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1.
Phys Rev E ; 110(2-1): 024130, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39294996

RESUMEN

Recently, a kind of finite-temperature pseudotransition was observed in several quasi-one-dimensional models. In this work, we consider a genuine one-dimensional extended Hubbard model in the atomic limit, influenced by an external magnetic field and with the arbitrary number of particles controlled by the chemical potential. The one-dimensional extended Hubbard model in the atomic limit was initially studied in the seventies and has been investigated over the past decades, but it still surprises us today with its fascinating properties. We rigorously analyze its low-temperature behavior using the transfer matrix technique and provide accurate numerical results. Our analysis confirms that there is an anomalous behavior in the half-filled band, specifically occurring between the alternating pair (AP) and paramagnetic (PM) phases at zero temperature. Previous investigations did not deeply identify this anomalous behavior, maybe due to the numerical simplicity of the model, but from an analytical point of view this is not so easy to manipulate algebraically because one needs to solve an algebraic cubic equation. In this study, we explore this behavior and clearly distinguish the pseudotransition, which could easily be mistaken with a real phase transition. This anomalous behavior mimics features of both first- and second-order phase transitions. However, due to its nature, we cannot expect a finite-temperature phase transition in this model.

2.
Phys Rev E ; 107(1-1): 014141, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36797920

RESUMEN

Ground-state and magnetocaloric properties of a site-diluted sawtooth magnetic chain in the presence of an external magnetic field are exactly investigated by using the transfer-matrix method. The model captures the main magnetic interactions along CuO chains present in some hole-doped cuprates. The ground-state diagram is exhibited and analytical expressions for the residual entropy within each ground state and along the transition lines are derived. We explicitly discuss the role of the underlying pairing correlations and the entropy maximization principle. The isothermal entropy change is determined as a function of interaction parameters, doping concentration, and magnetic-field amplitude. Normal and inverse magnetocaloric effects are reported. Adiabatic demagnetization curves are discussed in connection with configurational and spin contributions to the residual entropy.

3.
Phys Rev E ; 103(4-1): 042123, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34006009

RESUMEN

We consider the extended Hubbard diamond chain with an arbitrary number of particles driven by chemical potential. The interaction between dimer diamond chain and nodal couplings is considered in the atomic limit (no hopping), whereas the dimer interaction includes the hopping term. We demonstrate that this model exhibits a pseudo-transition effect in the low-temperature regime. Here, we explore the pseudo-transition rigorously by analyzing several physical quantities. The internal energy and entropy depict sudden, although continuous, jumps which closely resembles discontinuous or first-order phase-transition. At the same time, the correlation length and specific heat exhibit astonishing strong sharp peaks quite similar to a second-order phase-transition. We associate the ascending and descending parts of the peak with power-law "pseudo-critical" exponents. We determine the pseudo-critical exponents in the temperature range where these peaks are developed, namely, ν=1 for the correlation length and α=3 for the specific heat. We also study the behavior of the electron density and isothermal compressibility around the pseudo-critical temperature.

4.
Folia Morphol (Warsz) ; 79(1): 168-171, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31063200

RESUMEN

The giant armadillo (Priodontes maximus) is found in diverse habitats from South America. A female adult giant armadillo with a body mass of 45 kg was used. The animal was a victim of trampling on highway AC-40, at 70 km, near the municipality of Capixaba-Acre and the corpse donated to the Animal Anatomy Laboratory at Federal University of Acre (UFAC). The arterial system was filled with natural latex via the thoracic aorta in a direction opposite the blood flow to facilitate the description of the aortic arch and its side branches. The study was approved by CEUA/UFAC - no. 053/2015 and SISBIO no. 47124-1. The aortic arch issued side groups, which had the following sequence: brachycephalic trunk, left carotid artery, left subclavian artery. The brachycephalic trunk forked forming the right subclavian artery and the right common carotid artery. The arrangement allowed the whole carotid blood supply to the brain and surrounding structures present in the animal's head. The subclavian arteries, of homologous way, originated the arteries: vertebral, thoracic, and cervical costocervical trunk. The aortic arch armadillo showed the same pattern as that described for the Euphractus sexcinctus and different from those reported for the Dasypus novemcinctus and Tamandua tetradactyla. In addition, the function assigned to each branch was the same regardless of the species with which it was compared.


