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1.
Phys Rev Lett ; 130(4): 040201, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36763429

RESUMO

Bell nonlocality and Kochen-Specker contextuality are two remarkable nonclassical features of quantum theory, related to strong correlations between outcomes of measurements performed on quantum systems. Both phenomena can be witnessed by the violation of certain inequalities, the simplest and most important of which are the Clauser-Horne-Shimony-Holt (CHSH) and the Klyachko-Can-Binicioglu-Shumovski (KCBS), for Bell nonlocality and Kochen-Specker contextuality, respectively. It has been shown that, using the most common interpretation of Bell scenarios, quantum systems cannot violate both inequalities concomitantly, thus suggesting a monogamous relation between the two phenomena. In this Letter, we show that the joint consideration of the CHSH and KCBS inequalities naturally calls for the so-called generalized Bell scenarios, which, contrary to the previous results, allows for joint violation of them. In fact, this result is not a special feature of such inequalities: We provide very strong evidence that there is no monogamy between nonlocality and contextuality in any scenario where both phenomena can be observed. We also implement a photonic experiment to test the synchronous violation of both CHSH and KCBS inequalities. Our results agree with the theoretical predictions, thereby providing experimental proof of the coexistence of Bell nonlocality and contextuality in the simplest scenario, and lead to novel possibilities where both concepts could be jointly employed for quantum information processing protocols.

2.
Trop Anim Health Prod ; 51(6): 1661-1665, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30879247

RESUMO

The objective of this study was to evaluate the effect of biotin supplementation on milk yield and the reproductive efficiency in Girolando cows. The study was conducted on a dairy farm located in central Brazil, between April 2012 and December 2016. Thirty-six Girolando cows in their first lactation were used. The cows were distributed in two treatment groups, each with equivalent weight distributions. Control treatment (CT) cows (n = 18) received a diet without any supplemental biotin, whereas biotin treatment (BT) cows (n = 18) received a diet supplemented with 20 mg/day of biotin during lactation. Biotin supplementation caused a significant increase (p = 0.001) in milk yield in the second lactation, and a trend (p = 0.09) toward higher average production during the three lactations was evaluated. There was no statistically significant difference between the treatments in terms of reproductive efficiency. In conclusion, biotin supplementation (20 mg/day) during lactation for Girolando cows reared in a tropical climate is able to increase milk yield, but does not improve reproductive efficiency.


Assuntos
Biotina/farmacologia , Bovinos/fisiologia , Lactação/efeitos dos fármacos , Leite , Clima Tropical , Fenômenos Fisiológicos da Nutrição Animal , Animais , Biotina/administração & dosagem , Brasil , Dieta/veterinária , Suplementos Nutricionais , Feminino , Reprodução/efeitos dos fármacos
3.
Trop Anim Health Prod ; 50(7): 1631-1636, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29704090

RESUMO

We aimed to follow the epidemiologic evolution of bovine digital dermatitis (BDD) and other podal diseases grouped in a dairy farm in Central Brazil between the years 2010 and 2016. This study was carried out in a farm in Jataí, Goiás, Central Brazil, where the prevalence data of bovine digital dermatitis (BDD) and other podal diseases, as well as the composition, history, and management of the herd, was collected. We analyzed the collected data into the two annual pluviometric precipitation values in Central Brazil: rainy season and dry season. The cumulative frequency for comparison of prevalence between seasons throughout the years was calculated from 2011 to 2016. The comparison was carried out by post hoc chi-square test with the Bonferroni correction adopting a level of significance of 5% (p < 0.05). BDD was not diagnosed at the property in 2010; however, the disease became endemic from 2011, which coincides with the arrival of new animals to the herd. The comparison of the accumulated frequencies for prevalence of the diseases in the herd between 2011 and 2016 revealed BDD, as well as the grouped nutritional and metabolic foot diseases, has the highest prevalence in the period of lower annual precipitation in Central Brazil, which occurs between May and October. For a better control of BDD, we recommend greater attention in cattle management in the dry season of the year in Brazil, as well as in any other place in the world in which rainfall is seasonal.


Assuntos
Doenças dos Bovinos/epidemiologia , Dermatite Digital/epidemiologia , Doenças do Pé/veterinária , Chuva , Estações do Ano , Animais , Brasil/epidemiologia , Bovinos , Fazendas , Feminino , Doenças do Pé/epidemiologia , Masculino , Modelos Estatísticos , Prevalência
4.
Phys Rev Lett ; 117(19): 190401, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27858448

RESUMO

Entanglement allows for the nonlocality of quantum theory, which is the resource behind device-independent quantum information protocols. However, not all entangled quantum states display nonlocality. A central question is to determine the precise relation between entanglement and nonlocality. Here we present the first general test to decide whether a quantum state is local, and show that the test can be implemented by semidefinite programing. This method can be applied to any given state and for the construction of new examples of states with local hidden variable models for both projective and general measurements. As applications, we provide a lower-bound estimate of the fraction of two-qubit local entangled states and present new explicit examples of such states, including those that arise from physical noise models, Bell-diagonal states, and noisy Greenberger-Horne-Zeilinger and W states.

