Oxidación y caracterización fisicoquímica de almidón de sagú “Marantha Arundinacea” para la elaboración de bioplástico

El uso excesivo de materiales derivados del petróleo como: combustibles, lubricantes, colorantes, disolventes, asfaltos, fibras textiles y plásticos ha generado a través del tiempo un grave problema ambiental, debido, a los largos periodos de degradación de estos materiales. Es por esto que hoy en día la investigación se centra en los plásticos ya que poseen poca vida útil, estos residuos terminan depositándose en rellenos sanitarios, océanos, lagos y demás fuentes hídricas generando la contaminación de este recurso vital para la vida, todo esto, provoca la muerte de especies animales y la desestabilización del ecosistema. La ciencia ha planteado soluciones tales como: reciclar, uso de papel y el desarrollo de materiales biodegradables siendo el almidón de sagú una alternativa como materia prima para la elaboración de este tipo de materiales. Esta investigación fue orientada a la elaboración de bioplástico utilizando como base almidón de sagú oxidado. Los estudios consisten en una caracterización fisicoquímica al almidón nativo, almidón oxidado y al bioplástico elaborado a base de almidón. Los análisis realizados fueron: porcentaje de grupos carbonilo y de grupos carboxilo, transparencia de los geles, microscopia electrónica de barrido donde se observó la apariencia irregular y los tamaños de los gránulos de almidón, además, el microscopio con EDS permitió observar las composiciones químicas simples de los gránulos, donde, los almidones oxidados tienen mayor porcentaje de oxigeno que el almidón nativo. En los análisis de difracción de rayos X se observa los patrones de difracción y el carácter semicristalino del almidón. El espectro de FT-IR muestra las bandas propias de los almidones nativos y oxidados. Por otra parte, las pruebas de solubilidad, transparencia muestran una ventaja del bioplástico elaborado con almidón oxidado

Oxidación y caracterización fisicoquímica de almidón de sagú “Marantha Arundinacea” para la elaboración de bioplástico

Excessive use of petroleum-based materials such as fuels, lubricants, dyes, solvents, asphalt, textile fibers and plastics has generated over time a serious environmental problem, due to long periods of degradation of these materials. That is why today’s research focuses on plastics because they have little life, these wastes end up being deposited in landfills, oceans, lakes and other water sources causing pollution of this vital resource for life, all this, kills animal species and ecosystem´s destabilization. Science has proposed solutions such as recycling, the use of materials made of paper, and the development of biodegradable materials, one of those is sagu starch which is an alternative of raw material for the production of biodegradable plastics. This research was aiming to develop a bioplastic using oxidized sago starch. In this study, we performed a physicochemical characterization of native starch, oxidized starch, and bioplastic made from starch. The analyzes performed were: percentage of carbonyl and carboxil groups, transparent gels. It was also applied a scanning electron microscopy where an irregular appearance of the starch granules size was observed. In addition, EDS microscopy allowed us to observe the simple chemistry of the granules, where the oxidized starches have a higher percentage of oxygen than native starch. In the analysis of X ray diffraction, it was observed the patterns of diffraction and the semicrystalline character of the starch. The FT-IR spectrum shows the characteristics of native and oxidized starches bands. On the other hand, the solubility tests and transparency show an advantage of bioplastic made with oxidized starch.Keywords: Starch, Sagu, Oxidized starch, Bioplastics.El uso excesivo de materiales derivados del petróleo como: combustibles, lubricantes, colorantes, disolventes, asfaltos, fibras textiles y plásticos ha generado a través del tiempo un grave problema ambiental, debido, a los largos periodos de degradación de estos materiales. Es por esto que hoy en día la investigación se centra en los plásticos ya que poseen poca vida útil, estos residuos terminan depositándose en rellenos sanitarios, océanos, lagos y demás fuentes hídricas generando la contaminación de este recurso vital para la vida, todo esto, provoca la muerte de especies animales y la desestabilización del ecosistema. La ciencia ha planteado soluciones tales como: reciclar, uso de papel y el desarrollo de materiales biodegradables siendo el almidón de sagú una alternativa como materia prima para la elaboración de este tipo de materiales. Esta investigación fue orientada a la elaboración de bioplástico utilizando como base almidón de sagú oxidado. Los estudios consisten en una caracterización fisicoquímica al almidón nativo, almidón oxidado y al bioplástico elaborado a base de almidón. Los análisis realizados fueron: porcentaje de grupos carbonilo y de grupos carboxilo, transparencia de los geles, microscopia electrónica de barrido donde se observó la apariencia irregular y los tamaños de los gránulos de almidón, además, el microscopio con EDS permitió observar las composiciones químicas simples de los gránulos, donde, los almidones oxidados tienen mayor porcentaje de oxigeno que el almidón nativo. En los análisis de difracción de rayos X se observa los patrones de difracción y el carácter semicristalino del almidón. El espectro de FT-IR muestra las bandas propias de los almidones nativos y oxidados. Por otra parte, las pruebas de solubilidad, transparencia muestran una ventaja del bioplástico elaborado con almidón oxidado.Palabras clave: Almidón, sagú, Almidón oxidado, Bioplástico

