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Cocoa is one of the most important tropical fruits worldwide, its importance lies in its use in the food, cosmetic and pharmaceutical industries. Cocoa yield has been affected by different environmental, cultural and phytosanitary aspects. The emergence of new growing areas allows exploring the possibility of generating new economic and ecological systems that comply with current trends in organic farming. For them, pre-harvest practices such as pruning and soil fertilization are two necessary tools to control the productivity of cocoa agroecosystems. Therefore, the objective of this research was to analyses the implementation of pre-harvest techniques and the quality soil to increase the yield in a cocoa agroecosystem in an emerging zone in the Huasteca Potosina of Mexico. The work was carried out in an emerging zone in the cultivation of cocoa in three different zones delimited in 30 × 30 m. Thinning and pruning practices were carried out to keep the space clear and observe the influence on fruit yield. In addition, the quality of the soil was measured in terms of physical conditions and nutrient content. 25 kg/ha of nitrogen, 22 kg/ha of P2O5, 24 kg/ha of K2O and 4 kg/ha of magnesium were added following the recommendation of the fertilization laboratory. The physical properties of the pod were also analyzed, such as size, weight, number of grains and color. And some of the cocoa bean such as size, weight and hardness, all these parameters to measure the average yield of cocoa pods. The results show a clear influence of the soil quality and pre-harvest practices on the physical properties of the fruit and the total yield from 472.36 ± 52.01 to 520.06 ± 104.91 kg. However, other aspects are also modified, such as the increase in the size of the pod and the cocoa bean. Other aspects such as the color of the pod and the hardness of the grain do not present statistical difference. In conclusion, pre-harvest practices together with the application of fertilizers are factors that positively influence the yield of cocoa fruit. Some of the limitations of this research were the age of the plants and the local plant species.

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Plants are continuously exposed to stress conditions, such that they have developed sophisticated and elegant survival strategies, which are reflected in their phenotypic plasticity, priming capacity, and memory acquisition. Epigenetic mechanisms play a critical role in modulating gene expression and stress responses, allowing malleability, reversibility, stability, and heritability of favourable phenotypes to enhance plant performance. Considering the urgency to improve our agricultural system because of going impacting climate change, potential and sustainable strategies rely on the controlled use of eustressors, enhancing desired characteristics and yield and shaping stress tolerance in crops. However, for plant breeding purposes is necessary to focus on the use of eustressors capable of establishing stable epigenetic marks to generate a transgenerational memory to stimulate a priming state in plants to face the changing environment.

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BACKGROUND AND PURPOSE: The development of new MR imaging scanners with stronger gradients and improvement in coil technology, allied with emerging fast imaging techniques, has allowed a substantial reduction in MR imaging scan times. Our goal was to develop a 10-minute gadolinium-enhanced brain MR imaging protocol with accelerated sequences and to evaluate its diagnostic performance compared with the standard clinical protocol. MATERIALS AND METHODS: Fifty-three patients referred for brain MR imaging with contrast were scanned with a 3T scanner. Each MR image consisted of 5 basic fast precontrast sequences plus standard and accelerated versions of the same postcontrast T1WI sequences. Two neuroradiologists assessed the image quality and the final diagnosis for each set of postcontrast sequences and compared their performances. RESULTS: The acquisition time of the combined accelerated pre- and postcontrast sequences was 10 minutes and 15 seconds; and of the fast postcontrast sequences, 3 minutes and 36 seconds, 46% of the standard sequences. The 10-minute postcontrast axial T1WI had fewer image artifacts (P < .001) and better overall diagnostic quality (P < .001). Although the 10-minute MPRAGE sequence showed a tendency to have more artifacts than the standard sequence (P = .08), the overall diagnostic quality was similar (P = .66). Moreover, there was no statistically significant difference in the diagnostic performance between the protocols. The sensitivity, specificity, and accuracy values for the 10-minute protocol were 100.0%, 88.9%, and 98.1%. CONCLUSIONS: The 10-minute brain MR imaging protocol with contrast is comparable in diagnostic performance with the standard protocol in an inpatient motion-prone population, with the additional benefits of reducing acquisition times and image artifacts.