5.
Clin Exp Obstet Gynecol ; 40(1): 89-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23724516

RESUMO

PURPOSE OF INVESTIGATION: The fragile histidine triad (FHIT) gene is a tumor suppressor frequently inactivated in various types of tumors. The authors evaluated the occurrence of loss of heterozygosity (LOH) in the FHIT locus and FHIT protein changes in breast tissue. MATERIALS AND METHODS: Blood and breast tissue samples were obtained from 35 women with mammary disorders. The occurrence of LOH in FHIT locus was assayed by polymerase chain reaction (PCR), and the results obtained from blood and breast tissues from each patient were compared. FHIT protein expression was evaluated by immunohistochemistry. RESULTS: LOH in the FHIT gene occurred in 48.6% (17/35) of patients with mammary disorder. Among patients with malignant breast disorders, 59.1% (13/22) presented LOH in the FHIT gene in comparison with patients with benign breast lumps, in which the LOH was observed in 30.8% (4/13) of women, suggesting that changes in this gene occur prior to the process of mammary carcinogenesis. The changes in the locus of the FHIT gene occur with greater frequency in the coded region of the gene, principally near exons 5 and 8, where the FRA3B site and the histidine triad respectively are found. Changes in FHIT did not modify protein expression. The association between menopause and LOH in the FHIT gene was evident. CONCLUSIONS: LOH in the FHIT gene may be related to menopause in women with breast disorders.


Assuntos
Hidrolases Anidrido Ácido/genética , Neoplasias da Mama/genética , Proteínas de Neoplasias/genética , Hidrolases Anidrido Ácido/metabolismo , Neoplasias da Mama/metabolismo , Estudos Transversais , Feminino , Humanos , Perda de Heterozigosidade , Menopausa/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Fatores de Risco
6.
Braz J Med Biol Res ; 40(2): 153-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17273651

RESUMO

Elevated body mass index (BMI) has been reported as a risk factor for heart failure. Prevention of heart failure through identification and management of risk factors and preclinical phases of the disease is a priority. Levels of natriuretic peptides as well as activity of their receptors have been found altered in obese persons with some conflicting results. We investigated cardiac involvement in severely obese patients by determining N-terminal-pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) and attempting to correlate the levels of these peptides in serum and plasma, respectively, with BMI, duration of obesity, waist circumference, and echocardiographic parameters. Thirty-three patients with severe obesity (mean BMI: 46.39 kg/m(2), mean age: 39 years) were studied. The control group contained 30 healthy age-matched individuals (BMI: <25 kg/m(2), mean age: 43 years). The t-test and Spearman correlation were used for statistical analysis. Log-NT-proBNP was significantly higher (P = 0.003) in obese patients (mean 1.67, 95% CI: 1.50-1.83 log pg/mL) compared to controls (mean: 1.32, 95% CI: 1.17-1.47 log pg/mL). The Log-NT-proBNP concentration correlated with duration of obesity (r = 0.339, P < 0.004). No difference was detected in the Log-BNP concentration (P = 0.63) of obese patients (mean: 0.73, 95% CI: 0.46-1.00 log pg/mL) compared to controls (mean: 0.66, 95% CI: 0.51-0.81 log pg/mL). NT-proBNP, but not BNP, is increased in severely obese patients and its concentration in serum is correlated with duration of obesity. NT-proBNP may be useful as an early diagnostic tool for the detection of cardiac burden due to severe obesity.


Assuntos
Peptídeo Natriurético Encefálico/sangue , Obesidade Mórbida/sangue , Fragmentos de Peptídeos/sangue , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Ecocardiografia , Feminino , Cardiopatias/sangue , Cardiopatias/etiologia , Humanos , Medições Luminescentes , Masculino , Obesidade Mórbida/complicações , Fatores de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Fatores de Tempo , Relação Cintura-Quadril
7.
Anat Histol Embryol ; 46(5): 439-445, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28762238

RESUMO

The aim of this study was to describe the microstructure of hoof capsules of the buffalo. In addition, the study emphasized the morphometric aspects of the horn tubules, the Vickers nanohardness of the dorsal and abaxial walls and sole of the digits of the thoracic and pelvic limbs of the buffalo. The abaxial wall in the thoracic and pelvic digits showed larger diameter of the horn tubules when compared to all dorsal wall and sole. In addition, the abaxial wall of the thoracic digits showed larger diameter of the horn tubules when compared with the pelvic digits. According to the three-dimensional microtomography, the dorsal wall was higher in density compared with the abaxial wall. The latter exhibited an intermediate density, while the sole showed the lowest density. The Vickers nanohardness test showed that there was no difference in hardness and resistance between the experienced regions. However, the elastic modulus was greater on the transversal section of the hoof capsule. In conclusion, the results of the current study show that modern technologies such as microtomography and subsequent imaging can be used to investigate details of the basic morphology in different regions of the buffalo's hoof.


