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Bladder cancer mortality trends and patterns in Córdoba, Argentina (1986-2006)

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Bladder cancer mortality trends and patterns in Córdoba, Argentina (1986-2006) Pou, Sonia Alejandra; Osella, Alberto Ruben; Diaz, Maria del Pilar Background Bladder cancer is common worldwide and the fourth most commonly diagnosed malignancy in men in Argentina. Objective To describe bladder cancer mortality trends in Córdoba (1986-2006), considering the effect of age, period, and cohort, and to estimate the effect of arsenic exposure on bladder cancer, and its interaction with sex, while controlling by smoking habits and space and time variation of the rates. Methods A joinpoint regression was performed to compute the estimated annual percentage changes (EAPC) of the age-standardized mortality rates (ASMR) in an adult population from Córdoba, Argentina. A Poisson model was fitted to estimate the effect of age, period, and cohort. The influence of gender, tobacco smoking (using lung cancer ASMR as surrogate), and arsenic in drinking water was examined using a hierarchical model. Results A favorable trend (1986-2006) in bladder cancer ASMR in both sexes was found: EAPC of -2.54 in men and -1.69 in women. There was a decreasing trend in relative risk (RR) for cohorts born in 1931 or after. The multilevel model showed an increasing risk for each increase in lung cancer ASMR unit (RR = 1.001) and a biological interaction between sex and arsenic exposure. RR was higher among men exposed to increasing As-exposure categories (RR male low exposure 3.14, RR male intermediate exposure 4.03, RR male high exposure 4.71 versus female low exposure). A non-random space- time distribution of the rates was observed. Conclusions There has been a decreasing trend in ASMR for bladder cancer in Córdoba. This study confirms that bladder cancer is associated with age, gender, smoking habit, and exposure to arsenic. Moreover, an effect measure modification between exposure to arsenic and sex was found.

Melatonin agonists for treatment of sleep and depressive disorders

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Melatonin agonists for treatment of sleep and depressive disorders Srinivasan, Venkataramanujan; Cardinali, Daniel Pedro; Pandi Perumal, Seithikurippu R.; Brown, Gregory M. Melatonin the hormone secreted by the pineal gland has been effective in improving sleep both in normal sleepers and insomniacs and has been used successfully in treating sleep and circadian rhythm sleep disorders. The lack of consistency in the reports published by the authors is attributed to the differential bioavailabilty and short half-life of melatonin. Sleep disturbances are also prominent features of depressive disorders. To overcome this problem, melatonergic agonists with sleep promoting properties have been introduced in clinical practice. Ramelteon, the MT1/ MT2 melatonergic agonist, has been used in a large number of clinical trials involving chronic insomniacs and has been found effective in improving the total sleep time and sleep efficiency of insomniacs and has not manifested serious adverse effects. The development of another MT1/MT2 melatonergic agonist agomelatine with antagonsim to 5-HT2c serotonin receptors has been found useful not only in treating sleep problems of patients but also as a first line antidepressant with earlier onset of actions in patients with major depressive disorder. An agonist for MT3 melatonin receptor has also been found effective in animal models of depression.

Melatonin-A pleiotropic, orchestrating regulator molecule

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Melatonin-A pleiotropic, orchestrating regulator molecule Hardeland, Rüdiger; Cardinali, Daniel Pedro; Srinivasan, Venkatramanujam; Spence, David Warren; Brown, Gregory M.; Pandi Perumal, Seithikurippu R. Melatonin, the neurohormone of the pineal gland, is also produced by various other tissues and cells. It acts via G protein-coupled receptors expressed in various areas of the central nervous system and in peripheral tissues. Parallel signaling mechanisms lead to cell-specific control and recruitment of downstream factors, including various kinases, transcription factors and ion channels. Additional actions via nuclear receptors and other binding sites are likely. By virtue of high receptor density in the circadian pacemaker, melatonin is involved in the phasing of circadian rhythms and sleep promotion. Additionally, it exerts effects on peripheral oscillators, including phase coupling of parallel cellular clocks based on alternate use of core oscillator proteins. Direct central and peripheral actions concern the up- or downregulation of various proteins, among which inducible and neuronal NO synthases seem to be of particular importance for antagonizing inflammation and excitotoxicity. The methoxyindole is also synthesized in several peripheral tissues, so that the total content of tissue melatonin exceeds by far the amounts in the circulation. Emerging fields in melatonin research concern receptor polymorphism in relation to various diseases, the control of sleep, the metabolic syndrome, weight control, diabetes type 2 and insulin resistance, and mitochondrial effects. Control of electron flux, prevention of bottlenecks in the respiratory chain and electron leakage contribute to the avoidance of damage by free radicals and seem to be important in neuroprotection, inflammatory diseases and, presumably, aging. Newly discovered influences on sirtuins and downstream factors indicate that melatonin has a role in mitochondrial biogenesis.

