Vanadate Retention by Iron and Manganese Oxides.

Anthropogenic emissions of vanadium (V) into terrestrial and aquatic surface systems now match those of geogenic processes, and yet, the geochemistry of vanadium is poorly described in comparison to other comparable contaminants like arsenic. In oxic systems, V is present as an oxyanion with a +5 formal charge on the V center, typically described as H x VO4 (3-x)-, but also here as V(V). Iron (Fe) and manganese (Mn) (oxy)hydroxides represent key mineral phases in the cycling of V(V) at the solid-solution interface, and yet, fundamental descriptions of these surface-processes are not available. Here, we utilize extended X-ray absorption fine structure (EXAFS) and thermodynamic calculations to compare the surface complexation of V(V) by the common Fe and Mn mineral phases ferrihydrite, hematite, goethite, birnessite, and pyrolusite at pH 7. Inner-sphere V(V) complexes were detected on all phases, with mononuclear V(V) species dominating the adsorbed species distribution. Our results demonstrate that V(V) adsorption is exergonic for a variety of surfaces with differing amounts of terminal -OH groups and metal-O bond saturations, implicating the conjunctive role of varied mineral surfaces in controlling the mobility and fate of V(V) in terrestrial and aquatic systems.

Cetoacidosis diabética euglucémica en un estado perioperatorio por resección de quiste epidermoide del ángulo pontocerebeloso / Euglycemic diabetic ketoacidosis in perioperative state due to resection of the epidermoid cyst of the pontocerebellar angle / Cetoacidose euglicêmica diabética em estado perioperatório devido à ressecção de cisto epidermóide do ângulo pontocerebelar

Resumen: La cetoacidosis diabética es una complicación aguda de la diabetes mellitus, caracterizada por acidosis metabólica con un aumento de la brecha aniónica y evidencia de cuerpos cetónicos en sangre u orina. En la mayor parte de los casos se presenta con hiperglucemia. La cetoacidosis diabética euglucémica se define por la tríada de glucosa con valores menores de 200 mg/dL, acidosis metabólica con anión gap elevado y cetonemia. Los factores asociados con esta entidad son embarazo, tratamiento con SGLT2, disminución da la ingesta calórica, enfermedades hepáticas, ingesta crónica de alcohol, uso de insulina previo a la hospitalización, sepsis, pancreatitis, aumento de las hormonas contrarreguladoras y estados perioperatorios. La base del tratamiento consiste en la corrección rápida de la deshidratación con fluidos intravenosos así como el uso de goteo de insulina junto con una solución que contiene dextrosa hasta que la brecha aniónica y los niveles de bicarbonato se normalicen. En este artículo se reporta el caso de una paciente que ingresa a UCI en el periodo perioperatorio inmediato.

Abstract: Diabetic ketoacidosis is an acute complication of diabetes, characterized by metabolic acidosis with an increase in the values of anion gap and evidence of ketone bodies in blood or urine. In most cases, it is present with hyperglycemia. Euglycemic diabetic ketoacidosis is defined by the triad of glucose with values < than 200 mg/dL, metabolic acidosis with high anion gap and ketonemia. The factors associated with this entity are pregnancy, treatment with SGLT2, decrease in caloric intake, liver disease, chronic alcohol intake, use of insulin prior to hospitalization, sepsis, pancreatitis, increase in counter-regulatory hormones and perioperative states. The basis of the treatment is the rapid correction of dehydration with intravenous fluids, as well as the use of insulin drip along with a solution containing dextrose until the anion gap, and bicarbonate levels normalize. In this article, a case of a patient admitted to the ICU in the immediate perioperative period is reported.

Resumo: A cetoacidose diabética é uma complicação aguda do diabetes mellitus, caracterizada por acidose metabólica com aumento do gap aniônico e evidência de corpos cetônicos no sangue ou na urina. Na maioria dos casos está presente com hiperglicemia. A cetoacidose diabética euglicêmica é definida pela tríade glicêmica com valores inferiores a 200 mg/dL, acidose metabólica com amplo ânion Gap e cetonemia. Os fatores associados a essa entidade são gravidez, tratamento com SGLT2, diminuição da ingestão calórica, doença hepática, ingestão crônica de álcool, uso de insulina antes da hospitalização, sepse, pancreatite, aumento de hormônios contra-regulatórios e estados perioperatórios. A base do tratamento consiste na correção rápida da desidratação com fluidos intravenosos, bem como no uso de infusāo de insulina, juntamente com uma solução contendo dextrose até o hiato aniônico e os níveis de bicarbonato voltarem ao normal. Neste artigo, é relatado o caso de um paciente admitido na UTI no período perioperatório imediato.

