Hypothyroidism in ruminants

La glándula tiroides está presente en todos los vertebrados y es única entre las glándulas endocrinas en que almacena sus productos de secreción (hormonas tiroidales) extracelularmente. Estas hormonas juegan un papel indispensable en una variedad de reacciones bioquímicas en tejidos periféricos como el músculo esquelético, cardíaco, el hígado y el riñón los que colectivamente controlan la actividad metabólica basal del organismo. A pesar de que muchos procesos fisiológicos en rumiantes requieren una actividad normal de la glándula tiroides, generalmente se ha resaltado su rol principalmente en la fisiología reproductiva. Sin embargo, en la mayoría de la literatura actual, la síntesis y acciones de las hormonas tiroidales en la fisiología de los rumiantes se ha extrapolado del conocimiento extenso que se tiene en la especie canina y felina. Por lo tanto, este trabajo pretende entregar información actualizada sobre la fisiología endocrina de la glándula tiroides en los rumiantes, enfatizando su rol en el bovino y ovino y las causas mas comunes de hipotiroidismo clínico en los rumiantes domésticos.The thyroid gland is present in all vertebrates and it is unique among endocrine glands in that it stores its secretory products (the thyroid hormones) extracellularly. These hormones play an indispensable role in a variety of biochemical reactions at the level of peripheral tissues such as the skeletal and heart muscle, the liver and the kidney which collectively control the basal metabolic activity of the organism. Although many physiologic processes in ruminant require a normal activity of the thyroid gland, their role has generally been emphasized in the reproductive physiology. However, in most of the current literature, the synthesis and mechanism of action of the thyroid hormones in the ruminant physiology have been extrapolated of the extensive knowledge that we have in the canine and feline species. This work seeks to give up-to-date information on the endocrine physiology of the ruminant thyroid gland, emphasizing its role in the bovine and ovine species and the more common causes of clinic hypothyroidism in domestic ruminants

Influence of Nitrogen Fertilization on the Quality and Quantity of Streamflow from a Forested Watershed

This project was designed to determine the effects of nitrogen fertilization on the quality and quantity of streamflow eminating from an eastern hardwood forest watershed. A 40.67 ha watershed, located in mountainous eastern Kentucky, was aerially fertilized in late April 1975. The forest stand was principally oak, hickory, and yellow poplar, 50 - 55 years of age and in a relatively undisturbed condition. A helicopter applied anunonium nitrate at a rate of 504 kg/ha. Because a large part of applied nitrogen fertilizer ends up in the highly mobile nitrate nitrogen.form, this is the principal ion monitored in this study. No effort was made to avoid live streams during application and, consequently, very high levels of nitrate nitrogen were detected (640 mg/1) in streamfiow within the watershed. Levels potentially toxic to humans and animals persisted in the streamflow for several days following application. Although elevated concentrations of nitrate nitrogen persisted in streamflow leaving the watershed over a two year period no algal blooms or excessive growth of aquatic plants were noted. Rather high concentrations of nitrate nitrogen were found in the soils of the watershed, with greatest concentrations in the surface layer (0 - 5 cm), intermediate amounts at 15 - 20 cm, and the lowest concentrations at the 41 - 46 cm depth. The effects of the fertilizer application on soils persisted less than one year in the 0 - 46 cm depth sampled. Analysis of streamf1ow records indicated a reduction in water yield the first and second growing seasons after treatment. Gross budgeting of nitrate nitrogen inputs vs. outputs suggests this anion accumulates on these relatively undisturbed watersheds at an annual rate of 3 to 5 kg/ha

Actividad de glutation peroxidasa (GSH-Px) en sangre de bovinos a pastoreo de la IX Región, Chile y su relación con la concentración de selenio en el forraje

