Inhibition of Aspergillus carbonarius growth and Ochratoxin A production using lactic acid bacteria cultivated in an optimized medium.

The Gram-positive bacteria lactic acid bacteria (LAB) are used in the food industry but are also known for inhibiting certain food spoilage microorganisms, especially fungi. Sources of nitrogen (N) for culture media are generally organic and expensive. Many attempts have been made to formulate economical culture media with alternative N sources obtained from agricultural and industrial byproducts. This study describes the design and optimization of an inexpensive culture medium for Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) MZ809351 strain B31. The culture medium was optimized using statistical experimental designs to identify the factors with the most significant effects on biomass concentration to reduce the overall cost, aiming to obtain a biomass concentration similar to that obtained with the reference LAB culture medium (de Man, Rogosa and Sharpe; MRS). Sodium acetate and magnesium sulfate were the most significant factors (p < 0.005), and their contents were reduced by 22 % and 40 %, respectively, without affecting biomass concentration. Malt germ extract (MGE) was used as an alternative nitrogen source to replace meat extract (ME) and proteose peptone (PP). Through these experiments, the composition of a culture medium that is less expensive than MRS broth was defined, which produced a biomass concentration (3.8 g/L) similar to that obtained with MRS medium. The inhibitory effects of two LAB strains isolated from the Ivory Coast and Mexico on the growth and production of ochratoxin A (OTA) in an ochratoxigenic fungus was tested. The minimum cellular concentration of the LAB to prevent the development of Aspergillus carbonarius Ac 089 and the production of OTA was determined in a model assay in Petri dishes. The conditions to inhibit the germination of A. carbonarius Ac 089 and the production of OTA were found. Using the optimized medium and a ratio of 2 × 104 LAB/spore (1 × 108 CFU/mL) strain B7 (L. plantarum MZ809351) and 2 × 103 LAB/spore (1 × 107 CFU/mL) strain B31 (L. plantarum MN922335) completely inhibited the growth of the fungus. A ratio of 2 × 105 LAB/spore (1 × 109 CFU/mL) was required to inhibit OTA production with strains B7 and B31. This study indicates the potential of cultivating LAB in an optimized and inexpensive culture medium for use as a biological control agent against ochratoxigenic fungi in food.

Metal(loid)s (As, Cd, Cu, and Zn) in three fish species from a dam after a mine-tailing spill: differential bioaccumulation and potential health risk.

The failure of a tailings dam occurred in January 2013 at the Santa María de Otáez mining region (Mexico) released a spill (~ 300,000 m3) on Los Remedios River, which was transported through the San Lorenzo River, and finally to El Comedero (EC) dam. The concentrations of metal(loid)s in the muscle, liver, gills, and guts of three fish species (Cyprinus carpio, Oreochromis aureus, Micropterus salmoides) collected from EC dam were examined twenty months later to assess the performance of the cleaning operations. The bioaccumulation patterns of the metal(loid)s in the tissues were different in the three fish species. Tilapia had the highest Cd (11.23 ± 8.53 µg g-1) and Cu (871 ± 1261 µg g-1) concentrations in the liver, as well as As concentration (83.6 ± 61.7 µg g-1) in the gut, while the highest Zn concentration (745 ± 356 µg g-1) was measured in the gills of the carp. Such variability can be caused by the variant bioavailability of the metal(loid)s and by the feeding habits of each species; and also by the fact that some metals are essential and better regulated by organisms than other non-essential. Compared to a study of tilapia carried out 90 days after mine spill, a decrease was evident in the liver for As, Cd, Cu, and Zn by 129, 5, 10, and 1.7 times, respectively. This revealed that cleaning operations were more efficient for As. The target hazard quotient and the hazard index were < 1, which indicates there will be no risk of consuming muscle in moderated rations of the three fish species.

High accumulation of metals and metalloids in the liver of the blue tilapia (Oreochromis aureus) during a massive mortality event induced by a mine tailing spill.