Genomic epidemiology of the commercially important pathogen Renibacterium salmoninarum within the Chilean salmon industry.

Renibacterium salmoninarum is the causative agent of bacterial kidney disease (BKD), which is a commercially important disease of farmed salmonids. Typing by conventional methods provides limited information on the evolution and spread of this pathogen, as there is a low level of standing variation within the R. salmoninarum population. Here, we apply whole-genome sequencing to 42 R. salmoninarum isolates from Chile, primarily from salmon farms, in order to understand the epidemiology of BKD in this country. The patterns of genomic variation are consistent with multiple introductions to Chile, followed by rapid dissemination over a 30 year period. The estimated dates of introduction broadly coincide with major events in the development of the Chilean aquaculture industry. We find evidence for significant barriers to transmission of BKD in the Chilean salmon production chain that may also be explained by previously undescribed signals of host tropism in R. salmoninarum. Understanding the genomic epidemiology of BKD can inform disease intervention and improve sustainability of the economically important salmon industry. This article contains data hosted by Microreact.

[Involvement of matrix metalloproteinases in acute coronary syndrome (ACS)]. / Participación de las metaloproteinasas de matriz en el síndrome isquémico coronario agudo (SICA).

Matrix metalloproteinases (MMP) are enzymes that degrade extracellular matrix (ECM) proteins and regulate both their accumulation and composition. The MMP are involved in the atherosclerotic process since they contribute to the formation of the plaque and its subsequent rupture. This last step triggers the myocardial ischemia that will be clinically reflected as an acute coronary syndrome (ACS). Thus, MMP activity is a key to whether ACS develops or not. With an elevated transcription rate of the genes that codify these proteinases comes a higher enzymatic activity. This explains that if a polymorphism in the mentioned genes modifies transcription, there could be a predisposition to developing ACS. Several studies reveal that certain genetic variations in MMP-1, -2, -3, -7, -8, -9, -12, and -14 have an important role either as risk factors or as protective factors for the expression of ACS.

Morphology-based hypothesis testing in discrete random fields: a non-parametric method to address the multiple-comparison problem in neuroimaging.

A new method for detecting activations in random fields, which may be useful for addressing the issue of multiple comparisons in neuroimaging, is presented. This method is based on some constructs of mathematical morphology--specifically, morphological erosions and dilations--that enable the detection of active regions in random fields possessing moderate activation levels and relatively large spatial extension, which may not be detected by the standard methods that control the family-wise error rate. The method presented here permits an appropriate control of the false positive errors, without having to adjust any threshold values, other than the significance level. The method is easily adapted to permutation-based procedures (with the usual restrictions), and therefore does not require strong assumptions about the distribution and spatio-temporal correlation structure of the data. Some examples of applications to synthetic data, including realistic fMRI simulations, as well as to real fMRI and electroencephalographic data are presented, illustrating the power of the presented technique. Comparisons with other methods that combine voxel intensity and cluster size, as well as some extensions of the method presented here based on their basic ideas are presented as well.

Morphology-based hypothesis testing in discrete random fields: a non-parametric method to address the multiple-comparison problem in neuroimaging.

A new method for detecting activations in random fields, which may be useful for addressing the issue of multiple comparisons in neuroimaging, is presented. This method is based on some constructs of mathematical morphology - specifically, morphological erosions and dilations - that enable the detection of active regions in random fields possessing moderate activation levels and relatively large spatial extension, which may not be detected by the standard methods that control the family-wise error rate. The method presented here permits an appropriate control of the false positive errors, without having to adjust any threshold values, other than the significance level. The method is easily adapted to permutation-based procedures (with the usual restrictions), and therefore does not require strong assumptions about the distribution and spatio-temporal correlation structure of the data. Some examples of applications to synthetic data, including realistic fMRI simulations, as well as to real fMRI and electroencephalographic data are presented, illustrating the power of the presented technique. Comparisons with other methods that combine voxel intensity and cluster size, as well as some extensions of the method presented here based on their basic ideas are presented as well.