Fallas con actividad cuaternaria en el corredor tectónico Matagusanos - Maradona - Acequión entre los ríos de La Flecha y del Agua, provincia de San Juan

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Fallas con actividad cuaternaria en el corredor tectónico Matagusanos - Maradona - Acequión entre los ríos de La Flecha y del Agua, provincia de San Juan; Faults with Quaternary activity in the Matagusanos-Maradona-Acequión tectonic depression between the ríos de la La Flecha and del Agua, San Juan province Perucca, Laura Patricia A.; Onorato, Maria Romina En la depresión situada entre los ríos de La Flecha y del Agua, se encuentran evidencias de fallamiento cuaternario, entre dos sistemas estructurales con rumbo norte y vergencias opuestas, Precordillera Central con vergencia oriental y estilo de piel fina y Precordillera Oriental, con vergencia occidental y piel gruesa. Se reconocieron numerosas fallas con actividad cuaternaria a lo largo de toda la depresión: aquellas ubicadas en su porción oriental, en las proximidades del cerro La Chilca, con el mismo estilo estructural de Precordillera Oriental: fallas inversas inclinando al este con alto ángulo en la superficie. Por el contrario, las fallas localizadas en el piedemonte oriental del cordón de Las Osamentas tienen un estilo estructural consistente con Precordillera Central, inversas y con vergencia oriental. Este arreglo estructural de las fallas cuaternarias con vergencia opuesta se compara con aquellos descriptos en la depresión de Matagusanos, donde se identificó una zona triangular de tipo piel gruesa localizada cerca de su porción occidental y en el valle de Zonda, situado al norte del sector analizado.; Evidence of Quaternary faults between two structural systems with regional N-trending strike and opposite vergence occur at the depression located between La Flecha and del Agua rivers; the east-verging thin-skinned Central Precordillera and the west-verging, thick-skinned Eastern Precordillera. Several Quaternary faults have been recognized across the whole depression. Those located in the eastern sector near Cerro La Chilca, show the structural style of Precordillera Oriental: east-dipping reverse faults with a high angle on the surface. On the contrary, faults located at the eastern piedmont of Cordón de Las Osamentas have a structural style consistent with Precordillera Central, reverse faults and east vergence. This structural arrange of Quaternary faults with opposite vergence was compared with those described at Matagusanos depression, where a triangular zone of thick-skinned type is located close to the western sector of the depression and with the zonda valley, located in the northern sector of the study area.

High T/P evolution and metamorphic ages of the migmatitic basement of northern Sierras Pampeanas, Argentina: Characterization of a mid-crustal segment of the Famatinian belt

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High T/P evolution and metamorphic ages of the migmatitic basement of northern Sierras Pampeanas, Argentina: Characterization of a mid-crustal segment of the Famatinian belt Larrovere, Mariano Alexis; de Los Hoyos, Camilo Raul; Toselli, Alejandro Jose; Rossi, Juana Norma; Stipp Basei, Miguel Angelo; Belmar, Mauricio E. New petrologic, thermobarometric and U-Pb monazite geochronologic information allowed to resolve the metamorphic evolution of a high temperature mid-crustal segment of an ancient subduction-related orogen. The El Portezuelo Metamorphic-Igneous Complex, in the northern Sierras Pampeanas, is mainly composed of migmatites that evolved from amphibolite to granulite metamorphic facies, reaching thermal peak conditions of 670-820 °C and 4.5-5.3 kbar. The petrographic study combined with conventional and pseudosection thermobarometry led to deducing a short prograde metamorphic evolution within migmatite blocks. The garnet-absent migmatites represent amphibolite-facies rocks, whereas the cordierite-garnet-K-feldspar-sillimanite migmatites represent higher metamorphic grade rocks. U-Pb geochronology on monazite grains within leucosome record the time of migmatization between ≈477 and 470 Ma. Thus, the El Portezuelo Metamorphic-Igneous Complex is an example of exhumed Early Ordovician anatectic middle crust of the Famatinian mobile belt. Homogeneous exposure of similar paleo-depths throughout the Famatinian back-arc and isobaric cooling paths suggest slow exhumation and consequent longstanding crustal residence at high temperatures. High thermal gradients uniformly distributed in the Famatinian back-arc can be explained by shallow convection of a low-viscosity asthenosphere promoted by subducting-slab dehydration.