Assuntos
Búfalos/anatomia & histologia , Casco e Garras/ultraestrutura , Animais , Dimetilaminas , Módulo de Elasticidade , Tomografia com Microscopia Eletrônica/veterinária , Feminino , Membro Anterior , Dureza , Membro Posterior , Casco e Garras/fisiologia , Imageamento Tridimensional/veterinária , Polímeros , Estireno , Inclusão do Tecido/veterinária
8.
Anat Histol Embryol ; 46(5): 456-463, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28857262

RESUMO

The aim of this study was to describe the microstructure of the pigmented and depigmented hoof capsule of Girolando cattle by bi- and tridimensional microtomography and nanoindentation, analysing the possible relation between these findings and the susceptibility of such animals to podal diseases. To carry out the microtomography and the nanoindentation, duplicated samples were collected from the dorsal wall, abaxial wall and pre-bulbar sole of the hoof capsule. Material collection was performed in 40 medial digits of thoracic limbs and 40 lateral digits of pelvic limbs. The bidimensional microtomography showed that the dorsal wall of the thoracic and pelvic limbs presented higher density, followed by the abaxial wall, and finally by the sole, with the lowest density. Moreover, the hoof capsule of cows of Girolando breed is a compact, non-porous material, and constituted by extratubular and intratubular keratin. By the tridimensional microtomography, it was possible to measure the angles of the corneal tubules in relation to the periople and the claws in the different regions of the hoof capsule, which were 90° for the dorsal wall, 55° for the abaxial wall and 70° for the sole. The tridimensional microtomography also showed corneal tubules of different diameters: 17, 51, 85, 119 and 153 µm. The nanoindentation test, when performed in different regions of the hoof capsule, did not reveal significant difference of Vickers hardness in the evaluated areas. However, we verified a larger elastic module of these regions on the transversal cut of the corneal tubules compared to the longitudinal cut.


Assuntos
Bovinos/anatomia & histologia , Casco e Garras/ultraestrutura , Animais , Elasticidade , Tomografia com Microscopia Eletrônica/veterinária , Membro Anterior , Testes de Dureza , Membro Posterior , Casco e Garras/anatomia & histologia , Casco e Garras/química , Imageamento Tridimensional/veterinária , Queratinas/química , Nanoestruturas , Pigmentação
9.
Endocrinology ; 138(12): 5325-32, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9389517

RESUMO

Uncoupling protein-1 (UCP) is uniquely expressed in brown adipose tissue (BAT) and is essential to the thermogenic function of this tissue. The UCP gene is under the control of norepinephrine (NE) via cAMP. However, the precise delineation of the cAMP response sequences and mechanisms whereby cAMP stimulate the gene have remained elusive. A BAT tumor cell line, HIB-1B, can be differentiated into UCP-expressing brown adipocytes. We report here that when these cells are differentiated with a standard differentiation protocol including insulin, T3, hydrocortisone, IBMX, and indomethacin (standard differentiation, StD), cAMP stimulation of the rat UCP gene is largely mediated by an upstream 90-bp sequence -2,399/-2,490 (R90) with a lesser contribution of a downstream sequence -57/+114 (dnCRS). This latter is functional also in non-BAT cells, whereas the cAMP response sequence contained in R90 (upCRS) is BAT-specific. Thiazolidinediones (TZD) are a new group of drugs known to increase sensitivity to insulin and, more recently, to induce adipocyte differentiation (adipogenesis) via PPARgamma. A TZD, darglitazone (darg), can rapidly induce differentiation of HIB-1B cells, as judged by the expression of the adipocyte lipid binding protein (aP2), lipoprotein lipase (LPL), uncoupling protein (UCP) and beta3-adrenergic receptors. UCP messenger RNA (mRNA) responsive to NE is evidenced as early as one day after exposure to darg. While UCP-CAT vectors (+114/-3673 bp of rat UCP gene) are barely responsive to NE in HIB-1B preadipocytes, both darg and StD markedly enhance NE responsiveness of such constructs. However, by 3 days of exposure to darg, the responses were less vigorous than in StD cells (4- to 10-fold vs. 20- to 50-fold), and the deletion of R90 did not affect the response to NE in darg-differentiated cells, whereas this deletion caused a 75% reduction in StD cells. Prolongation of darg exposure to 5-7 days resulted in greater response of UCP mRNA to NE and 50-80% inhibition of the response of UCP-CAT vectors by the deletion of R90. Thus, darg-induced differentiation of HIB-1B cells suggests that the NE-dependent expression of the UCP gene takes place in a step-wise manner: first, the gene is "enabled," as no UCP mRNA is detected in HIB-1B preadipocytes; thereafter and transiently, the response of the gene to NE is sustained by dnCRS; finally, as differentiation progresses, a cell-specific and more powerful cis-acting sequence, upCRS, is recruited, accounting in the fully differentiated cell for most of the response to NE. These results also suggest that TZDs might increase energy expenditure by inducing terminal differentiation of BAT, and that these drugs may be useful in the differential cloning of the factors involved in the recruitment of the BAT specific cAMP response sequence.


