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Resumen de la conferencia invitada presentada en: 8º Congreso Forestal Español. Lleida 21 junio a 1 de julio (2022), Este trabajo ha sido financiado por el Programa Interreg Sudoe dentro del proyecto Open2preserve (SOE2/P5/E0804) (https://open2preserve.eu). Asimismo, se recibió financiación del MICINN (fondos FEDER) dentro del proyecto LifeWatch ERIC - SUMHAL (SUMHAL, LIFEWATCH-2019- 09-CSIC-13, POPE 2014-2020) (https://lifewatcheric-sumhal.csic.es).

Background: Mediterranean and low-fat diets are effective in the primary prevention of cardiovascular disease. We did a long-term randomised trial to compare the effects of these two diets in secondary prevention of cardiovascular disease. Methods: The CORDIOPREV study was a single-centre, randomised clinical trial done at the Reina Sofia University Hospital in Córdoba, Spain. Patients with established coronary heart disease (aged 20–75 years) were randomly assigned in a 1:1 ratio by the Andalusian School of Public Health to receive a Mediterranean diet or a low-fat diet intervention, with a follow-up of 7 years. Clinical investigators (physicians, investigators, and clinical endpoint committee members) were masked to treatment assignment; participants were not. A team of dietitians did the dietary interventions. The primary outcome (assessed by intention to treat) was a composite of major cardiovascular events, including myocardial infarction, revascularisation, ischaemic stroke, peripheral artery disease, and cardiovascular death. This study is registered with ClinicalTrials.gov, NCT00924937. Findings: From Oct 1, 2009, to Feb 28, 2012, a total of 1002 patients were enrolled, 500 (49·9%) in the low-fat diet group and 502 (50·1%) in the Mediterranean diet group. The mean age was 59·5 years (SD 8·7) and 827 (82·5%) of 1002 patients were men. The primary endpoint occurred in 198 participants: 87 in the Mediterranean diet group and 111 in the low-fat group (crude rate per 1000 person-years: 28·1 [95% CI 27·9–28·3] in the Mediterranean diet group vs 37·7 [37·5–37·9] in the low-fat group, log-rank p=0·039). Multivariable-adjusted hazard ratios (HRs) of the different models ranged from 0·719 (95% CI 0·541–0·957) to 0·753 (0·568–0·998) in favour of the Mediterranean diet. These effects were more evident in men, with primary endpoints occurring in 67 (16·2%) of 414 men in the Mediterranean diet group versus 94 (22·8%) of 413 men in the low-fat diet group (multiadjusted HR 0·669 [95% CI 0·489–0·915], log-rank p=0·013), than in 175 women for whom no difference was found between groups. Interpretation: In secondary prevention, the Mediterranean diet was superior to the low-fat diet in preventing major cardiovascular events. Our results are relevant to clinical practice, supporting the use of the Mediterranean diet in secondary prevention. Funding: Fundacion Patrimonio Comunal Olivarero; Fundacion Centro para la Excelencia en Investigacion sobre Aceite de Oliva y Salud; local, regional, and national Spanish Governments; European Union. © 2022 Elsevier Ltd

PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks.

En condiciones de cambio climático, el uso óptimo del recurso hídrico y adecuado manejo agronómico, tienen como propósito incrementar el rendimiento y calidad de las cosechas, en tal sentido, el objetivo del ensayo fue evaluar el efecto de tres caudales hídricos suministrados por goteo (C1-1,6 LH-1; C2-1,4LH-1 y C3-1,2 LH-1); en el rendimiento y contenido de antocianinas en cultivares de maíz morado (V1:PMV-581; V2:MMMejorado y V3:MMComun) . Se utilizó el DBCA con factorial. Los resultados para diámetro de mazorcas reportaron que las interacciones C1xV2 y C1xV1, registraron promedios de 4,83 y 4,77 cm respectivamente; para peso de mazorcas por área neta con la interacción C1xV1 se obtuvo el mayor promedio de 4,78 kg, y asimismo un rendimiento equivalente a 11 950 kg.ha-1 .Mayor contenido de antocianinas se obtuvo con la interacción C1xV1 con 88,71 mg.L-1; y con la C2xV1 se obtuvo 74,95 mg.L-1. Se concluye que la interacción C1V1 denoto el mayor rendimiento por hectárea así como el mayor contenido de antocianinas.

The stereospecific removal of iodine from thyroid hormones is an essential first step for T3 action and is catalyzed by three different deiodinases: D2 and D3 remove iodine only from the outer or inner ring, respectively, whereas D1 catalyzes both pathways. We used in silico predictions from vertebrate deiodinase sequences to identify two domains: the N-terminal variable region (VR) containing the transmembrane, hinge and linker domains, and the conserved or globular region (CR). Given the high sequence and structural identity of the CR among paralogs as well as of the VR among orthologs but not paralogs, we hypothesized that both the catalytic properties and the subcellular localization rely on the VR. We used shark D2 and D3 as templates to build the chimeric enzymes D2VR/D3CR and D3VR/D2CR. Biochemical characterization revealed that D3VR/D2CR has inner-ring deiodination activity and T3 as preferred substrate, whereas D2VR/D3CR showed no deiodinating activity. Also, D2VR/D3CR and D3VR/D2CR reside in the endoplasmic reticulum and plasmatic membrane, respectively, as do their D2 and D3 wild-type counterparts. We conclude that the VR determines the subcellular localization and is critical in defining the catalytic properties and activity of thyroid hormone deiodinases.

From an evolutionary perspective, deiodinases may be considered pivotal players in the emergence and functional diversification of both thyroidal systems (TS) and their iodinated messengers. To better understand the evolutionary pathway and the concomitant functional diversification of vertebrate deiodinases, in the present review we summarized the highlights of the available information regarding this ubiquitous enzymatic component that represents the final, common physiological link of TS. The information reviewed here suggests that deiodination of tyrosine metabolites is an ancient feature of all chordates studied to date and consequently, that it precedes the integration of the TS that characterize vertebrates. Phylogenetic analysis presented here points to D1 as the oldest vertebrate deiodinase and to D2 as the most recent deiodinase gene, a hypothesis that agrees with the notion that D2 is the most specialized and finely regulated member of the family and plays a key role in vertebrate neurogenesis. Thus, deiodinases seem to be major participants in the evolution and functional expansion of the complex regulatory network of TS found in vertebrates.