Analyzing multitarget activity landscapes using protein-ligand interaction fingerprints: interaction cliffs.

This is the original submitted version, before peer review. The final peer-reviewed version is available from ACS at http://pubs.acs.org/doi/abs/10.1021/ci500721x.Activity landscape modeling is mostly a descriptive technique that allows rationalizing continuous and discontinuous SARs. Nevertheless, the interpretation of some landscape features, especially of activity cliffs, is not straightforward. As the nature of activity cliffs depends on the ligand and the target, information regarding both should be included in the analysis. A specific way to include this information is using protein-ligand interaction fingerprints (IFPs). In this paper we report the activity landscape modeling of 507 ligand-kinase complexes (from the KLIFS database) including IFP, which facilitates the analysis and interpretation of activity cliffs. Here we introduce the structure-activity-interaction similarity (SAIS) maps that incorporate information on ligand-target contact similarity. We also introduce the concept of interaction cliffs defined as ligand-target complexes with high structural and interaction similarity but have a large potency difference of the ligands. Moreover, the information retrieved regarding the specific interaction allowed the identification of activity cliff hot spots, which help to rationalize activity cliffs from the target point of view. In general, the information provided by IFPs provides a structure-based understanding of some activity landscape features. This paper shows examples of analyses that can be carried out when IFPs are added to the activity landscape model.M-L is very grateful to CONACyT (No. 217442/312933) and the Cambridge Overseas Trust for funding. AB thanks Unilever for funding and the European Research Council for a Starting Grant (ERC-2013- StG-336159 MIXTURE). J.L.M-F. is grateful to the School of Chemistry, Department of Pharmacy of the National Autonomous University of Mexico (UNAM) for support. This work was supported by a scholarship from the Secretariat of Public Education and the Mexican government

BMD loci contribute to ethnic and developmental differences in skeletal fragility across populations: Assessment of evolutionary selection pressures

Bone mineral density (BMD) is a highly heritable trait used both for the diagnosis of osteoporosis in adults and to assess bone health in children. Ethnic differences in BMD have been documented, with markedly higher levels in individuals of African descent, which partially explain disparity in osteoporosis risk across populations. To date, 63 independent genetic variants have been associated with BMD in adults of Northern-European ancestry. Here, we demonstrate that at least 61 of these variants are predictive of BMD early in life by studying their compound effect within two multiethnic pediatric cohorts. Furthermore, we show that within these cohorts and across populations worldwide the frequency of those alleles associated with increased BMD is systematically elevated in individuals of Sub-Saharan African ancestry. The amount of differentiation in the BMD genetic scores among Sub-Saharan and non-Sub-Saharan populations together with neutrality tests, suggest that these allelic differences are compatible with the hypothesis of selective pressures acting on the genetic determinants of BMD. These findings constitute an explorative contribution to the role of selection on ethnic BMD differences and likely a new example of polygenic adaptation acting on a human trait