In this study, the concentration of six metal(loid)s was examined in the fish Oreochromis aureus collected from El Comedero dam during a massive mortality event induced by a mine tailing spill. A major spill (~ 300,000 m3) of waste was released into the San Lorenzo River System following a rupture in the tailing dam of a mining plant in NW Mexico; consequently, the discharged material flowed into El Comedero dam. The accumulation of metal(oid)s in the tissues of O. aureus showed higher levels in the liver than in the guts and muscle. Concentrations in the liver were high (As, 1.1-1063; Cd, 8.9-392; Cu, 372-59,129; Hg, 0.46-19.79; Se, 8.7-748; and Zn, 116-820 µg g-1), revealing that these fish were exposed to high concentrations of these elements. The mortality of fish could have resulted from the combined effect of the six analyzed metal(loid)s, as well as other residues present in mine tailings.

Integrating central nervous system metagenomics and host response for diagnosis of tuberculosis meningitis and its mimics.

The epidemiology of infectious causes of meningitis in sub-Saharan Africa is not well understood, and a common cause of meningitis in this region, Mycobacterium tuberculosis (TB), is notoriously hard to diagnose. Here we show that integrating cerebrospinal fluid (CSF) metagenomic next-generation sequencing (mNGS) with a host gene expression-based machine learning classifier (MLC) enhances diagnostic accuracy for TB meningitis (TBM) and its mimics. 368 HIV-infected Ugandan adults with subacute meningitis were prospectively enrolled. Total RNA and DNA CSF mNGS libraries were sequenced to identify meningitis pathogens. In parallel, a CSF host transcriptomic MLC to distinguish between TBM and other infections was trained and then evaluated in a blinded fashion on an independent dataset. mNGS identifies an array of infectious TBM mimics (and co-infections), including emerging, treatable, and vaccine-preventable pathogens including Wesselsbron virus, Toxoplasma gondii, Streptococcus pneumoniae, Nocardia brasiliensis, measles virus and cytomegalovirus. By leveraging the specificity of mNGS and the sensitivity of an MLC created from CSF host transcriptomes, the combined assay has high sensitivity (88.9%) and specificity (86.7%) for the detection of TBM and its many mimics. Furthermore, we achieve comparable combined assay performance at sequencing depths more amenable to performing diagnostic mNGS in low resource settings.

Solid-state culture of Azospirillum brasilense: a reliable technology for biofertilizer production from laboratory to pilot scale.

A biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. A mathematical model was proposed and validated to evaluate the respirometry trends at laboratory and pilot scale exhibiting similar behavior. The cell viability was (1.3 ± 0.4) × 109 and (1.3 ± 0.3) × 109 colony-forming units per gram of initial dry mass at laboratory and pilot scale, at 36 and 43 h, respectively. A. brasilense maintains its viability twelve months of storage at 4 and 30 °C. This is the first report of A. brasilense being cultivated in SSC under controlled conditions. SSC processes involving unicellular microorganisms with tolerance to agitation are a promising technology to produce biofertilizers.

Effect of perfluorohexane sulfonate on pig oocyte maturation, gap-junctional intercellular communication, mitochondrial membrane potential and DNA damage in cumulus cells in vitro.

Perfluorohexane sulfonate (PFHxS) is one of the most abundant perfluorinated compounds in the environment. Exposure to this compound has been correlated to a decrease in human fertility, although the molecular and cellular mechanisms underlying this correlation have not been described. The adverse reproductive effects of PFHxS could be based on alterations in oocyte maturation, the process rendering oocytes competent for fertilization. The aim of this study was to evaluate the effect of PFHxS on porcine oocyte viability and maturation in vitro, as well as on gap-junctional intercellular communication (GJIC) in cumulus-oocyte complexes (COCs), oocyte mitochondrial membrane potential (mΔΨ) and DNA damage in cumulus cells, as possible mechanisms of action. PFHxS caused cytotoxicity (medium lethal concentration, LC50 = 329.1 µM) and inhibition of oocyte maturation (medium inhibitory concentration, MIC50 = 91.68 µM). GJIC was not affected in exposed COCs. However, the mitochondrial membrane potential was significantly decreased in PFHxS-exposed oocytes at the germinal vesicle breakdown (GVBD) stage. In addition, exposure to PFHxS induced DNA damage in cumulus cells. Thus, inhibition of oocyte maturation by PFHxS could be attributed to a decreased oocyte mΔΨ at the GVBD and to DNA damage of the cumulus cells that support the oocyte.