Thyroid hormone bioactivity is finely regulated at the cellular level by the peripheral iodothyronine deiodinases (D). The study of thyroid function in fish has been restricted mainly to teleosts, whereas the study and characterization of Ds have been overlooked in chondrichthyes. Here we report the cloning and operational characterization of both the native and the recombinant hepatic type 3 iodothyronine deiodinase in the tropical shark Chiloscyllium punctatum. Native and recombinant sD3 show identical catalytic activities: a strong preference for T3-inner-ring deiodination, a requirement for a high concentration of DTT, a sequential reaction mechanism, and resistance to PTU inhibition. The cloned cDNA contains 1298 nucleotides [excluding the poly(A) tail] and encodes a predicted protein of 259 amino acids. The triplet TGA coding for selenocysteine (Sec) is at position 123. The consensus selenocysteine insertion sequence (SECIS) was identified 228 bp upstream of the poly(A) tail and corresponds to form 2. The deduced amino acid sequence was 77% and 72% identical to other D3 cDNAs in fishes and other vertebrates, respectively. As in the case of other piscivore teleost species, shark expresses hepatic D3 through adulthood. This characteristic may be associated with the alimentary strategy in which the protection from an exogenous overload of thyroid hormones could be of physiological importance for thyroidal homeostasis.

SUMMARY The physiological role played by thyroid hormones (TH) in hydro-osmotic homeostasis in fish remains a controversial issue. Previous studies have shown that in Fundulus heteroclitus (killifish) hypo-osmotic stress increases liver iodothyronine deiodinase type 2 (D2) mRNA and D2 activity. In this study we identified two conserved osmotic response element (ORE) motifs in the promoter region of the killifish D2 gene (FhDio2) and examined their possible role in the transcriptional regulation of FhDio2during hypo-osmotic stress. As assessed by the electrophoretic mobility shift assay, results from in vivo and in vitro experiments demonstrate that exposure to an abrupt hyposmotic challenge triggers in the liver of killifish a strong nuclear recruitment of a putative osmotic response element binding protein (OREBP). This protein–DNA binding is time-dependent, attains a maximum within 2–8 h after the osmotic stress,and is followed by a significant increase in D2 activity. Furthermore,protein–DNA binding and the subsequent elevation in enzyme activity were blocked by the tyrosine kinase inhibitor genistein. Thus, during hypo-osmotic stress, a putative OREBP kinase-activated pathway stimulates FhDio2transcription and enzymatic activity. These data and the fact that D2 is the major enzyme providing local intracellular T3 suggest that TH plays a direct role in osmoregulation in fish, possibly by participating in hepatic ammonia metabolism. This study provides important insight into the physiological role of TH in hydro-osmotic homeostasis in fish.

An accurate assessment of the animal’s requirements is of utmost importance for a balanced nutrition of farm animals. In this review we describe the results from a series of experiments, performed during the last years by our research group, aiming at assessing the utilization of dietary protein by the Iberian pig throughout the different stages of its productive cycle. Nutritional doseresponse studies involving several isoenergetic treatments differing in proteinconcentration -all with similar aminoacid profile following the ideal proteinconcept- along with comparative growth and metabolic studies with conventional breeds have been performed. Our observations reveal that the capacity of this breed for protein accretion is rather limited compared to that of conventional or lean breeds at similar stages of growth. They also suggest the need for reducing the concentration of protein in the diet of the Iberian pig to comply with the metabolic profile of this native pig breed. We summarise all the information gathered during the last fifteen year sand provide recommendations on the level and composition of dietary protein in the diet for pure breed animals during the different phases of growth. An adequate nutritional management, particularly dietary protein provision, improves the efficiency of utilization of dietary protein and results in relevant economic, environmental and animal welfare benefits.

Introduction: RECIPE study was designed to assess the impact of dietary supplementation with fermented milk enriched with plant sterols (FMPS) on the nutritional behavior, lifestyle and the joint therapeutic responsibility of hypercholesterolemic patients. Methods: Observational, prospective, multicenter, international study, was conducted to assess dietary habits and other lifestyle components in hypercholesterolemic patients in whom the general practitioner indicated FMPS supplementation. Nutritional, lifestyle and clinical data were collected at the initial visit and after a 4 months follow-up. The biochemical and anthropometric data were retrieved from medical records obtained at baseline and 4 months. Results: We report the results of Spain. Two hundred and one physicians who provided valid data of 1044 patients participated. The addition of FMPS was associated with improved overall nutritional index, being adequate initially in 28.2% of patients, and increasing up to 75.2% at the end of the study (P< 001). This nutritional change was associated with an improvement in the lipid profile and anthropometric data. Patients more adherent to therapy generally achieved a better result in all parameters compared to non-compliant ones. Conclusions: The addition of FMPS to a diet designed to reduce the LDL enhances the patient's attitude regarding changes in lifestyle, leading to better overall control of dyslipidemia and anthropometric improvement. © 2012 Elsevier España, S.L. and SEA.

Substrate availability has been thought to be a major regulator of the outer-ring deiodinating pathway (ORD) in fish. However, current information strongly suggests that while fish iodothyronine deiodinase type 2 (D2) responds to iodothyronines in the same manner as its mammalian counterpart, fish deiodinase type 1 (D1) exhibits a distinct response. Furthermore, 3,5-T 2 , generally considered to be an inactive product of iodothyronine metabolism, has recently been described as bioactive, but its effects upon D1 and D2 are not yet known. We examined the effect that short-term immersion in T 4 , T 3 , and 3,5-T 2 (0.1 μM; 12 or 24 h) exerts on both D1 and D2 activities and on the levels of expression of D1 and D2 mRNAs in killifish liver. In agreement with previous reports in teleosts, no iodothyronine exerted a significant effect on D1 enzymatic activity. However, all three iodothyronines significantly decreased D2 activity. Furthermore, at 24 h post-immersion T 4 , T 3 , and 3,5-T 2 inhibited both D1 and D2 transcription. Together, the present results confirm the differential effect of iodothyronines upon the hepatic ORD pathway in fish and show that this effect can occur at a transcriptional level. Furthermore, we provide the first evidence that 3,5-T 2 can affect both activity and transcription of hepatic deiodinases in teleosts.

