Foodborne Parasitic Diseases in the Neotropics - A Review.

Within the Universal Declaration of Human Rights, it is stated that everyone has the right to an adequate standard of living, which ensures, as well as their family, health and well-being, and food, thereby ensuring adequate nutrition. One of the major threats to overcome this is to ensure food security, which becomes particularly challenging in developing countries due to the high incidence of parasitic diseases. The World Health Organization (WHO), considers it one of the main causes of morbidity, closely linked to poverty and related to inadequate personal hygiene, consumption of raw food, lack of sanitary services, limited access to drinking water and fecal contamination in the environment. It is estimated that more than a fifth of the world's population is infected by one or several intestinal parasites, and that in many countries of Central and South America the average percentage of infected people is 45%, being Taenia solium, Echinococcus granulosus, Toxoplasma gondii, Cryptosporidium spp, Entamoeba histolytica, Trichinella spiralis, Ascaris spp, Trypanosoma cruzi and Fasciola hepatica some of the most important ones in the neotropics. One of the main reasons why these diseases are diffi cult to control is t he ignorance of their lifecycles, as well as symptoms and current epidemiology of the disease, which contributes to a late or erroneous diagnosis. The present work aims to discuss and make public the current knowledge as well as the general characteristics of these diseases to the general audience.

Resiniferatoxin lowers TNF-α, NO and PGE2 in the intestinal phase and the parasite burden in the muscular phase of Trichinella spiralis infection.

During the course of infection with Trichinella spiralis, an inflammatory response is triggered at the intestinal level in the host, playing a crucial role in the expulsion and elimination of the parasite. However, several studies have demonstrated that this inflammatory response is harmful to the host; hence, the importance of studying molecules with therapeutic potential like resiniferatoxin, which is known to have an anti-inflammatory effect both in vitro and in vivo. In this article, we evaluated the anti-inflammatory activity of resiniferatoxin during the intestinal phase of T. spiralis infection by quantitatively determining the levels of TNF-α, NO and PGE2 as well as the percentage of eosinophils in the blood and intestinal pathology. In addition, parasite burden was determined during the muscle infection. Our results show that resiniferatoxin lowered the serum levels of TNF-α, NO and PGE2 , as well as the percentage of eosinophils in the blood and intestinal pathology during the intestinal infection. Moreover, resiniferatoxin also lowered the parasite burden in muscle, resulting in a reduction of the humoral response (IgG) associated to treatment with resiniferatoxin. These findings suggest a potential therapeutic use of the anti-inflammatory effect of resiniferatoxin, which also contributes to host defence against the challenge of T. spiralis infection.

Resiniferatoxin modulates the Th1 immune response and protects the host during intestinal nematode infection.

In the early stage of the intestinal phase of Trichinella spiralis infection, the host triggers a Th1-type immune response with the aim of eliminating the parasite. However, this response damages the host which favours the survival of the parasite. In the search for novel pharmacological strategies that inhibit the Th1 immune response and assist the host against T. spiralis infection, a recent study showed that resiniferatoxin had anti-inflammatory activity contributed to the host in T. spiralis infection. In this study, we evaluated whether RTX modulates the host immune response through the inhibition of Th1 cytokines in the intestinal phase. In addition, it was determined whether the treatment with RTX affects the infectivity of T. spiralis-L1 and the development of the T. spiralis life cycle. Our results show that RTX decreased serum levels of IL-12, INF-γ, IL-1ß, TNF-α and parasite burden on muscle tissue. It was observed that T. spiralis-L1 treated with RTX decreased their infectivity affecting the development of the T. spiralis life cycle in mouse. These results demonstrate that RTX is able to inhibit the production of Th1 cytokines, contributing to the defence against T. spiralis, which places it as a potential drug modulator of the immune response.

Evaluation of the prognostic value of the metabolic volumetric parameters calculated with 18F-FDG PET/CT and its value added to the molecular characteristics in patients with diffuse large B-cell lymphoma.

INTRODUCTION AND OBJECTIVES: Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are prognostic predictors in patients with diffuse large B-cell lymphoma (DLBCL). The objective of this study is to evaluate the prognostic impact of the baseline volumetric parameters calculated with positron emission tomography/computed tomography with 18F-fluorodeoxyglucose (18F-FDG PET/CT) and its added value to the molecular characteristics in patients with DLBCL not otherwise specified (NOS). METHODOLOGY: This is a retrospective observational study, which included 35 patients who underwent a baseline 18F-FDG PET/CT prior to treatment. A univariate analysis of the volumetric parameters (MTV and TLG), immunohistochemical study and chromosomal translocations were performed. The method for calculating the volumetric parameters was the SUV 2.5 threshold. The comparison between the predictive models was selected based on the information criterion value of Akaike (AIC), bayesian (BIC) and Harrell's C, after performing a Cox proportional hazards regression model. In addition, a univariate analysis of the volumetric parameters was performed according to the data of the immunohistochemical study using the Wilcoxon-Mann-Whitney test. RESULTS: A univariate analysis revealed that VMT and TLG are predictors of progression-free survival (PFS) and overall survival (OS), with a high discrimination capacity. Adding VMT and TLG to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS in patients diagnosed with DLBCL-NOS. Likewise, it was evidenced that the values of the volumetric parameters were lower in patients who presented a germinal center B cell phenotype (GCB) compared to patients with an activated B cell phenotype (ABC) who presented higher values. CONCLUSION: MTV and TLG added to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS in patients diagnosed with DLBCL-NOS.

