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Pseudomonas aeruginosa is the main bacterial model to study cooperative behaviors, since it yields exoproducts such as exoproteases and siderophores that act as public goods and can be exploited by selfish non-producers that behave as social cheaters. Non-producers of the siderophore pyoverdine are typically isolated in media with low free iron, mainly casamino acids medium supplemented with transferrin. Nevertheless, using a protein as the iron chelator could additionally select mutants unable to produce exoproteases that degrade the transferrin to facilitate iron release. Here, we investigated the dynamics of pyoverdine and exoprotease production in media in which iron was limited by using either transferrin or a cation chelating resin. Our experiments show that concomitant loss of pyoverdine and exoprotease production readily develops in media with transferrin whereas only lack of pyoverdine emerges in medium treated with the resin. Genomic characterization of the exoprotease- and pyoverdine-less mutants revealed large deletions (13 to 33 Kb) including Quorum Sensing (lasR, rsal and lasl) and flagellar genes. Complementation experiments, PCR and motility tests confirmed the deletions. Our work shows that using transferrin as an iron chelator imposes simultaneous selective pressure for the loss of pyoverdine and exoprotease production. The unintended effect of transferrin observed in our experiment settings can help revisiting or informing the design of similar studies.

9 páginas, 4 figuras, 1 tabla., Background: Molecular diagnostics are considered the most promising route to achieving rapid, universal drug susceptibility testing for Mycobacterium tuberculosiscomplex (MTBC). We aimed to generate a WHO endorsed catalogue of mutations to serve as a global standard for interpreting molecular information for drug resistance prediction. Methods: A candidate gene approach was used to identify mutations as associated with resistance, or consistent with susceptibility, for 13 WHO endorsed anti-tuberculosis drugs. 38,215 MTBC isolates with paired whole-genome sequencing and phenotypic drug susceptibility testing data were amassed from 45 countries. For each mutation, a contingency table of binary phenotypes and presence or absence of the mutation computed positive predictive value, and Fisher's exact tests generated odds ratios and Benjamini-Hochberg corrected p-values. Mutations were graded as Associated with Resistance if present in at least 5 isolates, if the odds ratio was >1 with a statistically significant corrected p-value, and if the lower bound of the 95% confidence interval on the positive predictive value for phenotypic resistance was >25%. A series of expert rules were applied for final confidence grading of each mutation. Findings: 15,667 associations were computed for 13,211 unique mutations linked to one or more drugs. 1,149/15,667 (7·3%) mutations were classified as associated with phenotypic resistance and 107/15,667 (0·7%) were deemed consistent with susceptibility. For rifampicin, isoniazid, ethambutol, fluoroquinolones, and streptomycin, the mutations' pooled sensitivity was >80%. Specificity was over 95% for all drugs except ethionamide (91·4%), moxifloxacin (91·6%) and ethambutol (93·3%). Only two resistance mutations were classified for bedaquiline, delamanid, clofazimine, and linezolid as prevalence of phenotypic resistance was low for these drugs. Interpretation: This first WHO endorsed catalogue of molecular targets for MTBC drug susceptibility testing provides a global standard for resistance interpretation. Its existence should encourage the implementation of molecular diagnostics by National Tuberculosis Programmes. Funding: UNITAID, Wellcome, MRC, BMGF., Unitaid, Wellcome Trust, UK Medical Research Council, and Bill and Melinda Gates Foundation

Background We determined the frequency of genetic polymorphisms in three anti‐TB drug metabolic proteins previously reported: N‐acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), and arylacetamide deacetylase (AADAC) within a Peruvian population in a cohort of TB patients. Methods We genotyped SNPs rs1041983, rs1801280, rs1799929, rs1799930, rs1208, and rs1799931 for NAT2; rs3813867 and rs2031920 for CYP2E1; and rs1803155 for AADAC in 395 participants completed their antituberculosis treatment. Results Seventy‐four percent of the participants are carriers of slow metabolizer genotypes: NAT2*5, NAT2*6, and NAT2*7, which increase the sensitivity of INH at low doses and increase the risk of drug‐induced liver injuries. Sixty‐four percent are homozygous for the wild‐type CYP2E1*1A allele, which could increase the risk of hepatotoxicity. However, 16% had a NAT2 fast metabolizer phenotype which could increase the risk of acquiring resistance to INH, thereby increasing the risk of multidrug‐resistant (MDR) or treatment failure. The frequency of rs1803155 (AADAC*2 allele) was higher (99.9%) in Peruvians than in European American, African American, Japanese, and Korean populations. Conclusions This high prevalence of slow metabolizers for isoniazid in the Peruvian population should be further studied and considered to help individualize drug regimens, especially in countries with a great genetic diversity like Peru. These data will help the Peruvian National Tuberculosis Control Program develop new strategies for therapies., High prevalence of slow metabolizers for isoniazid in the Peruvian population should be further studied and considered to help individualize drug regimens, especially in countries with a great genetic diversity like Peru.

Cape gooseberry production has been limited by vascular wilt caused by Fusarium oxysporum f. sp. physali (Foph). Fusaric acid (FA) is a mycotoxin produced by many Fusarium species such as F. oxysporum formae speciales. The effects of the interaction between this mycotoxin and plants (such as cape gooseberry) under biotic stress (water deficit, WD) have been little explored. Three experiments were carried out. The objectives of this study were to evaluate (i) different Foph inoculum densities (1 × 104 and 1 × 106 conidia ml−1; experiment (1); (ii) the effect of times of exposure (0, 6, 9, and 12 h) and FA concentrations (0, 12.5, 25, 50, and 100 mg L−1; experiment (2), and (iii) the interaction between Foph (1 × 104 conidia mL−1) or FA (25 mg L−1 × 9 h), and WD conditions (experiment 3) on the physiological (plant growth, leaf stomatal conductance (gs), and photochemical efficiency of PSII (Fv/Fm ratio) and biochemical [malondialdehyde (MDA) and proline] responses of cape gooseberry seedling ecotype Colombia. The first experiment showed that Foph inoculum density of 1 × 106 conidia ml−1 caused the highest incidence of the disease (100%). In the second experiment, gs (~40.6 mmol m−2 s−1) and Fv/Fm ratio (~0.59) decreased, whereas MDA (~9.8 μmol g−1 FW) increased in plants with exposure times of 9 and 12 h and an FA concentration of 100 mg L−1 compared with plants without FA exposure or concentrations (169.8 mmol m−2 s−1, 0.8, and 7.2 μmol g−1 FW for gs, Fv/Fm ratio and MDA, respectively). In the last experiment, the interaction between Foph or FA and WD promoted a higher area under the disease progress curve (AUDPC) (Foph × WD = 44.5 and FA × WD = 37) and lower gs (Foph × WD = 6.2 mmol m−2 s−1 and FA × WD = 9.5 mmol m−2 s−1) compared with plants without any interaction. This research could be considered as a new approach for the rapid scanning of responses to the effects of FA, Foph, and WD stress not only on cape gooseberry plants but also on other species from the Solanaceae family.