Bilateral nephrectomy as an extreme measure management for methicillin-resistant staphylococcus aureus (MRSA): A case report.

Methicillin-resistant Staphylococcus aureus (MRSA) infections are cases of urgent management that often leads to hospitalizations in intensive care and prolonged management of antibiotic therapy. In this occasion, we present the case of a 38-year-old female patient with sepsis secondary to banal dermal infection due MRSA that complicates with infectious thrombus of the left renal vein associated with multiple foci of bilateral renal abscesses. As an extreme and exceptional measure, emergency bilateral radical nephrectomy was performed to save the patient's life.

Manifestación de una interacción farmacológica entre rivastigmina y tolterodina en un paciente geriátrico con diagnósticos de Parkinson y vejiga hiperactiva: reporte de caso / Management of the drug interaction between rivastigmine and tolterodine in one elderly patient with Parkinsonand overactive bladder

El uso conjunto de medicamentos anticolinérgicos e inhibidores de la colinesterasa no es recomendado por los fabricantes de los productos, ya que pueden afectar la función cognitiva de los pacientes, esto se ve acentuado en la población geriátrica polimedicada. Uno de los problemas relacionados a la medicación, en los que los farmacéuticos realizan con frecuencia intervenciones, es el número de interacciones farmacológicas potenciales que pueden expresarse con los distintos medicamentos que emplean los pacientes. Presentamos el caso de un paciente con diagnóstico de Parkinson y vejiga neurogénica que presentó pérdida de la concentración y memoria asociada a una interacción farmacológica entre un inhibidor directo de la colinesterasa (rivastigmina) y un anticolinérgico (tolterodina). El mecanismo descrito para la interacción es la disminución del efecto esperado de rivastigmina por efecto de inhibición de la tolterodina en los receptores colinérgicos, impidiendo la liberación de acetilcolina y quitando así el blanco terapéutico de la enzima que se inhibe por efecto de la tolterodina. La intervención oportuna y el manejo adecuado de las interacciones farmacológicas durante la atención sanitaria es de suma importancia para evitar daños en los pacientes, incluido la exacerbación de enfermedades que se encuentran controladas, debido a la adición de otros medicamentos a la farmacoterapia

The use of anticholinergic and cholinesterase inhibitors set is not recommended by drug laboratory producers, because the use of the drugs can affect the cognitive function of the patients, this is more common in the elderly and polymedicated population. For the pharmacist is a challenge to have control of the number of potential drug interactions that can express with the different drugs that the patient has in a prescription. We present a case of an expression of drug-drug interaction between anticholinergic (tolterodine) and direct cholinesterase inhibitor (rivastigmine) in a patient with Parkinson disease and overactive bladder, the outcome of this interaction is the decrease the effect of rivastigmine by inhibition of cholinergic receptors, keep the inhibition of release acetylcholine and remove the target of the enzyme that rivastigmine inhibit, the expression of the interaction in the patient is expressed in loss of concentration and memory, the management and report of this interaction is very important for the patient with control of the disease

Effect of stirring on growth and cellulolytic enzymes production by Trichoderma harzianum in a novel bench-scale solid-state fermentation bioreactor.