We measured the activities of iodothyronine-activating (D1 and D2) and -inactivating (D3) deiodinases, as well as the circulating levels of their corresponding substrates and/or products, T4 ,T 3 ,a nd rT 3, in the developing rainbow trout. The study was conducted through 20 consecutive months and included fry, fingerlings, and mature animals from 14 to 88 weeks post-hatching (ph). Initially, blood concentration of active iodothyronines was low and tissue D3 activity was greater than the activity of D1 and D2. As fry developed into fingerlings, the activity of liver D2 increased, while that of skin D3 declined. The time course of these changes was directly (T3) or inversely (rT3 and D3) correlated to an increase in age, length, and body weight. The initial increment in both circulating T3 and hepatic D2 activity during the first spring (March-April; weeks 46–50 ph) coincided with the onset of gonadal differentiation, whereas the highest values of T3 and hepatic D1 and D2 (September–October; weeks 70–74 ph) occurred at the onset of sexual maturity. These results suggest that a hepatic supply of active T3 is temporally associated with gametogenesis. Abbreviations: ANS – 8-anilin-1-naphthalene sulphonic acid; DTT – Dithiothreitol; ph – post-hatching; T4 – thyroxine; T3 – triiodothyronine; rT3 – reverse triiodothyronine; T2 – diiodothyronine.

Objetivos: Estimar la prevalencia de sífilis y VIH e identificar los comportamientos de riesgo asociados en personas privadas de libertad (PPL). Materiales y métodos: Estudio transversal realizado durante el año 1999 en 22 establecimientos penitenciarios peruanos. Se realizó RPR para la detección de sífilis (datos ligados) y ELISA para tamizaje de VIH (datos no ligados), confirmándose con IFI o Western Blot. Se realizó una encuesta estructurada y se analizaron los datos mediante los programas SPSS 9,0 y AMOS 4. Resultados: Participaron 6963 PPL. La prevalencia de VIH fue 1,1% y de sífilis 4,1%. Los comportamientos de riesgo asociados a VIH más significativos fueron: consumo de drogas (OR:2,7), infecciones de transmisión sexual (OR: 2,3), relaciones sexuales entre hombres (OR: 2,2), uso de cocaína (OR: 2,1), úlcera genital (OR: 2,1), haber sido encarcelado previamente (OR: 2) y tener tatuajes (OR: 1,99). Mientras los asociados a sífilis fueron: tener relaciones sexuales entre hombres OR: (2,8), infecciones de transmisión sexual (OR: 2,4), úlcera genital (OR:1,8), haber tenido relaciones sexuales con trabajadora sexual (OR: 1,5) y tener más de dos parejas sexuales (OR: 1,5). Utilizando un modelo de ecuaciones estructurales se asoció VIH con el reporte de tener tatuaje, más de dos parejas sexuales, más de un encarcelamiento previo y úlcera genital. Conclusiones: Se encontraron importantes valores de prevalencia de VIH y sífilis en este grupo de personas, siendo necesario continuar realizando estudios similares que nos permitan conocer las tendencias (vigilancia de segunda generación) y conocer el impacto de posibles intervenciones. Objective: To determine HIV and syphilis prevalence and to identify behavioral risk factors in jail prisoners. Materials and methods: Cross-sectional study conducted during 1999 in 22 Peruvian jails. RPR was used to detect syphilis (linked results) and ELISA to screen HIV (non-linked results). Positive results were confirmed with IFI and Western Blot. A structured survey was carried out, resulting data was analized with SPSS 9,0 and AMOS 4. Results: 6 963 PPL participated. HIV and syphilis seroprevalence were 1,1 % and 4,1% respectively.The most significant HIV risks factors were: drug abuse (OR: 2,7), sexually transmitted diseases (OR: 2,3), sexual intercourse between males (OR: 2,2), cocaine use (OR: 2,1), genital ulcer (OR: 2,1), previus incarcelation (OR:2), and having a tattoo (OR: 1,99). The most significant syphilis risks factors were, sexual intercourse between males (OR: 2,8), sexually transmitted diseases (OR: 2,4), genital ulcer (OR: 1,8), sexual intercourse with sex workers (OR: 1,5) and having more than two sexual partners (OR: 1,5). An association between HIV infection and having a tattoo, having more than two sexual partners, more than one previous imprisonment and genital ulcer, was found using a structural equation model. Conclusions: Important rates of HIV and Syphilis prevalence were found among this group, thus making necessary the performace of similar research that may allow the knowledge of new trends (second generation surveillance) and to assess the impact of possible interventions.

The presence of a type 1 deiodinase (D1) in the liver of teleosts has been a controversial issue. Recently we characterized the deiodinase activity in rainbow trout and killifish liver and found that the liver of both species co-expresses the two enzymes (D1 and D2) that catalyze the outer ring-deiodinating pathway. We here report the cloning and characterization of an mRNA from the liver of the killifish Fundulus heteroclitus that encodes a D1 (FhD1). The cDNA amplified by RT-PCR from F. heteroclitus liver is 1314 nt long and encodes a protein of 248 aa. It contains a TGA codon in its open reading frame and a selenocysteine insertion sequence in its 3′ untranslated region, consistent with the structure of a selenoenzyme mRNA. The deduced peptide sequence is 73% identical to that encoded by the tilapia D1 cDNA cloned from kidney and 46% identical to the D1s reported in other vertebrates. Northern blot analysis shows that FhD1 mRNA is expressed in F. heteroclitus liver, consistent with prior biochemical evidence for hepatic D1 activity. Furthermore, heterologous expression of the FhD1 cDNA resulted in a protein with properties similar to the D1-like activity in F. heteroclitus liver. The cloned enzyme, like the native species, is relatively insensitive to inhibition by PTU, but mutation of Ser-159 in FhD1 to the Pro residue found in D2 and D3 isoforms increased the sensitivity to PTU. Our results show that, under basal conditions, killifish liver indeed expresses a D1 enzyme that is homologous to mammalian D1s, establishing this as a useful model in which to study the regulation of D1 and D2 concurrently.

Recently, we reported the cloning of a cDNA fragment from Fundulus heteroclitus liver encoding the open reading frame of type 2 deiodinase (FhD2). We here report the cloning of 14 kb of genomic sequence from F. heteroclitus that includes the previously reported coding region of the F. heteroclitus Dio2 gene (FhDio2), the 5′ and 3′ untranslated regions, and flanking regions and introns. This FhDio2 gene comprises two exons divided by a 4.8-kb intron. The position of the intron is similar to that of introns in other Dio2 genes. The analysis of approximately 1.3 kb of genomic sequence upstream of the mRNA start site revealed that, in contrast to mammalian Dio2 genes, there were no apparent TATA or CRE sequences. Nevertheless, a putative Sp1 site was found, similar to that in other F. heteroclitus TATA-less promoters. We have also cloned the complete FhD2 cDNA, which spans 4652 bp and contains a sequence adjacent to its poly(A) tail that is highly similar to the selenocysteine insertion sequence (SECIS) found in human D2 cDNA. The expression of a construct containing the FhD2 ORF plus the native SECIS resulted in a protein with deiodinase activity similar to that of the native FhD2. Analysis of the regulation of this gene, combined with ongoing studies of the F. heteroclitus D1 gene, will allow us to elucidate the functions of the colocalized deiodinases in teleost liver.

