Educational innovation in large groups. Design of an experimental study implemented at the Polytechnic University of Madrid

The present paper shows de design of an experimental study conducted with large groups using educational innovation methodologies at the Polytechnic University of Madrid. Concretely, we have chosen the course titled "History and Politics of Sports" that belongs to the Physical Activity and Sport Science Degree. The selection of this course is because the syllabus is basically theoretical and there are four large groups of freshmen students who do not have previous experiences in a teaching-learning process based on educational innovation. It is hope that the results of this research can be extrapolated to other courses with similar characteristics.

Association of oxamniquine praziquantel and clonazepam in experimental Schistosomiasis mansoni

The antischistosomal activity of clonazepam, when administered alone or in association with oxamniquine and praziquantel, was experimentally evaluated in mice infected with Schistosoma mansoni. The animals were treated 45 days post-infection with a single dose, by oral route, according to three treatment schedules: clonazepam 25 mg/kg and sacrificed 15 min, 1h or 4 h after treatment; clonazepam 1.0, 2.5 or 10.0 mg/kg and sacrificed 15 days post-treatment or with the dose of 10 mg/kg in association with oxamniquine 50 mg/kg or praziquantel 200 mg/kg, single dose, orally, every schedule with a control group. The efficacy of the drugs in vivo was assessed by means of worm counts and their distribution in mesentery and liver, mortality and oogram changes. In the chemotherapeutic schedules used, clonazepam did not present antischistosomal activity and the result of the association of this drug with oxamniquine or praziquantel was not significantly different from the one obtained when these two last drugs were administered alone. In the in vitro experiments, the worms exposed to 0.6 mg/mL clonazepam remained motionless throughout the 8-day-period of observation, without egg-laying, whereas the worms of the control group showed normal movements, egg-laying and hatching of miracidia on the last day of observation. The results obtained in the present study confirm the action of clonazepam on S. mansoni adult worm, in vitro, causing total paralysis of males and females. However, no additive or synergistic effects were observed when clonazepam were used in association with oxamniquine or praziquantel.

Linezolid alone or combined with rifampin against methicillin-resistant Staphylococcus aureus in experimental foreign-body infection.

We investigated the activity of linezolid, alone and in combination with rifampin (rifampicin), against a methicillin-resistant Staphylococcus aureus (MRSA) strain in vitro and in a guinea pig model of foreign-body infection. The MIC, minimal bactericidal concentration (MBC) in logarithmic phase, and MBC in stationary growth phase were 2.5, >20, and >20 microg/ml, respectively, for linezolid; 0.01, 0.08, and 2.5 microg/ml, respectively, for rifampin; and 0.16, 0.63, >20 microg/ml, respectively, for levofloxacin. In time-kill studies, bacterial regrowth and the development of rifampin resistance were observed after 24 h with rifampin alone at 1x or 4x the MIC and were prevented by the addition of linezolid. After the administration of single intraperitoneal doses of 25, 50, and 75 mg/kg of body weight, linezolid peak concentrations of 6.8, 12.7, and 18.1 microg/ml, respectively, were achieved in sterile cage fluid at approximately 3 h. The linezolid concentration remained above the MIC of the test organism for 12 h with all doses. Antimicrobial treatments of animals with cage implant infections were given twice daily for 4 days. Linezolid alone at 25, 50, and 75 mg/kg reduced the planktonic bacteria in cage fluid during treatment by 1.2 to 1.7 log(10) CFU/ml; only linezolid at 75 mg/kg prevented bacterial regrowth 5 days after the end of treatment. Linezolid used in combination with rifampin (12.5 mg/kg) was more effective than linezolid used as monotherapy, reducing the planktonic bacteria by >or=3 log(10) CFU (P < 0.05). Efficacy in the eradication of cage-associated infection was achieved only when linezolid was combined with rifampin, with cure rates being between 50% and 60%, whereas the levofloxacin-rifampin combination demonstrated the highest cure rate (91%) against the strain tested. The linezolid-rifampin combination is a treatment option for implant-associated infections caused by quinolone-resistant MRSA.