Kinetics of aggregation in non-Brownian magnetic particle dispersions in the presence of perturbations.

An experimental and theoretical study on the kinetics of the aggregation process of magnetic particles dispersed in mineral oils is presented. A static magnetic field and an oscillating magnetic perturbation are applied on the dispersion. In the low-particle concentrations, the effects on the aggregation of the frequency, the concentration of particles and the viscosity of the liquid are analyzed. It was found that the behavior of the cluster length as a function of the main control parameters can be accurately characterized by scaling relations. The physical characteristics of the aggregates are discussed in relation to measurements of viscosity as a function of time.

Bollgard cotton and resistance of tobacco budworm (Lepidoptera: Noctuidae) to conventional insecticides in southern Tamaulipas, Mexico.

Insecticide susceptibility in tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), was determined for 8 yr (1991-2001) with larvae sampled from cotton in southern Tamaulipas, Mexico. Before 1996, when Bollgard cotton expressing the Cry1A(c) delta-endotoxin was introduced into the region, two important patterns were documented. The first was economically significant increases in resistance to certain insecticide groups. The second was occurrence of virtually complete control failures in the field during 1994 and 1995. The largest resistance changes were recorded for the type II pyrethroids cypermethrin and deltamethrin. These products are the most widely used products in the region. Resistance ratios for these products increased up to > 100-fold from 1991 to 1995. After 1996, the resistance levels declined. These findings did not occur with other products of scant use (e.g., permethrin, profenofos, and endosulfan) or low tobacco budworm efficacy coupled to a high use pattern (e.g., methyl parathion). This clear trend toward reversal of resistance to type II pyrethroids can be understood, in part, with respect to two factors: 1) the high adoption rate of transgenic cotton in the region, from 31.2% in the beginning (1996) to approximately 90% in 1998; this has considerably curbed the use of synthetic insecticides, with the attending loss of selection pressure on this pest; and 2) the potential immigration to the region of susceptible tobacco budworms from cultivated and wild suitable hosts as well as from transgenic cotton might have influenced the pest population as a whole. The influence of transgenic cotton on southern Tamaulipas can be more clearly seen by the drastic reduction of insecticide use to control this important pest. Now tobacco budworms in this region are susceptible to type II pyrethroids. Two effective and fundamentally different pest management tools are now available to cotton growers in southern Tamaulipas: transgenic cotton, coupled with careful use of pyrethroids, offers the possibility of sustainable and profitable cotton production.

Lipoprotein alterations in patients with HIV infection: relation with cellular and humoral immune markers.

In order to determine lipid abnormalities in serum in HIV-infected patients and their relation with humoral and cellular immunological changes. Ninety HIV-infected patients without acute inflammatory or malignant disease have been studied. Thirty healthy HIV-negative subjects constituted the control group. As compared with controls, patients with CD4 + lymphocytes > 400 x 10(6)/l had higher triglycerides and lower high density lipoprotein (HDL)-cholesterol and apolipoprotein (apo)-A1. Lipoprotein comparison by groups of patients according to CD4 + cell counts showed a decrease of HDL-cholesterol in patients with CD4 + cells < or = 200 x 10(6)/l. When CD4 + lymphocyte counts were < 50 x 10(6)/l, total and very low density lipoprotein (VLDL)-triglycerides and VLDL-cholesterol were increased and HDL and low density lipoprotein (LDL)-cholesterol and apo-A1 were decreased. Interferon (IFN)-alpha, beta2-microglobulin and tumor necrosis factor (TNF)-alpha were correlated positively with total and VLDL-triglycerides and negatively with HDL-cholesterol. In conclusion, lipoprotein changes in patients with HIV-infection are related with humoral and cellular immune markers. A decrease of HDL-cholesterol and apo-A1 and an increase of triglyceride levels could be considered as markers of disease progression.

Fractal patterns, cluster dynamics, and elastic properties of magnetorheological suspensions.

We study pattern formation and the aggregation processes in magnetorheological suspensions in the presence of a static magnetic field, and some of their associated physical properties. In particular, we analyze the elastic modes as a function of the intensity of the applied field and for several particle concentrations. We observe that the clusters formed in these systems have multifractal characteristics, which are the result of three well defined stages of the aggregation process. In these stages three generations of clusters are produced sequentially. The structure of the suspension can be well characterized by its mass fractal dimensions and the mass radial distribution. The size distribution of the second-generation clusters written in terms of their mass fractal dimension allows us to calculate the sound speed of the longitudinal modes in the large wavelength regime. This multifractal analysis applied to several kinds of aggregates reveals that the occurrence of at least three stages of aggregation is a common feature to several physical aggregation processes.

[The health of a city: Seville in the turn-of-the-century crisis]. / La salud de una ciudad: Sevilla ante la crisis finisecular.

In this article we analyze three projects for urban reform in Seville in which health constitutes a primary element. These three projects are framed within the dialectic process of degeneration-regeneration which characterized the last decade of the nineteenth century in Spain, and which was a basic aspect of the collective way of thinking. Healthiness became an argument used by groups and individuals with the objective of defending their interests, in this case, those related to the use of urban space.