A novel bench-scale stirred bioreactor for solid-state fermentation was used to determine the effect of the stirring rate on growth and enzymes production by Trichoderma harzianum PBLA. Lab-scale static tubular bioreactors were first used to assess the effect of bioreactor diameter on heat accumulation, growth, and production of cellulases and xylanases. The increased diameters (1.8-4.2 cm) led to increases in temperature up to 36 °C (at a rate of 1.08 °C/cm), which negatively affected the growth and enzyme production. Afterward, in the bench-scale bioreactor operated at rates up to 3.0 rpm, maximum xylanases production (107 ±â€¯0.3 U/g dm) was attained at rates of 0.5 and 1.0 rpm, reaching a maximum of 34 ±â€¯0.3 °C. Cellulases production was reduced (up to 79%) due to stirring. Therefore, the production of xylanases by T. harzianum can be performed in this cross-flow stirred SSF bioreactor at rates up to 1.0 rpm, avoiding heat accumulation and damage on metabolic activity.

What Limits the Distribution of Liriomyza huidobrensis and Its Congener Liriomyza sativae in Their Native Niche: When Temperature and Competition Affect Species' Distribution Range in Guatemala.

Factors limiting distribution range for most species are generally unknown regardless of whether they are native or invasive. We studied factors that could enable or restrict the distribution of two cosmopolitan invasive leafminer fly species, Liriomyza huidobrensis (Blanchard) and Liriomyza sativae (Blanchard) in their native niche. In order to test which ecological and environmental factors affect leafminer distribution we conducted thermal tolerance assays, sampled along elevation gradients and modeled species distribution. Findings from the field and rearing chambers showed a physiological restriction due to high temperatures for L. huidobrensis at 28-29 °C, above which adult emergence is compromised. We also found that maximum temperatures below 22 °C, typical of tropical highlands, favored L. huidobrensis. L. sativae was found across a wider temperature range (i.e., from 21 to 36 °C) in Guatemala. Our finding of a physiological threshold in temperature for L. huidobrensis may enable us to predict its invasive risk when combined with the environmental conditions at horticultural ports of entry and the global agricultural landscape. Further, it strengthens our predictions on shifts in distribution of the leafminer fly under future climate. We also found a temperature mediated competitive exclusion interaction between the two herbivore species, where L. sativae occurred at temperatures < 22 °C only in the absence of L. huidobrensis. We show that parasitoids had a negative effect on the leafminer flies, which varied with host plant. Finally, we show the importance of taking a multiaspect approach when investigating what limits distribution and invasiveness of a species.

Monitoring of inland waters for culturing shrimp Litopenaeus vannamei: application of a method based on survival and chemical composition.

This study evaluated the suitability of 21 inland waters (16 well waters and 5 surface waters) from Northwest Mexico via short- (48 h) and medium-term (28 days) tests using postlarvae (PL18) of Litopenaeus vannamei. In the short test, survival was assessed at 48 h after shrimp were placed in groups of 10 postlarvae into 2-L containers of inland water, to which they had been previously acclimated. The second, medium-term test consisted of four replicates with 10 postlarvae, and each group was placed in 15-L containers with the treatment water. Weights (initial and final) and survival were evaluated weekly for 28 days. In those waters for which the short test was positive and the medium-term test was negative and which also had a deficiency of potassium and/or magnesium, a third test was conducted. These last waters were supplemented with salts, and the shrimp survival and weights (initial and final) were recorded for 28 days. The water samples from San Jose, Mochicahui, Sinaloa River, Caimanero inner Lagoon, La Pipima, Campo Santa Fe, Escopama, and Fitmar had >60% survival in the short test. The Caimanero inner Lagoon water had the highest survival (87.5 ± 9.6%) and final mean weight (201.3 ± 86.2 mg). In the third test, it was found that shrimp in the water from La Pipima, Campo Santa Fe, and Fitmar exhibited 100% survival for 2 weeks. Finally, in this work, a decision tree to evaluate the suitability of low-salinity water for shrimp farming was proposed, which can be applied in other regions.