In this study we analyzed whether corticosterone synthesis is involved in the regulation of adrenal gland type II deiodinase (AG-D2) activity during acute cold exposure. Two well-known inhibitors of steroidogenesis, aminoglutethimide (AGT) and metyrapone (MTP), were administered to male Wistar rats maintained either at room temperature or acutely exposed to cold (1 h at 4°C). AG-D2 activity was measured by the radioiodide release method, and corticosterone circulating levels were measured by competitive protein binding assay. Results show that resting corticosterone levels and AG-D2 activity were lower in both AGT-and MTP-treated rats. Furthermore, the phasic increase normally exhibited by AG-D2 activity in response to acute cold stress was blunted in AGT-and MTP-treated animals. Therefore, we conclude that corticosterone synthesis is necessary in preserving the physiologic response of Ag-D2 activity to cold exposure.

The kinetic characterization of the outer-ring deiodination pathway using rT(3) (rT(3)-ORD) in male, female, and pregnant female livers of an endemic lizard, Sceloporus grammicus, is reported. The ORD pathway does not have the characteristics of deiodinase type II; it is exclusively carried out by deiodinase type I (DI). DI enzymatic activity in lizard liver contains one of the highest activities reported in vertebrates. This activity is sexually dimorphic, with males presenting the highest activity during the reproductive season. The properties of this enzyme correspond to those described in mammals, such as specificity for rT(3), susceptibility to inhibition by 6-n-propyl-2-thiouracil and gold-thioglucose, cofactor requirement, and kinetic pattern. Unlike other vertebrates, the lizard DI exhibits conspicuous stability in the thermal range of 15 to 42 degrees C and in the pH range of 5.0 to 9.0. Male true kinetic constants exhibit a direct correlation with temperature. This is in agreement with short-term adaptation to microenvironmental changes and the feasible expression of enzymatic forms/variants which, together, endow this lizard species with a greater adaptation to natural daily ambient thermal fluctuations.

Mammary deiodinase type I (M-D1) is present only during lactation and exhibits a clear direct correlation with lactation intensity (size of litters). The present work shows that M-D1 is suckling dependent and that intervals between suckling periods no longer than 12 h are essential to maintain this activity. Moreover, we find that with only 15 min of resuckling in 12-h nonsuckled mothers, the 50% decrease in both M-D1 messenger RNA and enzymatic activity could be restored to control values. This restorative effect by suckling may involve pre- and posttranscriptional mechanisms in which norepinephrine and PRL play important roles. Norepinephrine elicits a potent stimulatory effect on M-D1 messenger RNA and enzyme activities, whereas PRL only increases M-D 1 activity and may modulate the enzyme response to norepinephrine. Oxytocin and GH had no effect. These data suggest that the adrenergic nervous system and PRL could directly participate in mammary energetic expenditure, regulating the local T3 supply.

Iodothyronine deiodinases, a ubiquitous family of selenoenzymes, are key tissue-specific regulators of intracellular thyroid hormone availability and signaling. This chapter reviews current information supporting the notion that the altered expression and/or activity of deiodinases contribute to the pathophysiology of diverse clinical disorders. Experimental and clinical evidence establishes an association of polymorphisms in deiodinase genes with mood, affective and cognitive functioning, as well as type 2 diabetes mellitus and lipid metabolism. Similarly, an imbalance in the activating and inactivating deiodinase pathways may promote cell proliferation and/or invasiveness of different types of neoplasms. Although a clear-cut picture has not yet been achieved, emerging data support the notion that the deiodinase-dependent thyroid hormone transcriptional footprint has a profound functional impact in health and disease.

Lactating rat mammary gland expresses a deiodinating activity that, on the basis of kinetic characteristics, corresponds to the socalled 59-deiodinase type I (D1). In the present study we amplified and sequenced several D1 complementary DNA (cDNA) fragments from rat lactating mammary gland. The mammary cDNA was found to be identical to the previously reported rat liver cDNA in the coding region, but 465 nucleotides shorter on its 39-untranslated region, suggesting that the D1 is the same in both tissues. D1 messenger RNA (mRNA) was also detected by reverse transcriptase-PCR in mammary glands from puberal and late pregnant rats, but not in virgin animals. Densitometric analysis showed a close and direct correlation between mRNA content and enzyme specific activity in mammary gland. Our results also show that rat liver contains both D1 mRNA forms and that the large form may respond to the thyroid status. These data suggest a differential and organ-specific expression of these mRNA forms, which could play a role in the functional regulation of D1 activity. (Endocrinology 138: 4248 ‐ 4254, 1997)

Recent molecular cloning studies in mammals and amphibians have demonstrated that the types I, II, and III deiodinases constitute a family of selenoproteins of critical importance in metabolizing T4 to active (i.e. T3) and inactive (i.e. rT3) metabolites. In several tissues of teleost fish, various deiodinase processes have been described, but the structural and functional characteristics of these enzymes and their relationship to the deiodinases present in higher vertebrates remains uncertain. Using a complementary DNA library derived from the liver of the teleost Fundulus heteroclitus, we have identified a complementary DNA that codes for a deiodinase with functional characteristics virtually identical to those of the mammalian and amphibian type II deiodinase. Sequence analysis demonstrates a high degree of homology at both the nucleotide and predicted amino acid levels between the Fundulus clone and these previously characterized type II enzymes, including the presence of an in-frame TGA codon that codes for selenocysteine. These findings demonstrate that the deiodinase family of selenoproteins has been highly conserved during vertebrate evolution and underscores their importance in the regulation of thyroid hormone action.

Deiodinases are major determinants of thyroid hormone tissue availability and disposal. The knowledge of the expression of these enzymes in lower species is important to understand evolutionary and ontogenetic aspects of thyroid hormone action and metabolism. Here we have studied outer ring deiodination in the trout liver using both reverse T3 (rT3) and T4 as substrates. The use of rT3 disclosed two enzymatic components with the characteristics of mammalian types I and II 5′-deiodinases. The high rT3-Km type I 5′-deiodinase activity (180 nm) has a low cofactor requirement (5 mm dithiothreitol) and is relatively sensitive to propylthiouracil inhibition, whereas the low rT3-Km activity was akin to the outer ring deiodination of T4 in these regards. The use of T4 exhibited only a single type of activity with a low Km (0.63 nm), a relatively high cofactor requirement (25 mm dithiothreitol), and propylthiouracil-resistance. Teleosts constitute a unique example of type II activity expression in the liver of an ...