Pharmacokinetics of ceftazidime administered to lactating and non-lactating goats

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Pharmacokinetics of ceftazidime administered to lactating and non-lactating goats Rule, R.; Villagra, S.; Barrena Chiantelassa, Jorge Pablo; Lacchini, Raul Alfredo; Reynaldi, Francisco José The aim of this work was to determine the pharmacokinetics of intravenous (iv) and intramuscular (im) ceftazidime administered to lactating (LTG; n = 6) and non-lactating (NLTG; n=6) healthy Creole goats in 2 trials (T1 and T2). During T1 and T2, goats randomly received a single dose of im or iv ceftazidime (10 mg/kg). Serum concentration of iv ceftazidime in NLTG and LTG goats is best described by 2 and 3 compartment models, respectively. The pharmacokinetic parameters of iv and im ceftazidime administered to LTG and NLTG showed statistically significant differences (P<0.05) in the constants (λz, T1 vs T2 [iv] 0.5±0.1 vs 0.3±0.1 /h; T1 vs T2 [im] 0.5±0.2 vs 0.3±0.1 /h) and in the mean times (t1/2, T 1 vs T 2 [iv] 1.6±0.3 vs 2.3±0.6 h; T 1 vs T 2 [im] 1.6±0.7 vs 2.6±0.9 h) of elimination. The bioavailability of ceftazidime in LTG and NLTG was 113.0 ± 17.8 and 96.0 ± 18.0 %, respectively. Ceftazidime concentration in milk at 2 h was: iv = 1.9 ± 0.2 and im = 2.4 ± 0.5 μg/m ; the penetration in milk was iv = 18.3 ± 13.5 and im = 14.3 ± 10.6 %. Ninety-six hours after iv and im administration, residues of the drug were not found in milk. In conclusion, ceftazidime, when administered to goats, showed high concentration times in serum, good penetration into milk and a bioavailability that makes it suitable to be used by the im route.

Dealing with incompleteness: New advances for the use of fossils in phylogenetic analysis

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Dealing with incompleteness: New advances for the use of fossils in phylogenetic analysis Escapa, Ignacio Hernán; Pol, Diego The importance of fossils in understanding the evolutionary history of organisms was a controversial topic of debate during the first few decades in the history of phylogenetic systematics. During this time some authors suggested that extinct taxa could have only a minor role in phylogeny reconstruction (e.g., Patterson, 1981). For the most part, these types of bold statements were based on the fact that fossils are usually incomplete and, therefore, presumably not capable of overturning hypotheses based on the wealth of phylogenetic information that extant taxa provide. However, phylogenetic studies based only on extant organisms are certainly missing a large part of the diversity that arose during the evolutionary history of a taxonomic group and therefore use a highly biased sampling of the available information.

Recycled Concretes Made with Waste Ready-Mix Concrete as Coarse Aggregate

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Recycled Concretes Made with Waste Ready-Mix Concrete as Coarse Aggregate Zega, Claudio Javier; Di Maio, Angel Antonio Using waste materials for new products is a global trend undergoing rapid development. Recycling materials allows for a more efficient life cycle and contributes to environmental protection. In the construction field, this trend has gained importance because of the shortage of natural resources and because of environmental problems caused by storing building-demolition wastes. This situation has led to the search for new applications for these wastes, and their use as aggregates in concrete is an interesting alternative. In this paper, some characteristics of recycled coarse aggregates obtained by crushing waste ready-mix concrete, as well as the mechanical and durability properties of recycled concretes made by using 25, 50, and 75% of these aggregates, are presented. Recycled concretes show lower compressive strength than conventional concrete for the higher strength level, whereas the durability properties of the two are similar.

