Understanding new molecular and cell biology findings based on progressive scientific practices and interconnected activities in undergraduate students.

Nowadays Molecular Cell Biology (MCB) must be taught as science is practiced. Even though there are several approaches based on scientific practices, a key aspect is to define the purpose of each of these teaching strategies and, most importantly, their implementation. Our goal was to train students to acquire, understand, and communicate new scientific knowledge in the field. The main feature of our new teaching methodology was progressive training in scientific practices associated with a back-and-forward interplay between activities and assessments. The methodology was implemented over 4 years, in students attending the MCB course of the undergraduate degree in Biological Sciences. In the first two modules, the students were prepared to comprehend MCB concepts and techniques and to experience activities based on scientific practices. In the third module, the students analyzed a primary paper in-depth. They were assessed by midterm exams based on a primary paper, written laboratory reports, and the oral presentation of a scientific paper. Our teaching proposal was evaluated through the students' academic performance and by their opinion on the teaching methodology. Most students were satisfied since they improved their acquisition of concepts, their interpretation and integration of scientific knowledge, and developed skills to communicate scientific knowledge in writing and orally. The novelty of transversal interconnections and progressive training in scientific practices provides students with skills in acquiring and understanding new scientific information, even beyond the MCB course.

Laparoscopic surgery versus open surgery for treatment of acute appendicitis

AIMS. Update of the most recent guidelines in the treatment of Acute Appendicitis prior to the analysis of our service experience in the treatment of these patients in the last years comparing the outcomes of open (OA) vs. laparoscopic appendectomy (LA). METHODS. Patients diagnosed with Acute Appendicitis who were admitted to our Surgery Department from January 2006, to January 2010, were divided in two groups: OA and LA according to the technique employed. A retrospective study was undertaken comparing the data obtained from medical records. RESULTS. A total of 339 patients were included in our study, 122 underwent Laparoscopic Appendectomy (mean age 32.95 years) and 177 had Open surgery (mean age 37.17 years). The post operative stay in days was 4.41 for LA and 3.72 for the OA group. The analysis of the complications showed that 10% of the patients on the OA group stayed more than 10 days hospitalized due to complications; in the LA group only 5.73% of patients had a prolonged stay. CONCLUSIÓNS: 1. According to recent studies when antibiotics were used as the sole treatment for acute appendicitis the rate of recurrence in the first year reaches 13.9%. 2. Evidence published about LA outcomes show fewer wound infection, more intra-abdominal abscess, longer operative time, less postoperative pain, shorter post operative stay, same time to return to work and grater administrative costs. 3. Our case series reports similar results to those published, with fewer postoperative complications including intra-abdominal abscesses. A larger sample is needed to extract definitive conclusions (AU)

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Analysis of tissue bioimpedance as a measurement of liver steatosis: experimental model in large animals.

BACKGROUND: Electrical bioimpedance (BI) has been used to indirectly measure steatosis. This method has not yet been established in the clinics thus experimental studies are needed in big animals. We assessed BI to measure liver steatosis in porcine animals. METHODS: Twelve large-white × Landrace pigs weighing 35 kg were allocated to a study (n = 9) and a control group (n = 3). A special diet was used to promote steatosis among the study group: methionine deficient and choline-restricted diet that contains supplements of cholesterol, collate and excess of saturated fat. Control group animals were fed a normal diet. A new tetrapolar electrode model was used for BI measurement, which were performed during open laparotomy by inserting a probe into one of the lobes. Measurements were done in the third and fourth segments of the pig liver, placing the probe either on the surface or inserted into the parenchyma of the liver. Open biopsies were obtained at the end of the measurements. Histological samples were processed and stained with hematoxylin-eosin to estimate macrosteatosis. Pearson correlation coefficient between BI and percentage steatosis were calculated at different frequencies. RESULTS: After 4 months of the special diet all the animals in the study group developed steatosis (90% to 20%), whereas none of the control group was affected. Pearson correlation coefficients between BI and percentage of steatosis were significant (0.877-0.878) with the best correlations obtained with a probe placed on the fourth segment of the liver surface and the best frequency to perform the measurements being 50 and 75 kHz. CONCLUSIONS: BI is an accurate, fast method for steatosis measurements, that is easier and cheaper than either open or needle biopsy.

Heavy metals and trace elements in atmospheric fall-out: their relationship with topsoil and wheat element composition.