Asunto(s)
Aorta Torácica/anatomía & histología , Armadillos/anatomía & histología , Animales , Femenino
5.
J Phys Condens Matter ; 32(3): 035804, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31581138

RESUMEN

Recently, it has been rigorously verified that several one-dimensional (1D) spin models may exhibit a peculiar pseudo-transition accompanied with anomalous response of thermodynamic quantities in a close vicinity of pseudo-critical temperature. In the present work we will introduce and exactly solve a mixed spin-(1/2,1) Ising-Heisenberg double-tetrahedral chain in an external magnetic field as another particular example of 1D lattice-statistical model with short-range interactions that displays a pseudo-transition of this type. The investigated model exhibits at zero temperature three ferrimagnetic phases, three frustrated phases, and one saturated paramagnetic phase. The ground-state phase diagram involves five unusual interfaces (phase boundaries), at which the residual entropy per site equals to a larger entropy of one of two coexisting phases. Four such interfaces are between a non-degenerate ferrimagnetic phase and a macroscopically degenerate frustrated phase, while one interface is between two non-degenerate ferrimagnetic phases. Though thermal excitations typically destroy all fingerprints of zero-temperature phase transitions of 1D lattice-statistical models with short-range forces, the mixed spin-(1/2,1) Ising-Heisenberg double-tetrahedral chain is quite robust with respect to thermal excitations and it displays peculiar pseudo-transitions close to all five aforementioned interfaces.

6.
Rev. argent. reumatol ; 30(1): 4-9, mar. 2019. ilus, tab
Artículo en Español | LILACS | ID: biblio-1013375

RESUMEN

Objetivo: Actualizar los resultados del registro BIOBADASAR sobre seguridad, duración y causas de interrupción del tratamiento luego de 8 años de seguimiento. Métodos: BIOBADASAR es un registro de seguridad de terapias biológicas establecido por la Sociedad Argentina de Reumatología. Se presenta la descripción de BIOBADASAR 3.0, una cohorte compuesta por 53 centros de Argentina seguidos prospectivamente desde agosto de 2010 hasta enero de 2018. Resultados: Se registraron 4656 pacientes, 6234 tratamientos [3765 casos (terapia con biológicos) y 2469 controles (terapia no biológicos)]. Se interrumpió el tratamiento en el 44,6% en los casos vs. 27,9% en los controles. Causa principal de discontinuación fue por ineficacia (40% casos vs. 32% controles). Se presentaron 3154 eventos adversos (2230 en casos vs. 924 en controles), de los cuales el 13,6% fueron graves (9,8% en casos y 3,7% en controles). El evento adverso (EA) más frecuente en ambos grupos fueron las infecciones (43,56% en casos vs. 34,31% en los controles, RR: 3,42; IC 95%: 3,02-3,88), y de ellas las de vías aéreas superiores (14,5%). Las neoplasias se presentaron en 78 casos vs. 45 en controles (RR: 1,98; IC 95%: 1,37-2,86). Conclusiones: En este sexto reporte no se observan tendencias diferentes sobre seguridad, duración y causas de interrupción del tratamiento respecto a informes previos. Las infecciones fueron el principal EA y la ineficacia, seguido por EA y la pérdida de pacientes las principales causas de suspensión del tratamiento. El advenimiento de nuevos agentes biológicos y la necesidad de control en seguridad a largo plazo, fortalece el uso de este tipo de registro.