Biochar has been used as an amendment for disturbed soils. However, the changes of the rhizobacterial community after the biochar addition in mine soils, has not yet been elucidated. The aim of this study was to evaluate the response in the rhizobacterial communities of Brachiaria decumbens during different reclamation processes of coal mining using biochar. Five treatments were carried out: control, mine soil + biochar, mine soil + biochar + Azospirillum brasilense, mine soil + biochar + arbuscular mycorrhizal fungal + Mortierella sp. DNA from the rhizospheric soil was sequenced by Ion Torrent. The relative abundance in each sample was calculated. The Proteobacteria (70%) and Actinobacteria (23%) phyla dominated the rhizobacterial community composition during the establishment time. Seven months after seeding, Actinobacteria decreased significantly, while Proteobacteria increased. The Acidobacteria phylum was higher in the control. There was a higher abundance of Proteobacteria with the biochar treatments than for the control, thus the baseline for the rhizobacterial community changes induced by biochar was provided. The alpha diversity index showed the effect of biochar on the diversity and dominance of the rhizobacterial communities. The hierarchical clustering tree showed a correlation between the treatments with biochar, and a significant differentiation between these and the control treatment.

Mexico is the fifth largest producer of fresh oranges in the world, and Tepalcingo in Morelos has recently become an important area of cultivation for cv Valencia. The objectives of this work were to assess fruit quality in the oranges from this region, and to determine their commercial life during storage. Significant differences occurred in the juice volume of fruits during all three seasons evaluated; however, no differences were detected in their weight, size, shape, rind thickness, or flavedo color (L*, C*, h). TSS/TA (total soluble solids/titratable acidity) ratios were high (10.3-12.9) in fruits collected during spring and summer. Overall, the oranges met the specifications of both national and international quality standards. Changes during storage indicated that compression force, % weight loss, and sensorial flavor were negatively impacted by storage at 24⁰C while TSS and TA of juice remained unaffected at 11 and 24 ⁰C. The commercial life of oranges was 21 d at 24 ⁰C and > 28 d at 11 ⁰C as determined from changes in the concentrations of certain aroma compounds and from differences in the firmness of their rinds. Such changes correlate well with both weight loss and the sensorial perception of quality attributes.

Sphingobium yanoikuyae S72 was isolated from the rhizosphere of sorghum plant, Mexico. Its role on the degradation of polycyclic aromatic hydrocarbon (PAH) was evaluated in a minimal medium containing one of biphenyl, naphthalene, phenanthrene, xylene and Toluene as the only carbon source. It grew effectively in each minimal medium (Bushnell Haas, BH). Gas column chromatography–mass spectrometry (GC-MS) analysis on the metabolite recovered after S72’s growth in BH showed that it successfully degraded the PAHs tested resulting in the degradation of biphenyl (85%), phenanthrene (93%), naphthalene (81%), xylene (19%) and toluene (30%). The complete genome of the S72 was sequenced to evaluate the genetic bases of S72`s degradation of PAH. The genome was assembled de novo and reduced to 1 contig and consists of 5,532,623 bp, 5005 protein-coding genes. The analysis of the COG categories in S72 in comparison with other Sphingobium yanoikuyae and other PAH degrading gene, showed that it has in higher abundance in some categories that have been associated with the degradation of PAH (energy production and conversion (COG C, 6.35), carbohydrate transport and metabolism (COG G, 6.20%), lipid transport and metabolism (COG I, 6.99), secondary metabolites biosynthesis (COG Q, 4.52%), general function prediction only in transport and catabolism (COG R, 9.93),) Pan-core genome analysis revealed that about 126 unique genes in S72 are associated with the degradation of xenobiotics and PAHs. Most gene found in S72 are associated with the peripheral degradation pathway for PAH. Based on our observation we proposed a possible benzoate degradation pathway.

The development of novel bioremediation strategies has focused on the isolation and identification of microorganisms that can thrive in polluted environments to evaluate their potential as biotechnological tools in bioremediation techniques. In this work, a bacterium isolated from hydrocarbon-contaminated soils from the Burgos basin was identified and its hydrocarbon degradation potential was evaluated. Identification based on sequencing the 16S rRNA gene identified one of the isolates (R3) as Microbacterium petrolearium. This strain was mainly antibiotic-sensitive with elevated carbohydrate assimilation differing from previously reported strains. Moderate surfactant production (I24 = 22.97 %) was observed, which was absent in a cell-free extract. M. petrolearium R3 showed increased growth that correlated with pollutant concentration. For light crude oil, at a higher contaminant percentage, the R3 strain showed increased growth; however, in the case of diesel, no growth was detected. The aforementioned data indicate that M. petrolearium strain R3, isolated from local sources, has potential use as a tool for hydrocarbon-contaminated soil bioremediation.

Background Drug susceptibility testing (DST) patterns of Mycobacterium tuberculosis (MTB) from patients with rifampicin-resistant tuberculosis (RR-TB) or multidrug-resistant TB (MDR-TB; or resistant to rifampicin and isoniazid (INH)), are important to guide preventive therapy for their household contacts (HHCs). Methods As part of a feasibility study done in preparation for an MDR-TB preventive therapy trial in HHCs, smear, Xpert MTB/RIF, Hain MTBDRplus, culture and DST results of index MDR-TB patients were obtained from routine TB programs. A sputum sample was collected at study entry and evaluated by the same tests. Not all tests were performed on all specimens due to variations in test availability. Results Three hundred eight adults with reported RR/MDR-TB were enrolled from 16 participating sites in 8 countries. Their median age was 36 years, and 36% were HIV-infected. Routine testing on all 308 were confirmed as having RR-TB, but only 75% were documented as having MDR-TB. The majority of those not classified as having MDR-TB were because only rifampicin resistance was tested. At study entry (median 59 days after MDR-TB treatment initiation), 280 participants (91%) were able to produce sputum for the study, of whom 147 (53%) still had detectable MTB. All but 2 of these 147 had rifampicin DST done, with resistance detected in 89%. Almost half (47%) of the 147 specimens had INH DST done, with 83% resistance. Therefore, 20% of the 280 study specimens had MDR-TB confirmed. Overall, DST for second-line drugs were available in only 35% of the 308 routine specimens and 15% of 280 study specimens. Conclusions RR-TB was detected in all routine specimens but only 75% had documented MDR-TB, illustrating the need for expanded DST beyond Xpert MTB/RIF to target preventive therapy for HHC.

Antioxidants, antioxidant capacity, and the expression of isoprenoid metabolism–related genes and two pigmentation-related transcription factors were studied in four native and four hybrid tomato (Solanum lycopersicum) genotypes with different-colored fruit. Red fruit genotypes were associated with greater lycopene, β-carotene, lipophilic antioxidant capacity, and greater chromoplast-specific lycopene β-cyclase (CYC-B) transcript levels. Orange fruit genotypes had greater concentrations of tocopherols and greater transcript levels of homogentisate phytyl transferase (VTE-2), 1-deoxy-D-xylulose phosphate synthase (DXS), and 4-hydroxyphenylpyruvate dioxygenase (HPPD). The yellow fruit genotype was greater in total polyphenol and hydrophilic antioxidant capacity with greater expression of geranylgeranyl reductase (GGDR), phytol kinase (VTE-5), phytoene synthase (PSY) 2, lycopene β-cyclase (LCY-B), SlNAC1, and SINAC4. Greater levels of individual antioxidants were associated with specific coloration of tomato fruit. Moreover, the negative correlations between the expression of PSY1 and VTE-5, and between lycopene and chlorophyll, suggest a balance between carotenoids, tocopherols, and chlorophylls. The results of this study support either the direct commercialization of tomatoes with different color fruit or use of their genotypes in breeding programs to increase antioxidant levels among existing cultivars.

