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Abstract The Llanquihue lake is included in the called Araucanian or Nord Patagonian lakes located between 38-41° S. These lakes are characterized by their oligo-mesotrophic status due to human intervention which takes to the increase in nutrients inputs from industries and towns. Effects on zooplankton assemblages are observed with marked increase of daphnids abundance. The aim of the present study is to analyze the trophic status and zooplankton relative abundance in different bays of Llanquihue lake. It was found direct associations between chlorophyll a with daphnids percentage, total dissolved nitrogen with reactive soluble phosphorus nitrogen/phosphorus molar radio with cyclopoids percentage, and an inverse relation between daphnids and calanoids percentages. The occurrence of three kinds of microcrustacean assemblages and environmental conditions was evidenced: the first one with high calanoids percentage, low species number and low chlorophyll and nutrients concentration, a second with moderate chlorophyll and nutrients concentration and moderate daphnids percentage; high species number and a third site with high chlorophyll and nutrients concentration, high daphnids percentage and high species number. Daphnids increase under mesotrophic status, agree with similar results observed for southern Argentinean and New Zealand lakes.

Background: Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is, in turn, altering the landscape of disease risk for human populations that are brought into novel contact with the vectors and the diseases they carry. Sand flies in the genera Lutzomyia and Pintomyia are vectors of serious disease-causing agents such as Leishmania (the etiological agent of leishmaniasis) and may be expanding their range in the face of climate change. Understanding the climatic conditions that vector species both tolerate physiologically and prefer behaviorally is critical to predicting the direction and magnitude of range expansions and the resulting impacts on human health. Temperature and humidity are key factors that determine the geographic extent of many arthropods, including vector species., Methods: We characterized the habitat of two species of sand flies, Lutzomyia longipalpis and Pintomyia evansi. Additionally, we studied two behavioral factors of thermal fitness-thermal and humidity preference in two species of sand flies alongside a key aspect of physiological tolerance-desiccation resistance., Results: We found that Lu. longipalpis is found at cooler and drier conditions than Pi. evansi. Our results also show significant interspecific differences in both behavioral traits, with Pi. evansi preferring warmer, more humid conditions than Lu. longipalpis. Finally, we found that Lu. longipalpis shows greater tolerance to extreme low humidity, and that this is especially pronounced in males of the species., Conclusions: Taken together, our results suggest that temperature and humidity conditions are key aspects of the climatic niche of Lutzomyia and Pintomyia sand flies and underscore the value of integrative studies of climatic tolerance and preference in vector biology., (© 2024. The Author(s).)

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder without a cure, despite the enormous number of investigations and therapeutic approaches. AD is a consequence of microglial responses to "damage signals", such as aggregated tau oligomers, which trigger a neuro-inflammatory reaction, promoting the misfolding of cytoskeleton structure. Since AD is the most prevalent cause of dementia in the elderly (>60 years old), new treatments are essential to improve the well-being of affected subjects. The pharmaceutical industry has not developed new drugs with efficacy for controlling AD. In this context, major attention has been given to nutraceuticals and novel bioactive compounds, such as molecules from the Andean Shilajit (AnSh), obtained from the Andes of Chile. Primary cultures of rat hippocampal neurons and mouse neuroblastoma cells were evaluated to examine the functional and neuroprotective role of different AnSh fractions. Our findings show that AnSh fractions increase the number and length of neuronal processes at a differential dose. All fractions were viable in neurons. The AnSh fractions inhibit tau self-aggregation after 10 days of treatment. Finally, we identified two candidate molecules in M3 fractions assayed by UPLC/MS. Our research points to a novel AnSh-derived fraction that is helpful in AD. Intensive work toward elucidation of the molecular mechanisms is being carried out. AnSh is an alternative for AD treatment or as a coadjuvant for an effective treatment.