Husbandry of a pink fairy armadillo (Chlamyphorus truncatus): Case study of a cryptic and little known species in captivity

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Husbandry of a pink fairy armadillo (Chlamyphorus truncatus): Case study of a cryptic and little known species in captivity Superina, Mariella Pink fairy armadillos, Chlamyphorus truncatus, are poorly known fossorial mammals that are endemic to central Argentina. These smallest of all extant armadillos are rarely observed in the field and extremely difficult to maintain under captive conditions. This case study describes the husbandry of a male pink fairy armadillo that was maintained in an artificial environment for 8 months. A stable, undisturbed environment consisting of abundant compact sand and hiding places on the surface was the key to its successful maintenance. The artificial diet consisted of a semiliquid mixture of ground cat food, insectivore diet, mashed banana, vitamins, and minerals. Any slight modification to its environment or diet triggered a stress response.

Estimación de las frecuencias alélicas del gen BoLA-DRB3 en una población de ganado Holstein de La Pampa mediante secuenciación directa

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Estimación de las frecuencias alélicas del gen BoLA-DRB3 en una población de ganado Holstein de La Pampa mediante secuenciación directa; Gene frequencies of BoLA-DRB3 alleles estimated through sequence-based typing (PCR-SBT) in a Holstein population of La Pampa province Baltian, Laura Rosana; Ripoli, María Verónica; Takeshima, S. N.; Aida, Y.; Giovambattista, Guillermo El objetivo del presente estudio consistió en estimar las frecuencias alélicas del exón 2 del gen de Clase II del Sistema Principal de Histocompatibilidad BoLA-DRB3 en una población de ganado Holstein de la provincia de La Pampa. Los polimorfismos presentes en el exón 2 del gen BoLA-DRB3 se identificaron mediante la técnica de secuenciación directa (PCR-SBT). Los resultados obtenidos permitieron detectar un total de 21 alelos con un rango de frecuencia de 0,014 a 0,222. Esto resultó en una heterocigosidad esperada de 0,91. Estos resultados se compararon con los reportados para ganado Holstein de Japón, evidenciando que con la excepción del alelo BoLA-DRB3*1201, ambas poblaciones presentaron los mismo alelos mayoritarios (BoLA-DRB3*1101, *1501 y *0101). Este resultado sería consecuencia del alto nivel de homogeneidad exhibido por esta raza, debido al uso de la misma genética a nivel global.; The objective of this study was to estimate allele frequencies of the BoLA-DRB3 exon 2 in a Holstein population from La Pampa province. The exon 2 polymorphisms were genotyped by sequence-based typing method (PCR-SBT). In the studied herd, a total of 21 variants were detected, ranging from 0.014 to 0.222. This resulted in an expected heterozygocity of 0.91. Obtained data were compared with those reported for Japanese Holstein population, showing that with the exception of BoLA-DRB3*1201 allele, both populations shared the same major variants (BoLA-DRB3*1101, *1501 and *0101). This result could be consequence of the high level of homogeneity present in Holstein breed, due to the use of same genetic on the whole world.

Occurrence of Anopheles (Anopheles) neomaculipalpus Curry innorth-western Argentina

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Occurrence of Anopheles (Anopheles) neomaculipalpus Curry innorth-western Argentina Dantur Juri, Maria Julia; Stein, Marina; Mureb Sallum, María A. Malaria, which is considered as one of the most important tropical diseases, affects millons of people around the world. Its wide geographical distribution in Argentina in the 1940s is now confined only to the extreme north area of the country, where it is difficult to eradicate. Since 2000, official reports of malaria mentioned <300 cases, only 209 cases being reported in 2006.

