Nutritional Quality of Conventional, Organic, and Hydroponic Tomatoes Commercialized in Quito, Ecuador.

The consumption of natural foods is increasingly high, and in recent years, consumers have preferred foods from systems with responsible management of natural resources (organic, hydroponic). However, there are still contradictions regarding the nutritional content of products from these different types of crops. Our study aims to compare, for the first time, the content of antioxidants (ascorbic acid, lycopene, total phenolics, essential fatty acids), micronutrients (copper, iron, manganese, zinc), contaminants (cadmium and lead), and free radical scavenging activity between conventional, organic, and hydroponic tomatoes (Solanum lycopersicum) sold in markets in Quito, Ecuador. Ascorbic acid and lycopene were determined by HPLC/UV-Vis. Total phenolics (Folin-Ciocalteu method) and free-radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl method) were determined via UV-Vis spectrophotometry. Lipid profiles were determined as fatty acid methyl esters through a GC-FID. Trace metals were determined using FAAS (micronutrients), and GFAAS (pollutants). No significant differences (p > 0.05) between antioxidant and micronutrient content among the three types of tomatoes were found. Regarding cadmium and lead, the contents were below the Codex Alimentarius threshold limits. Finally, free radical scavenging activity varied slightly (organic > hydroponic > conventional). Although the samples showed certain differences in antioxidant content, none of the tomato types could be considered nutritionally better because of the high variability of the results.

Total mercury and fatty acids content in selected fish marketed in Quito - Ecuador. A benefit-risk assessment.

Total mercury and fatty acids contents were determined in muscles of croaker, snapper, dolphinfish, blue marlin, and shark, from different markets in the Metropolitan District of Quito, Ecuador. Fifty-five samples were collected and analyzed for total mercury using cold vapor atomic fluorescence spectrometry, and the fatty acids were analyzed using gas chromatography equipped with a flame ionization detector. The lowest total mercury levels were found in snapper [0.041 µg·g-1 wet weight (ww)] while blue marlin showed the highest (5.883 µg·g-1 ww). EPA + DHA ranged from 1.0 mg·g-1 in snapper to 2.4 mg·g-1 in shark. A high omega-3/omega-6 ratio was found for all fish types; however, the HQEFA for the benefit-risk ratio was above 1, suggesting an evident risk to human health. Based on our results, consumption of croaker and dolphinfish is recommended up to one serving per week, considering the importance of EFAs intake and avoiding fish with elevated MeHg content. Therefore, Ecuadorian authorities could enhance public standards for seafood safety and develop consumer advice for pregnant women and young children to determine good fish choices or those to avoid.

Mutations associated with Helicobacter pylori antimicrobial resistance in the Ecuadorian population.

AIMS: We described the presence of Helicobacter pylori (HP) and estimated the prevalence of primary and secondary resistance using molecular detection in gastric biopsies of Ecuadorian patients. METHODS AND RESULTS: 66.7% (238/357) of the patients demonstrated the presence of HP using CerTest qPCR. Of these, 69.79% (104/149) were without previous HP eradication treatment and 64.42% (134/208) with prior HP eradication treatment. The mutation-associated resistance rate for clarithromycin was 33.64% (primary resistance) and 32.82% (secondary resistance), whereas that in levofloxacin the primary and secondary resistance was 37.38% and 42%, respectively. For tetracycline and rifabutin, primary and secondary resistance was 0%. Primary and secondary resistance for metronidazole and amoxicillin could not be evaluated by genotypic methods (PCR and sequencing). CONCLUSIONS: The analysis of mutations in gyrA, 23S rRNA and 16S rRNA is useful to detect bacterial resistance as a guide for eradication therapy following failure of the first-line regimen. SIGNIFICANCE AND IMPACT OF THE STUDY: This study carried out in an Ecuadorian population indicates that the resistance of HP to first-line antibiotics is high, which may contribute to the high rates of treatment failure, and other treatment alternatives should be considered.