The immunomodulator PSK induces in vitro cytotoxic activity in tumour cell linesvia arrest of cell cycle and induction of apoptosis

BACKGROUND Protein-bound polysaccharide (PSK) is derived from the CM-101 strain of the fungus Coriolus versicolor and has shown anticancer activity in vitro and in in vivo experimental models and human cancers. Several randomized clinical trials have demonstrated that PSK has great potential in adjuvant cancer therapy, with positive results in the adjuvant treatment of gastric, esophageal, colorectal, breast and lung cancers. These studies have suggested the efficacy of PSK as an immunomodulator of biological responses. The precise molecular mechanisms responsible for its biological activity have yet to be fully elucidated. METHODS The in vitro cytotoxic anti-tumour activity of PSK has been evaluated in various tumour cell lines derived from leukaemias, melanomas, fibrosarcomas and cervix, lung, pancreas and gastric cancers. Tumour cell proliferation in vitro was measured by BrdU incorporation and viable cell count. Effect of PSK on human peripheral blood lymphocyte (PBL) proliferation in vitro was also analyzed. Studies of cell cycle and apoptosis were performed in PSK-treated cells. RESULTS PSK showed in vitro inhibition of tumour cell proliferation as measured by BrdU incorporation and viable cell count. The inhibition ranged from 22 to 84%. Inhibition mechanisms were identified as cell cycle arrest, with cell accumulation in G0/G1 phase and increase in apoptosis and caspase-3 expression. These results indicate that PSK has a direct cytotoxic activity in vitro, inhibiting tumour cell proliferation. In contrast, PSK shows a synergistic effect with IL-2 that increases PBL proliferation. CONCLUSION These results indicate that PSK has cytotoxic activity in vitro on tumour cell lines. This new cytotoxic activity of PSK on tumour cells is independent of its previously described immunomodulatory activity on NK cells.

Experimental chemotherapy for Chagas disease: 15 years of research contributions from in vivo and in vitro studies

Chagas disease, which is caused by the intracellular parasite Trypanosoma cruzi, is a neglected illness with 12-14 million reported cases in endemic geographic regions of Latin America. While the disease still represents an important public health problem in these affected areas, the available therapy, which was introduced more than four decades ago, is far from ideal due to its substantial toxicity, its limited effects on different parasite stocks, and its poor activity during the chronic phase of the disease. For the past 15 years, our group, in collaboration with research groups focused on medicinal chemistry, has been working on experimental chemotherapies for Chagas disease, investigating the biological activity, toxicity, selectivity and cellular targets of different classes of compounds on T. cruzi. In this report, we present an overview of these in vitro and in vivo studies, focusing on the most promising classes of compounds with the aim of contributing to the current knowledge of the treatment of Chagas disease and aiding in the development of a new arsenal of candidates with anti-T. cruzi efficacy.

Aliskiren penetrates adipose and skeletal muscle tissue, and reduces Renin-Angiotensin System activity in obese hypertensive patients

Introduction: Tissue Renin-Angiotensin System activity is increased in obesity and may contribute to obesity-related hypertension and metabolic abnormalities. This open-label pilot study investigated the local effects of Aliskiren in adipose tissue and skeletal muscle.Methods: After a 1-2 week washout, 10 patients with hypertension and abdominal obesity received placebo for 2 weeks, then Aliskiren 300 mg once daily for 4 weeks, followed by a 4-week washout period and then another 4 weeks treatment period with Amlodipine 5 mg once daily. Drug concentrations and Renin-Angiotensin Systembiomarkers were measured in interstitial fluid employing the microdialysis zero-flow method, and in biopsies from abdominal subcutaneous adipose and skeletal muscle.Results: After 4 weeks treatment, microdialysate concentrations (mean±SD) of Aliskiren were 2.4±2.1 ng/ml in adipose tissue, and 7.1±4.2 ng/ml in skeletal muscle. These concentrations were similar to the mean plasma concentration of 8.4±4.4 ng/ml. Tissue concentrations (ng/g) of Aliskiren were 29.0±16.7 ng/g in adipose tissue, and 107.3±68.6 ng/g in skeletal muscle after 4 weeks treatment. Angiotensin II concentrations in microdialysates were below the lower limit of quantification in most patients, but pooled data from two patients suggested that Angiotensin II was reduced by Aliskiren and unchanged by Amlodipine. Aliskiren 300 mg significantly reduced mean plasma Renin activity by 68% and Angiotensin II by 61% (p<0.05 vs. baseline). Amlodipine 5 mg increased plasma Renin activity by 48% (p<0.05 vs. baseline), and non-significantly increased Angiotensin II by 60%. Both treatments increased plasma Renin concentration.Conclusion: Aliskiren 300 mg once daily penetrates adipose and skeletal muscle tissue at concentrations sufficient to reduce tissue Renin-Angiotensin System activity in obese patients with hypertension.