To analyze the mechanisms involved in anthracene (ANT) degradation in the marine alga Ulva lactuca , total RNA was obtained from the alga cultivated without ANT and with 5 μM of ANT for 24 h, and transcriptomic analyses were performed. A de novo transcriptome was assembled, transcripts differentially expressed were selected, and those overexpressed were identified. Overexpressed transcripts potentially involved in ANT degradation were: one aromatic ring dioxygenase, three 2-oxoglutarate Fe (II) dioxygenases (2-OGDOs), and three dienelactone hydrolases that may account for anthraquinone, phthalic anhydride, salicylic acid, and phthalic acid production (pathway 1). In addition, two flavin adenine dinucleotide (FAD)-dependent monooxygenases, four cytP450 monooxygenases, two epoxide hydrolase, one hydroxyphenylpyruvic acid dioxygenase (HPPDO), and two homogentisic acid dioxygenases (HGDOs) were identified that may also participate in ANT degradation (pathway 2). Moreover, an alkane monooxygenase (alkB), two alcohol dehydrogenases, and three aldehyde dehydrogenases were identified, which may participate in linear hydrocarbon degradation (pathway 3). Furthermore, the level of transcripts encoding some of mentioned enzymes were quantified by qRT-PCR are in the alga cultivated with 5 μM of ANT for 0-48 h, and those more increased were 2-OGDO, HGDO, and alkB monooxygenase. Thus, at least three pathways for ANT and linear hydrocarbons degradation may be existed in U. lactuca . In addition, ANT metabolites were analyzed by gas chromatography and mass spectrometry (GC-MS), allowing the identification of anthraquinone, phthalic anhydride, salicylic acid, and phthalic acid, thus validating the pathway 1., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 González, Osorio, Romero, Méndez, Sepúlveda, Laporte, Gutierrez-Cutiño, Santander, Castro-Nallar and Moenne.)

Microplastics (MPs) have been recognized as one of the most ubiquitous environmental pollutants globally. They have been found in all ecosystems studied to date, threatening biological diversity, ecosystem functioning and human health. The present study aimed to elucidate the environmental and anthropogenic drivers of MP dynamics in the whole catchment of the Biobío river, one of the largest rivers in South America. MP concentration and characteristics were analysed in 18 sites subjected to different sources of pollution and other human-related impacts. The sampling sites were classified in relation to altitudinal zones (highland, midland and lowland) and ecosystem types (fluvial and reservoir), and different water and territorial environmental variables were further collated and considered for analysis. Seven types of microplastic polymers were identified in the samples analysed, with a catchment mean (±SE) MP concentration of 22 ± 0.4 particles m -3 , and MP presence being significantly higher in lowlands (26 ± 2 particle m -3 ) and in reservoirs (42 ± 14 particle m -3 ). The most abundant type of MP was fragments (84%), with a mean concentration of 37 ± 6 particles m -3 . Overall, MP concentrations were low compared to those found in other studies, with a strong influence of human population size., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Recurrence and resistance of Candida spp. infections is associated with the ability of these microorganisms to present several virulence patterns such as morphogenesis, adhesion, and biofilm formation. In the search for agents with antivirulence activity, essential oils could represent a strategy to act against biofilms and to potentiate antifungal drugs., Objective: To evaluate the antivirulence effect of Origanum vulgare L. essential oil (O-EO) against Candida spp. and to potentiate the effect of fluconazole and nystatin., Methods: The effect of O-EO was evaluated on ATCC reference strains of C. albicans and non-albicans Candida species. Minimum inhibitory concentration (MIC) was determined through broth microdilution assay. Adhesion to microplates was determined by crystal violet (CV) assay. An adapted scratch assay in 24-well was used to determine the effect of essential oil on biofilms proliferation. Viability of biofilms was evaluated by MTT reduction assay and through a checkerboard assay we determined if O-EO could act synergistically with fluconazole and nystatin., Results: MIC for C. albicans ATCC-90029 and ATCC-10231 was 0.01 mg/L and 0.97 mg/L, respectively. For non-albicans Candida strains MIC values were 2.6 mg/L for C. dubliniensis ATCC-CD36 and 5.3 mg/L for C. krusei ATCC-6258. By using these concentrations, O-EO inhibited morphogenesis, adhesion, and proliferation at least by 50% for the strains assayed. In formed biofilms O-EO decreased viability in ATCC 90029 and ATCC 10231 strains (IC50 7.4 and 2.8 mg/L respectively). Finally, we show that O-EO interacted synergistically with fluconazole and nystatin., Conclusions: This study demonstrate that O-EO could be considered to improve the antifungal treatment against Candida spp., (© 2022. The Author(s).)