Objective: Update the results of the BIOBADASAR registry on safety, duration and causes of treatment interruption after 8 years of follow-up. Methods: BIOBADASAR is a safety record of biological therapies established by the Argentine Society of Rheumatology. The description of BIOBADASAR 3.0 is presented, a cohort of 53 centers in Argentina followed prospectively from August 2010 to January 2018. Results: 4656 patients were registered, 6234 treatments [3765 cases (therapy with biologicals) and 2469 controls (non-biological therapy)]. Treatment was interrupted in 44.6% in cases vs. 27.9% in controls. Main cause of discontinuation was due to inefficiency (40% cases vs. 32% controls). There were 3154 adverse events (2230 in cases vs. 924 in controls), of which 13.6% were tombs (9.8% in cases and 3.7% in controls). The most frequent adverse event (AE) in both groups were infections (43.56% in cases vs. 34.31% in controls, RR: 3.42, 95% CI: 3.02-3.88), and the upper airway pathways (14.5%). Neoplasms were published in 78 cases versus 45 controls (RR: 1.98, 95% CI: 1.37-2.86). Conclusions: In this article, there are no different trends regarding safety, duration and causes of interruption of treatment compared to previous reports. Infections were the main causes of treatment discontinuation. The advent of new biological agents and the need for control over long-term security, strengthens the use of this type of registration.


Asunto(s)
Terapéutica , Factores Biológicos , Informe de Investigación
7.
Med Mycol ; 56(4): 485-492, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29420782

RESUMEN

Pythium insidiosum is an important aquatic Oomycota that causes pythiosis in mammals, especially horses, dogs, and humans; these inhabit marshy environments in tropical and subtropical areas. The aim of this study was to determine the protein profile, as well as identify likely immunodominant proteins, of Brazilian P. insidiosum isolates from southern Brazil, an important equine pythiosis endemic area. P. insidiosum isolates (horses, n = 20 and dogs, n = 02) were analyzed by SDS-PAGE and Western blot techniques. Horse, cattle, dog, and rabbit sera of both diseased and healthy animals were used to identify P. insidiosum proteins. SDS-PAGE protein profile detected antigens of molecular weights ranging from 100 to 20 KDa. Dog isolates revealed a protein profile similar to that of horse isolates. Anti-P. insidiosum antibodies in the sera of the four species could recognize proteins of different molecular weights (∼74 KDa to ∼24 KDa), and proteins ∼50-55 KDa and ∼34 KDa were shown to be immunodominant. Furthermore, ∼74 KDa, ∼60 KDa, ∼30 KDa and ∼24 KDa proteins were poorly recognized by host species antibodies. The Brazilian P. insidiosum isolates analyzed showed a similar protein profile; however, further studies are essential for the identification and characterization of proteins expressed by P. insidiosum, and an evaluation of the immunological profile of hosts susceptible to this Oomycota is necessary.


Asunto(s)
Antígenos Fúngicos/análisis , Enfermedades de los Perros/microbiología , Proteínas Fúngicas/análisis , Enfermedades de los Caballos/microbiología , Pitiosis/microbiología , Pythium/metabolismo , Animales , Anticuerpos Antifúngicos/sangre , Perros , Femenino , Caballos , Epítopos Inmunodominantes , Masculino , Peso Molecular
8.
J Periodontal Res ; 52(4): 734-744, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28256038

RESUMEN

BACKGROUND AND OBJECTIVE: The potential benefits of statins in modulating periodontal disease is supported by in vitro and clinical studies showing statins can induce a lower expression of proinflammatory cytokines and matrix metalloproteinases. The aim of this study was to evaluate the effects of rosuvastatin (ST) on ligature-induced periodontitis in spontaneously hypertensive rats (SHR). MATERIAL AND METHODS: Fifty-four adult male rats were divided into three groups: SHR-C, SHR-L and SHR-L-ST (C, control; L, ligature groups). In the SHR-L-ST group, animals were treated with daily 2 mg/kg ST administration. In L groups, a ligature remained around mandibular first molars for 10 d. Each group was divided for killing at 10 or 21 d postoperatively. Microtomographic and histometric analyses were performed. Osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase assay and gene expression of 84 proinflammatory mediators by polymerase chain reaction array. RESULTS: The SHR-L-ST group showed reduced bone loss and attachment loss in comparison with the SHR-L group at both 10 and 21 d postoperatively (p < 0.05). ST decreased the amount of tartrate-resistant acid phosphatase-positive cells compared with the SHR-L group at both 10 and 21 d (p < 0.05). The SHR-L-ST group presented 14 genes differentially expressed when compared with SHR-L group, featuring a downregulated gene profile at 10 d. CONCLUSION: Statin therapy may promote a protective effect against alveolar bone and connective tissue attachment losses attributable to periodontitis in hypertensive rats through inflammatory gene profile modulation.