Recent studies in our laboratory have shown that in some teleosts, 3,5-di-iodothyronine (T2 or 3,5-T2) is as bioactive as 3,5,3′-tri-iodothyronine (T3) and that its effects are in part mediated by a TRβ1 (THRB) isoform that contains a 9-amino acid insert in its ligand-binding domain (long TRβ1 (L-TRβ1)), whereas T3 binds preferentially to a short TRβ1 (S-TRβ1) isoform that lacks this insert. To further understand the functional relevance of T2 bioactivity and its mechanism of action, we used in vivo and ex vivo (organotypic liver cultures) approaches and analyzed whether T3 and T2 differentially regulate the S-TRβ1 and L-TRβ1s during a physiological demand such as growth. In vivo, T3 and T2 treatment induced body weight gain in tilapia. The expression of L-TRβ1 and S-TRβ1 was specifically regulated by T2 and T3 respectively both in vivo and ex vivo. The TR antagonist 1–850 effectively blocked thyroid hormone-dependent gene expression; however, T3 or T2 reversed 1–850 effects only on S-TRβ1 or L-TRβ1 expression, respectively. Together, our results support the notion that both T3 and T2 participate in the growth process; however, their effects are mediated by different, specific TRβ1 isoforms.

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The aim of this essay is to present our initial experience with laparoscopic pyeloplasty and highlight how some specific technical changes allowed us to improve our results. We performed a chart review of the patients that underwent laparoscopic pyeloplasty in our institution. We included patients older than 6 months old with proved stenosis of the ureteropelvic junction. We compared our first patients with the last ones in which we performed laterocolic approach in all left pyeloplasties and included a modification of the technique to place an external ureteric stent. We performed 13 laparoscopic pyeloplasties, 8 male patients and 5 female. There were 3 right pyeloplasties (23%) and 10 left ones (77%). We performed transmesocolic approach in 2 cases (left) and laterocolic approach in 11. Mean surgical time was 184 minutes in the first 8 cases and 142 in the 5 last ones. We had three cases of complications in the first group, two stents migrated to ureter and one postsurgical infection. In the last cases we had a postoperative bleeding. Laparoscopic approach is an effective option for pyeloplasty with similar results to those of the open approach in spite of a longer surgical time. Experience and specific surgical details allow us to reduce complication rate and surgical time.

26th European Photovoltaic Solar Energy Conference and Exhibition; 3835-3839, A refined life-cycle assessment of polymer solar cells is presented with a focus on critical components, i.e. the transparent conductive ITO layer and the encapsulation components. This present analysis gives a comprehensive sketch of the full environmental potential of polymer-OPV in comparison with other PV technologies. It is shown that on a m2 basis the environmental characteristics of polymer-OPV are highly beneficial, while on a watt-peak and on a kWh basis, these benefits are – at the current level of the development - still (over-)compensated by low module efficiency and limited lifetime expectancy. The findings of this study underscore that, from an environmental and sustainability point of view, the replacement of the ITO layer and the optimization of encapsulation concepts should be in the spotlight of any near-term R&D efforts of the OPV community. Solutions to both of these technological issues are actively pursued. Some of these are discussed as examples in this paper.

The ontogeny of 5'-monodeiodinase activity (5'-MA) was analyzed in chick embryo brain and liver tissue. The enzymatic type predominant in this path and the activity of the deactivating pathway (5 MA-III) were determined during certain periods of neural development in both organs. Results show that T3 is predominantly formed in both organs during the first third of embryogenesis (from day 5) until neuroblast proliferation (day 13). Within this lapse, the slow type II enzyme (insensible to propylthiouracil) is present in the brain, whereas in the liver the predominating enzyme is type I (the rapid enzyme). Further along the synaptogenesis period (day 14-17), 5' deiodination virtually disappears in the brain, the hepatic type I enzyme switches to the slow autoconsume enzyme (type II), and 5 MA-III levels increase significantly in both organs. Finally, on days 18-20 (perinatal period) the 5' pathway reaches the highest levels observed throughout the study in both tissues. Associated to this increase, liver enzymatic activity returns to type I. During this period, 5 MA-III is reduced by 40% in the brain and disappears from the liver. Together, these data strengthen the notion of a protective mechanism against brain overexposure to T3 during synaptogenesis and suggest that the protective mechanism also involves the regulation of extraneural deiodinases.

We determined the kinetic parameters as well as the fractional turnover rate (FTr) and half-life (t(1/2)) of rat adrenal gland 5'deiodinase activity (AG-5'D). Adrenal glands from male euthyroid or surgically thyroidectomized (Tx) Wistar rats were homogenized (HEPES, 10MM: ; pH 7.5; sucrose, 0.25M: ; EDTA 1MM: ) and centrifuged at 10,000g for 15 min at 4°C. The resulting crude microsomal supernatants were used for ail measurements of 5'D activity. Using rT(3) (2-500NM: ) the true Km and the Vmax values were of 20.2NM: and 289 fmol of I(-) release/mg protein/h. With T(4) as substrate these values were 5.8NM: and 622 fmol/h/mg protein. Protein inhibitor (cycloheximide 6 mg/100 g wt) administration allowed to determine an FTr of 0.68 h(-1) and a t(1/2) of 1.01 h. Results demonstrate that the greatest 5'D activity in the rat adrenal gland corresponds to isotype II, because the reaction is GTG and PTU-resistant (70-80%), accepts T(4) as a far better substrate than rT(3) (17-fold) and the former thyronine has a 50-90% inhibitory concentration in the 4-100NM: range. Furthermore, rats thyroidectomized for 5 and 15 days showed a conspicuous increase in cerebral cortex and adrenal 5'D-II activity. These characteristics as well as the rapid FTr and short †(1/2) are shared by type II 5'D present in rat pineal, pituitary and brain.

Iodide is a trace element and a key component of thyroid hormones (TH). The availability of this halogen is the rate-limiting step for TH synthesis; therefore, thyroidal iodide uptake and recycling during TH synthesis are of major importance in maintaining an adequate supply. In the rat, the thyroid gland co-expresses a distinctive pair of intrathyroidal deiodinating enzymes: the thyroid iodotyrosine dehalogenase (tDh) and the iodothyronine deiodinase type 1 (ID1). In the present work, we studied the activity of these two dehalogenases in conditions of hypo- and hyperthyroidism as well as during acute and chronic iodide administration in both intact and hypophysectomized (HPX) rats. In order to confirm our observations, we also measured the mRNA levels for both dehalogenases and for the sodium/iodide symporter, the protein responsible for thyroidal iodide uptake. Our results show that triiodothyronine differentially regulates tDh and ID1 enzymatic activities, and that both acute and chronic iodide administration significantly decreases rat tDh and ID1 activities and mRNA levels. Conversely, both enzymatic activities increase when intrathyroidal iodide is pharmacologically depleted in TSH-replaced HPX rats. These results show a regulatory effect by iodide on the intrathyroidal dehalogenating enzymes and suggest that they contribute to the iodide-induced autoregulatory processes involved in the Wolff-Chaikoff effect.