Acute experimental Trypanosoma cruzi infection: establishing a murine model that utilises non-invasive measurements of disease parameters

Trypanosoma cruzi infection has a large public health impact in Latin American countries. Although the transmission rates via blood transfusions and insect vectors have declined sharply in the past 20 years due to policies of the Southern Cone countries, a large number of people are still at risk for infection. Currently, no accepted experimental model or descriptions of the clinical signs that occur during the course of acute murine infection are available. The aim of this work was to use non-invasive methods to evaluate the clinical signs of Balb/c mice infected with the Y strain of T. cruzi. The infected mice displayed evident clinical changes beginning in the third week of infection. The mice were evaluated based on physical characteristics, spontaneous activity, exploratory behaviour and physiological alterations. We hope that the results presented in this report provide parameters that complement the effective monitoring of trypanocidal treatment and other interventions used to treat experimental Chagas disease.

Gut Microbiota Composition in Male Rat Models under Different Nutritional Status and Physical Activity and Its Association with Serum Leptin and Ghrelin Levels.

BACKGROUND Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. OBJECTIVE To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. METHODS IN A CASE CONTROL STUDY, FORTY MALE RATS WERE RANDOMLY ASSIGNED TO ONE OF THESE FOUR EXPERIMENTAL GROUPS: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. RESULTS In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides-E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides-Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. CONCLUSIONS Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations between gut microbiota and appetite-regulating hormones that may be important in terms of satiety and host metabolism.

Levofloxacin versus ciprofloxacin, flucloxacillin, or vancomycin for treatment of experimental endocarditis due to methicillin-susceptible or -resistant Staphylococcus aureus.

Levofloxacin is the L isomer of ofloxacin, a racemic mixture in which the L stereochemical form carries the antimicrobial activity. Levofloxacin is more active than former quinolones against gram-positive bacteria, making it potentially useful against such pathogens. In this study, levofloxacin was compared to ciprofloxacin, flucloxacillin, and vancomycin for the treatment of experimental endocarditis due to two methicillin-susceptible Staphylococcus aureus (MSSA) and two methicillin-resistant S. aureus (MRSA) isolates. The four test organisms were susceptible to ciprofloxacin, the levofloxacin MICs for the organisms were low (0.12 to 0.25 mg/liter), and the organisms were killed in vitro by drug concentrations simulating both the peak and trough levels achieved in human serum (5 and 0.5 mg/liter, respectively) during levofloxacin therapy. Rats with aortic endocarditis were treated for 3 days. Antibiotics were injected with a programmable pump to simulate the kinetics of either levofloxacin (350 mg orally once a day), ciprofloxacin (750 mg orally twice a day), flucloxacillin (2 g intravenously four times a day), or vancomycin (1 g intravenously twice a day). Levofloxacin tended to be superior to ciprofloxacin in therapeutic experiments (P = 0.08). More importantly, levofloxacin did not select for resistance in the animals, in contrast to ciprofloxacin. The lower propensity of levofloxacin than ciprofloxacin to select for quinolone resistance was also clearly demonstrated in vitro. Finally, the effectiveness of this simulation of oral levofloxacin therapy was at least equivalent to that of standard treatment for MSSA or MRSA endocarditis with either flucloxacillin or vancomycin. This is noteworthy, because oral antibiotics are not expected to succeed in the treatment of severe staphylococcal infections. These good results obtained with animals suggest that levofloxacin might deserve consideration for further study in the treatment of infections due to ciprofloxacin-susceptible staphylococci in humans.