Assuntos
Adipócitos/citologia , Tecido Adiposo Marrom/citologia , Proteínas de Transporte/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Membrana/genética , Tiazóis/farmacologia , Tiazolidinedionas , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Sequência de Bases , Proteínas de Transporte/metabolismo , Diferenciação Celular/fisiologia , Canais Iônicos , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Mitocondriais , Norepinefrina/farmacologia , Ratos , Células Tumorais Cultivadas , Proteína Desacopladora 1
10.
Endocrinology ; 136(3): 1003-13, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7867554

RESUMO

Uncoupling protein (UCP) is essential to brown adipose tissue (BAT) thermogenesis and, hence, to cold adaptation and energy balance. The sympathetic nervous system, via norepinephrine and cAMP, and thyroid hormone seem to be the major regulators of UCP expression. T3 potentiates the effect of norepinephrine and is essential for the adaptive response of this protein to cold. The goal of the present studies was to investigate whether T3 directly stimulates the transcription of the rat UCP gene, as suggested by in vivo results, and if so, to identify and characterize the sequences involved. We examined the gene sequence between 114 and -3623 by transient transfection analysis in JEG-3 and HIB-1B cells, a BAT-derived cell line. This 3.7-kilobase UCP insert makes the reporter gene responsive to cAMP (4-fold), T3 (4-fold), or both combined (12-fold). We identified an 82-basepair (bp) restriction fragment between -2317 and -2399, which we called thyroid hormone response sequence (THRS), that conferred T3 responsiveness to the UCP minimal promoter (4- to 12-fold) as well as to the thymidine kinase promoter (3- to 6-fold). T3 receptor bound to THRS in vitro, retarding its migration in electrophoretic mobility shift assays. Footprinting of THRS revealed two potential thyroid hormone response elements (TRE) separated by 27 bp: upTRE, -2391/-2376, 5'ACCCCTACTGAGGCAA; and dnTRE, -2348/-2334, 5'AGGGCAGCAAGGTCA. The mutation of these putative TREs caused loss of both T3 receptor binding and transactivation by T3. The analysis of the mutants also demonstrated that both TREs contribute in similar proportion to the T3 responsiveness of the UCP gene and that dnTRE is necessary for the potentiation of the cAMP effect by T3. Both TREs are located within a previously identified 212-bp enhancer element, flanked by sequences considered essential for BAT expression and norepinephrine responsiveness. Although they do not mediate thyroid hormone responsiveness, the sequences flanking THRS increase basal reporter expression and enhance the responses to T3. In conclusion, our results indicate that T3 can stimulate the transcription of the UCP gene and amplify the effect of cAMP acting directly on the gene. The presence of two functional TREs in a location critical to the control of the gene supports the importance of thyroid hormone for its expression and suggests the potential for interactions at the gene level that may explain the complexity of UCP regulation in vivo.


Assuntos
Proteínas de Transporte/genética , Elementos Facilitadores Genéticos , Genes , Proteínas de Membrana/genética , Hormônios Tireóideos/farmacologia , Animais , Sequência de Bases , Linhagem Celular , Humanos , Canais Iônicos , Lipoma/genética , Lipoma/patologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Dados de Sequência Molecular , Mutação , Placenta/citologia , Ratos , Receptores dos Hormônios Tireóideos/metabolismo , Ativação Transcricional , Transfecção , Tri-Iodotironina/metabolismo , Células Tumorais Cultivadas , Proteína Desacopladora 1
11.
Endocrinology ; 137(8): 3478-87, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8754777