Asunto(s)
Periodontitis/tratamiento farmacológico , Ratas Endogámicas SHR , Rosuvastatina Cálcica/farmacología , Animales , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Expresión Génica , Ligadura , Masculino , Mandíbula , Osteoclastos/efectos de los fármacos , Periodontitis/diagnóstico por imagen , Reacción en Cadena de la Polimerasa , Ratas , Microtomografía por Rayos X
9.
Vet Pathol ; 54(2): 242-248, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27586238

RESUMEN

Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, which is further divided into subgenotypes (1a-1u and 2a-c). When persistent infection occurs, the calf will be immunotolerant to BVDV and possibly develop mucosal disease. This study describes an outbreak of BVDV-1d-induced mucosal disease lacking intestinal lesions. Eleven calves presented with anorexia, sialorrhea, lameness, recumbency, and death. Three calves were necropsied, showing ulceration of the interdigital skin and the oral and nasal mucosa; linear ulcers in the tongue, esophagus, and rumen; and rounded ulcers in the abomasum. Microscopically, mucosa and skin had superficial necrosis, with single-cell necrosis and vacuolation in epithelial cells, and severe parakeratosis. Immunohistochemistry (IHC) showed BVDV antigen in the cytoplasm of epithelial cells in skin and mucosa. All 11 dead calves were positive upon reverse transcription-polymerase chain reaction (RT-PCR) for the detection of Pestivirus along with another 11 live calves from the herd, which were positive again by RT-PCR and IHC after a 4-week interval. Sequencing of the 5' untranslated region and N-terminal protease showed that viruses from these 22 calves were homologous and of subgenotype BVDV-1d. Cytopathic BVDV was isolated from 8 of 11 dead calves, but only noncytopathic BVDV was isolated from the 11 live animals. The findings indicate that this was an outbreak of mucosal disease caused by BVDV-1d, with high morbidity, and lesions restricted to the upper alimentary system and skin and absent from intestine. Thus, the epidemiological and pathological features in this form of mucosal disease may be similar to vesicular diseases, including foot and mouth disease.


Asunto(s)
Diarrea Mucosa Bovina Viral/virología , Virus de la Diarrea Viral Bovina Tipo 1/clasificación , Brotes de Enfermedades/veterinaria , Intestinos/patología , Animales , Diarrea Mucosa Bovina Viral/patología , Bovinos
10.
Genet Mol Res ; 15(3)2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-27706624

RESUMEN

Endometriosis is a disease that affects 10 to 15% of the women of reproductive age. It is characterized by the presence of endometrial-like tissues outside of the uterus. Some definitions claim that the functional ectopic tissue is sensitive to the action of hormones. Severity of endometriosis is defined according to a system proposed by the American Society for Reproductive Medicine, which is based on laparoscopic findings. A large number of genetic polymorphisms has been reported for CYP1A1, the gene that is responsible for enzymes involved in stage I detoxification of xenobiotics; this gene is located at 15q22-24, and encodes an isoenzyme that catalyzes the oxidation of polycyclic aromatic hydrocarbons present in phenolic compounds and epoxides. The aim of this study was to analyze the frequency of the MspI polymorphism and its relation to endometriosis. We obtained peripheral blood samples from 52 women with endometriosis (confirmed by laparoscopy) as well as 42 women without endometriosis (control group). In the case group, the women were between 25 and 35 years of age; the age range was between 25 and 57 years old in the control group. Molecular analysis was performed by polymerase chain reaction. We found a significant association (P = 0.039) between the polymorphic allele m1 and endometriosis (32.70%). In conclusion, this study showed that the m1 polymorphism is associated with endometriosis, and that W1/m1 and m1/m1 polymorphisms are more frequently observed in patients with infertility and severe endometriosis.