The tomato (Solanum lycopersicum L.) fruit has been widely studied because of its high consumption, nutritional value, and well-characterized genome. It also represents a good model for studying the structure and function of the cuticle, a protective film that is deposited on the surface of outer epidermal cell walls, and affects the integrity and firmness of the fruit, and, therefore, its commercialization. To evaluate the differences in their structure and function, we characterized the morphology of the cuticle and the epidermis and their relationship to firmness, brightness, weight loss, and transcript levels of polygalacturonase (PGA) in four hybrid genotypes and four native genotypes of different origins, shapes, and colors. Our results show a different architecture of the epidermis and cell wall among the genotypes. Native genotypes showed irregular-shaped epidermal cells and a thicker epidermis. Anticlinal pegs were also present to only one-third of the depth of the epidermal cells. The hybrid fruit surface was smoother compared to native genotypes, and it was associated with a higher level of brightness and a less weight loss. A negative correlation between firmness and PGA transcript levels was found. The chartreuse yellow genotype was the firmest, and it had the lowest levels of PGA expression. Meanwhile, the black genotype displayed the lowest weight loss and stem scar diameter. Our results suggest that several morphological features of the cuticle and epidermis have been modified through selection of the tomato fruit, altering quality parameters, such as weight loss and firmness.

Spondias purpurea L. is a fruit native to Mexico, however, it is found as far away as Brazil. It possesses a high commercial potential owing to its sensorial and nutritional qualities and its low cost of production. There exists a variety of ecotypes that have not been characterized and their adequate selection process, according to their strongest functional characteristics, will allow the establishment of improvement programs for this genetic resource. The object of this study was the chemical characterization and the determination of the in vitro and in vivo antioxidant capacity of 7 Spondias purpurea L. ecotypes. Differences were observed in the antioxidant capacity and the content of functional compounds among all the ecotypes analyzed. A high total phenolic content and a low flavonoid and carotenoid content were found, both in the epicarp and in the pulp. In each ecotype, the hydrophilic phase presented up to 40 times greater antioxidant capacity compared to the lipophilic phase. The hydrophilic phase of the epicarp of "Costena Tierra Colorada" had the greatest antioxidant capacity and highest total phenolic content, whereas "Jocote" presented the lowest antioxidant capacity and total phenolic content. A positive correlation was observed between phenol levels and the antioxidant capacity in the epicarp. Regarding antioxidant activity in vivo, it was observed that in all analyzed concentrations of hydrophilic extracts of the epicarp of "Costena Tierra Colorada" and in the highest "Jocote" concentrations, they provided thermo-protection against heat stress as well as a general well-being to the worm as evidenced by their high mobility.

This chapter will refresh your knowledge about certain concepts that will be useful throughout the rest of the book. First, you will learn about common robotic components employed with the autopilot, such as spatial pose, getter and setter concepts, variables, functions, modules, objects, coding and installation differences, and computational efficiency. Concerning the ArduPilot libraries, you will learn the usual parts of ArduPilot code and the archetypes of programming.

Triosephosphate isomerase (TPI) is a glycolysis enzyme, which catalyzes the reversible isomerization between dihydroxyactetone-3-phosphate (DHAP) and glyceraldehyde-3-phosphate (GAP). In pathogenic organisms, TPI is essential to obtain the energy used to survive and infect. Fusarium oxisporum (Fox) is a fungus of biotechnological importance due to its pathogenicity in different organisms, that is why the relevance of also biochemically analyzing its TPI, being the first report of its kind in a Fusarium. Moreover, the kinetic characteristics or structural determinants related to its function remain unknown. Here, the Tpi gene from F. oxysporum was isolated, cloned, and overexpressed. The recombinant protein named FoxTPI was purified (97% purity) showing a molecular mass of 27 kDa, with optimal activity at pH 8.0 and and temperature of 37 &deg, C. The values obtained for Km and Vmax using the substrate GAP were 0.47 &plusmn, 0.1 mM, and 5331 &mu, mol min&minus, 1 mg&minus, 1, respectively. Furthemore, a protein structural modeling showed that FoxTPI has the classical topology of TPIs conserved in other organisms, including the catalytic residues conserved in the active site (Lys12, His94 and Glu164). Finally, when FoxTPI was analyzed with inhibitors, it was found that one of them inhibits its activity, which gives us the perspective of future studies and its potential use against this pathogen.

Manganese Enhanced MRI (MEMRI) utilizing different manganese chloride (MnCl2) delivery methods, has yielded valuable architectural, functional and connection information about the brain. MEMRI also has the potential in characterizing neural pathways in the spinal cord. The spinal cord grey matter is anatomically composed of nine distinct cellular laminae, where each of the laminae receives input from a specific type of neuronal population and process or serves as a relay region in a specific sensory or motor pathway. This type of laminar arrangement in the spinal cord is currently only visualized by histological methods. It is of significant interest to determine whether laminar specific enhancement by Mn2+ can be achieved in the spinal cord, as has been reported in the brain and olfactory pathway. Here we focus on using MEMRI to determine the specific laminae of the thoracic region of the spinal cord. We focus on MnCl2 changes in the ascending and descending tracts of the spinal cord. Major factors in applying this technique in the spinal cord are the ability to acquire high-resolution spinal cord images and to determine a noninvasive route of administration which will result in uptake by the central nervous system.We have applied the MEMRI approach by intraperitoneal (i.p). delivery of MnCl2 and imaged lumbar and thoracic spinal cord levels in rats to determine whether T1 weighted MRI can detect spinal cord laminae 48 hours following MnCl2 administration. T1 weighted images of the lower lumbar level were obtained from MnCl2 injected and control rats. Here we demonstrate laminar specific signal enhancement in the spinal cord of rats administered with MnCl2 vs. controls in MRI of the cord with ultra-high, 69 μm in-plane resolution. We also report reduced T1 values over time in MnCl2 groups across laminae I-IX. The regions with the largest T1 enhancements were observed to correspond to laminae that contain either high cell density or large motor neurons, making MEMRI an excellent tool for studying spinal cord architecture, physiology and function in different animal models.

La presencia de la lagartija Coleonyx elegans fue sugerida recientemente para Hidalgo, sin embargo, se carecía de información suficiente que ratificara su presencia en el estado. En este trabajo presentamos los primeros registros confirmados para el estado, los cuales se encontraron en ambientes antropizados de la Huasteca hidalguense, en los municipios de Jaltocán y Huejutla de Reyes.

Context: Echinacea (Asteraceae) is used because of its pharmacological properties. However, there are few studies that integrate phytochemical analyses with pharmacological effects. Objective: Evaluate the chemical profile and biological activity of hydroalcoholic Echinacea extracts. Materials and methods: Density, dry matter, phenols (Folin–Ciocalteu method), flavonoids (AlCl3 method), alkylamides (GC-MS analysis), antioxidant capacity (DPPH and ABTS methods), antiproliferative effect (SRB assay), anti-inflammatory effect (paw oedema assay, 11 days/Wistar rats; 0.4 mL/kg) and hypoglycaemic effect (33 days/Wistar rats; 0.4 mL/kg) were determined in three Echinacea extracts which were labelled as A, B and C (A, roots of Echinacea purpurea L. Moench; B, roots, leaves, flowers and seeds of Echinacea purpurea; C, aerial parts and roots of Echinacea purpurea and roots of Echinacea angustifolia DC). Results: Extract C showed higher density (0.97 g/mL), dry matter (0.23 g/mL), phenols (137.5 ± 2.3 mEAG/mL), flavonoids (0.62 ± 0.02 mEQ/mL), and caffeic acid (0.048 mg/L) compared to A and B. A, B presented 11 alkylamides, whereas C presented those 11 and three more. B decreased the oedema (40%) on day 2 similar to indomethacin. A and C showed hypoglycaemic activity similar to glibenclamide. Antiproliferative effect was only detected for C (IC50 270 μg/mL; 8171 μg/mL; 9338 μg/mL in HeLa, MCF-7, HCT-15, respectively). Discussion and conclusion: The difference in the chemical and pharmacological properties among extracts highlights the need to consider strategies and policies for standardization of commercial herbal extracts in order to guarantee the safety and identity of this type of products.