RESUMO

Uncoupling protein (UCP) is essential to the thermogenic function of brown adipose tissue (BAT). Thyroid hormone stimulates the rat UCP gene through two thyroid hormone response elements (TRE) located upstream of -2,300 and separated by 27 bp. They are an everted repeat (upstream TRE or upTRE) and a direct repeat (down-stream TRE or dnTRE). The goal of the present studies was to investigate whether these TREs interact and how such an interaction could contribute to explain the UCP responsiveness to T3 in vivo. We therefore aimed to define: the heterodimeric partner of the T3 receptor (T3R); the role of T3 in the receptor-receptor and receptors-DNA interactions; how such in vitro interactions relate to the enhancer function of TREs; and how the two TREs interact. Studies included electrophoretic mobility shift assays, utilizing T3R and retinoid X receptors (RXR); DNA footprinting; and transient transfections of HIB-1B cells, a BAT-derived cell line. As in many previously described TREs, the partner of the T3R is RXR. The unliganded T3Rs bind to the TREs as homodimers, which act as repressors of transcription. T3 reduces the binding of T3R homodimers, hence relieving the repression, and stimulates the binding of heterodimers and transcription in proportion to the heterodimer binding to the elements. Although qualitatively similar in these regards, there were important quantitative differences between both TREs. The upTRE binds more T3R homodimers and less T3R-RXR heterodimers than the dnTRE, and T3 more readily facilitates heterodimer binding to the dn- than to the upTRE. These in vitro characteristics are reflected in a lower efficiency of T3 to relieve T3R homodimer-mediated repression and to stimulate transcription through up-than through dnTRE. There were also significant interactions between the two TREs both in the binding of the receptors, T3R and RXR, and in the responsiveness to T3. By itself, each TRE responded modestly to T3, upTRE with lower sensitivity and dnTRE with higher sensitivity than traditional TREs, whereas together, in the context of the gene sequence, they mediated a response greater than the sum of those mediated by each TRE separately, with an intermediate sensitivity to T3. Thus, two TREs that are inadequate to explain the responsiveness of the UCP gene to T3, together form a complex unit appropriate for the regulation of the gene by thyroid hormone. These interactions represent yet another way TREs can shape up the responsiveness of genes to thyroid hormone.


Assuntos
Proteínas de Transporte/genética , Expressão Gênica , Genes/fisiologia , Proteínas de Membrana/genética , Ratos/genética , Receptores do Ácido Retinoico/fisiologia , Receptores dos Hormônios Tireóideos/fisiologia , Fatores de Transcrição/fisiologia , Tri-Iodotironina/fisiologia , Adipócitos/fisiologia , Tecido Adiposo Marrom/citologia , Animais , Sequência de Bases , Células Cultivadas , Proteínas de Ligação a DNA/fisiologia , Genes/efeitos dos fármacos , Canais Iônicos , Ligantes , Proteínas Mitocondriais , Sondas Moleculares/genética , Dados de Sequência Molecular , Receptores X de Retinoides , Ativação Transcricional , Proteína Desacopladora 1
12.
Endocrinology ; 137(8): 3488-96, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8754778

RESUMO

Retinoids have been implicated in the control of cell proliferation and differentiation, and in several developmental processes. We report here the molecular bases for a metabolic role of RA, by showing that the expression of the uncoupling protein (UCP), the key element in brown adipose tissue (BAT) thermogenesis, is stimulated by retinoic acid (RA). Both all-trans-RA and 9-cis-RA powerfully increase UCP messenger RNA levels in isolated rat brown adipocytes. Transient transfection experiments in HIB-1B cells, a BAT-derived cell line, identified the sequence -2399/-2490 (called R90) as the RA-responsive sequence in the rat UCP gene. R90 mediated a 20- to 70-fold stimulation of the chloramphenicol acetyl transferase reporter gene by maximal concentrations of all-trans-RA or 9-cis-RA. Non-BAT cells were significantly less responsive. RA effect was also less when chloramphenicol acetyl transferase gene was driven by a heterologous promoter instead of the UCP minimal promoter. By footprinting and site-directed mutagenesis, we identified three discrete sequences as being essential for the RA response within R90, thus defining the complex RA response element (RARE) of this gene. Critical bases in these sequences are arranged in pairs of putative half-sites. RAR gamma-RXR heterodimers can bind to the R90 as revealed by electrophoretic mobility shift assays using in vitro translated receptors, and HIB-1B nuclear extracts with anti-RAR gamma or anti-RXR antibodies. The participation of RAR gamma-RXR heterodimers in RA stimulation is further supported by transient transfection experiments overexpressing selected receptors and dose-response analyses of RA isomers and analogues. These results show that retinoids strongly stimulate the rat UCP gene expression through a complex RARE, composed of three pairs of half-sites, and define a novel role for retinoids in the regulation of facultative thermogenesis and energy expenditure.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Proteínas de Transporte/genética , Genes/efeitos dos fármacos , Proteínas de Membrana/genética , Retinoides/metabolismo , Tretinoína/farmacologia , Adipócitos/efeitos dos fármacos , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/efeitos dos fármacos , Animais , Células Cultivadas , Canais Iônicos , Proteínas Mitocondriais , Ratos , Receptores do Ácido Retinoico/fisiologia , Proteína Desacopladora 1
13.
Endocrinology ; 139(1): 428-31, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9421444