Determination of cadmium and lead in tomato (Solanum lycopersicum) and lettuce (Lactuca sativa) consumed in Quito, Ecuador.

Vegetables are one of the most important components in the human diet, but despite their multiple nutritional components, studies have demonstrated the presence of trace metals in their edible parts. In Ecuador, two of the most consumed crops are tomato (Solanum lycopersicum) and lettuce (Lactuca sativa). The importance of these two crops in the Ecuadorian diet, especially in large and touristic locations like the Metropolitan District of Quito, implies food safety-related concerns for locals and visitors. However, no previous studies have quantified the cadmium and lead levels in these two vegetables using samples from Quito markets. Thus, the aim of this study was to determine the cadmium and lead content in both tomato and lettuce products from main nonorganic and organic markets in Quito using a graphite furnace atomic absorption spectrophotometer. The results showed that the cadmium levels were lower than 0.058 in tomatoes and 0.034 mg/kg in lettuce, which are under the respective threshold values (0.100 and 0.200 mg/kg). Regarding lead, levels lower than 0.066 mg/kg were detected in lettuce, which did not exceed the CXS 193-1995 threshold value, while levels in tomatoes were near or exceeded the threshold value (0.100 mg/kg) from four markets (0.209, 0.162, 0.110, 0.099 mg/kg), suggesting a possible risk from tomato consumption. In addition, most vegetables marketed as organic had higher metal content than those coming from nonorganic markets. Based on these results, local health and commercial control authorities should monitor contaminants in food products sold in Quito and other places in Ecuador to ensure their safety.

Optimization of a Digestion Method to Determine Total Mercury in Fish Tissue by Cold Vapor Atomic Fluorescence Spectrophotometry.

Several microwave-assisted digestion methods were tested at the Centro de Estudios Aplicados en Química laboratory in Quito, Ecuador, to determine the accuracy and performance efficiency of the mineralization process for the determination of total mercury in fish tissue by cold vapor atomic fluorescence spectrophotometry. The use of MARSEasyPrep high-pressure vessels, low amounts of reagents (1 cm3 HNO3, 1 cm3 H2O2, and 1 cm3 HClO4), an irradiation temperature of 210 °C, and 35 min of mineralization time resulted in accurate performance, with recoveries of certified reference material DORM-4 between 90.1% and 105.8%. This is better than the Association of Official Analytical Chemists 2015.01 method, which has a reported accuracy of 81%. The repeatability precision and intermediate precision were established at three concentration levels (0.167, 0.500, and 0.833 mg·kg-1) and expressed as the percentage of the relative standard deviation ranging from 1.5% to 3.0% and 1.7% to 4.2%, respectively. Further, the method was satisfactorily applied to analyze fortified samples of tilapia (Oreochromis niloticus), with recoveries ranging from 98.3% to 104.3%. The instrumental limits of detection and quantification were 0.118 µg·dm-3 and 0.394 µg·dm-3, respectively.

Alkaline Extraction for Lead Determination in Different Types of Commercial Paints.

In 2017, the World Health Organization and the United Nations Environment Programme formed the Global Alliance to Eliminate Lead Paint. All alliance member countries have pledged to develop control regulations that include lead threshold limits. To improve regulations and demonstrate compliance of paint industry products, it is necessary to have adequate, locally applicable methodologies. In this sense, the main objective of this research was to validate the methodology of alkaline extraction for the quantification of lead in ten different types of Ecuadorian commercial paints using flame atomic absorption spectrophotometry. Two hundred and fifty samples from different paint industry products were analyzed, and the results were used to evaluate the method's performance and robustness. It was determined that the method could be applied for lead concentrations above 100 mg·kg-1, and results showed relative standard deviation values lower than 14.8% and fortification recoveries between 80.3 and 119.4%, fulfilling the acceptance criteria established in the Environmental Protection Agency's lead-based Paint Laboratory Operations Guidelines.