Black carbon (BC) has been measured in Antarctica's air, and its global warming effect can potentially speed up the ice melting in the most solid water reservoir of the planet. However, the primary responsible sources are not well evidenced in this region. The dispersion of black carbon emissions from the Southern Hemisphere was conducting using atmospheric chemical transport model and we compared the results with satellite registries from March 1st to April 30th in 2014. The emission inventory considered the anthropogenic and biomass burning emissions from global datasets. The largest and most populated cities in Southern Hemisphere showed the higher emission of BC. As a result, the average daily concentrations of atmospheric BC were around 4 ng/m 3 in most regions of Antarctica according to its pristine characteristics. We analyzed fifteen relevant sites in coastal zones of Antartica and some peaks registered by the satellite records were not replicated by model outputs and it was mainly associated with the lack of emissions. Finally, we made simulations in the same period without biomass burning emissions and we observed decreased concentrations of BC in the range of 20-50%. As a result, we show that the black carbon transportation from the continental land to the polar region took place in 17-24 days during the Austral summer and the biomass burning emissions were the primary source. Black Carbon deposition in Antarctica is not permanent, but the uncontrolled emissions from Southern Hemisphere can increase its transportation to the white continent and make its accumulation during the period when the weak polar vortex occurs., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Resinous exudate obtained from the aerial parts of Adesmia boronioides Hook.f. were evaluated to determine anti-phytopathogenic effects. Briefly, resinous exudate was obtained by dipping fresh plant material in dichloromethane; chemical composition was determined by GC-MS; and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated against four phytopathogenic bacteria. Resinous exudate yield was 8.5% (resin/fresh plant), of which esquel-6-en-9-one (14.25%), esquel-7-en-9-one (5.86%), and veratric acid (2.59%) were the effective antibacterial compounds. Tested against Pectobacterium carotovorum subsp. carotovora , Erwinia amylovora , Bacillus subtilis , and Pseudomonas syringae, MICs and MBCs ranged from 16 to 128 µg/mL and 32-256 µg/mL, respectively. These results provide initial evidence that resinous bush A. boronioides is a new and alternative source of substances with agricultural interest.

3-D printing allows for rapid prototyping and manufacture of components in a cost effective and timely manner, becoming a popular technology for oceanographic and maritime engineering applications. However, 3-D printed components are at risk of accumulating marine biofouling. This study examined the antifouling (AF) performance of three Cu-containing 3-D printing polymer filaments for potential marine use. The amount of Cu present in each filament was the primary determinant of AF performance. The lowest Cu-content (30%) filament recording 29% biofouling cover after 1 month and near 100% cover after 3 months. These AF results were comparable to polylactide acid (PLA) and acrylonitrile butadiene styrene (ABS) polymer filament controls. The medium (50%) Cu-content filament remained largely free of biofouling until 3 months (where 48% coverage was observed), after which fouling cover increased to 100% by ∼12 months. The highest Cu-content (80%) filament remained free of all macrofouling for the entire 24 months of the experiment.

The recent isolation of the yeast Saccharomyces eubayanus has opened new avenues in the brewing industry. Recent studies characterized the production of volatile compounds in a handful set of isolates, utilizing a limited set of internal standards, representing insufficient evidence into the ability of the species to produce new and diverse aromas in beer. Using Headspace solid-phase microextraction followed by gas chromatography-mass spectrometry (HS-SPME-GC-MS), we characterized for the first time the production of volatile compounds in 10 wild strains under fermentative brewing conditions and compared them to a commercial lager yeast. S. eubayanus produces a higher number of volatile compounds compared to lager yeast, including acetate and ethyl esters, together with higher alcohols and phenols. Many of the compounds identified in S. eubayanus are related to fruit and floral flavors, which were absent in the commercial lager yeast ferment. Interestingly, we found a significant strain × temperature interaction, in terms of the profiles of volatile compounds, where some strains produced significantly greater levels of esters and higher alcohols. In contrast, other isolates preferentially yielded phenols, depending on the fermentation temperature. This work demonstrates the profound fermentation product differences between different S. eubayanus strains, highlighting the enormous potential of this yeast to produce new styles of lager beers.