Análisis de la campaña 2010 de poroto en Tucumán y resto del NOA

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Análisis de la campaña 2010 de poroto en Tucumán y resto del NOA Vizgarra, Oscar N.; Espeche, Maria Carolina; Luchina, Jeremias Nicolas; Ploper, Leonardo Daniel La producción de poroto (Phaseolus vulgaris L.) en la Argentina tiene lugar en las provincias del noroeste (NOA), especialmente Salta, Tucumán, Santiago del Estero, Catamarca y Jujuy. Los tipos de poroto, que más se producen son los de color negro y los blancos tipo alubia. Se estima que en 2010 la superficie sembrada en la provincia de Tucumán fue de 10.000 ha, correspondiendo el 80% de la superficie a poroto negro y el resto a blanco y rojo; mientras que en las zonas de influencia (oeste de Santiago del Estero, sur de Salta y sur de Catamarca) se sembraron alrededor de 40.000 ha. En el resto del noroeste argentino (NOA), norte de Salta y Jujuy, se sembraron 40.000 ha de poroto negro, 130.000 ha de blanco y 45.000 ha de otros colores (rojos, cranberrys, canelas, etc.). En el presente trabajo se consideran diversos aspectos de la campaña 2010 de poroto en el NOA. También se presentan resultados de cultivares promisorios de poroto en los ensayos que la Estación Experimental Agroindustrial ?Obispo Colombres? (EEAOC) conduce en diferentes localidades, para evaluar porotos de colores tradicionales (negros, blancos) y no tradicionales (cranberry, dark red kidney, light red kidney, canelas, entre otros) para la región. Asimismo, se comentan los resultados de evaluación de materiales con resistencia a la mancha angular, evaluados en las localidades de Pozo Hondo y Los Altos.

Comparison of plasma dipeptidyl peptidase IV activity in two caiman species: Caiman latirostris and Caiman yacare (Crocodylia, Alligatoridae)

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Comparison of plasma dipeptidyl peptidase IV activity in two caiman species: Caiman latirostris and Caiman yacare (Crocodylia, Alligatoridae) Siroski, Pablo Ariel; Merchant, Mark E.; Parachu Marco, Maria Virginia; Poletta, Gisela Laura; Ortega, Hugo Hector Dipeptidyl peptidase IV (DPPIV) is a well-characterized protease with broad substrate specificity, functionally-related to the activity of many bioactive peptides. It plays an important role as physiological regulator of a number of peptides that serve as biochemical messengers within the immune system. Plasma DPPIV activity was characterized with respect to temperature, kinetics and concentration dependence in two species of caiman, the broad-snouted caiman (Caiman latirostris) and the black yacare (Caiman yacare). DPPIV activity showed a significant positive correlation from titrations carried out in the presence of different plasma concentrations. DPPIV activity was lower in C. yacare than in C. latirostris at all temperatures tested. C. yacare DPPIV activity showed a significant increase only at higher temperatures whilst C. latirostris plasma demonstrated a strong positive correlation starting at the lowest temperature, probably due to an adaptation for the tolerance of lower temperatures. Exposure of C. latirostris and C. yacare plasma at different time points showed that plasma DPPIV activities were time-dependent, and that the titer-dependent curves were different for the two species. These results revealed that plasma DPPIV activities were different between these two crocodilian species, which could contribute to the differences in susceptibility to infection between them. © 2011 Koninklijke Brill NV, Leiden.

Differentiation of isomeric hydroxypyridine N-Oxides using metal complexation and electrospray ionization mass spectrometry

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Differentiation of isomeric hydroxypyridine N-Oxides using metal complexation and electrospray ionization mass spectrometry Butler, Matias; Arroyo Mañez, Pau; Cabrera, Gabriela Myriam Differentiation between two isomers of hydroxypyridine N-oxide according to the metal cation adducts generated by electrospray ionization (ESI) was investigated for different metal cations, namely Mg (II), Al (III), Ca (II), Sc (III), Fe (III), Co (II), Ni (II), Cu (II), Zn (II), Ga (III), besides the diatomic cation VO(IV). Protonated molecules of the isomeric hydroxypyridine N-oxides as well as the singly/doubly charged adducts formed from neutral or deprotonated ligands and a doubly/ triply charged cation were produced in the gas phase using ESI, recording mass spectra with different metal ions for each isomer. While complex formation was successful for 2- hydroxypyridine N-oxide with trivalent ions, in the case of 3-hydroxypyridine N-oxide, only peaks related to the protonated molecule were present. On the other hand, divalent cations formed specific species for each isomer, giving characteristic spectra in every case. Hence, differentiation was possible irrespective of the metal cation utilized. In addition, quantum chemical calculations at the B3LYP/6-31+G(d,p) level of theory were performed in order to gain insight into the different complexation of calcium(II) with the isomers of hydroxypyridine N-oxide. The relative stability in the gas phase of the neutral complexes of calcium made up of two ligands, as well as the singly charged and doubly charged complexes, was investigated. The results of these calculations improved the understanding of the differences observed in the mass spectra obtained for each isomer.

