960 resultados para Colored microspheres
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Objective: The present study was performed to investigate the influence of different routes of perfusion on the distribution of the preservation solutions in the lung parenchyma and upper airways. Methods: Pigs were divided into four groups: control (n = 6), pulmonary artery (PA) (n = 6), simultaneous PA + bronchial artery (BA) (n = 8), and retrograde delivery (n = 6). After preparation and cannulation, cardioplegia solution and Euro- Collins solution (ECS) for lung preservation were given simultaneously. After removal of the heart, the double lung bloc was harvested. Following parameters were assessed: total and regional perfusion (dye-labeled microspheres), tissue water content, PA, aorta, left atrial and left ventricular pressures, cardiac output and lung temperature. Results: Our data show that flow of the ECS in lung parenchyma did not reach control values (9.4 ± 1.0 ml/min per g lung wet weight) regardless of the route of delivery (PA 6.3 ± 1.5, PA + BA 4.8 ± 0.9, retrograde 2.7 ± 0.9 ml/min per g lung wet weight). However, flow in the proximal and distal trachea were significantly increased by PA + BA delivery (0.970 ± 0.4, respectively, 0.380 ± 0.2 ml/min per g) in comparison with PA (0.023 ± 0.007, respectively, 0.024 ± 0.070 ml/min per g), retrograde (0.009 ± 0.003, respectively, 0.021 ± 0.006 ml/min per g) and control experiments (0.125 ± 0.0018, respectively, 0.105 ± 0.012 ml/g per min). Similarly the highest flow rates in the right main bronchus were achieved by PA + BA delivery (1.04 ± 0.4 ml/min per g) in comparison with 0.11 ± 0.03 in control, 0.033 ± 0.008 in PA, and 0.019 ± 0.005 ml/min per g in retrograde group. Flows in the left main bronchus were 0.09 ± 0.02 ml/min per g in control, 0.045 ± 0.012 ml/min per g in PA, and 0.027 ± 0.006 ml/min per g in retrograde group. The flow rates were significantly (P = 0.001) increased by PA + BA delivery of the storage solution (0.97 ± 0.3 ml/min per g). Conclusions: Our data show that the distribution of ECS for lung preservation is significantly improved in airway tissues (trachea and bronchi) if a simultaneous PA + BA delivery is used.
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Chronic hypertrophic pododermatitis cases in six horses of different breeds, aging 14 months to 19 years are described. The lesion begun with a infiltrative tissue in the frog and sole regions of the hoof, characterized by a fast and disorganized growth, with a papillary aspect, white colored in the roots and dark on the extremity, with a necrotic secretion and an extremely fetid odor. Microscopically, an exuberant epidermic proliferative tissue was observed, intermingled with little connective tissue. The horses were divided into two treatment groups. In the first group, including three young mares and a foal, showing lesions in only one limb, a surgical resection of the invasive mass was performed, followed by cauterization of the remaining edges and subsequent daily local application of antiseptic substances. In three of these horses, recurrence of the initial lesion occurred, with fast growth of hyperplasic tissue, affecting almost all the frog and half of the sole. Two horses developed contraction deformities of the hoof. In the second group, one male and one female, each with lesions in two limbs, after surgical debridement of the tissue, the animals received daily applications of picric acid 5%, associated to local use of oxitetracyclin. Although one of these cases required a second surgical intervention for removal of the mass, the horses showed after a period of two to three months total absence of the infiltrative tissue. The use of local picric acid 5% and oxitetracyclin associated to previous surgical debridement showed to be more efficient than the use of antiseptic substances in the treatment of chronic hypertrophic pododermatitis.
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A pair of Planalto Woodcreepers (Dendrocolaptes platyrostris) fed young in a nest cavity 6 m up in a wooded botanic garden of an old eucalyptus grove near São Paulo, Brazil, during October 1982. The pair often visited together at first, one (likely male) raising its head feathers as noted in other species of the genus. Feedings were less frequent at midday. Songs of the southeastern moist forest D. p. platyrostris were strikingly different from inland dry forest D. p. intermedius, despite intermediate specimens where the two rather distinctly colored forms come together. There are several poorly studied forms in interior dry forests, which need much more conservation effort.