Asociación del antecedente transfusional antes de 1994 con hepatitis vírica tipo C en mujeres / Linking hepatitis C virus infection to pre-1994 blood transfusions in female patients

INTRODUCCIÓN La mayor parte de las transfusiones se llevan a cabo en mujeres. La introducción en los bancos de sangre de las técnicas serológicas disminuyó la incidencia de infección por virus de hepatitis C después de una transfusión. En México, las pacientes que se transfundieron antes de 1994 están en riesgo de presentar una infección por virus de hepatitis C. El objetivo de este estudio fue medir la asociación entre el antecedente transfusional antes de 1994 e infección por virus de hepatitis C en mujeres atendidas en la zona metropolitana de Guadalajara, México. MÉTODOS Estudio observacional, analítico, de casos y controles, en el que se incluyeron mujeres sanas y mujeres con infección por hepatitis vírica tipo C, en las cuales se determinó el antecedente transfusional antes y después de 1994. El grupo de casos lo conforman 150 mujeres con diagnóstico serológico y confirmatorio de hepatitis C, en tanto el grupo control son 150 mujeres sanas con serología negativa. RESULTADOS Se encontró un odds ratio de 9,07 (intervalo de confianza 95% 5,37 ­ 15,3; p<0,001), una proporción de casos expuestos de 0,72, de controles expuestos de 0,22, una fracción atribuible poblacional de 0,64 (intervalo de confianza 0,53 ­ 0,73) y una fracción atribuible en expuestos de 0,88 (intervalo de confianza 0,81 ­ 0,93). CONCLUSIONES En las mujeres, el haber tenido una transfusión antes de 1994 en la zona metropolitana de Guadalajara, representa un riesgo 9,07 veces mayor de infección por virus de la hepatitis C que no tener antecedente transfusional en esa fecha.

INTRODUCTION Most blood transfusions occur in female patients. The introduction of serologic screening practices by blood banks reduced the transfusion-related rate of infection with hepatitis C virus (HCV). In Mexico patients with pre-1994 transfusion history are at high risk of being detected with HCV infection. We aimed at establishing an interrelationship between two variables: pre-1994 transfusion history and rate of infection in women treated in the Guadalajara Metropolitan Area hospitals, in Mexico. METHODS Analytical observational case-control study which included both non-infected women and patients diagnosed with hepatitis C virus infection, in whom the pre-1994 transfusion history was determined. The cases were 150 women with confirmed hepatitis C virus serologic diagnosis. The controls were 150 women whose hepatitis C virus-detection serologic tests had yielded negative results. RESULTS An odds ratio of 9.07 (95% CI: 5.37 ­ 15.3; p< 0.001) was found where the rate of infection for the case group was 0.72 while the control group had a ratio of 0.22; population attributable risk (PAR) was 0.64 (95% CI: 0.53 ­ 0.73), while etiologic fraction was 0.88 (95% CI: 0.81 ­ 0.93). CONCLUSIONS Among women, having been exposed to pre-1994 blood transfusion means a risk 9.07 times higher than not being exposed to blood transfusion in the same time frame.

Ant predation on herbivores through a multitrophic lens: how effects of ants on plant herbivore defense and natural enemies vary along temperature gradients.

Ants are keystone predators in terrestrial trophic cascades. Addressing ants' roles in multitrophic interactions across regional gradients is important for understanding mechanisms behind range limits of species. We present four hypotheses of trophic dynamics occurring when ants are rare: first, there is a shift in predator communities; second, plants decrease investments in ant attraction and increase production of secondary metabolites; third, lower herbivory at high elevations allows plants to tolerate herbivory; and fourth, distribution of ant-plants can be limited based on ant abundance. Conducting experiments on multitrophic effects of ants across elevational gradients, and incorporating these results to ecological niche modeling (ENM) will improve our knowledge of the impacts of global change on ants, trophic interactions, and biodiversity.

Hookah smoking behavior initiation in the context of Millennials.