Thermoelastic dynamic stability of thin-walled beams with graded material properties

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Thermoelastic dynamic stability of thin-walled beams with graded material properties Piovan, Marcelo Tulio; Machado, Sebastián Pablo The dynamic stability of functionally graded thin-walled beams allowing for shear deformability is investigated in this article. The analysis is based on a model that has small strains and moderate rotations which are formulated through the adoption of a second-order non-linear displacement field. The beam is subjected to axial external dynamic loading. The model takes into account thermoelastic effects. The heat conduction equation is solved in order to characterize the temperature in the cross-sectional domain. Galerkin's and Bolotin's methods are employed with the scope to discretize the governing equations and to determine the regions of dynamic stability, respectively. Regions of stability are evaluated and expressed in non-dimensional form. The influence of the longitudinal vibration on the unstable regions is investigated. The numerical results show the importance of this effect when the forcing frequency approaches to the natural longitudinal frequency, obtaining substantially wider parametric stability regions. The effects of temperature gradients, shear flexibility and axial inertia, in beams with different cross-sections and different types of graded material are analyzed as well.

Myoclonus and angiokeratomas in adult galactosialidosis

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Myoclonus and angiokeratomas in adult galactosialidosis Abaroa, Luz; Garretto, Nelida S.; Arakaki, Tomoko; Kauffman, Marcelo Andres; González Morón, Dolores; Figueredo, Alex M.; Szlago, Marina; Verhagen Metman, Leo Galactosialidosis is an autosomal recessive lysosomal storage disorder characterized by a combined deficiency of b- galactosidase and a-neuraminidase, due to a defect of another lysosomal protein, cathepsin A. The latter, forms a complex with b-galactosidase and neuraminidase, and protects them against excessive proteolytic degradation. Three clinical phe- notypes had been described: a severe early infantile form; a milder late infantile type with minor mental deterioration; and a juvenile/adult form, mainly found in Japan, which is characterized by slowly progressive neurological symptoms, skeletal and eye abnormalities, dysmorphism, angiokerato- mas, and long survival.1 Herein, we report a case of galacto- sialidosis of the juvenile-adult form in a Peruvian girl with angiokeratoma corporis diffusum (ACD) and myoclonus. A 24-year-old woman presented a 5-year history of invol- untary movements. At age 19, she developed a progressive myoclonic disorder that started in the lower limbs and caused frequent falls. The myoclonus subsequently spreads to other body regions. Five years into the disease, she was almost wheelchair bound, and other activities such as eating and speaking were considerably affected. There were, how- ever, no seizures or cognitive decline.Physical examination revealed densely peppered red mac- ules ranging from 1 to 3 mm on palms, elbows, knees, oral mucosa, lips, and on thighs and loins in a bath- ing suit distribution. Biochemical analysis showed elevated urinary sialyloligosaccharides char- 1 acteristic for galactosialidosis.

Infrared study of trifluoroacetic acid unpurified synthetic peptides in aqueous solution: Trifluoroacetic acid removal and band assignment

