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

Bioscorodite: biological crystallization of scorodite for arsenic removal

The use of arsenic is banned for most applications, leading to its accumulation as arsenic trioxide and ferric arsenate sludge. The aim of this thesis was to develop a controlled process for biological crystallization of scorodite from metallurgical streams. In this thesis, the proof of principle, reactor selection and operational conditions of bioscorodite crystallization were studied. The results from this thesis resulted in the ARSENOTEQTM process, currently commercialized by Paques B.V. (Balk, The Netherlands). The bioscorodite process in practice occurs in a continuous airlift reactor at pH </p

Biotechnology based processes for arsenic removal

The regulations for arsenic control have become strict. Therefore, better technologies to remove arsenic from bleeds and effluents are desired. In addition, no single solution is suitable for all cases. The properties of the process streams and the storage facilities are major factors determining the selection of a certain technology. In this paper, two technologies are described. What these technologies have in common is that they are based on high-rate engineered bioreactors that allow optimal control, efficient resource use, and predictable and reliable process performance. One technology (Arsenoteq) converts arsenic to corodite, which is most suitable for storage under oxidising conditions. The other technology (Thioteq) operates under reducing conditions and produces arsenic sulphide (As2S3, orpiment) with 61 mass% arsenic. The first technology is suitable for medium to high (> 1000 mg/L) concentrations of arsenic in acidic process streams, whereas the latter is ideal for effluent treatment up to <5000 mg/L of arsenic. The residual arsenic concentration that can be obtained with the latter method is <0.1 mg/L

Bioscorodite crystallization for arsenic removal

In the bio-scorodite process, arsenic is precipitated as crystalline iron arsenate, i.e. scorodite (FeAsO4·2H2O). This is a more economic and more environmentally friendly method for arsenic immobilization than the chemical production of iron- or calcium arsenate, as fewer chemicals are needed. Moreover, scorodite is an attractive medium for arsenic control and immobilization because it is stable, compact and has a very low solubility. Therefore it is regarded as the most ideal form for long-term arsenic storage. We have demonstrated that bio-crystallization of arsenic into scorodite crystals is possible with the aid of microorganisms. The operational conditions of the bio-scorodite process allow for a fast growth of the microorganisms and facilitate the crystallization of scorodite, avoiding the precipitation of other iron oxides or amorphous iron arsenates. The bio-scorodite process brings several advantages compared to chemical crystallization such as the lower required temperature (70°C), the control of supersaturation by biological oxidation and no need for crystal parents or seeds to begin the crystallization. Arsenic concentrations are removed to ppm level with starting concentrations ranging from 1000 to 2000 mg L-1. The produced bioscorodite crystals are very similar to the scorodite mineral found in nature. By control of the iron feed and the pH, the production of other iron precipitates is avoided. The latter facilitates easy separation of the solid product. Based on their highly crystalline nature, the biogenic scorodite crystals seem very suitable for safe disposal. At present the research has started with the continuous production of scorodite in bioreactors. The follow-up challenges are focused on the selection of a suitable reactor configuration

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

Kinetics of ferrous iron oxidation by batch and continuous cultures of thermoacidophilic Archaea at extremely low pH of 1.1–1.3

The extreme acid conditions required for scorodite (FeAsO4·2H2O) biomineralization (pH below 1.3) are suboptimal for growth of most thermoacidophilic Archaea. With the objective to develop a continuous process suitable for biomineral production, this research focuses on growth kinetics of thermoacidophilic Archaea at low pH conditions. Ferrous iron oxidation rates were determined in batch-cultures at pH 1.3 and a temperature of 75°C for Acidianus sulfidivorans, Metallosphaera prunea and a mixed Sulfolobus culture. Ferrous iron and CO2 in air were added as sole energy and carbon source. The highest growth rate (0.066 h-1) was found with the mixed Sulfolobus culture. Therefore, this culture was selected for further experiments. Growth was not stimulated by increase of the CO2 concentration or by addition of sulphur as an additional energy source. In a CSTR operated at the suboptimal pH of 1.1, the maximum specific growth rate of the mixed culture was 0.022 h-1, with ferrous iron oxidation rates of 1.5 g L-1 d-1. Compared to pH 1.3, growth rates were strongly reduced but the ferrous iron oxidation rate remained unaffected. Influent ferrous iron concentrations above 6 g L-1 caused instability of Fe2+ oxidation, probably due to product (Fe3+) inhibition. Ferric-containing, nano-sized precipitates of K-jarosite were found on the cell surface. Continuous cultivation stimulated the formation of an exopolysaccharide-like substance. This indicates that biofilm formation may provide a means of biomass retention. Our findings showed that stable continuous cultivation of a mixed iron-oxidizing culture is feasible at the extreme conditions required for continuous biomineral formation