OBJECTIVES: This study aims to examine current hookah users' perceptions, attitudes, and normative beliefs regarding hookah smoking to further elucidate the rise in hookah smoking prevalence among young adults (aged 18-24 years) and reveal why hookah smoking is perceived as less harmful than other forms of tobacco consumption. STUDY DESIGN: Qualitative. METHODS: Data from six focus group interviews with hookah smokers aged between 18 and 24 years were analyzed using a grounded theory approach. Focus groups were evenly split between frequent and infrequent hookah users, and were predominantly composed of college students, with two groups of hookah users consisting of 18-24 year olds of non-student status. RESULTS: Hookah users shared a much larger set of positive hookah smoking behavioral beliefs as opposed to negative behavioral beliefs. Generational traits served as the overarching commonality among the behavior performance initiation determinants observed. The most notable generational trends observed were within the cultural category, which included the following millennial characteristics: autonomy, personalization, novelty appeal, convenience, globally oriented, entertainment, collaboration, health conscious, and valuing their social network. CONCLUSIONS: Millennial hookah users revealed mindfulness regarding both potential negative and positive reasons stemming from continued hookah use; however, behavioral beliefs were primarily fixated on the perception that hookah smoking was a healthier alternative to cigarette smoking. Future implications for this study's findings include generating more positive ways to express these traits for young adults; policy implications include raising hookah bar age limits, implementing indoor smoking restrictions, and limiting the ease of accessibility for purchasing hookah supplies.

Review on technological and scientific aspects of feruloyl esterases: A versatile enzyme for biorefining of biomass.

With increasing focus on sustainable energy, bio-refining from lignocellulosic biomass has become a thrust area of research. With most of the works being focused on biofuels, significant efforts are also being directed towards other value added products. Feruloyl esterases (EC. 3.1.1.73) can be used as a tool for bio-refining of lignocellulosic material for the recovery and purification of ferulic acid and related hydroxycinnamic acids ubiquitously found in the plant cell wall. More and more genes coding for feruloyl esterases have been mined out from various sources to allow efficient enzymatic release of ferulic acid and allied hydroxycinnamic acids (HCAs) from plant-based biomass. A sum up on enzymatic extraction of HCAs and its recovery from less explored agro residual by-products is still a missing link and this review brushes up the achieved landmarks so far in this direction and also covers a detailed patent search on this biomass refining enzyme.

Rapid mineralisation of the Organic Fraction of Municipal Solid Waste.

The effect of pH, C/N ratio, addition of a microbial consortium (MC) and temperature upon mineralisation of Organic Fraction of Municipal Solid Waste (OFMSW) was studied; mineralisation was measured through the CO2 production rate and total CO2 formation. Through this process up to 432.9mg of CO2g(-1) initial dry matter (IDM) after 2days of treatment was obtained. It was found that under a slightly acidic pH (5-6) and C/N of 30, the mineralisation process was accelerated. Moreover, temperature (27-50°C) had no effect on the total CO2 produced. The highest CO2 production rate (5.28d(-1)) was observed at 27°C, C/N ratio of 30 and 8% of microbial consortium; it is at least 3.52 times higher than that reported (1.5d(-1)). The highest release of reducing sugars was determined at 50°C, possibly due to an increase in hydrolytic enzymes. Results suggest the potential use of rapid mineralisation of OFMSW for further friendly environmental processes.

Rapid determination of letrozole, citalopram and their metabolites by high performance liquid chromatography-fluorescence detection in urine: Method validation and application to real samples.

This work reports the validation of a high precision and accuracy method for the simultaneous determination of letrozole, citalopram and their metabolites in urine by high performance liquid chromatography with fluorescence detection. Dilution (urine:mobile phase, 1:2, v/v) was the only sample preparation step. The separation was carried out in a Kromasil C(18) (150mm×4.6mm) column, and the mobile phase was phosphate buffer 80mM (pH 3.0) and acetonitrile (65:35, v/v) at a flow rate of 1.0mL/min. The analytes were detected at 295nm after excitation at 230nm. Linearity was observed in the range of 1.0-1000ng/mL for letrozole and its metabolite and 2.5-1000ng/mL for citalopram and their metabolites, with limits of detection and quantification between 0.09-1.0 and 0.27-1.65ng/mL, respectively. The precisions were satisfactory with RSDs between 0.17 and 5.71%. The accuracy was studied by spiking three urines from healthy female volunteers, and the recoveries were from 85 to 103%. The method was applied to urine samples from women under treatment for breast cancer and depression diseases.