With the aim to explore the diversity of aquatic fungi in Mexico we present an investigation using a fragment of the 18S ribosomal DNA as a molecular marker obtained from different water bodies (marine, brackish and fresh water). Ribosomal gene fragments were obtained by DNA amplification, the resulting sequences were compared using multiple alignments against a collection of classified reference fungal sequences and then subjected to phylogenetic clustering allowing the identification and classification of DNA sequences from environmental isolates as fungal down to the family level, provided enough reference sequence were available. From our ensemble of 2,020 sequences identified as fungal, 23.8% were classified at the family level, 48.5% at the order level, 13% at the class/subphylum level and 14.7% of the sequences (all from the same site) could not be unambiguously positioned in any of our reference fungal groups but were closely related to uncultivated marine fungi. The most frequently recovered phylum was Ascomycota (89.1%), followed by Chytridiomycota (8.1%), Basidiomycota (2.8%) and Mucoromycotina (1.3%).

Response surface methodology was applied in order to select the optimal thermal treatment (TT) and modified atmosphere packaging (MAP) needed to preserve minimally processed cactus stems, cv Atlixco. Accordingly, a 42 s/48°C TT together with a 10% CO2 MAP were selected, and their effects evaluated during storage at 4°C. Controls lost more weight (3.8%) than TT (3.3%), MAP (1.4%), and TT-MAP (1.3%) cactus stems. Chilling injury (CI) symptoms decreased and were of a similar magnitude in both MAP and TT-MAP cactus stems, whereas TT-MAP cladodes were better able to preserve their characteristic green color and freshness, even after 28 days. Biochemically, no differences were detected in the electrolyte leakage (EL) of cactus stems, regardless of treatment. However, the high levels of adenosine triphosphate and of the reduced form of ascorbic acid, especially in MAP and TT-MAP cladodes, suggest that an efficient antioxidant system was present in their tissues throughout storage. PRACTICAL APPLICATIONS: In Mexico, cactus stems have been eaten as vegetables since pre-Hispanic times, and their current status as functional foods has helped them spread to various other countries. As cactus stems possess abundant spines, minimal processing is necessary in order to remove them. Stems must also be kept at 4°C so that their quality and general safety as food items are adequately preserved. However, we previously found that this temperature caused significant CI after just 14 days of storage. The present study, therefore, describes the selection of optimal conditions for the application of a TT that, together with a modified atmosphere (MA), induce tolerance to CI and maintain the quality of stems for up to 28 days. As a result, this work provides the necessary postharvest tools to further expand the distribution and sale of minimally processed cactus stems into domestic and international markets.

Tropical fruit peels are generally discarded as waste, yet they contain bioactive substances that could have various uses; in addition, their pharmacological potential remains unexplored. This study aims to characterize the phytochemical profile, toxicity, and pharmacological potential of methanol extracts obtained from the peels of the following tropical fruit species: Annona squamosa L. (purple sugar apple), Annona reticulata L. (custard apple), Chrysophyllum cainito L. (green star apple), and Melicoccus bijugatus Jacq. (mamoncillo). Methanol peel extracts were obtained by maceration. All extracts contained flavonoids, anthraquinones, and triterpenoids as determined by colorimetric methods. A. squamosa and C. cainito exhibited the highest content of total phenols as assayed by the Folin-Ciocalteu method. M. bijugatus showed the highest content of total sugars (fructose, glucose, and sucrose) as determined by high-performance liquid chromatography. A. squamosa and C. cainito presented the highest antioxidant capacities (according to 2,2'-diphenyl-1-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid, and cupric reducing antioxidant capacity assays), displayed moderate toxicity against HCT-116 cells, and increased the vinblastine susceptibility of MCF-7/Vin+. A. squamosa and M. bijugatus extracts demonstrated modulation of acetylcholinesterase activity, whereas those of A. reticulata showed anti-inflammatory activity by inhibiting protein denaturation. These results confirm that tropical fruit peels can be valuable sources of bioactive compounds, and our findings provide new information about their pharmacologic potential so that they can be used as raw material for the development of new drugs aimed at treating a variety of ailments.

Currently it is well known that yeasts play an essential role in the production of different beverages. In this paper, were identified some of the yeasts involved in the fermentation process of the pulque, a Mexican traditional beverage. Samples were collected from different regions of Mexico and yeasts were detected directly from samples without cultivation. Identifying the yeasts was obtained using amplification the D1/D2 domain of the 26S rRNA gene and Denaturing Gradient Gel Electrophoresis (DGGE). The results of DGGE showed different profiles of bands in each of the analyzed samples, indicating the presence of several species of yeast, which was also confirmed by sequencing of the bands corresponding to the domain D1/D2, succeeded in identifying five species of yeasts. The results obtained in this work demonstrated that the technique used for identification of yeasts of pulque was efficient. Besides, the optimization of this method could also allow rapid identification of yeasts and help understand the role of these in the fermentation process of this beverage, as well as the isolation of strains of interest for biotechnological purposes such as production of ethanol or metabolites with nutraceutical activity.

We describe a new species of Plestiodon in the P. brevirostris group from the Balsas Basin in central Mexico. It is distinguished from the other species in the group by the following combination of traits: supraoculars four; interparietal enclosed posteriorly by parietals; primary temporal present; seventh supralabial usually contacting upper secondary temporal; longitudinal dorsal scale rows around midbody 23–26; Toe-IV lamellae 13–15; limbs not overlapping when adpressed against body; dorsolateral light line extending posteriorly to level of posterior end of anterior fourth of body or beyond; light median line absent in all growth stages; primary lateral dark lines separated medially by six dorsal scale rows and upper half of adjacent row on each side at level of midbody; lower secondary dark line faint at level of neck; and light coloration of supralabials extending ventrally to lip border. Analyses based on DNA sequences of three loci support the distinctiveness of the new species, as well as its sister species relationship with P. ochoterenae. The Environmental Vulnerability Score of the new species places it in the high vulnerability category.

Commercialization of agricultural products, including seeds and its derived products, represents an important economic source for developing countries. Natural colorants obtained from the seeds of achiote plant (annatto) have been used since pre-Hispanic times. Also, production of this crop has been important for Mayan cuisine. Annual world production of achiote seeds is approximately 14,500 tons (dry weight). Two thirds of the production is commercialized as dried seeds and the rest as colorant. Latin America produces 60% of the total world production, followed by Africa (27%) and Asia (12%). The main producers in Latin America are Peru, Brazil and Mexico. The purpose of the present paper is to review the most recent literature on Bixa orellana L. focusing on bixin, norbixin, tocotrienols and tocopherols biosynthesis, use and industrial applications of annatto extracts, as well as its nutraceutical potential and its benefits for human health. Fil: Raddatz Mota, Denise. Universidad Autónoma Metropolitana; México Fil: Pérez Flores, Laura J.. Universidad Autónoma Metropolitana; México Fil: Carrari, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Mendoza Espinoza, José A.. Universidad Autónoma Metropolitana; México. Universidad Nacional Autónoma de México; México Fil: de León Sánchez, Fernando Díaz. Universidad Autónoma Metropolitana; México Fil: Pinzón López, Luis L.. Instituto Tecnológico de Conkal; México Fil: Godoy Hernández, Gregorio. Centro de Investigación Científica de Yucatán. Unidad de Bioquímica y Biología Molecular de Plantas; México Fil: Rivera Cabrera, Fernando. Universidad Autónoma Metropolitana; México