Asunto(s)
Citocromo P-450 CYP1A1/genética , Desoxirribonucleasa HpaII/química , Endometriosis/genética , Infertilidad Femenina/genética , Polimorfismo de Longitud del Fragmento de Restricción , Adulto , Alelos , Estudios de Casos y Controles , Endometriosis/complicaciones , Endometriosis/diagnóstico , Endometriosis/patología , Femenino , Expresión Génica , Frecuencia de los Genes , Genotipo , Humanos , Infertilidad Femenina/complicaciones , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/patología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
11.
Bioprocess Biosyst Eng ; 39(9): 1441-54, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27174225

RESUMEN

In this study, kinetic parameters were determined for the biodegradation of BTX compounds in a fixed-bed reactor with immobilized biomass, fed with mono- and multicomponent systems. The parameter estimation was achieved through an algorithm using the finite volume method. Different kinetic models were evaluated. The Monod model proved to be suitable to predict the experimental data for the biodegradation individual BTX compound. In multicomponent systems, it was found that the presence of more than one compound tends to cause competitive inhibition. To identify the models that best fit the experimental data, a statistical analysis using the F test was applied. For the two- and three-component systems the presence of more than one compound tends to cause competitive inhibition. In this study, it was possible to predict kinetic parameters in mono- and multicomponent systems as well as different operation conditions for a fixed-bed reactor with immobilized biomass.


Asunto(s)
Benceno/metabolismo , Biodegradación Ambiental , Biomasa , Tolueno/metabolismo , Xilenos/metabolismo , Cinética , Modelos Teóricos
12.
J Parasitol ; 102(3): 385-7, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26761197

RESUMEN

The first record of Echinostoma (Trematoda: Echinostomatidae) in coprolites was from a mummified human body in Minas Gerais State, Brazil. The finding raised questions on this parasite's incidence in prehistoric populations and the natural hosts of each species in remote times. Echinostomes occur worldwide and, despite the wide range of hosts, there is no record of Echinostomatidae in felines in Brazil. This study reports the finding of Echinostomatidae eggs in felid coprolites in the Furna do Estrago Archaeological Site, located in Pernambuco State in the Brazilian semiarid. Despite the possibility of false parasitism, the finding expands the distribution of this Digenea in remote times and raises the hypothesis of other cases of echinostomiasis in pre-Colombian populations.


Asunto(s)
Echinostomatidae/aislamiento & purificación , Heces/parasitología , Felidae/parasitología , Fósiles/parasitología , Animales , Brasil , Humanos , Óvulo
13.
Neurogastroenterol Motil ; 28(1): 101-15, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26526599

RESUMEN

BACKGROUND: Cachexia is a significant problem in patients with cancer. The effect of cancer on interstitial cells of Cajal (ICC) and neurons of the gastrointestinal tract have not been studied previously. Although supplementation with L-glutamine 2% may have beneficial effects in cancer-related cachexia, and be protective of ICC in models of oxidative stress such as diabetes, its effects on ICC in cancer have also not been studied. METHODS: Twenty-eight male Wistar rats were divided into four groups: control (C), control supplemented with L-glutamine (CG), Walker 256 tumor (WT), and Walker 256 tumor supplemented with L-glutamine (WTG). Rats were implanted with tumor cells or injected with saline in the right flank. After 14 days, the jejunal tissues were collected and processed for immunohistochemical techniques including whole mounts and cryosections and Western blot analysis. KEY RESULTS: Tumor-bearing rats demonstrate reduced numbers of Myenteric ICC and deep muscular plexus ICC and yet increased Ano1 protein expression and enhanced ICC networks. In addition, there is more nNOS protein expressed in tumor-bearing rats compared to controls. L-glutamine treatment had a variety of effects on ICC that may be related to the disease state and the interaction of ICC and nNOS neurons. Regardless, L-glutamine reduced the size of tumors and also tumor-induced cachexia that was not due to altered food intake. CONCLUSIONS & INFERENCES: There are significant effects on ICC in the Walker 256 tumor model. Although supplementation with L-glutamine has differential and complex effects of ICC, it reduces tumor size and tumor-associated cachexia, which supports its beneficial therapeutic role in cancer.


