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From August to December of 2016, a diagnostic and strategic planning study was carried out on the supply chain of the company Agropecuaria GABO S.A. de C.V. The final product of the study was the development of the strategic plan and a project portfolio to meet the demands of the three links in the supply chain of the Roma tomato exported annually to the United States of America. In this project, the strategic objective of ensuring the proper handling of the product was selected and one of the goals associated with this was the employment of quantitative methods to support decision making. Considering the antecedents, the objective of this case study was to develop a model to analyze the behavioral dynamics in the distribution chain, from the logistics of storage and shipment of Roma tomato in 81-case pallets (11.5 kg per case), to the two pre-cooling rooms and eventual loading onto transports, seeking to reduce the bottleneck and the associated costs by means of a dynamic interface. The methodology used was that of system dynamics, considering four phases that were adapted to the purpose of the study: 1) the conceptualization phase; 2) the formulation phase; 3) the evaluation phase; and 4) the communication phase. The main practical conclusions lead to the possibility of reducing both the bottlenecks in the cooling rooms and the costs by simulating scenarios and modifying certain policies. Furthermore, the creation of the dynamic interface between the model and the stakeholders was achieved by generating interaction with buttons and simple instructions that allow making modifications and observing diverse behaviors.

Several studies have indicated the involvement of macrophages and dendritic cells in active inflammatory bowel disease (IBD). Manipulation of these cells is considered a very important therapeutic strategy for patients with IBD. We evaluated the effect of a new drug delivery system targeting microfold cells and macrophages with poly(DL-lactic acid) microspheres containing dexamethasone (Dx). Colitis was induced in BALB/c mice by 5% dextran sodium sulfate. Dx microspheres (n = 10) and only Dx (n = 10) were orally administered to dextran sodium sulfate-treated mice. Thereafter, serum levels and tissue distributions of Dx were investigated. To estimate the efficacy of this drug delivery system, we measured the histological score, myeloperoxidase activity and nitric oxide production, and gene expressions of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma in the colonic tissue. Serum Dx levels were not increased after oral administration of Dx microspheres. The tissue distribution of microspheres containing (125)I-labeled Dx in inflamed colon was significantly higher than in other organs. The histological score, myeloperoxidase activity, and nitric oxide production of the group treated with Dx microspheres were significantly lower than of those treated with Dx alone. Gene expressions of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma were down-regulated in mice treated with Dx microspheres. Microspheres containing glucocorticoids such as Dx, which target microfold cells and macrophages, can facilitate mucosal repair in experimental colitis and could be an ideal agent for treatment of human IBD.

Ulcerative colitis (UC) is a disease of the colon and rectum characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events. Prostaglandins are synthesized by cyclooxygenase (COX)-1 and -2 and exhibit both pro- and anti-inflammatory activity. To evaluate COX-1 and COX-2 immunoexpression in 42 cases of UC and to correlate it with clinicopathological parameters, COX-1 and COX-2 expression was investigated by the immunohistochemistry method. Only patients with all pertinent clinical and evolutive data as well as with adequate biopsy material were included in the study. Fifteen samples of colorectal adenocarcinoma and 14 of large bowel with no histological changes were used for positive and negative controls, respectively. UC patients showed COX-1 immunoreactivity in epithelial cells in 29% of the cases and in inflammatory cells in 43%. COX-2 positivity in epithelial and inflammatory cells was found in 69% of the samples. The comparison between UC and the control groups revealed that the UC group had significantly more positive cases for COX-1 and COX-2 in inflammatory cells. Immunohistochemistry allowed the identification of COX-1 and COX-2 expression in epithelial and inflammatory cells in UC biopsies. No significant difference between COX-1 and COX-2 immunoreactivity in epithelial and inflammatory cells was observed regarding the clinicopathological parameters. COX-2 presented low expression in normal colon and high expression in colorectal adenocarcinoma. COX-2 might play a role in the pathophysiologic processes of inflammatory bowel disease and the development of neoplasia. Treatment with selective COX-2 inhibitors might be an additional option for therapy.