Distribution, Contents, and Health Risk Assessment of Cadmium, Lead, and Nickel in Bananas Produced in Ecuador.

In this study, cadmium (Cd), nickel (Ni), and lead (Pb) contents were analyzed in sixteen banana composite samples from different commercial establishments from eleven Ecuadorian production provinces using graphite furnace atomic absorption spectrophotometry. The concentrations (fresh weight) in the samples collected (9.3-47.3 µg·kg-1 for Cd, 16.1-105.6 µg·kg-1 for Ni, and 36.9-538.0 µg·kg-1 for Pb) were used to calculate the estimated daily intake (EDI), target hazard quotient (THQ), and target carcinogenic risk (CR) associated with dietary exposure to these potentially toxic metals. Cd and Ni results showed that every sample had EDIs lower than the oral reference dose and THQ values lower than 1, demonstrating that there was no non-carcinogenic risk related to the exposure to Cd and Ni. In the case of Pb, two EDIs results were higher than the reference dose, also their corresponding THQ values were higher than 1. The lead CR in all samples was less than 1 × 10-4, the upper limit used for acceptable cancer risk. Thus, there is no significant health risk to the consumer associated with bananas with contamination levels of Cd, Ni, but there is Pb risk for toddlers (12 kg of body weight) intake comparable to the one detected in the present study.

Availability, diversification and versatility explain human selection of introduced plants in Ecuadorian traditional medicine.

Globally, a majority of people use plants as a primary source of healthcare and introduced plants are increasingly discussed as medicine. Protecting this resource for human health depends upon understanding which plants are used and how use patterns will change over time. The increasing use of introduced plants in local pharmacopoeia has been explained by their greater abundance or accessibility (availability hypothesis), their ability to cure medical conditions that are not treated by native plants (diversification hypothesis), or as a result of the introduced plants' having many different simultaneous roles (versatility hypothesis). In order to describe the role of introduced plants in Ecuador, and to test these three hypotheses, we asked if introduced plants are over-represented in the Ecuadorian pharmacopoeia, and if their use as medicine is best explained by the introduced plants' greater availability, different therapeutic applications, or greater number of use categories. Drawing on 44,585 plant-use entries, and the checklist of >17,000 species found in Ecuador, we used multi-model inference to test if more introduced plants are used as medicines in Ecuador than expected by chance, and examine the support for each of the three hypotheses above. We find nuanced support for all hypotheses. More introduced plants are utilized than would be expected by chance, which can be explained by geographic distribution, their strong association with cultivation, diversification (except with regard to introduced diseases), and therapeutic versatility, but not versatility of use categories. Introduced plants make a disproportionately high contribution to plant medicine in Ecuador. The strong association of cultivation with introduced medicinal plant use highlights the importance of the maintenance of human-mediated environments such as homegardens and agroforests for the provisioning of healthcare services.

The andean anticancer herbal product BIRM causes destabilization of androgen receptor and induces caspase-8 mediated-apoptosis in prostate cancer.

BIRM is an anticancer herbal formulation from Ecuador. Previous study established its antitumor and antimetastatic activity against prostate cancer models. The activity of BIRM against human prostate cancer (PCa) cells was investigated to uncover its mechanism of antitumor activity. In androgen receptor (AR)-expressing PCa cells BIRM was 2.5-fold (250%) more cytotoxic in presence of androgen (DHT) compared to cells grown in the absence of DHT. In AR-positive cells (LAPC-4 and LNCaP) BIRM caused a dose and time-dependent down-regulation of AR and increased apoptosis. Exposing cells to BIRM did not affect the synthesis of AR and AR promoter activity but increased degradation of AR via proteasome-pathway. BIRM caused destabilization of HSP90-AR association in LAPC-4 cells. It induced apoptosis in PCa cells by activation of caspase-8 via death receptor and FADD-mediated pathways. A synthetic inhibitor of Caspase-8 cleavage (IETD-CHO) aborted BIRM-induced apoptosis. The effect of BIRM on AKT-mediated survival pathway in both AR+ and AR- negative (PC-3 and DU145) showed decreased levels of p-AKTser 473 in all PCa cell lines. BIRM dosed by oral gavage in mice bearing PC-3ML tumors showed selective efficacy on tumor growth; before tumors are established but limited efficacy when treated on existing tumors. Moreover, BIRM inhibited the LNCaP tumor generated by orthotropic implantation into dorsal prostate of nude mice. Partial purification of BIRM by liquid-liquid extraction and further fractionation by HPLC showed 4-fold increased specific activity on PCa cells. These results demonstrate a mechanistic basis of anti-tumor activity of the herbal extract BIRM.