El objetivo fue analizar el pedigrí de cuatro ganaderías mexicanas (Los Encinos=ENC, Montecristo=MCR, Fernando de la Mora=FMO y San José=SJO) a través de estimaciones de parámetros poblacionales tales como el tamaño de población base, tamaño efectivo, número de ancestros, aportaciones porcentuales e intervalos generacionales. Además se analizó el efecto de la consanguinidad sobre el comportamiento de los animales (tienta y lidia al caballo y al torero) con un modelo animal que consideró como efectos fijos a grupo contemporáneo (año-época de nacimiento-sexo, el efecto de sexo sólo en tienta) y las covariables lineales de edad y consanguinidad del individuo; los efectos aleatorios fueron el valor genético del individuo y el error. Los pedigríes incluyeron de 3246 a 8279 animales nacidos entre 1904 y 2006; la información de comportamiento data de 1978 a 2006, variando de 202 a 2776 observaciones. Las consanguinidades promedio variaron entre 2,4% y 12,9%, con máximos individuales de 47,7% en MCR y de alrededor de 40% en las otras ganaderías. El número de ancestros como proporción de la población de referencia en MCR fue 12,3%, mientras que en FMO, ENC y SJO representaron 17,7%, 27,8% y 34,0%, respectivamente. Tres animales explicaron 50% del pedigrí en MCR y 13 o menos en las otras ganaderías. Los tres ancestros de MCR explicaron 22,6% y 20,2% del pedigrí de SJO y ENC, respectivamente. Las ganaderías MCR, SJO y ENC tienen un origen común. Las tendencias anuales de consanguinidad fueron negativas en ENC y SJO (-0,13±0,02 y -0,25±0,02, respectivamente; p

The three distinct but related isotypes of the iodothyronine deiodinase family: D1, D2, and D3, have been amply studied in vertebrate homeotherms and to a lesser extent in ectotherms, particularly in reptiles. Here, we report the molecular and kinetic characteristics of both the native and the recombinant hepatic D3 from the pine snake Pituophis deppei (PdD3). The complete PdD3 cDNA (1680 bp) encodes a protein of 287 amino acids (aa), which is the longest type 3 deiodinase so far cloned. PdD3 shares 78% identity with chicken and 71% with its other orthologs. Interestingly, the hinge domain in D3s, including PdD3, is rich in proline. This structural feature is shared with D1s, the other inner-ring deiodinases, and deserves further study. The kinetic characteristics of both native and recombinant PdD3 were similar to those reported for D3 in other vertebrates. True K(m) values for T(3) IRD were 9 and 11 nM for native and recombinant PdD3, respectively. Both exhibited a requirement for a high concentration of cofactor (40 mM DTT), insensitivity to inhibition by PTU (2 mM), and bisubstrate, sequential-type reaction kinetics. In summary, the present data demonstrate that the liver of the adult pine snake P. deppei expresses D3. Furthermore, this is the first report of the cloning and expression of a reptilian D3 cDNA. The finding of hepatic D3 expression in the adult pine snake P. deppei is consistent with results in adult piscine species in which the dietary T(3) content seems to regulate liver deiodinase expression. Thus, our present results support the proposal that hepatic D3 in adult vertebrates plays a sentinel role in avoiding an inappropriate overload of exogenous T(3) secondary to feeding in those species that devour the whole prey.

Five genetic evaluation models of registered Brahman cattle in Mexico were compared for birth weight (PN), weaning (PD), yearling (PA) and final weight at 550 days (PF), and their effect on genetic parameter estimation and EPD ordering were also assessed. Models differed on number of random factors; D, model with direct genetic effect (σ2d), DM, model like D plus maternal genetic effect (σ2m) and genetic covariance between genetic effects equal to zero (σdm = 0), DP, D like model plus maternal permanent effect (σ2p), DMC, DM like model plus covariance between genetic effects (σdm ≠ 0), and DMCP as the complete model, equal to DMC plus (σ2p). Models included the fixed effect of contemporary grouping (herd, sex, year and season of birth), and age of dam as linear and quadratic covariable. A likelihood ratio test (PRV) was performed for model comparison, and EPD reordering was quantified by Spearman rank correlation analysis. The PRV showed DMC as the best model for all variables, except in PD. For PD the best model was DP. A negative genetic correlation rdm (rdm = σdm2) was observed for PN, PA and PF (-0,86, -0,84 and -0,52, respectively) reducing the magnitude of total heritability estimates. For PD, DMC and DMCP did not converge. Correlation between selected models and the other compared models, suggested that there might be important and substantial changes on 10% of superior animals. Structure of data may modify the genetic parameter estimation if adjusting complex models; hence the model selection could be crucial before performing any genetic evaluation. Considerations were made concerning selective recording. &nbsp, Se realizó una comparación de modelos para la evaluación genética de variables de crecimiento, en los pesos al nacimiento (PN), destete (PD), año (PA) y 550 días (PF) de ganado Brahman de registro de México; con el propósito de cuantificar su efecto en la estimación de parámetros genéticos y la jerarquización de las diferencias esperadas de progenie estimadas (DEPs). Los modelos comparados diferían en componentes aleatorios y fueron, D con el efecto directo (σ2d); DM, igual a D pero incluyendo el efecto materno (σ2m) y con la covarianza entre los efectos de σ2dy σ2m(σdm) = 0; DP, como D más el efecto materno de ambiente permanente (σ2p); DMC, como DM pero con σdm≠ 0; y el modelo completo, DMCP, igual a DMC más σ2p. Además, incluyeron el efecto fijo de grupo contemporáneo (hato-sexo-año-época) y la covariable de edad de la madre (lineal y cuadrática). La comparación entre modelos se realizó mediante la prueba de proporción de verosimilitudes (PRV). Las DEPs de los modelos, se compararon por correlación (rango de Spearman). Según la PRV, en todas las variables, excepto PD, el mejor modelo de ajuste fue DMC. Para PD, el mejor modelo fue DP. En PN, PA y PF, se observó una rdm(rdm= σdm) negativa (–0,86, –0,84 y –0,52, respectivamente); lo que disminuyó la magnitud de los estimadores de índice de herencia total. Para PD, los modelos DMC y DMCP no alcanzaron la convergencia. La estimación de las correlaciones de rango entre los valores genéticos directos y maternos de los modelos seleccionados con respecto a los otros modelos comparados, indicó que puede existir cambio sustantivo en la jerarquización del 10% de la población con valores superiores. Se concluye que la estructura de los datos analizados puede afectar la estimación de parámetros genéticos en modelos complejos, por lo que es importante escoger el modelo apropiado antes de llevar al cabo una evaluación genética. Existen algunas consideraciones con respecto al registro selectivo que deben tomarse con reserva sobre todo en evaluaciones nacionales. &nbsp

