typically show a cell population with ''diploid'' DNA content (Figure 1a). This DNA diploid cell population consists of infiltrating leucocytes and colonic mucosal cells. Some of these colonic mucosal cells may possibly be late-stage adenoma cells or abnormal cells (with some few chromosomal aberrations) that are at an early stage of tumor progression, and which may stil...

Paper mill workers are exposed to culturable microorganisms (MOs). We hypothesized that inflammatory airway response could be detected in sputum of nonsymptomatic workers. From four paper mills, we included 29 healthy nonsmoking men. Workers exposed to high levels of MOs (HMOE, n = 17) were compared with workers exposed to low levels of MO (LMOE, n = 12). A reference group of 22 healthy, nonsmoking, nonexposed (NE) men were also included. We performed differential cell counts of induced sputum, studied gene expressions of isolated sputum macrophages and analyzed inflammatory parameters, including matrix metalloproteinases. Sputum from HMOE workers had a significantly higher percentage of neutrophils than that from LMOE workers (P < 0.05) and NE controls (P < 0.001). There was also an increased gene expression of different pro-inflammatory cytokines, interleukin-6, tumor necrosis factor-alpha, and macrophage inflammatory protein-1beta in isolated airway macrophages and increased levels of total matrix metalloprotease-9 activity in induced sputum from the HMOE group. Our findings indicate that paper industry workers exposed to MOs develop subclinical airway inflammation.

In demonstrations of column distillation for the general public or in other demonstration settings, the audience often lacks the equipment or knowledge to access the distillation process. Distillation of solvents usually gives colorless solution. By adding bromophenol blue (BPB) to the distillation of water and ethanol, the authors have developed a setup sensitive to different ethanol concentrations, allowing direct visualization of the distillation process. The color in the distillation column changes from blue to yellow in the distillation column as ethanol concentration changes. Bromophenol blue indicator can also be used to quickly and semiquantitatively determine the ethanol concentration in binary ethanol–water mixtures in laboratory settings.

Numerical weather and climate use sophisticated mathematical models. These models are employed to simulate the atmospheric dynamics to perform a medium-range forecasting and climate prediction. Such an approach allows to estimate all meteorological variables for a future time period: wind fields, air temperature, pressure, moisture, and precipitation field. Precipitation is one of the most difficult fields for prediction. The latter statement is verified due to high variability in space and time. However, precipitation is a key issue in many activities of society. An alternative approach for climate prediction to the precipitation field is to employ the Artificial Neural Network (ANN). Such technique has a reduced computational cost in comparison with time integration of the partial differential equations. One challenge to employ an ANN is to determine the topology or configuration of a neural network. Here, a supervised ANN is designed to perform the precipitation prediction looking at two different periods: monthly and seasonal precipitation. The method is applied to the Southern region of Brazil. The definition of the neural network topology is addressed as an optimization problem. The best configuration is computed by minimizing a cost function. The optimization problem is solved by a new meta-heuristic: Multi-Particle Collision Algorithm (MPCA). In addition, a technique based on rough set theory is used to reduce the data space dimension. The predicted precipitation is evaluated by comparison with measured data. The prediction is also evaluated using full and reduced input data for a neural predictive model.

Chemical reaction engineering is one of the core courses for chemical engineering students. Laboratory exercise is an essential part of this course. The goal of this laboratory exercise is to demonstrate the possibility of using an in-situ spectroscopic method (UV-VIS spectroscopy) to investigate reaction kinetics. A solution of naphthol blue black (NBB) is oxidized by H 2 O 2 through a Fenton oxidation process. In this exercise, the concentration of NBB was monitored by the UV-VIS spectroscopy, while the concentrations of H 2 O 2 , FeSO 4 and different pH levels may be adjusted to enable students to obtain a wide range of reaction kinetic data. The reaction rate constant, k app , can be estimated with a pseudo-first-order kinetic model. In addition, the reaction temperature was adjusted to investigate the decomposition activation energy (E a), which exhibited a value of 56.0±7 kJ mol-1 .