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The reproducibility of measurements of alveolar bone loss on radiographs may be a problem on epidemiologic studies, as they are based on comparisons of the diagnosis of various examiners. The aim of the present research paper was to assess the inter- and intra-examiner reproducibility of measurements of the interproximal alveolar bone loss on non-manipulated digital radiographs and after the application of image filters. Five Oral Radiologists measured the distance between the cementoenamel junction (CEJ) to the alveolar crest or to the deepest point of the bony defect on 12 interproximal digital radiographs of molars and bicuspids of a dry human skull. The digital manipulation and the linear measurements were obtained with the Trophy Windows software (Throphy®). For each image, six different versions were created: 1) non-manipulated; 2) bright-contrast adjustment; 3) negative; 4) negative with brightness-contrast adjustment; 5) pseudo-colored; 6) pseudo-colored with brightness-contrast adjustment. In order to prevent interpretation bias because of the repetition of measurements, the examiners measured the radiographs in a random sequence. The two-way ANOVA test at 5% level of significance to compare the means of readings of the same operator with each filter indicated p<0.05 for the majority of operators, while the comparison between the mean values of operators using the same filter indicated p>0.05 for all filters. Based on the results, we concluded that linear measurements of interproximal alveolar bone loss on digital radiographs are highly reproducible among examiners. Nevertheless, the application of image filters significantly influenced the degree of intra-examiner reproducibility. Some filters even reduced the reproducibility of intra-examiner readings.
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Rhythmite samples from Varvite Quarry and Park of Itu (SP), and well cores from Rafard (SP), were analyzed by optical microscopy to describe the petrographic characteristics of their light-colored (siltstone) and dark-colored (shale) laminae. The light-colored ones are essentially siltstones, commonly with traces of sands; the mineralogical composition is mainly quartz, with traces of feldspar and scarce mica; quartz or calcite cementation occurs in variable intensity, the first one being more intense in the Itu rhythmites; parallel laminations, internally normal graded or massive are the most common sedimentary structures in these rocks; bioturbations and dropstones are commonly observed in Itu rhythmites; contacts between siltstone laminae, and siltstone beds and shale laminae are commonly non-erosive and sharp. Considering this study and the macroscopic description of these rhythmites it was possible to clarify many questions about their composition, as the grain-size of the light-colored beds composed by silt with subordinate dropped sand, and the inappropriate use of the term varvite to the most of the Itu rhythmites. It was also important to reinforce their proglacial lacustrine origin, with random freezing of lacustrine surface water, and only sporadic ice-contact.
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Purpose: To elaborate an experimental model of pulmonary carcinogenesis in Wistar rats. Methods: Male Rattus norvegicus albinus, Wistar lineage was carried through an intra-pulmonary instillation of the Benzo[a]pyrene (B[a]P) dilution in alcohol 70%, a polycyclic aromatic hydrocarbon widely known by its power of tumoral induction. Three experimental groups had been formed with 08 animals each: Control Group (Alcohol 70%); B[a]P Group 10 mg/kg; e B[a]P Group 20mg/ kg, submitted to euthanasia 08, 10, 12 and 14 weeks after the experimental procedure. The pulmonary sections had been colored by hematoxilin-eosin (HE) and submitted to the morphometrical analysis to describe the tissue alterations. Results: The presence of diffuse inflammatory alterations was observed in all groups, however, at the analysis of the pulmonary tissue of the experimental groups, it had been observed hyperplasic alterations (BALT hyperplasia), and in one of the animals of the experimental group 20mg/kg (12 weeks), it was noticed the presence of cellular epithelial tracheal pleomorphism, suggesting the adenocarcinoma formation in situ. Conclusion: The main secondary alterations to the intra-pulmonary instillation of B[a]P in Wistar rats were: cellular proliferation, inflammatory alterations of several degrees and nodular lymphoid hyperplasias. The association of an activator agent of the pulmonary metabolic reply is necessary to establish the ideal reply-dose to the development of the lung cancer.
Study of chromosomal and nucleolar aspects in testes of Nysius californicus (Heteroptera: Lygaeidae)
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In Nysius californicus (family Lygaeidae, subfamily Orsillinae), a pest commonly known as the seed bug, the chromosome complement is 2n = 16 (12A + 2m + XY), testes are formed by seven seminiferous tubules covered by an orange-colored membrane, and spermatogenesis is cystic. At prophase, sex chromosomes are heteropycnotic and autosomes usually show a chiasma. At metaphase, sex chromosomes along with microchromosomes may be seen located at the center of a ring formed by the remaining autosomes. A characteristic specific of N. californicus was the presence of nucleolar material observed from the cystic cell to the completely differentiated spermatozoon. Variations in size, shape and location of the nucleolar material occur during this process, denoting a variable degree of activity in the different stages. ©FUNPEC-RP.