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Infrared study of trifluoroacetic acid unpurified synthetic peptides in aqueous solution: Trifluoroacetic acid removal and band assignment Valenti, Laura Elisa; Burgos Paci, Maximiliano Alberto; de Pauli, Carlos Primo; Giacomelli, Carla Eugenia Synthetic peptide or protein samples are mostly unpurified with trifluoroacetic acid (TFA) used during the synthesis procedure, which strongly interferes with structure determination by infrared (IR) spectroscopy. The aim of this work was to propose a simple strategy to remove TFA contribution from attenuated total reflection (ATR)-IR spectra of the hexahistidine peptide (His6) in aqueous solution to study the conformation of this synthetic peptide without previous purification. Such a strategy is based on the subtraction mode widely employed to remove water contribution, and it is tested with TFA unpurified histidine as a model system. The subtraction is based on eliminating the strong TFA bands at 1147 and 1200 cm-1 by applying a scaling factor (as in buffer correction). The proposed modes represent excellent strategies that do not modify spectral features, and they provide reliable routines to obtain the synthetic peptide spectrum without TFA contribution. The conformational information from the corrected spectra at different pH values is deduced from semiempirical calculated IR spectra of different His6 conformers. The spectral features and the band positions of the corrected spectrum suggest that the peptide molecules mainly adopt an intermolecular β-sheet structure.

Label-free biosensing based on multilayer fluorescent nanocomposites and a cationic polymeric transducer

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Label-free biosensing based on multilayer fluorescent nanocomposites and a cationic polymeric transducer Brouard, Danny; Viger, Mathieu L.; Bracamonte, Angel Guillermo; Boudreau, Denis This study describes the preparation and characterization of a DNA sensing architecture combining the molecular recognition capabilities of a cationic conjugated polymer transducer with highly fluorescent core-shell nanoparticles (NPs). The very structure of the probe-labeled NPs and the polymer-induced formation of NP aggregates maximize the proximity between the polymer donor and acceptor NPs that is required for optimal resonant energy transfer. Each hybridization event is signaled by a potentially large number of excited reporters following the efficient plasmon-enhanced energy transfer between target-activated polymer transducer and fluorophores located in the self-assembled core-shell aggregates, resulting in direct molecular detection of target nucleic acids at femtomolar concentrations. © 2011 American Chemical Society.

Perspective - from describing to understanding environment-physiology relations: 50th birthday of a branch in ecophysiology

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Perspective - from describing to understanding environment-physiology relations: 50th birthday of a branch in ecophysiology Schwarzbaum, Pablo Julio; Krumschnabel, Gerhard Animals generally show various adaptation features that render them fit for survival in their specific environment or, turned the other way round, specific environments can only be inhabited by animals that have developed corresponding adaptations. While this seems obvious nowadays to every biologist, 50 years ago this concept still needed to be validated for each specific case. In a brief historical perspective we highlight an outstanding example of an article where such environment–physiology relations have been examined in detail and where in fact the foundations of a new branch in ecophysiology have been established, the Ecophysiology of the Marine Meiofauna.

Effects of PPAR activation in the placenta and the fetus: implications in maternal diabetes

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Effects of PPAR activation in the placenta and the fetus: implications in maternal diabetes Jawerbaum, Alicia Sandra; Capobianco, Evangelina Lorena Peroxisome proliferator-activated receptors (PPARα, PPARδ and PPARγ) are ligand-activated transcription factors that regulate metabolic, anti-inflammatory and developmental processes. The maternal and fetal metabolic impairments, the intrauterine pro-inflammatory environment and the developmental defects induced by maternal diabetes make PPARs an interesting focus of investigation. Therefore, research has been conducted in experimental models of diabetes throughout gestation. During embryo organogenesis, impaired PPARδ signaling pathways are related to the induction of congenital malformations. In fetuses from diabetic rats, both lipid metabolism and several pro-inflammatory markers are regulated by the activation of PPAR isotypes. In the placenta from diabetic animals, activation of different PPAR isotypes regulates lipid metabolism and anti-inflammatory pathways, whereas in term placentas from diabetic patients PPARγ reduces the production of nitric oxide. Decreased PPARγ and PPARα protein expression are found in term placentas of diabetic animals and diabetic patients. In addition, a deficiency in polyunsaturated fatty acids (PUFAs) and impaired formation of arachidonic acid derivatives that activate PPARs is found in several diabetic intrauterine tissues. PPARs can be activated by both natural and pharmacological activators. Intrauterine activation of PPARs can be achieved by the administration of maternal diets enriched in PUFAs. This review summarizes recent advances highlighting the possible beneficial role of PPAR activation on embryonic and feto-placental development in maternal diabetes.

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