RESUMO

Thiazolidinediones (TZD) are PPAR gamma ligands that sensitize tissues to insulin. A cDNA encoding a mitochondrial protein likely to act as uncoupler (uncoupling protein 2, UCP2) has been recently cloned. Since TZD have been reported to increase energy expenditure in animals, we have examined the effects of these drugs on the expression of UCP2 mRNA in cell lines representing white (3T3-L1 and 3T3-F442A) and brown (HIB-1B) adipose tissues and skeletal muscle (L6). Northern blots probed with a mouse UCP2 full-length cDNA showed a mRNA of 1.6 kb both in tissues and the aforementioned cells lines. Within 4 h of exposing these cells to 30 microM darglitazone, there was an increase in UCP2 mRNA which reached a plateau of 5-10 times the basal in about 8 h. In all cells TZDs (darglitazone, troglitazone) were more active than the predominantly PPAR alpha ligands WY-14,613 and clofibrate, or the non-selective ligand linoleic acid. These results indicate that TZDs can stimulate the expression of UCP2 gene probably via PPAR gamma and hence have the potential to increase energy expenditure in adult humans, in whom UCP2 is expressed ubiquitously.


Assuntos
Tecido Adiposo/metabolismo , Cromanos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Proteínas de Membrana Transportadoras , Proteínas Mitocondriais , Músculo Esquelético/metabolismo , Proteínas/genética , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Linhagem Celular , Resistência à Insulina , Canais Iônicos , Camundongos , Ratos , Receptores Citoplasmáticos e Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Troglitazona , Proteína Desacopladora 2
14.
Endocrinology ; 139(2): 571-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9449627

RESUMO

In euthyroid rats, maximal sympathetic nervous system stimulation (e.g. during cold exposure) results in a 3- to 4-fold increase in brown adipose tissue lipogenesis, a response that is blunted in hypothyroid rats. To further investigate this phenomenon, the role of local type II 5'-deiodinase (5'-DII) was studied in freshly isolated brown adipocytes. In a typical experiment, 1.5 x 10(6) cells were incubated for up to 48 h in a water-saturated 5% CO2-95% O2 atmosphere. After incubation with medium alone or with different concentrations of T4, T3, and/or norepinephrine (NE), lipogenesis was studied by measuring 1) the rate of fatty acid synthesis as reflected by 3H2O incorporation into lipids and 2) the activity of key rate-limiting enzymes, i.e. acetyl coenzyme A carboxylase and malic enzyme, and the results are reported in terms of DNA content per tube. Lipogenesis decreased progressively over time (approximately 40%) when no additions were made to the incubation medium. T4 or T3 partially prevented that inhibition at physiological concentrations (65 x 10[-9] and 0.77 x 10[-9] M, respectively), whereas a receptor-saturating concentration of T3, (154 x 10[-9] M) doubled the lipogenesis rate. The addition of 10(-6) M NE inhibited lipogenesis acutely (approximately 50% by 12 h) and was followed by a progressive stimulation that reached approximately 2-fold by 48 h, but only in the presence of T4. Furthermore, NE did not attenuate T3 (154 x 10[-9] M)-induced lipogenesis. Both the inhibition and the stimulation of lipogenesis caused by NE showed a strong dose-response relationship within the range of 10(-11)-10(-5) M. The role of local 5'-DII was further tested by incubating brown adipocytes with 10(-6) M NE and T4 (65 x 10[-9] M) in the presence of 100 microM iopanoic acid, a potent inhibitor of 5'-DII. Although iopanoic acid did not affect the T3 stimulation of lipogenesis, it did block the approximately 2-fold stimulation of lipogenesis triggered by NE in the presence of T4, confirming the mediation of 5'-DII in this process. In conclusion, lipogenesis in brown adipose tissue is under complex hormonal control, with key roles played by NE, thyroid hormones, and local 5'-DII. As in other tissues, NE-generated signals acutely (12 h) inhibited lipogenesis. However, the presence of the 5'-DII generated enough T3 to stimulate lipogenesis and gradually reverse the short-lived NE-induced inhibition, leading to the 2- to 3-fold response observed at later time points.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo Marrom/metabolismo , Iodeto Peroxidase/fisiologia , Lipídeos/biossíntese , Norepinefrina/farmacologia , Tecido Adiposo Marrom/citologia , Animais , Técnicas Citológicas , Relação Dose-Resposta a Droga , Enzimas/metabolismo , Ácido Iopanoico/farmacologia , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
15.
Mol Cell Endocrinol ; 165(1-2): 7-15, 2000 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-10940478