The objectives of this study were to determine the average concentrations and deposition rates of 28 elements in atmospheric bulk deposition and to elucidate associations among topsoil, bulk deposition and wheat element composition. The fluxes of arsenic (As), copper (Cu), lead (Pb) and zinc (Zn) deposition in Córdoba were higher than in other agro-ecosystems, which reflects both natural (geochemistry and topsoil removal) and anthropogenic sources. High lanthanide, uranium (U) and thorium (Th) concentrations revealed the impact of an open cast uranium mine. The highest enrichment factors (EF) were those of Cu, Pb, Zn and nickel (Ni), with calcium (Ca) being the most prominent in the surroundings of a cement plant. Industries and the transport of airborne urban pollutants were the main anthropogenic sources for Ca, Cu, Ni, Pb, Zn, cadmium (Cd), iron (Fe), manganese (Mn) and antimony (Sb). The concentrations of metals in wheat grain were predicted using the topsoil and atmospheric fall-out composition with R(2)=0.90, with the latter being the best explanatory variable. The present study highlights the potential health hazards of wheat consumption (Environmental Protection Agency) by the assessment of heavy metals in bulk atmospheric deposition.

Heavy metal and trace element concentrations in wheat grains: assessment of potential non-carcinogenic health hazard through their consumption.

Heavy metal and trace element concentrations were examined in wheat grains and straw to elucidate associations between air pollution sources and soil variables. The mean wheat grain concentrations of Cr, Cu, Fe, Mn and Zn surpassed the tolerance limits stated in the international legislation for wheat grain and foodstuffs. When topsoil Ba, Co, Cr and Zn concentrations were higher than the legislation thresholds for agricultural and residential soils, wheat grain concentrations were also increased. In addition, Cr, Cu, Mn, Ni, Pb, and Zn revealed an immobilization effect of a cement plant and the atmospheric deposition input, with Cd in wheat grains being associated with a cement plant and industrial waste incinerator. The health risks arising from wheat grain consumption indicated that the inhabitants of Argentina are experiencing significant non-carcinogenic risks (Hazard Index = 3.311), especially when consuming wheat grains affected by metallurgical or chemical factories, as well as by air transportation from big cities.

Antioxidant response of three Tillandsia species transplanted to urban, agricultural, and industrial areas.

To evaluate the physiological response of Tillandsia capillaris Ruiz & Pav. f. capillaris, T. recurvata L., and T. tricholepis Baker to different air pollution sources, epiphyte samples were collected from a noncontaminated area in the province of Córdoba (Argentina) and transplanted to a control site as well as three areas categorized according to the presence of agricultural, urban, and industrial (metallurgical and metal-mechanical) emission sources. A foliar damage index (FDI) was calculated with the physiological parameters chlorophyll a, chlorophyll b, malondialdehyde (MDA), hydroperoxyconjugated dienes, sulfur (S) content, and dry weight-to-fresh weight ratio. In addition, electrical conductivity (E-cond), relative water content (RWC), dehydration kinetics (Kin-H(2)O), total phenols (T-phen), soluble proteins (S-prot), and activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase were determined. The parameters E-cond, FDI, SOD, RWC, and Kin-H(2)O can serve as suitable indicators of agricultural air pollution for T. tricholepis and T. capillaris, and CAT, Kin-H(2)O, and SOD can do the same for T. recurvata. In addition, MDA, T-phen, and S-prot proved to be appropriate indicators of urban pollution for T. recurvata. Moreover, FDI, E-cond, and SOD for T. recurvata and MDA for T. tricholepis, respectively, could be used to detect deleterious effects of industrial air pollution.

Heavy metal pollution in topsoils near a cement plant: the role of organic matter and distance to the source to predict total and hcl-extracted heavy metal concentrations.

Heavy metal and trace element concentrations were examined in topsoils to evaluate a cement plant and an industrial waste incinerator as pollution sources. As, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb and Zn were measured by Neutron Activation Analysis (NAA), and Co, Cu, Fe, Ni, Pb and Zn by a 0.5M-hydrochloric extraction technique using an Atomic Absorption Spectrophotometer (AAS). The Cr total concentration and HCl-extracted Co and Mn were possibly related to wind transportation from an industrial area in the north of Córdoba city (Argentina). Cu, Pb and Zn in partial HCl extraction were influenced by the cement plant and the industrial area in the north of Córdoba city. The mean total Ba concentration was above the residential and agricultural land use limits stated in national and international legislation and was related to the distance to the cement plant. The concentrations of HCl-extracted heavy metals could be predicted by the organic matter percentage and the distance to the cement plant (with R(2) values of 0.50-0.74). The Ca total concentration was seen to have little influence whereas the organic matter percentage strongly affected HCl-extracted heavy metals according to the correlation analysis and multiple regression models. According to soil quality guidelines for environmental health, the human and wildlife populations in Yocsina might be experiencing toxic Ba and Cr effects.