A taxonomic comparison of local habitat niches of tropical trees.

The integration of ecology and evolutionary biology requires an understanding of the evolutionary lability in species' ecological niches. For tropical trees, specialization for particular soil resource and topographic conditions is an important part of the habitat niche, influencing the distributions of individual species and overall tree community structure at the local scale. However, little is known about how these habitat niches are related to the evolutionary history of species. We assessed the relationship between taxonomic rank and tree species' soil resource and topographic niches in eight large (24-50 ha) tropical forest dynamics plots. Niche overlap values, indicating the similarity of two species' distributions along soil or topographic axes, were calculated for all pairwise combinations of co-occurring tree species at each study site. Congeneric species pairs often showed greater niche overlap (i.e., more similar niches) than non-congeneric pairs along both soil and topographic axes, though significant effects were found for only five sites based on Mantel tests. No evidence for taxonomic effects was found at the family level. Our results indicate that local habitat niches of trees exhibit varying degrees of phylogenetic signal at different sites, which may have important ramifications for the phylogenetic structure of these communities.

Soil resources and topography shape local tree community structure in tropical forests.

Both habitat filtering and dispersal limitation influence the compositional structure of forest communities, but previous studies examining the relative contributions of these processes with variation partitioning have primarily used topography to represent the influence of the environment. Here, we bring together data on both topography and soil resource variation within eight large (24-50 ha) tropical forest plots, and use variation partitioning to decompose community compositional variation into fractions explained by spatial, soil resource and topographic variables. Both soil resources and topography account for significant and approximately equal variation in tree community composition (9-34% and 5-29%, respectively), and all environmental variables together explain 13-39% of compositional variation within a plot. A large fraction of variation (19-37%) was spatially structured, yet unexplained by the environment, suggesting an important role for dispersal processes and unmeasured environmental variables. For the majority of sites, adding soil resource variables to topography nearly doubled the inferred role of habitat filtering, accounting for variation in compositional structure that would previously have been attributable to dispersal. Our results, illustrated using a new graphical depiction of community structure within these plots, demonstrate the importance of small-scale environmental variation in shaping local community structure in diverse tropical forests around the globe.

Assessment of anti-protozoal activity of plants traditionally used in Ecuador in the treatment of leishmaniasis.

AIM OF THE STUDY: For the assessment of the in vitro anti-protozoal potential of plants traditionally used in Ecuador in the treatment of leishmaniasis, a combined approach based on interviews with healers as well as a literature search was carried out. MATERIALS AND METHODS: From three regions of Ecuador, 256 local healers called "Agents of Traditional Medicine" (ATMs) were interviewed about their knowledge of the use of plants to treat and heal the illness recognized by the ATMs as leishmaniasis. From literature sources, 14 plants were identified as being used in the treatment of leishmaniasis. Subsequently, plant material was collected from a representative selection of 39 species. A total of 140 extracts were screened in vitro against Leishmania donovani, Plasmodium falciparum, Trypanosoma brucei rhodesiense and Trypanosoma cruzi. Additionally, these extracts were evaluated for their anti-microbial activities using five gram-positive and -negative bacteria as well as Candida albicans. RESULTS AND CONCLUSIONS: The survey resulted in 431 use-records for 145 plant-taxa used for the treatment of leishmaniasis. The 10 most frequently reported taxa accounted for 37.7% of all records. In the case of leishmaniasis, activity was observed for Elephantopus mollis, Minquartia guianensis, Bocconia integrifolia, Gouania lupuloides, Scoparia dulcis, an as-yet-unidentified species of Piper and Brugmansia. For the leaves of M. guianensis and the twigs and bark of G. lupuloides a good selectivity index (SI) was found. IC(50) values and the SI of active plant extracts are presented.