The forgotten face of regular physical exercise: a 'natural' anti-atherogenic activity.

Humans are not programmed to be inactive. The combination of both accelerated sedentary lifestyle and constant food availability disturbs ancient metabolic processes leading to excessive storage of energy in tissue, dyslipidaemia and insulin resistance. As a consequence, the prevalence of Type 2 diabetes, obesity and the metabolic syndrome has increased significantly over the last 30 years. A low level of physical activity and decreased daily energy expenditure contribute to the increased risk of cardiovascular morbidity and mortality following atherosclerotic vascular damage. Physical inactivity leads to the accumulation of visceral fat and consequently the activation of the oxidative stress/inflammation cascade, which promotes the development of atherosclerosis. Considering physical activity as a 'natural' programmed state, it is assumed that it possesses atheroprotective properties. Exercise prevents plaque development and induces the regression of coronary stenosis. Furthermore, experimental studies have revealed that exercise prevents the conversion of plaques into a vulnerable phenotype, thus preventing the appearance of fatal lesions. Exercise promotes atheroprotection possibly by reducing or preventing oxidative stress and inflammation through at least two distinct pathways. Exercise, through laminar shear stress activation, down-regulates endothelial AT1R (angiotensin II type 1 receptor) expression, leading to decreases in NADPH oxidase activity and superoxide anion production, which in turn decreases ROS (reactive oxygen species) generation, and preserves endothelial NO bioavailability and its protective anti-atherogenic effects. Contracting skeletal muscle now emerges as a new organ that releases anti-inflammatory cytokines, such as IL-6 (interleukin-6). IL-6 inhibits TNF-α (tumour necrosis factor-α) production in adipose tissue and macrophages. The down-regulation of TNF-α induced by skeletal-muscle-derived IL-6 may also participate in mediating the atheroprotective effect of physical activity.

Severity of chronic experimental Chagas' heart disease parallels tumour necrosis factor and nitric oxide levels in the serum: models of mild and severe disease

Heart tissue inflammation, progressive fibrosis and electrocardiographic alterations occur in approximately 30% of patients infected by Trypanosoma cruzi, 10-30 years after infection. Further, plasma levels of tumour necrosis factor (TNF) and nitric oxide (NO) are associated with the degree of heart dysfunction in chronic chagasic cardiomyopathy (CCC). Thus, our aim was to establish experimental models that mimic a range of parasitological, pathological and cardiac alterations described in patients with chronic Chagas’ heart disease and evaluate whether heart disease severity was associated with increased TNF and NO levels in the serum. Our results show that C3H/He mice chronically infected with the Colombian T. cruzi strain have more severe cardiac parasitism and inflammation than C57BL/6 mice. In addition, connexin 43 disorganisation and fibronectin deposition in the heart tissue, increased levels of creatine kinase cardiac MB isoenzyme activity in the serum and more severe electrical abnormalities were observed in T. cruzi-infected C3H/He mice compared to C57BL/6 mice. Therefore, T. cruzi-infected C3H/He and C57BL/6 mice represent severe and mild models of CCC, respectively. Moreover, the CCC severity paralleled the TNF and NO levels in the serum. Therefore, these models are appropriate for studying the pathophysiology and biomarkers of CCC progression, as well as for testing therapeutic agents for patients with Chagas’ heart disease.

Inoculum effect on the efficacies of amoxicillin-clavulanate, piperacillin-tazobactam, and imipenem against extended-spectrum β-lactamase (ESBL)-producing and non-ESBL-producing Escherichia coli in an experimental murine sepsis model.