Con el objeto de determinar la actividad sanguínea de glutatión peroxidasa (GSH-Px; E.C. 1.11.1.9) en bovinos lecheros de la IX Región de la Araucanía (38º LS y 71º LO), Chile, y establecer su eventual asociación con el contenido de Se en el forraje, durante el otoño y la primavera de 1999 se tomaron muestras de forraje de las praderas y de sangre en grupos de vacas en inicio de lactancia y vaquillas en 12 predios lecheros. Se midió la concentración de Se en el forraje empleando la técnica de espectroscopía de plasma acoplado inductivamente con detector de masas (ICP-MS) y la actividad sanguínea de GSH-Px mediante una técnica cinética compuesta NADPH-dependiente. La concentración de Se del forraje fue 0.03±0.02 ppm, donde un 83% presentó valores deficitarios (0.05). Se encontró un 20% de los grupos analizados con valores deficitarios (0.05). Heifers showed a lower activity for GSH-Px than cows in both periods (p<0.05). Twenty percent of the animals showed a low activity of GSH-Px (below 60 U/g Hb), meaning a Se deficiency in the animals. There was a relation between the content of Se in forage and the blood activity of GSH-Px in heifers (r= 0.74; p<0.05). Accordingly, the content of Se in most of the forage produced in the dairy cattle area from the IXth Region, Chile is below the nutritional requirements for grazing dairy cattle and nutritional metabolic deficiencies of Se are present in dairy herds according to blood activity of GSH-Px. Heifers are mostly affecte

Engineered living hydrogels for robust biocatalysis in pure organic solvents

Engineered living hydrogels that can protect cells from harsh environments have achieved preliminary successes in biomedicine and environmental remediation. However, their biocatalytic applications in pure organic solvents have not been explored. Here, living hydrogels were engineered by integrating genetically modified Escherichia coli cells into alginate hydrogels for robust biocatalysis in pure organic solvents. The biocompatible hydrogels could not only support cell growth and diminish cell escape but could also act as protective matrices to improve organic solvent tolerance, thereby prolonging catalytic activity of whole-cell biocatalysts. Moreover, the influence of hydrogel microenvironments on biocatalytic efficiency was thoroughly investigated. Importantly, the versatility of engineered living hydrogels paves the way to achieve robust biocatalytic efficiency in a variety of pure organic co-solvents. Overall, we are able to engineer living hydrogels for regio-selective synthesis in pure organic solvents, which may be particularly useful for the innovation of living hydrogels in biocatalysis

Mixotrophic growth under micro-oxic conditions in the purple sulfur bacterium "Thiodictyon syntrophicum"

The microbial ecosystem of the meromictic Lake Cadagno (Ticino, Swiss Alps) has been studied intensively in order to understand structure and functioning of the anoxygenic phototrophic sulfur bacteria community living in the chemocline. It has been found that the purple sulfur bacterium “Thiodictyon syntrophicum” strain Cad16T, belonging to the Chromatiaceae, fixes around 26% of all bulk inorganic carbon in the chemocline, both during day and night. With this study, we elucidated for the first time the mode of carbon fixation of str. Cad16T under micro-oxic conditions with a combination of long-term monitoring of key physicochemical parameters with CTD, 14C-incorporation experiments and quantitative proteomics using in-situ dialysis bag incubations of str. Cad16T cultures. Regular vertical CTD profiling during the study period in summer 2017 revealed that the chemocline sank from 12 to 14 m which was accompanied by a bloom of cyanobacteria and the subsequent oxygenation of the deeper water column. Sampling was performed both day and night. CO2 assimilation rates were higher during the light period compared to those in the dark, both in the chemocline population and in the incubated cultures. The relative change in the proteome between day and night (663 quantified proteins) comprised only 1% of all proteins encoded in str. Cad16T. Oxidative respiration pathways were upregulated at light, whereas stress-related mechanisms prevailed during the night. These results indicate that low light availability and the co-occurring oxygenation of the chemocline induced mixotrophic growth in str. Cad16T. Our study thereby helps to further understand the consequences micro-oxic conditions for phototrophic sulfur oxidizing bacteria. The complete proteome data have been deposited to the ProteomeXchange database with identifier PXD010641

A Weighted Estimate for the Square Function on the Unit Ball in \C^n

We show that the Lusin area integral or the square function on the unit ball of \C^n, regarded as an operator in weighted space $L^2(w)$ has a linear bound in terms of the invariant $A_2$ characteristic of the weight. We show a dimension-free estimate for the ``area-integral'' associated to the weighted $L^2(w)$ norm of the square function. We prove the equivalence of the classical and the invariant $A_2$ classes.Comment: 11 pages, to appear in Arkiv for Matemati