Circulating levels of T4, T3, corticosterone, noradrenaline, and adrenaline, as well as 5'-monodeiodinase activity (5'-MA) were measured in control and hypophysectomized rats acutely exposed to cold environment (15-120 min, 4 C). In addition to the well known activation of the sympathoadrenomedullary system and the hypothalamic-pituitary-adrenal and-thyroid axes, cold exposure was followed by a rapid and sustained increase of 5'-MA in the hypothalamus, and a byphasic course of activation in the adrenal gland in control rats. The adrenal rapid activation (30 min) corresponded to the medulla and the slower activation (120 min) to the cortex. Both, the basal adrenal 5'-MA and the response to cold in adrenal and hypothalamus were 2-fold higher in hypophysectomized rats compared to control. The time course of enzyme activation in these structures suggests that: 1) organ-specific increases in 5'-MA may be associated to a simultaneous rise in their metabolic and/or functional activity, 2) the triggering mechanisms involves an immediate sympathetic signal activating the hypothalamic-adrenal medulla response and a pituitary signal eliciting a slower adrenocortical response, and 3) the compensatory sympathetic hyperactivity after panhypopituitarism contribute to enhance both the adrenal enzyme basal activity and the hypothalamic and adrenal hyperresponse to cold stress.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 600-603, We have studied the modification by ultraviolet (UV) radiation and O3 exposure of the properties of thin films of poly-3-octyl-thiophene (P3OT). We prepared films of around 100 nm thickness by spin-coating on glass substrates. The samples were characterized by non-contact scanning force microscopy (NC-SFM) and by macroscopic electronic transport measurements for every cycle of UV radiation and O3 exposure. Our experimental technique allowed us to perform a nanoscale study of the same area or the sample and therefore we can attribute the observed changes to the effect of radiation. Also preliminary functional devices were prepared. The cells were kept in nitrogen atmosphere and characterized giving a power conversion efficiency around 0.03%, with a filling factor around 0.35. Those values are far from the best reported for organic solar cells, but it is worth to mention that our active layer is composed exclusively by P3OT. Subsequent characterization after exposing the thin films and cells to air and UV radiation shows a significant loss of efficiency and degradation of cell parameters like filling factor and short circuit current.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 3562-3565, The energetic and environmental Life Cycle Assessment (LCA) of a 4.2kWp Stand-Alone Photovoltaic System (SAPV) at the University of Murcia (south-east of Spain) is presented. Meteorological inputs and electrical outputs were recorded in order to use real generation data. A complete methodology for LCA applied to SAPV is presented. The methodology involves the material inventory, the life cycle energy use and the life cycle CO2 emissions for the three phases of a service facility: construction, operational and decommissioning phases. Also we have worked out the Embodied Energy Pay Back Time (EPBT) and the equivalent CO2-emission factor for the facility using real generation data for the analysis carried out. PV modules and batteries are the energetically and environmentally most expensive elements. The energy pay-back time was found to be 9,09 years and the specific CO2 emissions was calculated as 131 g/kWh. Construction processes are the energetically most intensive, while transport and recycling ones present low percentages. The SAPV system has been compared to other supply options (e.g., diesel generator and Spanish grid) showing lower impacts in both cases. The results show the CO2-emission reduction potential of SAPV systems in southern European countries and point out the critical environmental issues in these systems.

Se evaluó el efecto de factores ambientales en la producción de leche ajustada a 305 días (PLT), la producción (PP) y los días al pico (DPP) de lactancia, y la persistencia (PER) en vacas Holstein de agroempresas familiares con diferente nivel tecnológico (NT) en el estado de Jalisco, México. La información analizada (n= 4323 mediciones de producción diaria de leche de 537 lactancias) provino de 16 hatos. Las agroempresas se tipificaron como de bajo, medio o alto NT. El modelo mixto incluyó los efectos fijos de NT, número, año y estación de parto. La PLT en el NT bajo fue similar (P>0,05) entre épocas; sin embargo, en el NT medio la PLT en lluvias fue 11% mayor que en secas; mientras que en el NT alto la situación se invirtió, observándose una interacción similar para PP. Las vacas en bajo o alto NT presentaron más tarde (P0,05) entre épocas; no entanto, no NT médio a PLT nos períodos de chuva foi 11% maior que nos de seca; enquanto que no NT alto a situação se inverteu, observando-se uma interação similar para PP. As vacas em baixo ou alto NT apresentaram mais tarde (P

Until recently, 3,5-diiodothyronine (3,5-T2) has been considered an inactive by-product of triiodothyronine (T3) deiodination. However, studies from several laboratories have shown that 3,5-T2has specific, nongenomic effects on mitochondrial oxidative capacity and respiration rate that are distinct from those due to T3. Nevertheless, little is known about the putative genomic effects of 3,5-T2. We have previously shown that hyperthyroidism induced by supraphysiological doses of 3,5-T2inhibits hepatic iodothyronine deiodinase type 2 (D2) activity and lowers mRNA levels in the killifish in the same manner as T3and T4, suggesting a pretranslational effect of 3,5-T2(Garcia-G C, Jeziorski MC, Valverde-R C, Orozco A. Gen Comp Endocrinol 135: 201–209, 2004). The question remains as to whether 3,5-T2would have effects under conditions similar to those that are physiological for T3. To this end, intact killifish were rendered hypothyroid by administering methimazole. Groups of hypothyroid animals simultaneously received 30 nM of either T3, reverse T3, or 3,5-T2. Under these conditions, we expected that, if it were bioactive, 3,5-T2would mimic T3and thus reverse the compensatory upregulation of D2 and tyroid receptor β1 and downregulation of growth hormone that characterize hypothyroidism. Our results demonstrate that 3,5-T2is indeed bioactive, reversing both hepatic D2 and growth hormone responses during a hypothyroidal state. Furthermore, we observed that 3,5-T2and T3recruit two distinct populations of transcription factors to typical palindromic and DR4 thyroid hormone response elements. Taken together, these results add further evidence to support the notion that 3,5-T2is a bioactive iodothyronine.