DNA extraction from formalin-fixed laryngeal biopsies: Comparison of techniques.

CONCLUSION: PCR-quality DNA could be extracted from formalin-fixed paraffin-embedded (FFPE) samples with amplicons of at least 390 bp. Paraffin removal was not a necessary step. Proteinase K digestion was as efficient as the commercial kit for DNA extraction with a lower cost. OBJECTIVES: To compare different DNA extraction protocols for FFPE samples and to describe the suitability of the extracted DNA for PCR reactions. METHODS: For deparaffinization the following techniques were compared: alkaline heat, xylene, and no removal. For DNA extraction, proteinase K digestion and organic extraction were compared. A commercial extraction kit was included as standard. DNA quality was assessed by PCR amplification of the HFE gene, for amplicons of 208 and 390 bp. RESULTS: Extraction with the commercial kit and proteinase K digestion were more efficient than other techniques, with no statistical difference between them for both amplicons. The proteinase K digestion buffer had a cost of U$ 0.2 per sample and the commercial kit of U$7 per sample.

Microcystis toxigenic strains in urban lakes: a case of study in Mexico City.

Microcystis is a bloom-forming, common cyanobacterium in urban lakes of Mexico City. To assess the presence of potentially cyanotoxin-producing Microcystis, molecular techniques were applied and acute toxicity bioassays were performed with Daphnia magna neonates exposed to cyanobacterial crude extracts. Toxigenic potential of isolated strains was inferred by amplifying the mcyA-Cd genes and their identity as Microcystis was confirmed through the 16S rDNA and phycocyanin operon amplification. Microcystins synthesized under culture conditions were quantified through ELISA. The acute toxicity bioassays revealed that mortality was independent from the cyanotoxin concentration in some strains; this suggests the presence of other metabolites (different from microcystins) that also exerted an important biological effect. Isolated strains had the mcyA-Cd gene and most of them produced variable amounts of microcystins in the culture conditions used, confirming their toxigenic potential. Results warn about possible toxic effect risks for aquatic biota, neighboring areas, visitors and users of these sites, due to the constant presence of these blooms in the studied water bodies.

Uso tradicional y actual de spirulina sp. (arthrospira sp.) / Traditional and present use of spirulina sp. (arthrospira sp.)

Spirulina sp. (Arthrospira sp.) es una cianobacteria filamentosa no diferenciada, habitante de lagos alcalinos, que se cultiva para consumo humano debido a su contenido nutricional. En México, el consumo de esta cianobacteria se remonta a tiempos prehispánicos, cuando era conocida como tecuitlatl, siendo conocida como dihé por las tribus nativas de la región del lago de Chad, en Africa. En los últimos años se le han atribuido diversos efectos positivos en el tratamiento de algunos tipos de alergias, anemia, cáncer, enfermedades virales y cardiovasculares. Muchas de sus propiedades son consecuencia de la presencia de pigmentos como las ficobiliproteínas y los carotenoides, así como de otros compuestos como polisacáridos, ácidos grasos (destacando el ácido gama linoleico), proteínas, vitaminas y minerales. Las propiedades y aplicaciones de este organismo hacen de él un alimento promotor de la salud o nutracéutico

Detection, isolation, and characterization of exopolysaccharide produced by a strain of Phormidium 94a isolated from an arid zone of Mexico.

Phormidium 94a, a cyanobacteria that produces extracellular polymeric substances (EPS), was isolated from arid soils of Mexico. Microscopic localization, using histochemical techniques like the Toluidine blue technique, was done in order to demonstrate the presence of EPS. Acetone was added to precipitate the EPS. In this study we characterized the EPS by GC, HPLC, and IR techniques. The highest fraction of EPS had a molecular weight of 2000 kDa. The sugar composition was galactose, mannose, galacturonic acid, arabinose, and ribose in the three main fractions, and the sugar ratio found was different in each fraction. The low EPS concentrations had a Newtonian behavior, when the concentrations were increased, the behavior changed to pseudoplastic. The EPS rheulogical behavior is similar to low viscosity arabic gum. Also, it was found that an increase in viscosity occurred at longer hydration time. More rheological and toxicological studies are required in order to analyze its possible application in food industries.