Complete genome sequence of “Thiodictyon syntrophicum” sp. nov. strain Cad16T, a photolithoautotrophic purple sulfur bacterium isolated from the alpine meromictic Lake Cadagno

"Thiodictyon syntrophicum" sp. nov. strain Cad16T is a photoautotrophic purple sulfur bacterium belonging to the family of Chromatiaceae in the class of Gammaproteobacteria. The type strain Cad16T was isolated from the chemocline of the alpine meromictic Lake Cadagno in Switzerland. Strain Cad16T represents a key species within this sulfur-driven bacterial ecosystem with respect to carbon fixation. The 7.74-Mbp genome of strain Cad16T has been sequenced and annotated. It encodes 6237 predicted protein sequences and 59 RNA sequences. Phylogenetic comparison based on 16S rRNA revealed that Thiodictyon elegans strain DSM 232T the most closely related species. Genes involved in sulfur oxidation, central carbon metabolism and transmembrane transport were found. Noteworthy, clusters of genes encoding the photosynthetic machinery and pigment biosynthesis are found on the 0.48 Mb plasmid pTs485. We provide a detailed insight into the Cad16T genome and analyze it in the context of the microbial ecosystem of Lake Cadagno

Complete genome sequence of “Thiodictyon syntrophicum” sp. nov. strain Cad16T, a photolithoautotrophic purple sulfur bacterium isolated from the alpine meromictic Lake Cadagno

"Thiodictyon syntrophicum" sp. nov. strain Cad16T is a photoautotrophic purple sulfur bacterium belonging to the family of Chromatiaceae in the class of Gammaproteobacteria. The type strain Cad16T was isolated from the chemocline of the alpine meromictic Lake Cadagno in Switzerland. Strain Cad16T represents a key species within this sulfur-driven bacterial ecosystem with respect to carbon fixation. The 7.74-Mbp genome of strain Cad16T has been sequenced and annotated. It encodes 6237 predicted protein sequences and 59 RNA sequences. Phylogenetic comparison based on 16S rRNA revealed that Thiodictyon elegans strain DSM 232T the most closely related species. Genes involved in sulfur oxidation, central carbon metabolism and transmembrane transport were found. Noteworthy, clusters of genes encoding the photosynthetic machinery and pigment biosynthesis are found on the 0.48 Mb plasmid pTs485. We provide a detailed insight into the Cad16T genome and analyze it in the context of the microbial ecosystem of Lake Cadagno

Complete genome sequence of “Thiodictyon syntrophicum” sp. nov. strain Cad16T, a photolithoautotrophic purple sulfur bacterium isolated from the alpine meromictic Lake Cadagno

"Thiodictyon syntrophicum" sp. nov. strain Cad16T is a photoautotrophic purple sulfur bacterium belonging to the family of Chromatiaceae in the class of Gammaproteobacteria. The type strain Cad16T was isolated from the chemocline of the alpine meromictic Lake Cadagno in Switzerland. Strain Cad16T represents a key species within this sulfur-driven bacterial ecosystem with respect to carbon fixation. The 7.74-Mbp genome of strain Cad16T has been sequenced and annotated. It encodes 6237 predicted protein sequences and 59 RNA sequences. Phylogenetic comparison based on 16S rRNA revealed that Thiodictyon elegans strain DSM 232T the most closely related species. Genes involved in sulfur oxidation, central carbon metabolism and transmembrane transport were found. Noteworthy, clusters of genes encoding the photosynthetic machinery and pigment biosynthesis are found on the 0.48 Mb plasmid pTs485. We provide a detailed insight into the Cad16T genome and analyze it in the context of the microbial ecosystem of Lake Cadagno

A Renormalization Group for Hamiltonians: Numerical Results

We describe a renormalization group transformation that is related to the breakup of golden invariant tori in Hamiltonian systems with two degrees of freedom. This transformation applies to a large class of Hamiltonians, is conceptually simple, and allows for accurate numerical computations. In a numerical implementation, we find a nontrivial fixed point and determine the corresponding critical index and scaling. Our computed values for various universal constants are in good agreement with existing data for area-preserving maps. We also discuss the flow associated with the nontrivial fixed point.Comment: 11 Pages, 2 Figures. For future updates, check ftp://ftp.ma.utexas.edu/pub/papers/koch