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Capsinoids are non-pungent analogues of capsaicinoids in pepper (Capsicum spp). The absence of pungency, in addition to their biological activities similar to that of capsaicinoids such as anti-inflammatory, antimicrobial, and antioxidant properties, makes capsinoids an excellent option for increasing use in human and animal nutrition, as well as health and pharmaceutical industries. There are only few sources of pepper producing capsinoids, and one of them (accession 509-45-1), Capsicum annuum L., is a potential source for increasing capsinoids content using strategies as controlled elicitation during plant production in the greenhouse. In this research we evaluated the effect of weekly and one-day-before-harvest foliar applications of hydrogen peroxide, salicylic acid and a xyloglucan oligosaccharide on the concentration of capsiate in fruits of this pepper accession, as well as the gene expression of phenylalanine ammonia-lyase (pal), putative aminotransferase (pamt), capsaicin synthase (at3) and ß-keto acyl synthase (kas). Results showed that the two tested concentrations of H2O2 significantly increased capsiate content and gene expression associated with capsaicinoids (pamt, at3 and kas) and the phenylpropanoids (pal) pathways. Plant yield was not affected using this induction strategy. Our results indicated that the pre-harvest and weekly application of hydrogen peroxide and xyloglucan oligosaccharide improved production of capsiate in C. annuum L.

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Cancer is a leading cause of death worldwide with colorectal cancer (CRC) ranking as the third contributing to overall cancer mortality. Non-digestible compounds such as dietary fiber have been inversely associated with CRC in epidemiological in vivo and in vitro studies. In order to investigate the effect of fermentation products from a whole non-digestible fraction of common bean versus the short-chain fatty acid (SCFAs) on colon cancer cells, we evaluated the human gut microbiota fermented non-digestible fraction (hgm-FNDF) of cooked common bean (Phaseolus vulgaris L.) cultivar Negro 8025 and a synthetic mixture SCFAs, mimicking their concentration in the lethal concentration 50 (SCFA-LC50) of FNDF (hgm-FNDF-LC50), on the molecular changes in human colon adenocarcinoma cells (HT-29). Total mRNA from hgm-FNDF-LC50 and SCFA-LC50 treated HT-29 cells were used to perform qPCR arrays to determine the effect of the treatments on the transcriptional expression of 84 genes related to the p53-pathway. This study showed that both treatments inhibited cell proliferation in accordance with modulating RB1, CDC2, CDC25A, NFKB and E2F genes. Furthermore, we found an association between the induction of apoptosis and the modulation of APAF1, BID, CASP9, FASLG, TNFR10B and BCL2A genes. The results suggest a mechanism of action by which the fermentation of non-digestible compounds of common bean exert a beneficial effect better than the SCFA mixture by modulating the expression of antiproliferative and pro-apoptotic genes in HT-29 cells to a greater extent, supporting previous results on cell behavior, probably due to the participation of other compounds, such as phenolic fatty acids derivatives and biopetides.

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The complete genome sequence of a distinct variant of tomato yellow leaf curl virus-Israel (TYLCV-IL) and the DNA-A sequence of a new strain of tomato severe leaf curl virus (ToSLCV) isolated in San Luis Potosi, Mexico, are described and analyzed. The TYLCV-IL[MX:SLP:11] variant differs from all TYLCV-IL isolates described so far by a unique 42-nt duplicated sequence comprising a part of the conserved stem-loop element of the virion-strand replication origin and adjacent regulatory sequences. TYLCV-IL[MX:SLP:11] was associated with tomato chino La Paz virus (ToChLPV-B[MX:SLP:11]) in a Solanum pimpinellifolium plant, and with pepper huasteco yellow vein virus (PHYVV-[MX:SLP:11]) and ToSLCV-GT[MX:SLP:11] in a Solanum lycopersicum plant. In addition, a distinct ToSLCV exhibiting low sequence identity (<89 %) to other ToSLCV isolates from Mexico was found in a tomato plant collected in the same field. Sequence analysis of this new ToSLCV strain indicates that it is a recombinant of close relatives of ToSLCV-GT[MX:SLP:11] and ToChLPV-B[MX:SLP:11] found in mixed infections with TYLCV-IL[MX:SLP:11].