A purple cactus pear (Opuntia ficus-indica) extract (CP) was encapsulated in double emulsions (DE) gelled with gelatin (DE-CP-G) and with gelatin and transglutaminase (DE-CP-GT), as well as in a DE with a liquid external aqueous phase (DE-CP), in order to study the retention of betanin as colorant agent. Both gelled DEs showed a predominantly elastic behavior, in contrast with DE-CP. The degradation rate constant of betanin was significantly higher in DE-CP-GT (90.2 x 10-3 days-1) than in DE-CP-G (11.0 x 10-3 days-1) and DE-CP (14.6 x 10-3 days-1) during cold-storage (4 °C). A shift towards yellow color was found in all the systems during cold-storage (4 °C) and after thermal treatment (70°C/30 min), especially in DE-CP-GT, denoting a higher degradation of betanin. Betalamic acid, cyclo-Dopa 5-O-β-glucoside, 17-decarboxy-betanin and neobetanin were identified by UHPLC-MS/MS as degradation products of betanin., Competing Interests: The authors have declared that no competing interests exist.

Melanoma immunotherapy, specifically the autotransplant of dendritic cells charged with tumors antigens, has shown promising results in clinical trials. The positive clinical effects of this therapy have been associated to increased Th17 response and delayed-type hypersensitivity (DTH) against to tumor antigens. Some synthetic compounds, such as diphenylcyclopropenone (DPCP), are capable of triggering a DTH response in cutaneous malignancies and also to induce clinically relevant effects against melanoma. In this work, we evaluated Litre extract (LExT), a standardized extract of a Chilean stinging plant, Lithraea caustic (Litre). As Litre plant is known to induce DTH, we used a murine B16 melanoma model to compare the topical and intratumor efficacy of LExT with synthetic DTH inducers (DPCP and 2,4-dinitrochlorobenzene [DNCB]). LExt contained mainly long chain catechols and sesquiterpenes. The intratumor injection of LExT induced a significant delay in tumor growth, similarly topical treatment of an established tumor with 0.1% LExT ointment induced a growth delay and even tumor regression in 15% of treated animals. No significant changes were observed on the T-cell populations associated to LExT treatment, and neither DNCB nor DPCP were capable to induce none of the LExT-induced antitumoral effects. Interestingly, our results indicate that LExT induces an antitumor response against melanoma in a mouse model and could bring a new -and affordable- treatment for melanoma in humans., (Copyright © 2019 Robles-Planells, Michelson, Mena, Escrig, Rojas, Sanchez-Guerrero, Hernández, Barrera-Avalos, Rojo, Sauma, Kalergis, Imarai, Fernández, Robles, Leiva-Salcedo, Santander, Escobar and Acuña-Castillo.)

In this work the enzyme laccase from Trametes versicolor was used to synthetize 2,6-dimethoxy-4-(phenylimino)cyclohexa-2,5-dienone derivatives. Ten products with different substitutions in the aromatic ring were synthetized and characterized using ¹H- and 13 C-NMR and mass spectrometry. The 3,5-dichlorinated compound showed highest antifungal activity against the phytopathogen Botrytis cinerea , while the p -methoxylated compound had the lowest activity; however, the antifungal activity of the products was higher than the activity of the substrates of the reactions. Finally, the results suggested that these compounds produced damage in the fungal cell wall.

Ampicillin (AMP) is an antibiotic widely used in hospitals and veterinary clinics around the world for treating infections caused by bacteria. Therefore, it is common to find traces of this antibiotic in wastewater from these entities. In this work, we studied the mineralization of this antibiotic in solution as well as the elimination of its antimicrobial activity by comparing different electrochemical advanced oxidation processes (EAOPs), namely electro-oxidation with hydrogen peroxide (EO-H 2 O 2 ), electro-Fenton (EF), and photo electro-Fenton (PEF). With PEF process, a high degradation, mineralization, and complete elimination of antimicrobial activity were achieved in 120-min electrolysis with high efficiency. In the PEF process, fast mineralization rate is caused by hydroxyl radicals (·OH) that are generated in the bulk, on the anode surface, by UV radiation, and most importantly, by the direct photolysis of complexes formed between Fe 3+ and some organic intermediates. Moreover, some products and intermediates formed during the degradation of the antibiotic Ampicillin, such as inorganic ions, carboxylic acids, and aromatic compounds, were determined by photometric and chromatographic methods. An oxidation pathway is proposed for the complete conversion to CO 2 .