Genome-wide association analysis of dementia and its clinical endophenotypes reveal novel loci associated with Alzheimer's disease and three causality networks : The GR@ACE project

Introduction: Large variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways. Methods: Genome Research at Fundacio ACE (GR@ACE) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, GR@ACE series were meta-analyzed with additional genome-wide association study data sets. Results: We classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444. Discussion: The regulation of vasculature is a prominent causal component of probable AD. GR@ACE meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series

Amplified Genes May Be Overexpressed, Unchanged, or Downregulated in Cervical Cancer Cell Lines

Several copy number-altered regions (CNAs) have been identified in the genome of cervical cancer, notably, amplifications of 3q and 5p. However, the contribution of copy-number alterations to cervical carcinogenesis is unresolved because genome-wide there exists a lack of correlation between copy-number alterations and gene expression. In this study, we investigated whether CNAs in the cell lines CaLo, CaSki, HeLa, and SiHa were associated with changes in gene expression. On average, 19.2% of the cell-line genomes had CNAs. However, only 2.4% comprised minimal recurrent regions (MRRs) common to all the cell lines. Whereas 3q had limited common gains (13%), 5p was entirely duplicated recurrently. Genome-wide, only 15.6% of genes located in CNAs changed gene expression; in contrast, the rate in MRRs was up to 3 times this. Chr 5p was confirmed entirely amplified by FISH; however, maximum 33.5% of the explored genes in 5p were deregulated. In 3q, this rate was 13.4%. Even in 3q26, which had 5 MRRs and 38.7% recurrently gained SNPs, the rate was only 15.1%. Interestingly, up to 19% of deregulated genes in 5p and 73% in 3q26 were downregulated, suggesting additional factors were involved in gene repression. The deregulated genes in 3q and 5p occurred in clusters, suggesting local chromatin factors may also influence gene expression. In regions amplified discontinuously, downregulated genes increased steadily as the number of amplified SNPs increased (p<0.01, Spearman's correlation). Therefore, partial gene amplification may function in silencing gene expression. Additional genes in 1q, 3q and 5p could be involved in cervical carcinogenesis, specifically in apoptosis. These include PARP1 in 1q, TNFSF10 and ECT2 in 3q and CLPTM1L, AHRR, PDCD6, and DAP in 5p. Overall, gene expression and copy-number profiles reveal factors other than gene dosage, like epigenetic or chromatin domains, may influence gene expression within the entirely amplified genome segments

Biological processes, properties and molecular wiring diagrams of candidate low-penetrance breast cancer susceptibility genes

Background: Recent advances in whole-genome association studies (WGASs) for human cancer risk are beginning to provide the part lists of low-penetrance susceptibility genes. However, statistical analysis in these studies is complicated by the vast number of genetic variants examined and the weak effects observed, as a result of which constraints must be incorporated into the study design and analytical approach. In this scenario, biological attributes beyond the adjusted statistics generally receive little attention and, more importantly, the fundamental biological characteristics of low-penetrance susceptibility genes have yet to be determined. Methods: We applied an integrative approach for identifying candidate low-penetrance breast cancer susceptibility genes, their characteristics and molecular networks through the analysis of diverse sources of biological evidence. Results: First, examination of the distribution of Gene Ontology terms in ordered WGAS results identified asymmetrical distribution of Cell Communication and Cell Death processes linked to risk. Second, analysis of 11 different types of molecular or functional relationships in genomic and proteomic data sets defined the 'omic' properties of candidate genes: i/ differential expression in tumors relative to normal tissue; ii/ somatic genomic copy number changes correlating with gene expression levels; iii/ differentially expressed across age at diagnosis; and iv/ expression changes after BRCA1 perturbation. Finally, network modeling of the effects of variants on germline gene expression showed higher connectivity than expected by chance between novel candidates and with known susceptibility genes, which supports functional relationships and provides mechanistic hypotheses of risk. Conclusion: This study proposes that cell communication and cell death are major biological processes perturbed in risk of breast cancer conferred by low-penetrance variants, and defines the common omic properties, molecular interactions and possible functional effects of candidate genes and proteins

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms