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Although normal aging has been related to several cognitive difficulties, other processes have been studied less, such as spatial memory. Our aim was to compare egocentric and allocentric memory in an elderly population using ecological tasks. Twenty-eight cognitively unimpaired participants performed Egocentric and Allocentric Spatial Memory Tasks, as well as Spatial Span from CANTAB, Benton's Judge of Line Orientation test (JoLO), and Montreal Cognitive Assessment test (MoCA). The results revealed that younger participants showed better performance than older participants on both the Egocentric and Allocentric Spatial Memory Tasks, although only the Egocentric test was able to discriminate between younger, middle, and older elderly participants. Learning effect was found in Allocentric Spatial Memory Task in younger and older groups, but not in the middle group. Allocentric and egocentric performance was not related to other visuospatial neuropsychological scores and gender did not influence performance in any task. Egocentric and Allocentric Spatial Memory Tasks may be useful tools in early screening for cognitive decline, as they are able to detect age differences in the cognitive unimpaired elderly population.

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Avian eggshell membranes are good candidates as a matrix for immobilization procedures. Chicken eggshell, a waste material available from the poultry industry as a byproduct, is a very safe and cheap raw material. While pieces of eggshell membrane, or even particles from whole eggshell, have been previously used for these purposes, we report here the use of eggshell membrane powder for E. coli ß-galactosidase immobilization with glutaraldehyde as cross-linker. A kinetic characterization is provided for eggshell membrane powder-bound enzyme compared to free enzyme. Results show a remarkable similarity between bound and free enzyme and also that the immobilized enzyme is stable and can be reused several times. Moreover, bound enzyme is able to produce glucose from skim milk serum.

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Although normal aging has been related to several cognitive difficulties, other processes have been studied less, such as spatial memory. Our aim was to compare egocentric and allocentric memory in an elderly population using ecological tasks. Twenty-eight cognitively unimpaired participants performed Egocentric and Allocentric Spatial Memory Tasks, as well as Spatial Span from CANTAB, Benton's Judge of Line Orientation test (JoLO), and Montreal Cognitive Assessment test (MoCA). The results revealed that younger participants showed better performance than older participants on both the Egocentric and Allocentric Spatial Memory Tasks, although only the Egocentric test was able to discriminate between younger, middle, and older elderly participants. Learning effect was found in Allocentric Spatial Memory Task in younger and older groups, but not in the middle group. Allocentric and egocentric performance was not related to other visuospatial neuropsychological scores and gender did not influence performance in any task. Egocentric and Allocentric Spatial Memory Tasks may be useful tools in early screening for cognitive decline, as they are able to detect age differences in the cognitive unimpaired elderly population.

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This study aims at developing a method for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in rice grain samples by combining the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and determination by gas chromatography-mass spectrometry (GC-EI-MS). Quantification limits ranging from 1 to 5µgkg(-1) were obtained. Recoveries ranged from 70% to 106% for most of the 16 PAHs under analysis. The optimised methodology was applied to assess safety concerning the content of PAHs in white and parboiled rice samples, dried by gas and wood burning. Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the samples, naphthalene and phenanthrene were detected in all of them. Since cereals have been shown to be an important source of PAHs in the diet, methods that perform the evaluation of the quality of this food group become relevant.

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The use of extracellular matrix (ECM) molecules from tissues is an interesting way to induce specific responses of cells grown onto composite scaffolds to promote adhesion, proliferation and differentiation. There have been several studies on the effects on cell proliferation and differentiation of osteoprogenitor cells cultured onto composites, either adding some ECM molecules or grown in the presence of growth factors. Other studies involve the use of osteoblasts cultured on a three-dimensional (3D) matrix, enriched with ECM molecules produced by the same cells grown previously inside the composite. Here, the effect of enrichment of a novel multilayered chitosan-hydroxyapatite composite with ECM molecules produced by osteoblasts, or the addition of 25 or 50 µg/ml fibronectin to the composite, on proliferation and differentiation of osteoblasts cultured on these composites was studied. The results showed an increase in the number of osteoblasts from day 1 of culture, which was higher in the group grown onto composites enriched with the highest concentration of fibronectin or with ECM molecules produced naturally by osteoblasts cultured previously on them, when compared with the control group. However, this increment tended to decline in all groups after day 7 of culture, the day when they reached the highest peak of proliferation. Differentiation expressed as alkaline phosphatase activity followed the proliferation pattern of the cells cultivated on the scaffolds. The results demonstrate the potential offered by these enriched 3D multilayered composites for improving their ability as bone grafting material.

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The efficiency of chicken eggshell membranes combined with a minimally invasive small osteotomy procedure of the ulna to accomplish an efficient release of the radius so that it can continue to grow in an unstressed manner was tested in rabbits. Eggshell membranes were extracted from chicken eggs, rinsed, dried and sterilized with ethylene oxide for 24 h. For reactivity testing, four separate subcutaneous pockets were created in 10 rats in the paravertebral region by blunt dissection and eggshell membranes were implanted in two of them. After 1-16 weeks, the implants were retrieved with the surrounding soft tissues and submitted to histological examination. Subsequently, 10 rabbits were anaesthetized and a complete 0.5 mm wide osteotomy was performed in both the right and the left distal ulna. A piece of eggshell membranes was interposed in the osteotomy site of one ulna. The opposite osteotomized ulna was left as a negative control. The rabbits were injected with oxytetracycline at the time of surgery and this was repeated every 7 days for labelling new bone formation. After 1-16 weeks, ulnar osteotomized regions were histologically examined. After histological, fluorescence microscopy and radiological evaluation, we demonstrate here for the first time that eggshell membranes as interpositional material in rabbit osteotomized ulnar experiments acted as an active barrier against bone bridging. The degradation of the eggshell membrane, due to host reaction, appeared sufficiently late to cause the desirable delay of bone healing that is compatible with the time needed for a corrective response.

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The serious neuropsychological repercussions of hepatic encephalopathy have led to the creation of several experimental models in order to better understand the pathogenesis of the disease. In the present investigation, two possible causes of hepatic encephalopathy, cholestasis and portal hypertension, were chosen to study the behavioral impairments caused by the disease using an object recognition task. This working memory test is based on a paradigm of spontaneous delayed non-matching to sample and was performed 60 days after surgery. Male Wistar rats (225-250 g) were divided into three groups: two experimental groups, microsurgical cholestasis (N = 20) and extrahepatic portal hypertension (N = 20), and a control group (N = 20). A mild alteration of the recognition memory occurred in rats with cholestasis compared to control rats and portal hypertensive rats. The latter group showed the poorest performance on the basis of the behavioral indexes tested. In particular, only the control group spent significantly more time exploring novel objects compared to familiar ones (P < 0.001). In addition, the portal hypertension group spent the shortest time exploring both the novel and familiar objects (P < 0.001). These results suggest that the existence of portosystemic collateral circulation per se may be responsible for subclinical encephalopathy.

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The serious neuropsychological repercussions of hepatic encephalopathy have led to the creation of several experimental models in order to better understand the pathogenesis of the disease. In the present investigation, two possible causes of hepatic encephalopathy, cholestasis and portal hypertension, were chosen to study the behavioral impairments caused by the disease using an object recognition task. This working memory test is based on a paradigm of spontaneous delayed non-matching to sample and was performed 60 days after surgery. Male Wistar rats (225-250 g) were divided into three groups: two experimental groups, microsurgical cholestasis (N = 20) and extrahepatic portal hypertension (N = 20), and a control group (N = 20). A mild alteration of the recognition memory occurred in rats with cholestasis compared to control rats and portal hypertensive rats. The latter group showed the poorest performance on the basis of the behavioral indexes tested. In particular, only the control group spent significantly more time exploring novel objects compared to familiar ones (P < 0.001). In addition, the portal hypertension group spent the shortest time exploring both the novel and familiar objects (P < 0.001). These results suggest that the existence of portosystemic collateral circulation per se may be responsible for subclinical encephalopathy.

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The avian eggshell is an acellular bioceramic containing organic and inorganic phases that are sequentially assembled during the time the egg moves along the oviduct. As it has been demonstrated in other mineralized tissues, mineralization of the eggshell is regulated by extracellular matrix proteins especially the anionic side chains of proteoglycans. Among them, osteopontin has been found in the avian eggshell and oviduct. However, its precise localization in the eggshell or in different oviduct regions during eggshell formation, nor its function have been established. By using anti-osteopontin antibody (OPN 1), we studied its immunolocalization in the isthmus, red isthmus and shell gland of the oviduct, and in the eggshell during formation. In the eggshell, osteopontin was localized in the core of the non-mineralized shell membrane fibers, in the base of the mammillae and in the outermost part of the palisade. In the oviduct, OPN 1 was localized in the ciliated epithelial but not in the tubular gland cells of the isthmus, in the ciliated epithelial cells of the red isthmus, and in the non-ciliated epithelial cells of the shell gland. The occurrence of osteopontin in each of the oviduct regions, coincided with the concomitant presence of the egg in such region. Considering the reported inhibitory function of osteopontin in other mineralized systems, together with its main occurrence in the non-mineralized parts of the eggshell and at the outermost part of the shell, suggests that this molecule could be part of the mechanism regulating the eggshell calcification.

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The chicken eggshell is a composite bioceramic containing organic and inorganic phases. The organic phase contains, among other constituents, type X collagen and proteoglycans (mammillan, a keratan sulfate proteoglycan, and ovoglycan, a dermatan sulfate proteoglycan), whose localization depends on a topographically defined and temporally regulated deposition. Although the distribution of these macromolecules in the eggshell has been well established, little is known about their precise localization within eggshell substructures and oviduct cells or their pattern of production and function during eggshell formation. By using immunofluorescent and immuno-ultrastructural analyses, we examined the distribution of these macromolecules in oviduct cells at different post-oviposition times. To understand the role of proteoglycan sulfation on eggshell formation, we studied the effects of inhibition of proteoglycan sulfation by treatment with sodium chlorate. We showed that these macromolecules are produced by particular oviduct cell populations and at precise post-oviposition times. Based on the precise ultrastructural localization of these macromolecules in eggshell substructures, the timing of the secretion of these macromolecules by oviduct cells and the effects on eggshell formation caused by the inhibition of proteoglycan sulfation, the putative role of mammillan is in the nucleation of the first calcite crystals, while that of ovoglycan is to regulate the growth and orientation of the later forming crystals of the chicken eggshell.

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1. Eggshells are bioceramic-biopolymer composites made by a cell-mediated deposition of an extracellular matrix which drives the organisation of the inorganic phase. Ultrastructurally, eggshells are composed of shell membranes, mammillary knobs, palisade, and cuticle. Shell membranes are two nets of type X collagen-containing fibrils. On to these membranes, the mammillary knobs, that is, the crystal nucleation sites, are deposited. Type X collagen is highly cross-linked and insoluble. 2. In order to evaluate the role of type X collagen cross-linking on eggshell formation, hens were injected with different doses of beta-aminoproprionitrile, which specifically interferes with cross-link formation. 3. Changes in egg size and shape were observed. Scanning electron micrographs analysis of these eggs demonstrated marked changes in crystal growth and shell membrane structure and arrangement. A dot-blot analysis, using a monoclonal antibody against chicken type X collagen, shows a dose-dependent increase in shell membrane collagen extractability. 4. It is concluded that the formation of beta-aminoproprionitrile-sensitive cross-links among the type X collagen molecules of the shell membranes play an essential role in normal eggshell formation.

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The avian eggshell is a composite bioceramic which is formed by a controlled interaction of an organic and an inorganic phase. The organic phase contains, among other constituents, type X collagen and proteoglycans, mainly keratan and dermatan sulfate. Understanding the principles governing the synthesis and temporo-spatial distribution of such macromolecules, and their influence on the organization of the crystalline phase, is an essential aspect of establishing the biological basis of the quality of eggshell, both as an embryonic chamber and as a natural food package. In the present study, we have examined the process of eggshell formation by immunohistochemistry, scanning electron microscopy and energy dispersive X-ray microanalysis. Precise sites and timing of secretion were established for the deposition of particular macromolecules. Type X collagen is detected at the very first moment of shell membrane formation. The appearance of keratan sulfate coincides with the appearance of mammillae, while dermatan sulfate is deposited later, coincident with shell matrix deposition. We propose that keratan sulfate, due to its precise localization, temporal appearance and calcium-binding affinity, relates to the maintenance of calcium reserve bodies, the primary source of calcium for the embryo. On the other hand, dermatan sulfate may control crystal growth, resulting in a preferential orientation of calcite crystals within the palisade layer.

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Type X collagen is a transient and developmentally regulated collagen that has been postulated to be involved in controlling the later stages of endochondral bone formation. However, the role of this collagen in these events is not yet known. In order to understand the function of type X collagen, if any, in the process of biomineralization, the properties of type X collagen in eggshell membranes were further investigated. Specifically, calvaria-derived osteogenic cells were tested for their ability to mineralize eggshell membranes in vitro. Immunohistochemistry with specific monoclonal antibodies was used to correlate the presence or absence of type X collagen or its propeptide domains with the ability of shell membranes to be mineralized. The extent of mineralization was assessed by Von Kossa staining, scanning electron microscopy and energy-dispersive spectroscopy. The results indicate that the non-helical domains of type X collagen must be removed to facilitate the cell-mediated mineralization of eggshell membranes. In this tissue, intact type X collagen does not appear to stimulate or support cell-mediated mineralization. We postulate that the non-helical domains of type X collagen function in vivo to inhibit mineralization and thereby establish boundaries which are protected from mineral deposition.

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We studied 100 cases of prostatic disease with transrectal ultrasound; all were confirmed by histopathology. 83 cases were diagnosed as benign hyperplasia, 76 were confirmed 7 were cancer. Sensitivity 89.4%. 17 cases were diagnosed as cancer, biopsy confirmed 8, the other 9 were hyperplasia (sensitivity 53.3%). The more reliable ultrasonographic signs of cancer are the interruption on the continuity of the prostatic capsule, the extrinsic compression of the bladder and/or the seminal glands. The echogenicity of the prostatic tissue can have variations, it can be iso-, hypo- or hyperechoic in cancer and also in benign hyperplasia. We conclude, as in other reports, that transrectal ultrasound can demonstrate abnormal prostatic tissue, yet there is not enough sensitivity. Therefore biopsy is necessary and it can be performed by means of this procedure.

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La inyección de agentes neurolíticos es un tratamiento sintomático indicado principalmente en dolores de origen neoplásico en fase avanzada de la enfermedad y cuya eficacia es casi siempre temporal. El neurolítico ideal, capaz de producir un bloqueo permanente y prolongado sin destrucción de fibras nerviosas, no existe y todos los neurolíticos actualmente en uso presentan características individuales que limitan su empleo clínico. El alcohol, a pesar de sus inconvenientes, es el agente más eficaz para conseguir un bloqueo sensorial prolongado. Su utilización más frecuente es en la neuralgia del trigémino y por vía intradural en dolores neoplásicos. Para minimizar sus complicaciones no debe inyectarse más de 1 ml, muy lentamente, observando estrictamente los requisitos posturales durante la inyección y la primera hora después. El fenol se utiliza en solución acuosa pero sobre todo se utiliza como vehículo la glicerina a concentraciones del 5 al 10%. A diferencia del alcohol el bloqueo que produce es más selectivo y su densidad es superior a la del líquido cefalorraquídeo. Su eficacia máxima se observa en dolores neoplásicos de abdomen bajo y pelvis. Las sales de amonio son eficaces a concentraciones superiores al 6%. El nitrato de plata provoca una intensa reacción meníngea que limita su uso al fracaso del fenol. El clorocresol es más eficaz que el fenol, pero sus efectos son más tardíos. El éter intradural es efectivo, pero su hipobaricidad lo hace difícil de manejar. Las soluciones salinas hiperosmolares, o a bajas temperaturas, y el agua destilada también a bajas temperaturas han demostrado su utilidad. El último neurolítico, el glicerol, ha dado muy buenos resultados en la neuralgia del trigémino. El riesgo de producir lesiones neurológicas permanentes no justifica la utilización de neurolíticos en dolores no neoplásicos ni por personal no especializado

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La inyección de agentes neurolíticos es un tratamiento sintomático indicado principalmente en dolores de origen neoplásico en fase avanzada de la enfermedad y cuya eficacia es casi siempre temporal. El neurolítico ideal, capaz de producir un bloqueo permanente y prolongado sin destrucción de fibras nerviosas, no existe y todos los neurolíticos actualmente en uso presentan características individuales que limitan su empleo clínico. El alcohol, a pesar de sus inconvenientes, es el agente más eficaz para conseguir un bloqueo sensorial prolongado. Su utilización más frecuente es en la neuralgia del trigémino y por vía intradural en dolores neoplásicos. Para minimizar sus complicaciones no debe inyectarse más de 1 ml, muy lentamente, observando estrictamente los requisitos posturales durante la inyección y la primera hora después. El fenol se utiliza en solución acuosa pero sobre todo se utiliza como vehículo la glicerina a concentraciones del 5 al 10%. A diferencia del alcohol el bloqueo que produce es más selectivo y su densidad es superior a la del líquido cefalorraquídeo. Su eficacia máxima se observa en dolores neoplásicos de abdomen bajo y pelvis. Las sales de amonio son eficaces a concentraciones superiores al 6%. El nitrato de plata provoca una intensa reacción meníngea que limita su uso al fracaso del fenol. El clorocresol es más eficaz que el fenol, pero sus efectos son más tardíos. El éter intradural es efectivo, pero su hipobaricidad lo hace difícil de manejar. Las soluciones salinas hiperosmolares, o a bajas temperaturas, y el agua destilada también a bajas temperaturas han demostrado su utilidad. El último neurolítico, el glicerol, ha dado muy buenos resultados en la neuralgia del trigémino. El riesgo de producir lesiones neurológicas permanentes no justifica la utilización de neurolíticos en dolores no neoplásicos ni por personal no especializado (AU)

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