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Xylan constitutes the second most abundant source of renewable organic carbon on earth and is located in the cell walls of hardwood and softwood plants in the form of hemicellulose. Based on its availability, there is a growing interest in production of xylanolytic enzymes for industrial applications. ß-1,4-xylan xylosidase (EC 3.2.1.37) hydrolyses from the nonreducing end of xylooligosaccharides arising from endo-1,4-ß-xylanase activity. This work reports the partial characterization of a purified ß-xylosidase from the native strain Aspergillus niger GS1 expressed by means of a fungal system. A gene encoding ß-xylosidase, xlnD, was successfully cloned from a native A. niger GS1 strain. The recombinant enzyme was expressed in A. niger AB4.1 under control of A. nidulans gpdA promoter and trpC terminator. ß-xylosidase was purified by affinity chromatography, with an apparent molecular weight of 90 kDa, and showed a maximum activity of 4,280 U mg protein(-1) at 70°C, pH 3.6. Half-life was 74 min at 70°C, activation energy was 58.9 kJ mol(-1), and at 50°C optimum stability was shown at pH 4.0-5.0. ß-xylosidase kept residual activity >83% in the presence of dithiothreitol (DTT), ß-mercaptoethanol, sodium dodecyl sulfate (SDS), ethylenediaminetetraacetate (EDTA), and Zn(2+). Production of a hemicellulolytic free xylosidase showed some advantages in applications, such as animal feed, enzymatic synthesis, and the fruit-juice industry where the presence of certain compounds, high temperatures, and acid media is unavoidable in the juice-making process.

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A 597 nt fragment from Tomato mottle Taino virus (ToMoTV) DNA-A, with 459 nt located upstream of the Replication-associated protein translation start codon, was tested for promoter activity in solanaceous plants. The promoter activity of this fragment (pRep(459::Rep)) was demonstrated when it was introduced upstream the uidA reporter gene into tobacco, potato and tomato plants by genetic transformation. It became active in 7-day-old transgenic tobacco seedlings as revealed by a vascular-specific pattern of gene expression which was maintained during the continued growth of the plant. Transformed potato and tomato plants also showed a vascular-specific pattern of expression. In comparative assays, pRep(459::Rep) showed an expression activity 10-40-fold less than the 35S promoter from Cauliflower mosaic virus. To delimit the minimal cis-acting elements necessary for vascular specificity of this promoter, a set of PCR deletion mutants of pRep(459::Rep) (pRep(459), pRep(324), pRep(203), pRep(145), pRep(132) and pRep(115)), were generated and used to transform tobacco plants. Transgenic tobacco plants belonging to all the pRep versions were blue stained in the vascular system except those from the pRep(115) version. The results described in this report demonstrate that the minimal sequences necessary for the pRep promoter activity are confined in a segment of 132 nts (located between the nts 2454 and 2585 of the ToMoTV DNA A) and that this promoter harbors those elements sufficient for vascular-specific expression.

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Over the last decade, the tomato production in Cuba has been affected by new whitefly-associated diseases. In addition to the well-documented presence of Tomato yellow leaf curl virus (TYLCV) along the island, the occurrence of bipartite begomoviruses has also been reported. One of them, tentatively named Tomato mottle Taino virus (ToMoTV), has now been cloned and characterized at the molecular level. Its genomic organization is similar to other bipartite geminiviruses. Phylogenetic analyses placed ToMoTV in a subcluster with other geminiviruses isolated in the Caribbean Basin: Tomato mottle virus (ToMoV), Bean dwarf mosaic virus, Abutilon mosaic virus, Sida golden mosaic virus and Potato yellow mosaic virus (PYMV). Biolistic inoculation of tobacco and tomato plants with cloned viral DNA showed that ToMoTV pseudorecombines with PYMV-GP as predicted by the identity of their iterative elements, whereas it does not show the same ability with ToMoV, even when their replication-associated proteins (Rep and REn) show the highest percentage of similarity. A comparative analysis of Rep proteins from begomoviruses that are able to produce viable reassortants suggests that some key elements for virus replication specificity are located in the first ten amino acids of this protein.

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We present a case of von Recklinghausen's disease in a patient whose pregnancy resulted in a stillbirth in the third trimester, probably due to placental insuficiency. Although neurofibromatosis is one off the most frequently occurring genetic diseases, its diagnosis is rarely made.

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A phylogenetic and structural analysis of the intergenic region of 22 dicot-infecting and 8 monocot-infecting geminiviruses was carried out. The analysis allowed the identification of iterative sequence motifs 8-12 nucleotides in length, whose organization (number, orientation, and spacing) is highly conserved within each of the three major lineages of dicot-geminiviruses, according to the phylogeny derived from the amino acid sequences of the replication-associated protein (AL1). The iterated elements differ in sequence even between closely related viruses, and are found in the vicinity of the putative TATA box of the AL1 gene in all dicot-infecting geminiviruses. Analogous elements were identified also in monocot-infecting geminiviruses, but the arrangement was different, since one of the iterative sequences is part of the conserved hairpin structure essential for replication of all the members of this viral family. We propose here that the iterated sequences are the specific binding sites of the geminiviral replication-associated proteins and show that the hypothesis is in agreement with the experimental data available to date. Additionally, a model of geminivirus replication that involves the participation of host transcription factors in the process is presented.

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