Asunto(s)
Caquexia/metabolismo , Carcinoma 256 de Walker/metabolismo , Canales de Cloruro/efectos de los fármacos , Glutamina/farmacología , Células Intersticiales de Cajal/efectos de los fármacos , Yeyuno/efectos de los fármacos , Plexo Mientérico/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo I/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Anoctamina-1 , Western Blotting , Carcinoma 256 de Walker/patología , Canales de Cloruro/metabolismo , Inmunohistoquímica , Células Intersticiales de Cajal/metabolismo , Masculino , Plexo Mientérico/citología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ratas , Ratas Wistar , Carga Tumoral
14.
Rev. argent. reumatol ; 27(1): 14-24, 2016. tab
Artículo en Español | LILACS | ID: biblio-831276

RESUMEN

Introducción: El proyecto BIOBADASAR (Registro argentino deeventos adversos con tratamientos biológicos en reumatología)comenzó en agosto de 2010, para recabar información a largo plazosobre los eventos adversos en tratamientos biológicos en pacientescon enfermedades reumáticas en la práctica clínica cotidiana enArgentina.Pacientes y método: Se registraron datos de cada paciente,tratamientos y acontecimientos adversos relevantes o importantes.Los pacientes debían tener enfermedad diagnosticada y tratadacon un agente biológico. Cada caso se comparó con un control:un paciente con tratamiento no biológico con característicasdemográficas similares. Se analizaron los datos con análisis de lavarianza, con test de t de Student, Mann Whitney, test chi2, o testexacto de Fisher. El análisis de supervivencia de los tratamientoshasta su discontinuación o interrupción se realizó con el método deKaplan-Meier y test log-rank...


Background: BIOBADASAR (Argentine Registry of Adverse Eventsin Biological Treatments in Rheumatology) was started in August2010 to obtain long-term information of patients with rheumatic diseases,treatments and adverse events in everyday clinical practice.Patients and methods: Data on patients’ demographics,treatments and adverse events were collected. Patients had a diagnosisof a rheumatic disease and were treated with biological agent.To compare information, a control group was included, consisting ofpatients treated with similar demographic characteristics but treatedwith a non-biological agent. Data were analysed with Anova,Student´s t, Mann Whitney, chi2, Fisher´s exact tests, as appropriate.Survival analysis of treatments was performed with Kaplan-Meiercurves and log-rank test...


Asunto(s)
Tratamiento Biológico , Enfermedades Reumáticas , Reumatología
15.
J Dev Orig Health Dis ; 5(3): 219-28, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24901662

RESUMEN

This study investigated the effects of maternal separation on the feeding behavior of rats. A maternal separation model was used on postnatal day 1 (PND1), forming the following groups: in the maternal separation (MS) group, pups were separated from their mothers each day from PND1 to PND14, whereas in the control (C) group pups were kept with their mothers. Subgroups were formed to study the effects of light and darkness: control with dark and light exposure, female and male (CF and CM), and maternal separation with dark and light exposure, female and male (SDF, SDM, SLF and SLM). Female rats had higher caloric intake relative to body weight compared with male controls in the dark period only (CF=23.3±0.5 v. CM=18.2±0.7, P<0.001). Macronutrient feeding preferences were observed, with male rats exhibiting higher caloric intake from a protein diet as compared with female rats (CF=4.1±0.7, n=8 v. CM=7.0±0.5, n=8, P<0.05) and satiety development was not interrupted. Female rats had a higher adrenal weight as compared with male rats independently of experimental groups and exhibited a higher concentration of serum triglycerides (n=8, P<0.001). The study indicates possible phenotypic adjustments in the structure of feeding behavior promoted by maternal separation, especially in the dark cycle. The dissociation between the mother's presence and milk intake probably induces adjustments in feeding behavior during adulthood.