Título en español: Infectividad y efectividad de rizobios aislados de Suelos de la Costa Caribe Colombiana en Vigna unguiculata Título en ingles: Infectivity and effectiveness of isolated rhizobia from colombian caribbean soils in Vigna unguiculata Título corto: Infectividad y efectividad de rizobios aislados de Suelos Resumen: Es el primer estudio en Colombia que abarca una evaluación de rizobios nativos asociados a frijol Caupí (Vigna unguiculata L. Walp.) en los departamentos del Cesar y la Guajira. En esta investigación, se demostró que la utilización de aislamientos de rizobios nativos aislados a partir de nódulos, mejoraron el desarrollo del frijol Caupí (Vigna unguiculata L. Walp.), siendo estas bacterias más eficientes que los tratamientos químicos y absolutos (sin inóculo ni fertilización) y que las cepas inducidas mejorando además, la fijación biológica de nitrógeno y la tasa fotosintética. Como aportes del estudio, se determinó que en condiciones de invernadero la fertilización biológica fue más eficiente que la química y que, de acuerdo a los resultados obtenidos de las diferentes variables agronómicas evaluadas, esto podría influir positivamente en los rendimientos nutricionales del cultivo, base alimentaria de los sistemas ganaderos de estas regiones del país y fuente alimenticia de la comunidad indígena y de bajos recursos económicos. Palabras clave Nodulación, fijación Biológica de Nitrógeno, Fertilización, Tasa Fotosintética Abstract: This is the first study in Colombia which covers an evaluation of native rhizobium associated to the Caupí bean (Vigna unguiculata L. Walp.) in the departaments of Cesar and Guajira. In this research it was demonstrated that the use of native rhizobium isolated from nodes, improved the development of the Caupí bean (Vigna unguiculata L. Walp.), being this bacteria more efficient than the chemical and absolute treatments (without inoculum and fertilization) also improving the biological nitrogen fixation and the photosynthetic rate. As contribution of the study, it was determined that in greenhouse conditions and according to the results obtained from differents measured agronomic variables, this could influence positively in the nutritional performance of the crop, basis of food of the cattle system of this regions of the country and the food source of the indigenous community of low economic income. Key words: Native Rhizobium, biological nitrogen fixation, fertilization, photosynthetic rate. Recibido: febrero 3 de 2014 Aprobado: octubre 10 de 2014

The relation between fatty acid accumulation, activity of acetyl-CoA carboxylase (ACC), and consequently lipid accumulation was studied in the microalgae Chlorella vulgaris co-immobilized with the plant growth-promoting bacterium Azospirillum brasilense under dark heterotrophic conditions with Na acetate as a carbon source. In C. vulgaris immobilized alone, cultivation experiments for 6 days showed that ACC activity is directly related to fatty acid accumulation, especially in the last 3 days. In co-immobilization experiments, A. brasilense exerted a significant positive effect over ACC activity, increased the quantity in all nine main fatty acids, increased total lipid accumulation in C. vulgaris, and mitigated negative effects of nonoptimal temperature for growth. No correlation between ACC activity and lipid accumulation in the cells was established for three different temperatures. This study demonstrated that the interaction between A. brasilense and C. vulgaris has a significant effect on fatty acid and lipid accumulation in the microalgae.

A comprehensive conformational analysis for the anticancer agent pironetin (1) was achieved by molecular modeling using density functional theory calculations at the B3PW91/DGTZVP level in combination with calculated and experimental (1)H-(1)H coupling constants comparison. Two solvent-dependent conformational families (L and M) were revealed for the optimum conformations. Docking studies of the pironetin-tubulin complex determined a quantitative model for the hydrogen-bond interactions of pironetin through the αAsn249, αAsn258, and αLys352 amino groups in α-tubulin, which supported the formation of a covalent adduct between the αLys352 and the β carbon atom of the α,β-unsaturated lactone. Saturation-transfer difference NMR spectroscopy confirmed that pironetin binds to tubulin, while molecular dynamics exposed a distortion of the tubulin secondary structure at the H8 and H10 α-helices as well as at the S9 β-sheet, where αLys352 is located. A large structural perturbation in the M-loop geometry between the αIle274 and αLeu285 residues, an essential region for molecular recognition between α-α and β-β units of protofilaments, was also identified and provided a rationale for the pironetin inhibitory activity.

Bovine trichomonosis (BT) is a sexually transmitted disease that is considered a cause of early reproductive failure in cattle under extensive management conditions. Recently, Tritrichomonas foetus was detected in 41.5% of herds from one representative beef cattle breed (Asturiana de la Montaña; AM) reared in traditional mountain systems in Spain. The objective of the present study was to evaluate the effect of BT on reproductive performance and the economic consequences in AM herds. The benefits of a control program based on testing and culling infected bulls were also studied by comparing T. foetus prevalence and reproductive data before and after the implementation of the control measures. In infected herds, T. foetus infection increased calving intervals by 79 days (P0.0001) and resulted in a higher percentage of cows-not-in calf (36% vs. 19%; P0.001). An economic analysis showed that BT could reduce income by 68.7% in AM herds. The implementation of the control program decreased calving intervals (P0.0001) and increased calving percentage (P0.05). T. foetus prevalence showed a significant decline compared with the prevalence before implementing the control program (P0.05). Nevertheless, after 2 years, the herd prevalence did not decrease (12.7-13.6%; P0.05) and the herd incidence was 22.72%. The testing and culling policy was effective in improving reproductive efficiency but the complete elimination of BT without substantial changes in management appears unlikely because putative risk factors associated with the disease are present in the management of this breed.

Mexico is the world’s leading Persian lime (Citrus latifolia T.) fruit producer and exporter. The use of rootstocks in citrus may increase fruit quality; however, the most used rootstock in Mexico is Sour orange, which is susceptible to the citrus tristeza virus. The objetive of this work was to evaluate the effect of rootstock (Sour orange, Volkamerian lemon, Flying dragon, Swingle citrumelo and C-35 citrange) on Persian lime fruit quality parameters. Peel thickness, juice content, pH, total titratable acidity (TA), total soluble solids (TSS), weight loss, pectin content, organic acids, sugars and characterization of essential oil components were evaluated. The use of rootstocks had no effect on juice content, pH, TA, organic acids (oxalic, malic and ascorbic) and sugars content (fructose, glucose and sucrose). Fruits from trees grafted on Sour orange and Volkamerian lemon showed the highest pectin yield, while Volkamerian lemon and Flying dragon showed the highest content of citric acid. The aromatic profile of Persian lime essential oil was affected by rootstock type. Fruits from trees grafted on Flying dragon showed a darker and more intense green color, the highest values of TSS and lower percentage of weight loss.

Cisplatin remains one of the most effective current chemotherapeutic agents; however, metal complexes synthesis has increased in order to produce new anti-neoplastic drugs with DNA binding and apoptotic activities in tumor cells and less toxicity for patients. In this study, we evaluated the cytotoxic activity of a novel copper(II) complex (LQM402) against cervical cancer cell lines and found that LQM402 exhibited selective cytotoxicity against HeLa and Ca Ski cells. FITC-annexin assay and DNA fragmentation indicated that apoptosis could be involved in HeLa cell death. Caspase 3/7 and cytochrome c analysis by immunoblotting suggest the intrinsic pathway. LQM402 is a lipid peroxidation inductor according to TBARS production. Additionally, the Ames and micronucleus tests demonstrated non-genotoxic activity for this compound in Salmonella typhimurium and CD1 mice, respectively. Therefore, LQM402 may be a promising and safe anti-cervical cancer compound.