Escherichia coli is commonly involved in infections with a heavy bacterial burden. Piperacillin-tazobactam and carbapenems are among the recommended empirical treatments for health care-associated complicated intra-abdominal infections. In contrast to amoxicillin-clavulanate, both have reduced in vitro activity in the presence of high concentrations of extended-spectrum β-lactamase (ESBL)-producing and non-ESBL-producing E. coli bacteria. Our goal was to compare the efficacy of these antimicrobials against different concentrations of two clinical E. coli strains, one an ESBL-producer and the other a non-ESBL-producer, in a murine sepsis model. An experimental sepsis model {~5.5 log10 CFU/g [low inoculum concentration (LI)] or ~7.5 log(10) CFU/g [high inoculum concentration (HI)]} using E. coli strains ATCC 25922 (non-ESBL producer) and Ec1062 (CTX-M-14 producer), which are susceptible to the three antimicrobials, was used. Amoxicillin-clavulanate (50/12.5 mg/kg given intramuscularly [i.m.]), piperacillin-tazobactam (25/3.125 mg/kg given intraperitoneally [i.p.]), and imipenem (30 mg/kg i.m.) were used. Piperacillin-tazobactam and imipenem reduced spleen ATCC 25922 strain concentrations (-2.53 and -2.14 log10 CFU/g [P < 0.05, respectively]) in the HI versus LI groups, while amoxicillin-clavulanate maintained its efficacy (-1.01 log10 CFU/g [no statistically significant difference]). Regarding the Ec1062 strain, the antimicrobials showed lower efficacy in the HI than in the LI groups: -0.73, -1.89, and -1.62 log10 CFU/g (P < 0.05, for piperacillin-tazobactam, imipenem, and amoxicillin-clavulanate, respectively, although imipenem and amoxicillin-clavulanate were more efficacious than piperacillin-tazobactam). An adapted imipenem treatment (based on the time for which the serum drug concentration remained above the MIC obtained with a HI of the ATCC 25922 strain) improved its efficacy to -1.67 log10 CFU/g (P < 0.05). These results suggest that amoxicillin-clavulanate could be an alternative to imipenem treatment of infections caused by ESBL- and non-ESBL-producing E. coli strains in patients with therapeutic failure with piperacillin-tazobactam.

Assessment of Physical Activity and Energy Expenditure by GPS Combined With Accelerometry in Real-Life Conditions.

Background: Physical activity (PA) and related energy expenditure (EE) is often assessed by means of a single technique. Because of inherent limitations, single techniques may not allow for an accurate assessment both PA and related EE. The aim of this study was to develop a model to accurately assess common PA types and durations and thus EE in free-living conditions, combining data from global positioning system (GPS) and 2 accelerometers. Methods: Forty-one volunteers participated in the study. First, a model was developed and adjusted to measured EE with a first group of subjects (Protocol I, n = 12) who performed 6 structured and supervised PA. Then, the model was validated over 2 experimental phases with 2 groups (n = 12 and n = 17) performing scheduled (Protocol I) and spontaneous common activities in real-life condition (Protocol II). Predicted EE was compared with actual EE as measured by portable indirect calorimetry. Results: In protocol I, performed PA types could be recognized with little error. The duration of each PA type could be predicted with an accuracy below 1 minute. Measured and predicted EE were strongly associated (r = .97, P < .001). Conclusion: Combining GPS and 2 accelerometers allows for an accurate assessment of PA and EE in free-living situations.

Enhanced heat shock protein 70 expression alters proteasomal degradation of IkappaB kinase in experimental acute respiratory distress syndrome.