Asunto(s)
Preferencias Alimentarias/fisiología , Preferencias Alimentarias/psicología , Privación Materna , Saciedad/fisiología , Animales , Animales Recién Nacidos , Conducta Alimentaria/fisiología , Conducta Alimentaria/psicología , Femenino , Masculino , Embarazo , Ratas , Ratas Wistar
16.
Genet Mol Res ; 12(4): 4625-9, 2013 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-24222238

RESUMEN

What are the targets of natural selection remains a controversial issue in Biology. Here I propose the "Extended Fitness" hypothesis, in which extended phenotypes emerge as a link between individual and group selection. The basic premise of the extended fitness hypothesis is that extended phenotypes can be used by members of the same group since they are adapted to use them. Thus, extended phenotypes can also contribute to the fitness of members of the same species. Group selection emerges as a natural consequence of the shared use of extended phenotypes, which allow the evolutionary forces acting on individuals to become effective at the group level. The extended fitness hypothesis is supported by several observations found in nature. The hypothesis presented here provides a theoretical framework for the design of both modeling and experimental approaches to studying the role of extended phenotypes in group selection.


Asunto(s)
Aptitud Genética , Selección Genética , Animales , Conducta Animal , Evolución Molecular , Modelos Genéticos , Fenotipo , Conducta Social
17.
Horm Metab Res ; 45(10): 765-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23918686

RESUMEN

The present study describes the preliminary results of the use of 99mTc-anti-TNF-α scintigraphy as a new diagnostic approach to evaluate patients presenting with Graves' ophthalmopathy (GO). Patients (n=25) presenting at different inflammatory stages of GO and 10 healthy volunteers underwent 99mTc-anti-TNF-α scintigraphy. Images were obtained 15 min after the intravenous injection of 370 MBq (10 mCi) 99mTc-anti-TNF-α. Planar images were obtained in a 256×256 matrix (each lasting 5 min) and single photon emission computed tomography (SPECT) scan lasting 13 min. Regions of interest (ROI) were drawn on the orbit and cerebral hemispheres. The uptake of 99m Tc-anti-TNF-α in these regions was compared and positive scintigraphy established when the ROI was >2.5. In addition, uptake for each positive exam was scored as either slight (2.6-5.1), moderate (5.2-7.6), or high (>7.6). In this pilot study, 69 orbits were evaluated (1 patient had only 1 eye), and 27 had a positive CAS (≥3/7). Scintigraphies were positive in 38 orbits. Comparing the results of the exams with CAS, a high sensitivity and negative predictive values were determined for scintigraphy (96.3% and 96.7%, respectively). However, the specificity and the positive predictive values were 71.4% and 68.4%, respectively, with an accuracy of 81.2%. The exclusion of examinations that were slightly positive from the analysis resulted in an improvement in test accuracy (95.5%). The preliminary results suggest that 99mTc-anti-TNF-α scintigraphy is a promising procedure for the evaluation of active orbital inflammation in GO.


Asunto(s)
Anticuerpos , Oftalmopatía de Graves/diagnóstico por imagen , Tecnecio , Tomografía Computarizada de Emisión de Fotón Único , Factor de Necrosis Tumoral alfa/inmunología , Adulto , Ojo/diagnóstico por imagen , Ojo/patología , Humanos , Inflamación/diagnóstico por imagen , Persona de Mediana Edad , Órbita/diagnóstico por imagen , Proyectos Piloto , Valor Predictivo de las Pruebas , Proyectos de Investigación , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
18.
Genet Mol Res ; 12(2): 2148-55, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23913392