The effective removal of organics from winery wastewater was obtained in real residual effluents from the wine industry using anodic oxidation (AO). The effluent had an initial organic load of [COD] 0 of 3490 mg L -1 equal to [TOC] 0 of 1320 mg L -1 . In addition, more than 40 organic compounds were identified by means of GC-MS. Different density currents as well as the addition of electrolytes were tested during electrolysis. The results show the decay of [COD] t by 63.6% when no support electrolyte was added, whereas almost total mineralization and disinfection was reached after adding of 50 mM of sodium sulfate and sodium chloride and applying higher density currents. The presence of sulfate and chloride in large concentration favors the production of oxidants such as hydroxyl radicals and active chlorine species that react with organics in solution. Moreover, the addition of a supporting electrolyte to industrial wastewater increases conductivity, reduces cell potential and therefore, decreases the energy consumption of the AO process., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The elimination of the antibiotic Nafcillin (NAF), which is usually used in hospitals and veterinary clinics around the world, was assessed through a combination of three advanced electrochemical oxidation processes followed by anaerobic digestion process. In the first stage different electrochemical advanced oxidation processes (EAOPs) were used: electro-oxidation with hydrogen peroxide (EO-H 2 O 2 ), electro-Fenton (EF) and Photo electro-Fenton (PEF). After PEF, almost complete and highly efficient degradation and elimination of NAF was achieved, with the concomitant elimination of the associated antimicrobial activity. The fast degradation rate produced by PEF is explained by the oxidative action of hydroxyl radicals (•OH) together with the direct UV photolysis of complexes formed between Fe 3+ and some organic intermediates. Total removal of NAF occurs after 90min of electrolysis by PEF, with the generation of organic intermediates that remain in solution. However, when this post PEF process solution was treated with an anaerobic biological process, the intermediates generated in the electrochemical degradation of NAF were completely eliminated after 24h. The kinetic degradation of NAF as well as the identification/quantification of products and intermediates formed during the degradation of antibiotic, such as inorganic ions, carboxylic acids and aromatic compounds, were determined by chromatographic and photometric methods. Finally, an oxidation pathway is proposed for the complete conversion to CO 2 ., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The Llanquihue lake is included in the called Araucanian or Nord Patagonian lakes located between 38-41° S. These lakes are characterized by their oligo-mesotrophic status due to human intervention which takes to the increase in nutrients inputs from industries and towns. Effects on zooplankton assemblages are observed with marked increase of daphnids abundance. The aim of the present study is to analyze the trophic status and zooplankton relative abundance in different bays of Llanquihue lake. It was found direct associations between chlorophyll a with daphnids percentage, total dissolved nitrogen with reactive soluble phosphorus nitrogen/phosphorus molar radio with cyclopoids percentage, and an inverse relation between daphnids and calanoids percentages. The occurrence of three kinds of microcrustacean assemblages and environmental conditions was evidenced: the first one with high calanoids percentage, low species number and low chlorophyll and nutrients concentration, a second with moderate chlorophyll and nutrients concentration and moderate daphnids percentage; high species number and a third site with high chlorophyll and nutrients concentration, high daphnids percentage and high species number. Daphnids increase under mesotrophic status, agree with similar results observed for southern Argentinean and New Zealand lakes.

Belschmiedia miersii (Gay) Kosterm. (Lauraceae) ("Belloto del Norte") is a little-studied tree endemic of the Central Zone of Chile. Hydrodistillation of leaves and stem bark of B. miersii yielded 0.2% essential oil. GC-MS analysis allowed identification of 31 components. The most abundant compounds were three phenylpropanoids: Sarisan (45.8%), eugenol methyl ether (27.7%) and safrole (5.8%). The oil of B. miersii showed high antioxidant content (TEAC: 750.8 ±9.6 μmol/100 g of essential oil). The anti-phytopathogenic activity was evaluated against pathogens of plants: Fungi (Botrytis cinerea, Gibberella fujikitroi and Phytophthora cinnamomi) and bacteria: (Erwinia carotovora, Pseudomonas syringae and Agrobacterium tumefaciens) . The oil showed anti- phytopathogenic activity against all tested bacteria and fungi, especially against A. tumefaciens (IC₅₀= 5 μg / mL) and P. cinnamomi (IC₅₀ = 200 μg /mL). This study demonstrates that the essential oil of B. iniersii has great potential for applications in food and agricultural industries.