RESUMO

Glucocorticoids may inhibit brown adipose tissue (BAT) thermogenesis acting at a central level as well as reducing the responses of the tissue to adrenergic stimulation in vivo. This latter effect is not well understood. We investigated whether or not glucocorticoids directly reduce the expression of the key molecule for BAT thermogenesis, uncoupling protein-1 (UCP1), and if so, to what extent and by what mechanisms. We used HIB-1B brown adipose cells obtained from a hibernoma. The response of UCP1 mRNA to adrenergic stimulation in these cells is qualitatively and quantitatively similar to that seen in vivo. Dexamethasone and other glucocorticoids, given simultaneously with NE, nearly abolish the ensuing UCP1 mRNA accumulation. This effect was negated by the glucocorticoid receptor antagonist RU-486. Significant inhibition is seen within the physiological range of concentrations, with ID(50)s for dexamethasone and corticosterone of 1 and 75 nM, respectively. Within the time span of the experiments, glucocorticoids did not reduce the strength of the NE signal nor did they necessitate ongoing protein synthesis or reduce the stability of mature UCP1 mRNA, but they significantly inhibited the stimulation of transcription by NE in a run-on in vitro transcription assay. These observations indicate that glucocorticoids are powerful inhibitors of the UCP1 gene response to adrenergic stimulation acting at transcriptional level, and provide further evidence for a global inhibitory effect of glucocorticoids on BAT thermogenesis.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Proteínas de Transporte/genética , Glucocorticoides/farmacologia , Proteínas de Membrana/genética , Norepinefrina/farmacologia , Animais , Sequência de Bases , Linhagem Celular , Corticosterona/farmacologia , Primers do DNA/genética , Dexametasona/farmacologia , Canais Iônicos , Camundongos , Proteínas Mitocondriais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Termogênese/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Proteína Desacopladora 1
16.
Eur J Endocrinol ; 136(3): 251-64, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9100546

RESUMO

Uncoupling protein (UCP) is essential to the thermogenic function of brown adipose tissue (BAT). The thermogenic role of this protein is due to its capacity to uncouple oxidative phosphorylation in a regulated manner. The thermogenic potential of BAT is determined by its content of UCP. The gene encoding this protein is under complex regulation. Catecholamines, via cAMP, thyroid hormone and retinoic acid, directly stimulate the gene acting upon an upstream (-2.28/-2.49 kb) enhancer sequence, but cAMP may act upon other sequences of the gene as well. CCAAT enhancer binding proteins and peroxisome proliferation activator receptor (PPAR) gamma 2 have also been implicated in the regulation of the gene acting on discrete sequences. While the thyroid hormone response and retinoic acid response elements (TRE and RARE) have been well defined, the cAMP response elements (CRE) remain elusive. The two TREs are 27 bp apart between -2.33 kb and -2.39 kb. The synergism between cAMP and thyroid hormone seems to reside in a 39 bp sequence downstream (-2.28/-2.32 kb). The most important CRE, the RARE, a cell-specific enhancer and a putative PPAR element are all concentrated in a 90 bp regulatory element of great complexity (-2.40/-2.49 kb). Other hormones, such as insulin and glucocorticoids, and IGF-I also modulate the expression of the gene but their effects seem to be largely indirect. Understanding the regulation of the UCP gene expression may facilitate the development of interventions in obesity and related disorders.


Assuntos
Proteínas de Transporte/genética , Regulação da Expressão Gênica , Proteínas de Membrana/genética , Animais , Sequência de Bases , AMP Cíclico/fisiologia , Humanos , Canais Iônicos , Proteínas Mitocondriais , Dados de Sequência Molecular , Sistema Nervoso Simpático/fisiologia , Hormônios Tireóideos/fisiologia , Tretinoína/fisiologia , Proteína Desacopladora 1
17.
Ann N Y Acad Sci ; 1026: 273-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15604505

RESUMO

The effectiveness of combining metacresolsufonic acid with streptomycin in the treatment of actinomycosis, diagnosed either clinically or in the laboratory, was evaluated in 12 bovines and 2 equines. Eighty-seven percent of treated animals were considered clinically cured and did not show any signs of relapse after a six-month follow-up period. Therapeutic diagnosis by clinical observation was the procedure of choice when it was not possible to obtain laboratory diagnosis.


Assuntos
Actinomicose/tratamento farmacológico , Antibióticos Antineoplásicos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Cresóis/uso terapêutico , Formaldeído/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico , Estreptozocina/uso terapêutico , Animais , Antibióticos Antineoplásicos/administração & dosagem , Bovinos , Cresóis/administração & dosagem , Combinação de Medicamentos , Quimioterapia Combinada , Formaldeído/administração & dosagem , Cavalos , Estreptozocina/administração & dosagem , Resultado do Tratamento
18.
Ann Thorac Surg ; 60(2 Suppl): S316-21, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7646180

RESUMO

We propose the use of a crimped bovine pericardial graft joined to a rigid and grooved ring for the treatment of aortic dissections and aneurysms. This device was developed to support common tubular vascular prostheses of any material, length, diameter, or form, transforming them into intraluminal ones during the surgical procedure. During March 1989 to May 1994, 74 patients underwent an operation on the aorta in which this intraluminal ring, prepared from a tubular prosthesis of bovine pericardium, was used. Twenty-seven patients had an acute type A aortic dissection, 6 had an acute type B aortic dissection, 10 had annuloaortic ectasia, 6 had a descending aortic aneurysm, 3 had a thoracoabdominal aneurysm, and 22 had an abdominal aneurysm. The global mortality rate of 10.8% in the immediate postoperative period cannot be related to the surgical technique or the type of prosthesis used. We conclude from our findings that this modification of the sutureless intraluminal graft, which allows it to be used to replace diseased segments of the aorta, affords the quickest and simplest means of repair and is attended by the least likelihood of anastomotic complications.