Effect of a selenium-deficient diet on blood values of T3 and T4 in cows

Pastures in the south of Chile have been shown to be selenium deficient, and as selenium is a component of deiodinase type 1, which is necessary for the synthesis of triiodothyronine (T3) at peripheral levels, the effect of selenium deficiency on the blood concentration of theses hormones in cows was studied. Twelve pregnant Friesian cows were randomly allocated into two homogeneous groups of six animals each-selenium supplemented and selenium deficient. The selenium deficient diet consisted of 11.5 kg of hay, 500 g of soya bran, 150 g of mineral mix (without selenium), 500 g of fat for animal feeding, and was given from day 15 of lactation until the end of the study. A commercial concentrate (Cosetan) and urea was also given according to lactation requirements (up to 5 kg and up to 120 g, respectively). The selenium content was 0.05 ppm of dry matter (equivalent to 18% of the daily requirements). The supplemented group was injected subcutaneously with 1 mg Se/kg, using the commercial product Deposel (1 ml/50kg). Blood samples were obtained by coccygeous vein venepuncture before supplementation (prepartum basal values) and thereafter every 15 days. GSH-Px activity in plasma was measured using a HITACHI 4020 spectrophotometer. Serum T3 and thyroxine (T4) concentrations were measured by electrochemiluminiscence. ANOVA, Tuckey test and Student's t-test were used to establish the significance of the intra group differences, with p = < 0.05 being considered significant. There were no significant differences in blood values of T4 in either the supplemented or non-supplemented groups during pregnancy and lactation. However the blood values of T4 decreased significantly (p = < 0.05) during days 30-60 of lactation to values below the reference range. The T3 serum concentrations in the supplemented group of cows were significantly lower (p = < 0.05) at 60, 90 and 150 days of lactation than cows that had been supplemented with selenium

Chemical composition and antibacterial and antioxidant activity of a citrus essential oil and its fractions

ABSTRACT Essential oils (EOs) from Citrus are the main by-product of Citrus-processing industries. In addition to food/beverage and cosmetic applications, citrus EOs could also potentially be used as an alternative to antibiotics in food-producing animals. A commercial citrus EO—Brazilian Orange Terpenes (BOT)—was fractionated by vacuum fractional distillation to separate BOT into various fractions: F1, F2, F3, and F4. Next, the chemical composition and biological activities of BOT and its fractions were characterized. Results showed the three first fractions had a high relative amount of limonene (≥10.86), even higher than the whole BOT. Conversely, F4 presented a larger relative amount of BOT’s minor compounds (carvone, cis-carveol, trans-carveol, cis-p-Mentha-2,8-dien-1-ol, and trans-p-Mentha-2,8-dien-1-ol) and a very low relative amount of limonene (0.08–0.13). Antibacterial activity results showed F4 was the only fraction exhibiting this activity, which was selective and higher activity on a pathogenic bacterium (E. coli) than on a beneficial bacterium (Lactobacillus sp.). However, F4 activity was lower than BOT. Similarly, F4 displayed the highest antioxidant activity among fractions (equivalent to BOT). These results indicated that probably those minor compounds that detected in F4 would be more involved in conferring the biological activities for this fraction and consequently for the whole BOT, instead of the major compound, limonene, playing this role exclusively

Oral Melanoacanthoma And Oral Melanotic Macule: A Report Of 8 Cases, Review Of The Literature, And Immunohistochemical Analysis