We review the experimental evidence accumulated within the past decade regarding the physiologic, biochemical, and molecular characterization of iodothyronine deiodinases (IDs) in piscine species. Agnathans, chondrichthyes, and teleosts express the three isotypes of IDs: ID1, ID2, and ID3, which are responsible for the peripheral fine-tuning of thyroid hormone (TH) bioactivity. At the molecular and operational level, fish IDs share properties with their corresponding vertebrate counterparts. However, fish IDs also exhibit discrete features that seem to be distinctive for piscine species. Indeed, teleostean ID1 is conspicuously resistant to propylthiouracil (PTU) inhibition, and its response to thyroidal status differs from that exhibited by other ID1s. Moreover, both the high level of ID2 activity and its expression in the liver of teleosts are unique among vertebrates. The physiologic role of iodothyronine deiodination in functions regulated by TH in fish is not entirely clear. Nevertheless, current experimental evidence suggests that IDs may coordinate and facilitate, in a tissue-specific fashion, the action of iodothyronines and other hormones involved in such processes.

The initial characterization of a thyroid iodotyrosine dehalogenase (tDh), which deiodinates mono-iodotyrosine and di-iodotyrosine, was made almost 50 years ago, but little is known about its catalytic and kinetic properties. A distinct group of dehalogenases, the so-called iodothyronine deiodinases (IDs), that specifically remove iodine atoms from iodothyronines were subsequently discovered and have been extensively characterized. Iodothyronine deiodinase type 1 (ID1) is highly expressed in the rat thyroid gland, but the co-expression in this tissue of the two different dehalogenating enzymes has not yet been clearly defined. This work compares and contrasts the kinetic properties of tDh and ID1 in the rat thyroid gland. Differential affinities for substrates, cofactors and inhibitors distinguish the two activities, and a reaction mechanism for tDh is proposed. The results reported here support the view that the rat thyroid gland has a distinctive set of dehalogenases specialized in iodine metabolism.

We review the role of iodothyronine deiodinases (IDs) in the evolution of vertebrate thyroidal systems within the larger context of biological metabolism of halogens. Since the beginning of life, the ubiquity of organohalogens in the biosphere has provided a major selective pressure for the evolution and conservation of cellular mechanisms specialized in halogen metabolism. Among naturally available halogens, iodine emerged as a critical component of unique developmental and metabolic messengers. Metabolism of iodinated compounds occurs in the three major domains of life, and invertebrate deuterostomes possess several biochemical traits and molecular homologs of vertebrate thyroidal systems, including ancestral homologs of IDs identified in urochordates. The finely tuned cellular regulation of iodometabolite uptake and disposal is a remarkable event in evolution and might have been decisive for the explosive diversification of ontogenetic strategies in vertebrates.

La realización del presente proyecto de inversión tiene por finalidad estudiar la factibilidad de comercializar un servicio diseñado para aquellas personas que presenten sobrepeso corporal, que no dispongan de mucho tiempo para asistir a tratamientos presénciales, tales como gimnasios o tratamientos con termogénesis, y que además la inversión en la compra del servicio brindado no sea de gran impacto para su economía Tesis

Recently, we reported the cloning of a cDNA fragment from Fundulus heteroclitus liver encoding the open reading frame of type 2 deiodinase (FhD2). We here report the cloning of 14 kb of genomic sequence from F. heteroclitus that includes the previously reported coding region of the F. heteroclitus Dio2 gene (FhDio2), the 5(') and 3(') untranslated regions, and flanking regions and introns. This FhDio2 gene comprises two exons divided by a 4.8-kb intron. The position of the intron is similar to that of introns in other Dio2 genes. The analysis of approximately 1.3 kb of genomic sequence upstream of the mRNA start site revealed that, in contrast to mammalian Dio2 genes, there were no apparent TATA or CRE sequences. Nevertheless, a putative Sp1 site was found, similar to that in other F. heteroclitus TATA-less promoters. We have also cloned the complete FhD2 cDNA, which spans 4652 bp and contains a sequence adjacent to its poly(A) tail that is highly similar to the selenocysteine insertion sequence (SECIS) found in human D2 cDNA. The expression of a construct containing the FhD2 ORF plus the native SECIS resulted in a protein with deiodinase activity similar to that of the native FhD2. Analysis of the regulation of this gene, combined with ongoing studies of the F. heteroclitus D1 gene, will allow us to elucidate the functions of the colocalized deiodinases in teleost liver.

In the hillsides, rice is stable in the diet of the poor. Therefore it is important to develop upland rice with cold tolerance to help confront food insecurity in the mid-altitude mountains. A participatory scheme allowing the farmers to select for the characteristics that the identify as important including acid soil, drought and cold tolerance, and for resistance to rice blast disease. A participatory process of evaluation led to the nomination of the varieties Cirad 446 and Cirad 447. They are the first upland varieties in America with earliness, high tolerance to cold, drought and soil acidity, and with resistance to blast. So they are the first varieties of a new type of Rice for Hlllsides with COld tolerance, named RHICO type.

Conversion of T4 to T3 is the first step in TH action and deiodinases are the major determinants of TH tissue availability and disposal. We here report the kinetic characterization of the outer-ring deiodinating (ORD) enzymes in the liver, gill and retina of sea water-adapted killifish, by using both rT3 and T4 as substrates. In liver, by using rT3, we detected a high Km (84 nM) and a low Km (1.3 nM) component with kinetic characteristics similar to mammalian deiodinases DI and DII. In contrast, T4-ORD only generated a low Km (0.5 nM) component. As judged by its Vmax (920 fmol 125I/mg per h) this DII enzyme is very abundant, approximately five and 20 times higher than that found in trout liver and hypothyroid rat, respectively. Kinetic analysis in killifish gill showed only one enzymatic component, with a high rT3 Km (430 nM) and a relatively low Vmax (4.3 pmol 125I/mg per h). Our results in killifish retina show the expression of a T4-low Km (0.6 nM) deiodinase with high cofactor requirements akin to the mammalian DII. The Vmax value for this enzyme is 182 fmol 125I/mg per h, five times lower than the one found in killifish liver, but comparable to that in hypothyroid rat pituitary. The biochemical similarities between fish and mammalian deiodinases could reflect their high conservation during vertebrate evolution and thus their importance in the regulation of thyroid hormone action.