[Clinical characteristics of the late-onset epilepsy in Mexico to the beginning of the new millennium: 455 cases]. / Características clínicas de la epilepsia de inicio tardío en México al principio del nuevo milenio: 455 casos.

INTRODUCTION: Epilepsy is a multifactorial disorder, and several factors can modify its prevalence in different regions. Among these, local culture, public health policies and survival rate can be cited. Alongside, the cause of epilepsy may be different according to time and geographic registries. In Mexico, neurocysticercosis remains a leading cause of seizures. Nonetheless, lifestyle changes and the increase in life expectancy have fostered the incidence of stroke. Both diseases are the main underlying disorders causing epilepsy in Mexico. Lately, their respective incidence is being reversed, and therefore their role is gradually interchanging. OBJECTIVES: To describe and assess the epidemiological and clinical features of a sample of Mexican patients with late-onset seizures. MATERIAL AND METHODS: A group of 455 patients aged over 20 years old was recruited from ten different centers nationwide. The study included patients with onset of epilepsy from year 2000 on, and clinical features of seizures were recorded for every patient, electroencephalogram (EEG) and brain computed tomography (CT) were performed. RESULTS: No gender-related differences were observed. Age distribution was as follows: the highest incidence occurred in the third decade of life and 18% of the patients were aged above 60 years old. Generalized seizures were recorded in 49% of the patients. Pharmacological management used a single drug in 83% of the patients and the most frequently used drug was diphenylhydantoine (PHT) and the second was carbamazepine (CBZ). Abnormal electroencephalographic findings were recoded in 66% of the cases. Concerning etiologies, the first cause was neurocysticerosis in 21% of the cases, followed by stroke in 17% of them. No cause could be found in 49% of the patients. These findings slightly differ from those of other centers in developed countries. CONCLUSIONS: In the last decades, the societal changes in the country have greatly influence the shift in the underlying causes of late-onset seizures. Even if neurocysticercosis stands still as the first cause, its frequency has declined by more than 50% while the increase of stroke incidence has boosted its etiological role and their difference is now statistically non-significant.

Soil nutrients influence spatial distributions of tropical tree species.

The importance of niche vs. neutral assembly mechanisms in structuring tropical tree communities remains an important unsettled question in community ecology [Bell G (2005) Ecology 86:1757-1770]. There is ample evidence that species distributions are determined by soils and habitat factors at landscape (<10(4) km(2)) and regional scales. At local scales (<1 km(2)), however, habitat factors and species distributions show comparable spatial aggregation, making it difficult to disentangle the importance of niche and dispersal processes. In this article, we test soil resource-based niche assembly at a local scale, using species and soil nutrient distributions obtained at high spatial resolution in three diverse neotropical forest plots in Colombia (La Planada), Ecuador (Yasuni), and Panama (Barro Colorado Island). Using spatial distribution maps of >0.5 million individual trees of 1,400 species and 10 essential plant nutrients, we used Monte Carlo simulations of species distributions to test plant-soil associations against null expectations based on dispersal assembly. We found that the spatial distributions of 36-51% of tree species at these sites show strong associations to soil nutrient distributions. Neutral dispersal assembly cannot account for these plant-soil associations or the observed niche breadths of these species. These results indicate that belowground resource availability plays an important role in the assembly of tropical tree communities at local scales and provide the basis for future investigations on the mechanisms of resource competition among tropical tree species.