In this communication, we report the springtime variation of the composition of aristolochic acids (AAs) in Aristolochia chilensis leaves and stems. The dominant AA in the leaves of all samples, which were collected between October and December, was AA-I (1), and its concentration varied between 212.6±3.8 and 145.6±1.2 mg/kg and decreased linearly. This decrease occurred in parallel with the increase in AA-Ia (5) concentration from 15.9±0.8 mg/kg at the beginning of October to 96.8±7.8 mg/kg in mid-December. Both acids are enzymatically related by methylation-demethylation reactions. Other AAs also showed important variations: AA-II (2) significantly increased in concentration, reaching a maximum in the first two weeks of November and subsequently decreasing in mid-December to approximately the October levels. The principal component in the AA mixture of the stems was also AA-I (1); similar to AA-II (2), its concentration increased beginning in October, peaked in the second week of November and subsequently decreased. The concentrations of AA-IIIa (6) and AA-IVa (7) in the leaves and stems varied throughout the study period, but no clear pattern was identified. Based on the variation of AAs in A. chilensis leaves and stems during the study period, the reduced contents of non-phenolic AAs and increased concentrations of phenolic AAs are likely associated with a decrease in this plant's toxicity during the spring.

We performed a sequestration study of aristolactams (ALs) from Aristolochia chilensis in Battus polydamas archidamas (Lepidoptera: Papilionidae) by examining the AL content of the plant, fifth instar larvae, osmeterial secretion, pupae, exuviae and feces. Aristolactam-I (AL-I) and aristolactam-II (AL-II) present in A. chilensis are sequestered by fifth instar larvae of B. polydamas archidamas. There is a preferential sequestration of AL-II, or a more efficient metabolization and excretion of AL-I, by the larva. No ALs were found in the osmeterial secretion, pupae and exuviae; in addition, little AL-I and no AL-II were found in larval frass. The two lactams, particularly AL-I, are extensively metabolized to other products in the larva. A reasonable hypothesis is that the ingested ALs are oxidized to their respective aristolochic acids.

Ethnopharmacological Relevance: Psoralea glandulosa L. (Fabaceae) is a medicinal resinous shrub used in Chilean folk medicine as antiseptic in treatment of infections and skin diseases caused by bacteria and fungus., Aim of the Study: To evaluate the in vitro antifungal activity of the resin and the active components from P. glandulosa against clinical yeast isolates., Materials and Methods: Active compounds were obtained of the resinous exudate from aerial parts of P. glandulosa. Eight species of yeast were exposed to the resin and two major compounds. Minimum inhibitory concentration (MIC(80)) was determined according to the standard broth microdilution method., Results: Bakuchiol and 3-hydroxy-bakuchiol demonstrated potent activity with the MIC(80) ranging from 4 to >16 and 0.125 to 16 μg/mL, respectively. The resin had some degree of antifungal activity., Conclusions: The overall results provided important information for the potential application of the 3-hydroxy-bakuchiol from P. glandulosa in the therapy of serious infection and skin diseases caused by clinical yeast., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Introduction: Colorectal cancer (CRC) incidence is rapidly increasing. It has been demonstrated that it can be prevented and cured when the diagnosis is made in early stages., Objective: For this reason it is necessary to apply a screening program in asymptomatic patients., Method: Since 2003, we conducted a CRC screening plan called "Mes del Colon" at Clínica Alemana Santiago. A press and local diffusion campaign was designed. Open to the community CRC talks were scheduled. An ad hoc database was designed. An informed consent was available. Patients older than 50 years and high risk patients were included. Total colonoscopy and a medical interview after the procedure were included in the plan with favorable economic conditions., Results: Since 2003, 1158 patients were included The 1.8% of them were excluded because of incomplete data or because they did not meet the inclusion criteria. The 54% of patients were women. Mean age was 58.4 years old and mean body mass index 25.5 kg/m2. Polipoid lesions were seen in 45% of the patients. Six (1%) of them were adenocarcinomas, 291 (57%) adenomas (98% tubular adenomas), 189 (37%) hyperplastic polyps and 25 (5%) miscellaneous lesions. In this series, the necessary number to investigate for 1 adenoma was 3.9., Conclusions: CRC prevention campaigns are needed due to the continuous increase of the incidence in our country. The detection of precursor or early lesions that are longstanding before becoming advanced cancer allows its treatment avoiding progression.