RESUMEN

Landfarming biodegradation is a strategy used by the petrochemical industry to reduce pollutants in petroleum-contaminated soil. We constructed 2 metagenomic libraries from landfarming soil in order to determine the pathway used for mineralization of benzene and to examine protein expression of the bacteria in these soils. The DNA of landfarm soil, collected from Ilhéus, BA, Brazil, was extracted and a metagenomic library was constructed with the Copy Control(TM) Fosmid Library Production Kit, which clones 25-45-kb DNA fragments. The clones were selected for their ability to express enzymes capable of cleaving aromatic compounds. These clones were grown in Luria-Bertani broth plus L-arabinose, benzene, and chloramphenicol as induction substances; they were tested for activity in the catechol cleavage pathway, an intermediate step in benzene degradation. Nine clones were positive for ortho-cleavage and one was positive for meta-cleavage. Protein band patterns determined by SDS-polyacrylamide gel electrophoresis differed in bacteria grown on induced versus non-induced media (Luria-Bertani broth). We concluded that the DNA of landfarm soil is an important source of genes involved in mineralization of xenobiotic compounds, which are common in gasoline and oil spills. Metagenomic library allows identification of non-culturable microorganisms that have potential in the bioremediation of contaminated sites.


Asunto(s)
Bacterias/enzimología , Bacterias/genética , Biblioteca de Genes , Metagenómica/métodos , Microbiología del Suelo , Bacterias/metabolismo , Biodegradación Ambiental , Brasil , ADN Bacteriano/análisis , ADN Bacteriano/genética , Hidrocarburos Aromáticos/metabolismo , Petróleo/metabolismo , Contaminantes del Suelo/metabolismo , Xenobióticos/metabolismo
19.
J Phys Condens Matter ; 25(30): 306003, 2013 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-23822936

RESUMEN

In this paper we explore the entanglement in an orthogonal dimer-plaquette Ising-Heisenberg chain, assembled between plaquette edges, also known as orthogonal dimer plaquettes. The quantum entanglement properties involving an infinite chain structure are quite important, not only because the mathematical calculation is cumbersome but also because real materials are well represented by infinite chains. Using the local gauge symmetry of this model, we are able to map onto a simple spin-1 like Ising and spin-1/2 Heisenberg dimer model with single effective ion anisotropy. Thereafter this model can be solved using the decoration transformation and transfer matrix approach. First, we discuss the phase diagram at zero temperature of this model, where we find five ground states, one ferromagnetic, one antiferromagnetic, one triplet-triplet disordered and one triplet-singlet disordered phase, beside a dimer ferromagnetic-antiferromagnetic phase. In addition, we discuss the thermodynamic properties such as entropy, where we display the residual entropy. Furthermore, using the nearest site correlation function it is possible also to analyze the pairwise thermal entanglement for both orthogonal dimers. Additionally, we discuss the threshold temperature of the entangled region as a function of Hamiltonian parameters. We find a quite interesting thin reentrance threshold temperature for one of the dimers, and we also discuss the differences and similarities for both dimers.

20.
Rev. argent. reumatol ; 24(4): 8-14, 2013. ilus, tab
Artículo en Español | LILACS | ID: biblio-835773

RESUMEN

Introducción: BIOBADASAR (Registro Argentino de Eventos Adversos con Tratamientos Biológicos en Reumatología) comenzó en agosto de 2010. La importancia de este registro es mostrar datos locales que, probablemente, puedan diferir de otros registros. El objetivo es comunicar los resultados del tercer reporte de BIOBADASAR. Métodos: Todos los pacientes con enfermedades reumáticas que requirieron tratamiento con agentes biológicos y pacientes controles sin estos tratamientos fueron incluidos en la base de datos provenientes de 32 centros participando a lo largo de la Argentina. Tres áreas de datos son analizados: características de los pacientes, tratamientos y eventos adversos...


Introduction: BIOBADASAR (Argentine Registry of Adverse Events with Biological Treatments in Rheumatology) began in August 2010. The importance of this registry is to show local data that may probably differ from other registries. The objective is to communicate the results of the third BIOBADASAR report. Methods: All patients with rheumatic diseases who required treatment with biological agents and control patients without these treatments were included in the database from 32 participating centers throughout Argentina. Three areas of data are analyzed: patient characteristics, treatments and adverse events...


Asunto(s)
Tratamiento Biológico , Enfermedades Reumáticas , Reumatología
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