OBJECTIVES: Acute respiratory distress syndrome is a common and highly lethal inflammatory lung syndrome. We previously have shown that an adenoviral vector expressing the heat shock protein (Hsp)70 (AdHSP) protects against experimental sepsis-induced acute respiratory distress syndrome in part by limiting neutrophil accumulation in the lung. Neutrophil accumulation and activation is modulated, in part, by the nuclear factor-kappaB (NF-kappaB) signal transduction pathway. NF-kappaB activation requires dissociation/degradation of a bound inhibitor, IkappaBalpha. IkappaBalpha degradation requires phosphorylation by IkappaB kinase, ubiquitination by the SCFbeta-TrCP (Skp1/Cullin1/Fbox beta-transducing repeat-containing protein) ubiquitin ligase, and degradation by the 26S proteasome. We tested the hypothesis that Hsp70 attenuates NF-kappaB activation at multiple points in the IkappaBalpha degradative pathway. DESIGN: Laboratory investigation. SETTING: University medical center research laboratory. SUBJECTS: Adolescent (200 g) Sprague-Dawley rats and murine lung epithelial-12 cells in culture. INTERVENTIONS: Lung injury was induced in rats via cecal ligation and double puncture. Thereafter, animals were treated with intratracheal injection of 1) phosphate buffer saline, 2) AdHSP, or 3) an adenovirus expressing green fluorescent protein. Murine lung epithelial-12 cells were stimulated with tumor necrosis factor-alpha and transfected. NF-kappaB was examined using molecular biological tools. MEASUREMENTS AND MAIN RESULTS: Intratracheal administration of AdHSP to rats with cecal ligation and double puncture limited nuclear translocation of NF-kappaB and attenuated phosphorylation of IkappaBalpha. AdHSP treatment reduced, but did not eliminate, phosphorylation of the beta-subunit of IkappaB kinase. In vitro kinase activity assays and gel filtration chromatography revealed that treatment of sepsis-induced lung injury with AdHSP induced fragmentation of the IkappaB kinase signalosome. This stabilized intermediary complexes containing IkappaB kinase components, IkappaBalpha, and NF-kappaB. Cellular studies indicate that although ubiquitination of IkappaBalpha was maintained, proteasomal degradation was impaired by an indirect mechanism. CONCLUSIONS: Treatment of sepsis-induced lung injury with AdHSP limits NF-kappaB activation. This results from stabilization of intermediary NF-kappaB/IkappaBalpha/IkappaB kinase complexes in a way that impairs proteasomal degradation of IkappaBalpha. This novel mechanism by which Hsp70 attenuates an intracellular process may be of therapeutic value.

The systemic administration of oleoylethanolamide exerts neuroprotection of the nigrostriatal system in experimental Parkinsonism.

Oleoylethanolamide (OEA) is an agonist of the peroxisome proliferator-activated receptor α (PPARα) and has been described to exhibit neuroprotective properties when administered locally in animal models of several neurological disorder models, including stroke and Parkinson's disease. However, there is little information regarding the effectiveness of systemic administration of OEA on Parkinson's disease. In the present study, OEA-mediated neuroprotection has been tested on in vivo and in vitro models of 6-hydroxydopamine (6-OH-DA)-induced degeneration. The in vivo model was based on the intrastriatal infusion of the neurotoxin 6-OH-DA, which generates Parkinsonian symptoms. Rats were treated 2 h before and after the 6-OH-DA treatment with systemic OEA (0.5, 1, and 5 mg/kg). The Parkinsonian symptoms were evaluated at 1 and 4 wk after the development of lesions. The functional status of the nigrostriatal system was studied through tyrosine-hydroxylase (TH) and hemeoxygenase-1 (HO-1, oxidation marker) immunostaining as well as by monitoring the synaptophysin content. In vitro cell cultures were also treated with OEA and 6-OH-DA. As expected, our results revealed 6-OH-DA induced neurotoxicity and behavioural deficits; however, these alterations were less severe in the animals treated with the highest dose of OEA (5 mg/kg). 6-OH-DA administration significantly reduced the striatal TH-immunoreactivity (ir) density, synaptophysin expression, and the number of nigral TH-ir neurons. Moreover, 6-OH-DA enhanced striatal HO-1 content, which was blocked by OEA (5 mg/kg). In vitro, 0.5 and 1 μM of OEA exerted significant neuroprotection on cultured nigral neurons. These effects were abolished after blocking PPARα with the selective antagonist GW6471. In conclusion, systemic OEA protects the nigrostriatal circuit from 6-OH-DA-induced neurotoxicity through a PPARα-dependent mechanism.