Achiote (Bixa orellana) is a plant used for obtaining a natural dye rich on carotenoids (mainly bixin and norbixin); it is also the plant species with the highest content of tocotrienols in nature. In the present work, the pigment extraction yield of seven Mexican accessions of Bixa orellana was quantified. Also color parameters and content of tocotrienols, tocopherols, norbixin, bixin, total phenolic compounds and antioxidant capacity were evaluated in the corresponding annatto extracts. The highest percentage of pigment extraction yield was obtained with KOH (4.84%). Accessions 43 (L*= 4.01 ± 0.79, C*= 7.33 ± 1.07, h= 25.76 ± 6.35) and 50 (L*= 3.17 ± 0.64, C*= 6.81 ± 0.53, h= 26.41 ± 4.41) had the lowest color values, meaning these accessions had a darker and redder color. Four accessions showed the highest content of bixin: accession 48 (3.1%), 45 (2.6%) 43 (2.4%) and 47 (2.2%). Accession 50 had showed the highest content of total phenolic compounds and of tocotrienols (T3), mainly the isoform δ-T3 (5.03 ± 0.64 mg g−1 Seed Dry Weight), as well as the highest antioxidant capacity. El achiote (Bixa orellana) es una planta utilizada para obtener un colorante natural rico en carotenoides (principalmente bixina y norbixina); además, es la especie vegetal con el mayor contenido de tocotrienoles. En este trabajo, se determinó el rendimiento de extracción de pigmento de siete accesiones mexicanas de Bixa orellana. También se evaluaron los parámetros de color y el contenido de tocotrienoles, tocoferoles, norbixina, bixina, compuestos fenólicos totales y la capacidad antioxidante en extractos de annato. El mayor porcentaje de rendimiento de extracción de pigmento fue obtenido con KOH (4.847905%). Las accesiones 43 (L*= 4.01 ± 0.79, C*= 7.33 ± 1.07, h= 25.76 ± 6.35) y 50 (L*= 3.17 ± 0.64, C*= 6.81 ± 0.53, h= 26.41 ± 4.41) presentaron los valores más bajos de los párametros de color, lo que significa que estas accesiones tuvieron un color más oscuro y más rojo. Cuatro accesiones mostraron el mayor contenido de bixina: accesión 48 (3.1%), 45 (2.6%) 43 (2.4%) and 47 (2.2%). La accession 50 mostró el mayor contenido de compuestos fenólicos totales y de tocotrienoles (T3), principalmente la isoforma δ-T3 (5.03 ± 0.64 mg g-1 Peso Seco), así como también la mayor capacidad antioxidante. Fil: Raddatz Mota, D.. Universidad Autónoma Metropolitana; México Fil: Pérez Flores, L. J.. Universidad Autónoma Metropolitana; México Fil: Carrari, Fernando Oscar. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Insani, Ester Marina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Asis, Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina Fil: Mendoza Espinoza, J. A.. Universidad Nacional Autónoma de México; México Fil: Díaz de León Sánchez, F.. Universidad Autónoma Metropolitana; México Fil: Rivera Cabrera, F.. Universidad Autónoma Metropolitana; México

a b s t r a c t Mammillaria fraileana is a major pioneer, small cactus that harbors endophytic bacteria that have plant growth-promoting traits, including rock-weathering capacity. Our working hypothesis was that this func- tional group of endophytic bacteria assists in establishing pioneer plants on rocks. When these endophytic bacteria were inoculated on seedlings grown in rock substrate, mobilization of elements from the sub- strate increased at variable levels across combinations of substrates and inoculants. In plants grown in the rhyodacite substrate, where these cacti naturally grow, increased mobilization occurred in plants inoculated with several strains. Promotion of plant growth, manifested as an increase in dry weight, was greater in cacti inoculated with Enterobacter sakazakii M2PFe. Accumulation of nocturnal acids, indicating photosynthesis by crassulacean acid metabolism, was superior in plants inoculated with the endophytes Azotobacter vinelandii M2Per and Pseudomonas putida M5TSA. Inoculation with endophytes can stimulate plant growth of M. fraileana by mobilizing elements from rock, which can lead to higher photosynthetic activity and accumulation of biomass. Inoculation with P. putida M5TSA also led to accumulation of more total nitrogen than plants inoculated with a control nitrogen-fixing bacteria. Evidence of endophytic col- onization is provided after initial inoculation of seedlings and re-isolation and sequencing of 16S DNA of recovered bacteria from developing disinfected plants. The associative interaction between pioneer cacti and their bacterial endophytes enable the host plants to grow in places where plants do not nor- mally grow. Through colonization and establishment of pioneer plants, soil is created, which facilitates colonization by other desert species and contributes to the diversity of dry lands.

Bovine trichomonosis (BT) and bovine genital campylobacteriosis (BGC) are sexually transmitted diseases that can be important infectious causes of reproductive failure in extensively managed beef cattle where natural mating is a common practice. However, their prevalence in Europe was thought to be insignificant or very low. The purpose of this study was to investigate the prevalence and risk factors associated with BT and BCG in a representative beef cattle breed, Asturiana de la Montana (AM), which is usually managed extensively in the mountain areas of Northern Spain and putative risk factors associated with the two diseases are present on most farms holding AM cattle. Preputial smegma samples were collected from 103 bulls belonging to 65 herds. Pathogen detection was undertaken using culture and PCR. Two scraping methods for sample collection (AI pipette and plastic scraper), as well as different culture media and DNA extraction methods were evaluated on field samples. Campylobacter fetus veneralis infection was not detected in any animal in any herd. However, Tritrichomonas foetus infection was demonstrated in 32% (33/103) and 41.5% (27/65) of bulls and herds tested, respectively. AM bulls older than 3 years (39.7%) were more likely to be infected than young bulls (16%) (OR = 3.45, CI = 1.07–11.19). An increase in repeat breeder cows was reported in herds from which T. foetus was detected (OR = 5.2, CI = 1.5–17.18). These findings highlight the re-emergence of this disease in extensively managed beef cattle in Spain. For routine diagnosis, the use of a culture technique and PCR in combination is advisable for testing smegma samples under field conditions.

The presence of Burkholderia, Cupriavidus, and Ralstonia species in northeastern Mexico was investigated. An analysis of the root surrounding soil from different agricultural plants led to the isolation of Burkholderia and Cupriavidus species but no Ralstonia strains. Most Cupriavidus species were unknown and grouped into two clusters according to ARDRA profiles. The 16S rRNA sequence analysis showed that the Cupriavidus isolates were highly related among them and with different Cupriavidus species with validated names. However, SDS-PAGE profiles were distinct among the different ARDRA profiles and to other Cupriavidus species examined, suggesting new species in the genus. This shows that Cupriavidus is more widely associated with plants than previously appreciated. The BCC isolate was 99% similar to B. cenocepacia by recA sequence analysis. Additionally, most Cupriavidus strains from the two largest groups grew on media containing up to 0.1 mg/ml of copper, 10.0 mg/ml arsenic and 1.0 mg/ml zinc. Burkholderia strains grew on media containing up to 10.0 mg/ml zinc, 5.0 mg/ml arsenic and 0.1 mg/ml copper.