Oral melanoacanthoma (MA) is a rare, benign pigmented lesion, similar to cutaneous MA, characterized by hyperplasia of spinous keratinocytes and dendritic melanocytes. The pathogenesis of oral MA remains uncertain, although its clinical behavior is suggestive of a reactive origin. The most common intraoral sites are the buccal mucosa, lip, palate and gingiva. The average age of presentation is 28 years, mainly in blacks, with a strong female predilection. The oral melanotic macule (MM) is a small, well-circumscribed brown-to-black macule that occurs on the lips and mucous membranes. The etiology is not clear and it may represent a physiologic or reactive process. The average age of presentation is 43 years, with a female predilection. A biopsy is recommended to distinguish these lesions from each other and from other oral melanocytic lesions. We depict four cases each of oral MA and MM, affecting Caucasian and Latin American mestizo patients. The clinicopathological features of these cases reflect its ample spectrum, and to the best of our knowledge, it is the first example of oral MA affecting a Caucasian boy reported in the English literature. Therefore oral MA and MM should be considered in the differential diagnosis of pigmented lesions in the oral mucosa in these populations. © Medicina Oral.125E374E379Mishima, Y., Pinkus, H., Benign mixed tumor of melanocytes and malpighian cells. Melanoacanthoma: Its relationship to Bloch's benign non-nevoid melanoepithelioma (1960) Arch Dermatol, 81, pp. 539-550Buchner, A., Merrell, P.W., Carpenter, W.M., Relative frequency of solitary melanocytic lesions of the oral mucosa (2004) J Oral Pathol Med, 33, pp. 550-557Wright, J.M., Binnie, W.H., Byrd, D.L., Dunsworth, A.R., Intraoral melanoacanthomas (1983) J Periodontol, 54, pp. 107-111Buchner, A., Merrell, P., Hanson, L., Leider, A., Melanocytic hyperplasia of the oral mucosa (1991) Oral Surg, Oral Med Oral Pathol, 71, pp. 58-62Wright, J.M., Intraoral melanoacanthoma: A reactive melanocytic hyperplasia. Case report (1988) J Periodontol, 59, pp. 53-55Tomich, C., Zunt, S.L., Melanoacanthosis (melanoacanthoma) of the oral mucosa (1990) J Dermatol Surg Oncol, 16, pp. 231-236Contreras, E., Carlos, R., Oral melanoacanthosis (melanoachantoma): Report of a case and review of the literature (2005) Med Oral Patol Oral Cir Bucal, 10 (1), pp. 11-12,9-11Fornatora, M.L., Reich, R.F., Haber, S., Solomon, F., Freedman, P.D., Oral melanoacanthomas: A report of 10 cases, review of the literature, and immunohistochemical analysis for HMB-45 reactivity (2003) Am J Dermatopathol, 25, pp. 12-15Matsuoka, L.Y., Glasser, S., Barsky, S., Melanoacanthoma of the lip (1979) Arch Dermatol, 115, pp. 1116-1117Goode, R.K., Crawford, B.E., Callihan, M.D., Neville, B.W., Oral melanoacanthoma. Review of the literature and report of ten cases (1983) Oral Surg Oral Med Oral Pathol, 56, pp. 622-628Scheneider, L.C., Mesa, M.L., Haber, S.M., Melanoacanthoma of the oral mucosa (1981) Oral Surg Oral Med Oral Pathol, 52, pp. 284-287Fatahzadeh, M., Sirois, D.A., Multiple intraoral melanoacanthomas: A case report with unusual findings (2002) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 94, pp. 54-56Ho, K.K., Dervan, P., O'Loughlin, S., Powell, F.C., Labial melanotic macule: A clinical, histopathologic, and ultrastructural study (1993) J Am Acad of Dermatol, 28, pp. 33-39Sexton, F.M., Maize, J.C., Melanotic macules and melanoacanthomas of the lip. A comparative study with census of the basal melanocyte population (1987) Am J Dermatopathol, 9, pp. 438-444Horlick, H.P., Walther, R.R., Zegarelli, D.J., Silvers, D.N., Eliezri, Y.D., Mucosal melanotic macule, reactive type: A simulation of melanoma (1988) J Am Acad Dermatol, 19, pp. 786-791Buchner, A., Hansen, L.S., Pigmented nevi of the oral mucosa: A clinicopathologic study of 32 new cases and review of 75 cases from the literature: Part I. A clinicopathologic study of 32 new cases (1979) Oral Surg Oral Med Oral Pathol, 48, pp. 131-142Barker, B.F., Carpenter, W.M., Daniels, T.E., Kahn, M.A., Leider, A.S., Lozada-Nur, F., (1997) Oral mucosal melanomas: The WESTOP Banff workshop proceedings, 83, pp. 672-679. , Western Society of Teachers of Oral Pathology. Oral Surg Oral Med Oral Pathol Oral Radiol EndodBarrett, A.W., Raja, A.M., The immunohistochemical identification of human oral mucosal melanocytes (1997) Arch Oral Biol, 42, pp. 77-8

Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}=2.76 TeV

The elliptic, $v_2$, triangular, $v_3$, and quadrangular, $v_4$, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions and (anti-)protons in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range $|\eta|<0.8$ at different collision centralities and as a function of transverse momentum, $p_{\rm T}$, out to $p_{\rm T}=20$ GeV/$c$. The observed non-zero elliptic and triangular flow depends only weakly on transverse momentum for $p_{\rm T}>8$ GeV/$c$. The small $p_{\rm T}$ dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to $p_{\rm T}=8$ GeV/$c$. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least $p_{\rm T}=8$ GeV/$c$ indicating that the particle type dependence persists out to high $p_{\rm T}$.Comment: 16 pages, 5 captioned figures, authors from page 11, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186