Direct and fast determination of paclitaxel, morphine and codeine in urine by micellar electrokinetic chromatography.

A micellar electrokinetic chromatography (MEKC) method was developed for the determination of paclitaxel, morphine and codeine in human urine from patients under cancer treatment. The background electrolyte consisted of a borate buffer (pH 9.2; 20 mM) with sodium dodecyl sulfate (60 mM) and 5% MeOH. The applied voltage was 25 kV, temperature was 20 °C and the sample injection was performed in the hydrodynamic mode. All analyses were carried out in a fused silica capillary with an internal diameter of 75 µm and a total length of 57 cm. The detection of target compounds was performed at 212 nm. Under these conditions, a complete separation of paclitaxel, morphine and codeine was achieved in less than 15 min. According to the validation study, the developed method was proved to be accurate, precise, sensitive, specific, rugged and robust. This method was applied to the analysis of six urines samples from different cancer patients undergoing treatment with paclitaxel or/and codeine. In all the urine paclitaxel determination were done.

Host conservatism, host shifts and diversification across three trophic levels in two Neotropical forests.

Host-parasite systems have been models for understanding the connection between shifts in resource use and diversification. Despite theoretical expectations, ambiguity remains regarding the frequency and importance of host switches as drivers of speciation in herbivorous insects and their parasitoids. We examine phylogenetic patterns with multiple genetic markers across three trophic levels using a diverse lineage of geometrid moths (Eois), specialist braconid parasitoids (Parapanteles) and plants in the genus Piper. Host-parasite associations are mapped onto phylogenies, and levels of cospeciation are assessed. We find nonrandom patterns of host use within both the moth and wasp phylogenies. The moth-plant associations in particular are characterized by small radiations of moths associated with unique host plants in the same geographic area (i.e. closely related moths using the same host plant species). We suggest a model of diversification that emphasizes an interplay of factors including host shifts, vicariance and adaptation to intraspecific variation within hosts.

Voltammetric determination of Imatinib (Gleevec) and its main metabolite using square-wave and adsorptive stripping square-wave techniques in urine samples.

The voltammetric behaviour of Imatinib (STI 571) and its main metabolite (N-demethylated piperazine derivative) were studied by square-wave techniques, resulting in to two methods for their determination in aqueous and urine samples at pH 2. The application of the square-wave (SW) without the adsorptive accumulation and voltammetric stripping (AdSV) exhibit a peak at a reduction potential of -0.70V for an accumulation potential of -0.45V. The sensitivity was higher for the stripping technique because a signal four times higher than that provided by the square-wave method without the previous accumulation was obtained. Due to the fact that Imatinib and its metabolite show the same voltammetric reduction process, some experiments were performed in order to compare the voltammetric response of Imatinib and its main metabolite in a similar ratio than that of the therapeutic concentration. The calibration curve for Imatinib in urine was linear in the range from 1.9x10(-8) to 1.9x10(-6)M in stripping mode with an accumulation time (t(acc)) of 10s. The relative standard deviations obtained for concentration levels of Imatinib as low as 2.0x10(-7)M for square-wave was 2.17% (n=9) and for stripping square-wave was 2.65% (n=9) in the same day. The limits of detection for square-wave and stripping square-wave were 5.55x10(-9) and 5.19x10(-9)M, respectively. Thus, the presented method are straightforward, rapid and sensitive and has been applied to the determination of Imatinib and its main metabolite altogether in urine samples from real patients.