Tritrichomonas foetus has been identified as the causative agent of feline intestinal trichomonosis, characterized by clinical signs of chronic large bowel diarrhoea. This disease has been reported in cats from the USA, Europe and Australia. However, its epidemiology is still unclear. The aim of the present study was to describe T. foetus infection in a Persian cattery in Spain. T. foetus infection was sequentially diagnosed in 20 cats by direct faecal smear examined under the microscope, specific culture (In Pouch TF medium) and PCR. A standard coprological sedimentation method was also performed in order to screen for other intestinal parasites in all the cats included. In addition, sera were tested for IgG antibodies against Leishmania infantum, Toxoplasma gondii, and for the detection of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Five out of 20 cats were positive for T. foetus (25%), two of them by microscopy, culture and PCR and three by culture and PCR. No association was found between T. foetus infection and age or sex. L. infantum and T. gondii seroprevalence rates were 15% and 10%, respectively. The prevalence of FeLV p27 antigen and of FIV antibodies in the study population was zero. Cystoisospora spp. oocysts were detected in one cat. These preliminary results show that the transmission of T. foetus infection in cluster conditions may occur between asymptomatic cats and young or immunocompromised animals.

3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, were originally designed to reduce cholesterol biosynthesis and have been extensively used as prevention drugs against hyperlipidemia and cardiovascular conditions. Recently, these compounds have been shown to display chemopreventive activity against cancer. However, the effects of statins on cancer are not completely understood. For this reason, we have studied the cytotoxic effect of rosuvastatin and fluvastatin on three cell tumoral lines: human larynx carcinoma (HEp-2), human nasopharyngeal carcinoma (KB), and human epithelial carcinoma (HeLa). We have found that only fluvastatin has relevant activity against the tumoral cell lines assayed and the capacity to arrest G1-phase, whereas a significant decline was observed in the S-phase percentage. Fluvastatin IC50 were 2.43±0.56 μg/mL (HEp-2), 2.29±0.19 μg/mL (KB), and 5.02±1.52 μg/mL (HeLa), whereas rosuvastatin showed poor activity. These results indicate that the cytotoxic effect of fluvastatin may not depend directly on HMG-CoA reductase inhibition. The antitumor statins effect needs further investigation.

To determine the effect of pH-stat as compared with alpha-stat management on brain oxygenation, level of striatal extracellular dopamine, phosphorylation, and levels of protein kinase B (Akt) and cyclic adenosine 3', 5'-monophosphate response element-binding protein (CREB), and levels of extracellular signal-regulated kinase (ERK)1/2, Bcl-2, and Bax in a piglet model of deep hypothermic circulatory arrest (DHCA).The piglets were placed on cardiopulmonary bypass (CPB), cooled with pH-stat or alpha-stat to 18 degrees C, subjected to 90 minutes of DHCA, rewarmed, weaned from CPB, and maintained for two hours recovery. The cortical oxygen was measured by: quenching of phosphorescence; dopamine by microdialysis; phosphorylation of CREB (p-CREB), ERK (p-ERK) 1/2, Akt (p-Akt), and level of Bcl-2, Bax by Western blots.Oxygen pressure histograms for the microvasculature of the cortex show substantially higher oxygen levels during cooling and during the oxygen depletion period after cardiac arrest (up to 15 minutes) when using pH-stat compared with alpha-stat management. Significant increases in dopamine occurred at 45 minutes and 60 minutes of DHCA in the alpha-stat and pH-stat groups, respectively. The p-CREB and p-Akt in the pH-stat group were significantly higher than in the alpha-stat group (140 +/- 9%, p0.05 and 125 +/- 6%, p0.05, respectively). There was no significant difference in p-ERK1/2 and Bax. The Bcl-2 increased in the pH-stat group to 121 +/- 4% (p0.05) compared with the alpha-stat group. The ratio Bcl-2:Bax increased in the pH-stat group compared with the alpha-stat group.The increase in p-CREB, p-Akt, Bcl-2, Bcl-2/Bax, and delay in increase of dopamine indicated that pH-stat, in the piglet model, prolongs "safe" time of DHCA and provides some brain protection against ischemic injury.

In non-photosynthetic tissues, mitochondria are the main source of energy and of reactive oxygen species. Accumulation of high levels of these species in the cell causes damage to macromolecules including several proteins and induces changes in different metabolic processes. Fruit ripening has been characterized as an oxidative phenomenon; therefore, control of reactive oxygen species levels by mitochondrial antioxidants plays a crucial role on this process. In this work, ascorbate-glutathione cycle components, hydrogen peroxide levels and the proteomic profile of carbonylated proteins were analyzed in mitochondria isolated from tomato (Solanum lycopersicum) fruit at two ripening stages. A significant increase on most ascorbate-glutathione cycle components and on carbonylated proteins was observed in mitochondria from breaker to light red stage. Enzymes and proteins involved in diverse cellular and mitochondrial metabolic pathways were identified among the carbonylated proteins. These results suggest that protein carbonylation is a post-translational modification involved in tomato fruit ripening regulation.

Resumen A polymerase chain reaction (PCR) was applied to detect genetically modified (GM) maize and soybean food product, using specific 35S promoter primers for inserted chimerical genes in maize or soybean. The PCR detected food products that include ingredients obtained from GMOs in maize grains and flour, as well as processed in foods such as tortillas (Mexican crepe), corn chips, corn and soybean oils. Beside the promoter, the PCR also detected zeine and lectin genes for maize and soybean, respectively, which confirmed the identity of the analyzed samples. The presence of transgenic material was also confirmed by detecting the terminator Tnos region. High quality DNA from samples permitted an accurate detection of GM in food products while low quality DNA could lead to false negatives. The event Bt-176 and non-GM maize were used as positive and negative controls, respectively. Three types of GM food-products (grain, flour and soybean oil) resulted positive, while flour products (tortilla and...

Azospirillum brasilense 8-I was chromosomally labeled with green fluorescent protein (gfp) genes, using either the native promoterless gfp gene or the mutant gfpmut2 gene under the transcriptional control of the neomycin phosphate transferase (npt2) promoter inserted into Tn5 suicide plasmid vectors. One A. brasilense exconjugant, showing a steady and strong fluorescence following irradiation with 365-nm UV light was characterized in detail. This strain, A. brasilense 8-I-gfp showed increased N2-fixation of approximately threefold, up to a twofold increase in exopolysaccharide production, and a significant decrease in indole-3-acetic acid and poly-β-hydroxybutyrate production over the parental strain. Sequence analysis showed that the Tn5 carrying the gfp gene was inserted in the clpX gene encoding a heat-shock protein. This data is consistent with a model in which the observed physiological changes are a consequence of pleiotropic changes that occur as a consequence of impaired heat shock (stress) protein synthesis. In summary, (i) chromosomally labelled Azospirillum brasilense was obtained carrying either native or mutant gfp genes, (ii) Pleiotropic physiological effects were caused by disruption of the clpX gene as the consequence of the insertion, (iii) a new indole-3-acetic acid-attenuated mutant of A. brasilense producing only 0.25% of the indole-3-acetic acid produced by the wild-type is presented.

PEMEX Ex plo ra tion and Pro duc tion (PEP) per forms vent ing of as so ci ated gas through high torch-type burn ers in its pro duc tion fa cil i ties in the south ern most part of the Gulf of Mex ico (Sonda de Campeche), al low ing con trol of op er a tion pres sures of sep a ra tors and pipe lines in such fa cil i ties. This study fo cuses in es ti mat ing the amount of at mo spheric emis sions orig i nated from burn ers in PEP’s North east Ma rine Re gion. Thus, an emis sion in ven tory for six dif fer e nt study ep i sodes be tween No vem ber 2000 and No vem ber 2001 was elab o rated, with the ob jec tive of di ag nos ing the emis sions’ be hav iors through out dif fer ent me te o ro log i cal con di tions. The in ven tory was gen er ated for CO, CO2 , SO2, ni tro gen ox ides, to tal sus pended par ti cles and un burned hy dro car bons. The in ven tory was as sem bled us ing emis sion fac tors that ac count for the o ret i cal com bus tion in ef fi cien cies due to me te o ro log i cal con di tions. The re sults show con sid er able amounts of H2 S and un burned or ganic com pounds due to com bus tion in ef fi cien cies that ranged be tween 22% and 44%.