The insecticidal activity of nine essential oils (EOs) against the house fly (Musca domestica) was evaluated by placing flies in a screw-cap glass jar holding a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC(50)) in 30 min was determined at 26 +/- 1 degrees C. The EOs showed LC(50) values ranging from 0.5 to 46.9 mg/dm(3). The EO from Minthostachys verticillata was the most potent insecticide (LC(50) = 0.5 mg/dm(3)) followed by EOs from Hedeoma multiflora (LC(50) = 1.3 mg/dm(3)) and Artemisia annua (LC(50) = 6.5 mg/dm(3)). The compositions of the nine EOs, obtained by hydrodistillation of medicinal herbs, were analyzed by gas chromatography/mass spectroscopy. These analyses showed that (4R)(+)-pulegone (69.70%), menthone (12.17%), and limonene (2.75%) were the principal components of M. verticillata EO. (4R)(+)-pulegone was also the main constituent (52.80%) of H. multiflora, while artemisia ketone (22.36%) and 1,8-cineole (16.67%) were the major constituents of A. annua EO. The terpene (4R)(+)-pulegone showed a lower toxicity (LC(50) = 1.7 mg/dm(3)) than M. verticillata or H. multiflora EOs. Dimethyl 2,2-dichlorovinyl phosphate, selected as a positive control, showed an LC(50) of 0.5 mg/dm(3). EOs from M. verticillata and H. multiflora show promise as natural insecticides against houseflies.

The compositions of 12 essential oils (EOs) obtained by hydrodistillation of edible fruits and herbs were analyzed by gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of each oil against the house fly Musca domestica was evaluated by placing flies in a glass jar with a screw cap that held a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC(50)) in 30 min was determined at 26 +/- 1 degrees C. Twelve EOs and 17 individual terpenes were assayed against M. domestica, showing LC(50) values ranging from 3.9 to 85.2 and from 3.3 to >100 mg/dm(3), respectively. EO from Citrus sinensis was the most potent insecticide (LC(50 )= 3.9 mg/dm(3)), followed by EOs from C. aurantium (LC(50 )= 4.8 mg/dm(3)) and Eucalyptus cinerea (LC(50 )= 5.5 mg/dm(3)). According to GC/MS analysis, limonene (92.47%), linalool (1.43%), and b-myrcene (0.88%) were the principal components of C. sinensis EO. Limonene was also the principal constituent (94.07%) of C. aurantium, while 1,8-cineole (56.86%) was the major constituent of E. cinerea EO. 1,8-Cineole was most active against M. domestica (LC(50 )= 3.3 mg/dm(3)), while (4R)(+)-limonene, was moderately active (LC(50 )= 6.2 mg/dm(3)). Dimethyl 2,2-dichlorovinyl phosphate (DDVP) selected as a positive control, showed an LC(50) of 0.5 mg/dm(3). EOs from C. sinensis, C. aurantium, and E. cinerea show promise as natural insecticides against houseflies.

Background: The appearance of inverted colonic diverticula (ICD) is similar to that of elevated polypoid lesions. The aim of this study was to describe the endoscopic characteristics of ICD with a view to avoiding misdiagnosis, and to report the frequency of these lesions., Material and Method: Using an endoscopic database, we retrospectively analyzed all patients who underwent colonoscopy at our institution between July 2001 and July 2004. Patients diagnosed with ICD were identified and both patient and ICD characteristics were recorded, including location, endoscopic characteristics, and the presence of synchronous colon polyps., Results: Among the 4508 colonoscopies performed in the selected period, 33 patients (0.7%) were diagnosed with ICD. The mean age was 62.3 years, with a male-to-female ratio of 1:1.2. Most ICD (89%) were in an area of multiple colonic diverticula and 75% were located in the sigmoid colon. One patient had active bleeding directly from the inverted diverticulum and was treated with injection therapy. The endoscopic characteristics of ICDs were described. There were no complications in this series., Conclusions: ICD is a rare endoscopic finding that can be complicated by local bleeding. Misdiagnosis can be dangerous and biopsy or endoscopic resection could lead to serious complications. The endoscopic criteria described should be considered to avoid the complications associated with biopsy or resection.