Assuntos
Aorta/cirurgia , Bioprótese , Prótese Vascular , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/cirurgia , Animais , Aneurisma Aórtico/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Ovinos
19.
Arq Neuropsiquiatr ; 58(3A): 621-4, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10973100

RESUMO

With the aim to study the magnitude of infection by the metacestode of Taenia solium in a population of epileptic patients in the arid region of Bahia, Northeastern Brazil, we examined 200 consecutive cases who attended an ambulatory clinic in the disctrict of Mulungu do Morro. Sixty-six of the patients had a diagnosis of epilepsy. From them 10 (15.2%) presented antibodies against a specific fraction of antigens in Western blot, and 4 (6.0%) had circulating parasite products, as tested by capture ELISA. Only 1 case was positive for antibodies and antigens. We found that the frequency of seropositivity was related to the time without epileptic seizure. We conclude that cysticercosis is endemic in the region of Mulungu do Morro and that it is related to a benign form of epilepsy.


Assuntos
Cisticercose/epidemiologia , Doenças Endêmicas , Epilepsia/parasitologia , Adolescente , Adulto , Anticorpos Anti-Helmínticos , Western Blotting , Brasil/epidemiologia , Criança , Cisticercose/complicações , Cisticercose/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurocisticercose/complicações , Neurocisticercose/epidemiologia , Áreas de Pobreza , Prevalência
20.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 811-818, May-June 2019. tab, ilus
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1011292

RESUMO

Trauma or disease inflicted by tissue injuries may cause tissue degeneration. The use of biomaterials for direct or indirect repair has emerged as a promising alternative, and has become an important research topic. The pequi fruit (Caryocar brasiliense Camb.) has shown antifungal, antibacterial, anti-inflammatory, healing, antitumor, and antioxidant properties. The objective of this study was to develop a new biomaterial using a combination of collagen, gelatin, and pulp pequi oil, and to evaluate its biocompatibility in comparison with that of biomaterials produced without pulp pequi oil. Membranes were prepared from a mixture of bovine tendon collagen, commercial gelatin, and pulp pequi oil. The inflammatory and cicatricial processes were assessed via histopathology of the tissue interface/implants in the subcutaneous tissues and quantitative evaluation of leukocyte and collagen production in Wistar rats. It was observed that the presence of pequi oil reduced the amount of foreign-body giant cells and favored the recruitment of fibroblasts (P< 0.01), thereby promoting greater production of collagen membrane than that in the membranes of control samples. Therefore, it can be concluded that the addition of pequi oil improved the biocompatibility of collagen and accelerated the healing process.(AU)


Trauma ou lesões causadas por doenças podem enfraquecer e degenerar os tecidos humanos e animais. O uso de biomateriais para reparação direta ou indireta surgiu como uma alternativa promissora e tornou-se um importante tema de pesquisa. O óleo de pequi (Caryocar brasiliense Camb.) mostrou propriedades antifúngicas, antibacterianas, anti-inflamatórias, curativas, antitumorais e antioxidantes. O objetivo deste estudo foi obter um novo biomaterial, produzido pela combinação de óleo de pequi, colágeno e gelatina, para avaliar sua biocompatibilidade em comparação às membranas produzidas sem o óleo. As membranas foram preparadas por meio da mistura de colágeno de tendão bovino, gelatina comercial e óleo de pequi. Os processos inflamatórios e cicatriciais foram avaliados por histopatologia da interface / implantes de tecido subcutâneo de ratos Wistar para avaliação quantitativa da produção de leucócitos e colágeno. Observou-se que a presença de óleo de pequi reduziu a quantidade de células gigantes de corpo estranho e favoreceu o recrutamento de fibroblastos (P<0,01), promovendo, assim, maior produção da membrana de colágeno em comparação com a membrana de controle. Portanto, pode-se concluir que a adição de óleo de pequi melhorou a biocompatibilidade do colágeno e acelerou o processo de cicatrização.(AU)


Assuntos
Animais , Ratos , Materiais Biocompatíveis/uso terapêutico , Lesões dos Tecidos Moles/veterinária , Ericales , Cicatrização , Colágeno/uso terapêutico , Gelatina/uso terapêutico
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