International audience; Frankia strains are nitrogen-fixing soil actinobacteria that can form root symbioses with actinorhizal plants. Phylogenetically, symbiotic frankiae can be divided into three clusters, and this division also corresponds to host specificity groups. The strains of cluster II which form symbioses with actinorhizal Rosales and Cucurbitales, thus displaying a broad host range, show suprisingly low genetic diversity and to date can not be cultured. The genome of the first representative of this cluster, Candidatus Frankia datiscae Dg1 (Dg1), a microsymbiont of Datisca glomerata, was recently sequenced. A phylogenetic analysis of 50 different housekeeping genes of Dg1 and three published Frankia genomes showed that cluster II is basal among the symbiotic Frankia clusters. Detailed analysis showed that nodules of Datisca glomerata, independent of the origin of the inoculum, contain several closely related cluster II Frankia operational taxonomic units. Actinorhizal plants and legumes both belong to the nitrogen-fixing plant clade, and bacterial signaling in both groups involves the common symbiotic pathway also used by arbuscular mycorrhizal fungi. However, so far, no molecules resembling rhizobial Nod factors could be isolated from Frankia cultures. Alone among Frankia genomes available to date, the genome of Dg1 contains the canonical nod genes nodA, nodB and nodC known from rhizobia, and these genes are arranged in two operons which are expressed in Datisca glomerata nodules. Furthermore, Frankia Dg1 nodC was able to partially complement a Rhizobium leguminosarum A34 nodC::Tn5 mutant. Phylogenetic analysis showed that Dg1 Nod proteins are positioned at the root of both alpha- and beta-rhizobial NodABC proteins. NodA-like acyl transferases were found across the phylum Actinobacteria, but among Proteobacteria only in nodulators. Taken together, our evidence indicates an Actinobacterial origin of rhizobial Nod factors.

The objective of this study was to assess the importance of stay-green on grain yield under heat and combined heat and drought stress and to identify the associated vegetative indices allowing higher throughput in order to facilitate the identification of climate resilient germplasm. Hybrids of tropical and subtropical adaptation were evaluated under heat and combined heat and drought stress in 2014 and 2015. Five weekly measurements with an airplane mounted multispectral camera starting at anthesis were used to estimate the area under the curve (AUC) for vegetation indices during that period; the indices were compared to the AUC (AUCSEN) for three visual senescence scores taken two, four, and six weeks after flowering and a novel stay-green trait (AUC for stay-green; AUCSG) derived from AUCSEN by correcting for the flowering date. Heat and combined heat and drought stress reduced grain yield by 53% and 82% (relative to non-stress trials reported elsewhere) for trials carried out in 2014 and 2015, respectively, going along with lower AUCSG in 2014. The AUCSG was consistently correlated with grain yield across trials and years, reaching correlation coefficients of 0.55 and 0.56 for 2014 and 2015, respectively. The AUC for different vegetative indices, AUCNDVI (rgGY = 0.62; rgAUCSG = 0.72), AUCHBSI (rgGY = 0.64; rgAUCSG = 0.71), AUCGRE (rgGY = 0.57; rgAUCSG = 0.61), and AUCCWMI (rgGY = 0.63; rgAUCSG = 0.75), were associated with grain yield and stay-green across experiments and years. Due to its good correlation with grain yield and stay-green across environments, we propose AUCNDVI for use as an indicator for stay-green and a long grain filling. The trait AUCNDVI can be used in addition to grain yield to identify climate-resilient germplasm in tropical and subtropical regions to increase food security in a changing climate.

Objetivos. Implementar un sistema para el diagnóstico remoto de tuberculosis y multidrogorresistencia (MDR) usando el método Microscopic-Observation Drug Susceptibility Assay (MODS) en el Laboratorio de Micobacterias del Centro de Excelencia en Tuberculosis de Trujillo (CENEX-Trujillo). El sistema incluyó una variante de un algoritmo de reconocimiento de Mycobacterium tuberculosis recientemente reportado a partir de imágenes digitales de cultivos MODS de muestras de esputo. Materiales y métodos. Se optimizó un algoritmo de reconocimiento por medio de un reentrenamiento del modelo estadístico basado en imágenes digitales de cultivos MODS provenientes del Laboratorio de Micobacterias del CENEX-Trujillo. Se obtuvieron imágenes de 50 cultivos MODS positivos de pacientes con sospecha de tuberculosis multidrogorresistente entre enero y octubre de 2012 en el CENEX-Trujillo. Resultados. La sensibilidad y la especificidad en objetos, para reconocer cordones de tuberculosis fueron de 92,04% y de 94,93% respectivamente. La sensibilidad y la especificidad en foto, para determinar un campo positivo a tuberculoisis fueron 95,4% y de 98,07% respectivamente. Conclusiones. Los resultados demostraron la factibilidad de la implementación de telediagnóstico en lugares remotos, el cual puede contribuir con la detección temprana de tuberculosis multidrogorresistente mediante el método MODS Objectives. To implement a system for remote diagnosis of tuberculosis and multidrug resistance (MDR) using the Microscopic-Observation Drug Susceptibility Assay (MODS) method in the Mycobacteria Laboratory, Trujillo Center of Excellence in Tuberculosis (CENEX-Trujillo). The system included a variant of an algorithm for recognition of Mycobacterium tuberculosis recently reported from digital images of MODS cultures of sputum samples. Materials and methods. The recognition algorithm was optimized using a retraining statistical model based on digital images of MODS cultures from CENEX-Trujillo. Images of 50 positive MODS cultures of patients with suspected multidrug-resistant tuberculosis were obtained between January and October 2012 in the CENEX-Trujillo. Results. The sensitivity and specificity to recognize strings of tuberculosis were 92.04% and 94.93% respectively using objects. The sensitivity and specificity to determine a positive tuberculosis field were 95.4% and 98.07% respectively using pictures. Conclusions. The results demonstrated the feasibility of the implementation of telediagnostics in remote locations, which may contribute to the early detection of multidrug-resistant tuberculosis by MODS method

ADP-glucose pyrophosphorylase (AGPase) regulates starch biosynthesis in higher plants and microalgae. This study measured the effect of the bacterium Azospirillum brasilense on AGPase activity in the freshwater microalga Chlorella vulgaris and formation of starch. This was done by immobilizing both microorganisms in alginate beads, either replete with or deprived of nitrogen or phosphorus and all under heterotrophic conditions, using d-glucose or Na-acetate as the carbon source. AGPase activity during the first 72h of incubation was higher in C. vulgaris when immobilized with A. brasilense. This happened simultaneously with higher starch accumulation and higher carbon uptake by the microalgae. Either carbon source had similar effects on enzyme activity and starch accumulation. Starvation either by N or P had the same pattern on AGPase activity and starch accumulation. Under replete conditions, the population of C. vulgaris immobilized alone was higher than when immobilized together, but under starvation conditions A. brasilense induced a larger population of C. vulgaris. In summary, adding A. brasilense enhanced AGPase activity, starch formation, and mitigation of stress in C. vulgaris.