Background: Gastric cancer has a direct relation with chronic atrophic gastritis (AG) and intestinal metaplasia (IM), considered as preneoplastic lesions. Determination of serum pepsinogen llevéis (PGI) and pepsinogen I / pepsinogen II ratio (PGI/PGII) can detect this conditions; achieving 70-90% of gastric cancer detection in early stages., Aim: To determine the cut-off values for serum PGI and PGI/PGII in Chilean subjects, for the detection of gastric preneoplastic lesions, establishing their sensitivity, specificity, positive (PPV) and negative (NPV) predictive values., Patients and Methods: Prospective study of patients subjected to upper gastrointestinal endoscopy and determination of serum pepsinogen levels. The presence and severity of preneoplastic lesions were compared with serum levels of PGI and PGI/PGII., Results: A total of 56 men and 44 women were studied, with a mean age of 43 (14-77) years. There was a significant association (p <0.001) of PGI and PGI/PGII with AG and IM. We obtained a cut-off value of 2.3 for PGI/PGII (sensitivity =70%>, specificity =92%>, PPV =60%>, NPV =95%) and 36 ng/ml for PGI (sensitivity =62%o specificity =64%o, PPV =20%o, NPV =91%), for detection of moderate to severe AG. No patient with normal mucosa had a PGI <20 ng/ml. The combined criteria of PGI/II < or = 2.3 and/or PGI < or 20 ng/ml, obtained a sensitivity of 85%o, specificity of 92%>, PPV of 65%o, and NPV of 97%o., Conclusions: We confirmed a strict relation ofPGIand PGI/PGIIwith the presence of preneoplastic gastric lesions in Chilean patients.

Objective: To develop, apply, and evaluate an educational model for the primary prevention of sexually transmitted diseases (STDs) and acquired immunodeficiency syndrome (AIDS) that was based on the sexual knowledge, attitudes, and practices (KAPs) of adolescents and on their perceptions and behaviors in this area, with the ultimate goal of helping develop educational tools to prevent infection with STDs and the human immunodeficiency virus (HIV)., Methods: An STD/HIV/AIDS primary prevention model was applied with adolescent schoolchildren (12 to 15 years old) in the canton of Santo Domingo de los Colorados, Ecuador. Two groups with similar characteristics were formed: the experimental group, with 358 students, and the control group, with 288 students. Schools were selected according to inclusion criteria, and adolescents at each school were chosen at random. A discussion guide was applied with 16 focus groups, and the resulting information was used to prepare a KAP survey. After being validated, the KAP survey was applied to the experimental group and to the control group. A prevention education program geared to students and teachers was implemented with the experimental group. Eight months later a second KAP survey was done with the experimental group and the control group. The differences in KAPs before and after the intervention were evaluated using the chi-square test., Results: There were no statistically significant differences between the two groups before the intervention, but afterwards the differences were statistically significant (P = 0.012), with an increase in the knowledge of sexuality and STDs/AIDS in the experimental group, even though the long-term behavior changes have not been evaluated., Conclusions: This study validated a multifactorial STD/AIDS prevention model adapted to the reality of adolescents, and it suggests the possibility of extrapolating this experience more broadly to contexts similar to those of this Ecuador population.

Abdominoscrotal hydrocele represents a very rare eventuality in childhood; nowadays, only 14 cases have been reported in the world literature and the present case is the first one in our country. In this patient the coexistence of a small scrotal hydrocele and cystic mass at the right side is described. The results of the studies and exams are showed, and the type of the surgical excision and its findings are commented. Three theories are the most cited in order to explain its genesis, but the one supported by Laplace's law is very scientific and convincing. At the light of the different cases reported in the literature, a suggested classification is discussed and different entities are analysed in order to get a differential diagnosis; finally, the idoneous surgical therapy is reviewed. Abdominoscrotal hydrocele; differential diagnosis.

Nifedipine, a calcium-blocking agent, inhibits smooth muscle contractions in various organs including gastric muscle in vitro. Despite this, nifedipine has been found to have no effect on gastric emptying in man. We have investigated the effect of nifedipine on gastric emptying of liquids and solids and on gastrointestinal motility in six healthy subjects. For this, isotopic techniques and manometric methods were used. We confirm that nifedipine 30 mg per os does not modify gastric emptying of liquids or solids. By contrast, antral motility was significantly inhibited (P less than 0.05) and duodenal motility increased. These results could be interpreted as (1) gastroduodenal motility changes are not severe enough to alter emptying or (2) isotopic techniques are not sensitive enough to detect subtle changes in gastric emptying.