Comparison of the air pollution biomonitoring ability of three Tillandsia species and the lichen Ramalina celastri in Argentina.

Bioaccumulation ability and response to air pollution sources were evaluated for Tillandsia capillaris Ruíz and Pav. f. capillaris, T. recurvata L., T. tricholepis Baker and the lichen Ramalina celastri (Spreng.) Krog. and Swinsc. Epiphyte samples collected from a non contaminated area in the province of Córdoba were transplanted to a control site and three areas categorised according to agricultural, urban and industrial (metallurgical and metal-mechanical) emission sources. Bioindicators were exposed for 3-, 6- and 9-month periods. A foliar damage index was established for Tillandsia and a pollution index for the lichen, and S, Fe, Mn and Zn concentrations were determined. An order of efficiency for the species and conditions studied is proposed taking into account heavy metal accumulation: T. recurvata >T. tricholepis >R. celastri >T. capillaris. All species studied showed Mn to be related to agricultural activity and Fe to industries and soil particles, and Zn was related to urban and industrial sources. As far as physiological response is concerned, T. tricholepis and T. capillaris were more sensitive to agricultural activities, whereas T. recurvata was sensitive to urban and industrial sources, and only partially to agricultural sources. No relationship was found for R. celastri.

Epidemiology of urticaria in Spain.

BACKGROUND: In spite of the frequency of chronic urticaria there are very few epidemiological studies of its prevalence and distribution. OBJECTIVE: We wanted to approach the real prevalence of chronic urticaria in a population-based study and to depict demographic distribution and personal perception of the disease. We also wanted to describe the frequency of acute urticaria episodes in the population studied. METHODS: We conducted a population-based study among adults in Spain. We questioned 5003 individuals after calculating a sample size for a maximum variability (conservative approach p=q=0.5). RESULTS: We found a 0.6% (95% CI: 0.4-0.8) prevalence of chronic urticaria. The prevalence is significantly higher in women than in men with a OR=3.82 (95%CI 1.56-9.37). Chronic urticaria is a self-limited disease, yet in 8.7% of cases chronic urticaria lasts from one to 5 years and in 11.3%, for more than 5 years. The average age of onset is 40 years. CONCLUSIONS: We offer large epidemiology study data on the prevalence of chronic urticaria. The prevalence of chronic urticaria has not yet been defined in an adult population-based study. With this work we offer such data to describe the prevalence and features of this disease.

Prevalencia de alergia en la población adulta española / Allergy prevalence in adult spanish population

Introduccián: En lo últimos decenios se está registrando un aumento de las enfermedades alérgicas en todo el mundo. Sin embargo hay pocos estudios de prevalencia de alergia en la población general española. Objetivos: Establecer la prevalencia de enfermedades alérgicas en una muestra de población general adulta del estado español. Así como establecer las causas y las manifestaciones de esta alergia. Material y métodos: Se realizó un estudio observacional de tipo tranversal. El tamaño de la muestra. suponiendo un nivel máximo de indeterminación prevalencia = 50%) y aceptando un error del 1.4% y un nivel de confianza del 95%. Fue de 5.003 sujeto . La muestra e seleccionó de forma aleatoria y automática del listín de teléfono, aplicando el control de cuotas de zona. el número de habitantes, el sexo y la edad. La recogida 1:1e datos se efectuó mediante encuesta telefónica siguiendo la técnica CATI (Computer-assisted Telephone Interview technique) con oporte Omnibus Phonebus de Taylor Ne/son Sofres Market Research. Resultados: De los 4.949 sujetos incluidos en el análisis. un 21,6% (IC 95% 20,4- 22,7%) refirieron ser alérgicos. La prevalencia fue mayor en mujeres (24,6%), en el grupo de 18 a 24 años de edad (26.9%) y en poblaciones de más de 500.000 habitantes (24,3%). mientras que fue menor en los varones (18,3%), en la región norte-centro ( 17 ,8%) y en poblaciones con menos de 10.000 habitantes ( 18.7% ). o hubo diferencia significativa en relación al nivel socioeconómico. La rinoconjuntivitis fue la manifestación alérgica más frecuente (45,4%) seguida del asma bronquial (24.9% ), la urticaria (24.6% ), la dermatitis (21,5%) y el angioederna (6% ). Las tres causas más frecuente de alergia fueron con diferencia los pólenes (31,5%). los medicamento (29,4%) y los ácaros del polvo domé tico (25.3%). Mucho menos frecuentes fueron los animales (6,8%). los metales (4.9%). los alimentos (4.8%), los hongos (3%), las picadura de insecto (2.5%), la exposición al sol (1,9%) y el látex (0,8%). Conclusiones: La prevalencia de alergia en la población adulta española es del 21,6%, y es más frecuente en las mujeres y en los núcleos urbanos de más de 500.000 habitantes. La manifestación más frecuente es la rinoconjuntivitis. Las manifestaciones cutáneas de la alergia no son despreciables. Las causas más frecuentes de alergia con los aeroalérgeno (pólenes y ácaros) y lo medicamentos (AU)

Background: In spite of the worldwide increase in allergic diseases over the recent years, few epidemiological studies have been conducted in Spain. Objective: We wanted to establish the real prevalence of allergy in a sample of adult general population. We then wanted to describe the profile. the causes and the type of caused disease. Methods: We conducted a population-based study among adults in Spain. We questioned 5003 individuals after calculating a simple size for a máximum undetermination level of (p = 50%). assuming a 1.4 error for global results and a 95% confidence interval (95% CI) l. Five thousands and three individual: were randomly selected from the telephone directory and matched according to sex, age and area. The phone survey was performed with each individual employing the Computer-assisted Telephone lnterview technique supported by Taylor elson Phonebus Company (Barcelona, Spain). Results: We found a 21.6% (95% CI: 20.4-22, 7%) prevalence of allergy. The prevalence was higher in wornen (24.6%) than in men (18.3%). Allergy condition was higher from 18 to 24 years old (26.9%). As it was expected. the prevalence was also higher in urban cities > 500.000 habitants (24.3%) than in rural cities with less than 10.000 habitants ( 18. 7% ). We did not find differences among economical status. The most cornrnon manifestation of allergic disease was rhinoconjunctivitis (45..+%) followed by bronchial asthrna (24.99'c), urticaria (24.6%). Dermatitis (21.5% ), and angioedema (6

Use of a long-acting gonadotrophin-releasing hormone analogue in a postmenopausal woman with hyperandrogenism due to a hilus cell tumour.

OBJECTIVE: The aim of this study was to prove the utility of GnRH analogues for the suppression of androgen secretion in a postmenopausal woman with a suspected virilizing ovarian tumour. DESIGN AND METHODS: We present a case of a 72-year-old woman with virilization of recent onset. Hormonal studies revealed a fourfold increase in serum testosterone levels, normal dehydroepiandrosterone sulphate concentrations and high levels of serum 17-hydroxyprogesterone levels. Computed axial tomography scan of the ovaries was normal and the adrenal glands showed a discrete enlargement. The long-acting GnRH analogue, triptorelin, was injected initially (3.75mg i.m.) and serum hormone levels were measured weekly throughout one month. RESULTS: GnRH produced a decrease in serum testosterone levels to normal values, in parallel with the suppression of serum LH and FSH concentrations. The patient was treated for three months with triptorelin and she experienced an amelioration of the hyperandrogenic symptoms. In order to achieve a diagnosis, the patient was submitted to a laparotomy that revealed a small hilus cell tumour in the left ovary. CONCLUSION: GnRH analogues may offer a good therapeutic option in some states of gonadotrophin-dependent hyperandrogenism of ovarian origin.

[Necrotizing fasciitis as complication of percutaneous endoscopic gastrostomy]. / Fascitis necrotizante como complicación de gastrostomía endoscópica percutánea.

Necrotizing fasciitis (NF) is a rare clinical entity. We describe a case associated with a percutaneous endoscopic gastrotomy (PEG).

[Investigation of the efficacy and tolerability of azelastine nasal spray versus ebastine tablets in patients with seasonal allergic rhinitis]. / Investigación de la eficacia y tolerabilidad de azelastina spray nasal versus ebastina comprimidos en pacientes con rinitis alérgica estacional.

The efficacy and safety of the nasally administered histamine H1 receptor blocking drug Azelastine was investigated in an open, multicenter, randomized comparative trial with Ebastine in seasonal allergic rhinitis. 110 patients in two parallel groups were treated for 14 days and efficacy was assessed by the physician using a rating scale measuring 10 nasal and ocular symptoms of seasonal rhinitis (0 = absent, 1 = mild, 2 = moderate, 3 = severe). Tolerability was measured on the basis of reported adverse events. Both treatment groups had dramatic reductions in the physician's total symptom score following treatment (p < 0.0005). There was no significant difference between the two groups. Changes in individual rhinitis symptoms showed no differences between the two groups. During treatment, 19 patients had at least one adverse event, 13 in Azelastine group and 6 in Ebastine group; all were mild. The most frequent adverse events reported were somnolence (4 cases in Ebastine group) and a bitter taste (4 patients in the Azelastine group). In conclusion, the results of the study on 110 patients suggest that both Azelastine and Ebastine are effective treatments of the symptoms of seasonal allergic rhinitis. Both drugs were well tolerated.