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A simple analytical method for quantification of atenolol in pharmaceutical formulations by diffuse reflectance spectroscopy is described. The method is based on the reaction, on the filter paper surface, between the drug and p-chloranil producing a colored compound. The best reaction conditions were obtained with 20 μL of atenolol solution and 20 μL of p-chloranil. All reflectance measurements were carried out at 550 nm and the linear range was from 1.13×10-2 to 7.88×10-2 mol L-1 (r = 0.9992). The limit of detection was 2.80 × 10-3 mol L-1. The proposed method was successfully applied to analysis of different commercial brands of pharmaceutical formulations and the results obtained by the proposed method were in good agreement with those obtained using the British Pharmacopoeia method.
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A target tracking algorithm able to identify the position and to pursuit moving targets in video digital sequences is proposed in this paper. The proposed approach aims to track moving targets inside the vision field of a digital camera. The position and trajectory of the target are identified by using a neural network presenting competitive learning technique. The winning neuron is trained to approximate to the target and, then, pursuit it. A digital camera provides a sequence of images and the algorithm process those frames in real time tracking the moving target. The algorithm is performed both with black and white and multi-colored images to simulate real world situations. Results show the effectiveness of the proposed algorithm, since the neurons tracked the moving targets even if there is no pre-processing image analysis. Single and multiple moving targets are followed in real time.
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Purpose: The present study aimed to evaluate an injectable extended-release formulation of prednisolone acetate (PA) for orbital administration. Methods: Microspheres (MEs) of poly-ε-caprolactone (PCL) containing PA were developed by the method of solvent evaporation. The MEs obtained were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), encapsulation efficiency and in vitro release profile. The in vivo release profile was evaluated in rabbits after periocular injection of an aqueous suspension of MEs. The local biocompatibility of the system was verified by histopathologic analysis of the deployment region. Results: After MEs preparation, morphological analysis by SEM showed the feasibility of the employed method. The content of PA encapsulated was 43 ± 7% and can be considered as satisfactory. The system characterization by DSC technique, in addition to confirm the system stability, did not indicate the existence of interaction between the drug and the polymer. The in vitro release study showed the prolonged-release features of the developed system. Preliminary in vivo study showed the absence of local toxicity and confirmed the prolonged release profile of PA from MEs, suggesting the viability of the developed system for the treatment of orbital inflammatory diseases. Conclusion: The results obtained in this work are relevant and accredit the system developed as a possible alternative to the treatment of inflammatory orbitopathy.
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The purpose of this study was to assess color alteration of the paints used for iris painting in artificial eyes. Five disks of heat cured acrylic resin were confectioned by microwave energy for each paint analyzed, in a total of 40 specimens. Each specimen consisted of a colorless acrylic resin disk and another of equal size, of scleral white colored acrylic resin, with the painting interposed between the two disks. The specimens were submitted to an accelerated aging process in a chamber under ultraviolet radiation for 1,008 hours. To assess color variation, a reflective spectrophotometer was used. The results were statistically analyzed by ANOVA and the Tukey test (p < 0.05). All the paints underwent chromatic alteration. The oil paint presented the highest resistance to accelerated aging.
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Anurans may be brightly colored or completely cryptic. Generally, in the former situation, we are dealing with aposematism, and the latter is an example of camouflage. However, these are only simple views of what such colorations really mean and which defensive strategy is implied. For instance, a brightly colored frog may be part of a mimicry ring, which could be either Batesian, Müllerian, or Browerian. These are only examples of the diversity of color-usage systems as defensive strategies. Unfortunately, reports on the use of colors as defensive mechanisms are widespread in the available literature, and the possible functions are rarely mentioned. Therefore, we reviewed the literature and added new data to this subject. Then, we the use of colors (as defensive mechanism) into categories. Mimicry was divided into the subcategories camouflage, homotypy, and nondeceitful homotypy, and these groups were also subcategorized. Dissuasive coloration was divided into behavioral display of colors, polymorphism, and polyphenism. Aposematism was treated apart, but aposematic colorations may be present in other defensive strategies. Finally, we propose functions and forms of evolution for some color systems in post-metamorphic anurans and hope that this review can be the basis for future research, even on other animal groups. © 2009 L. F. Toledo and C. F. B. Haddad.
SEM-EDS and biomechanical evaluation of implants with different surface treatments: An initial study
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Aim: Alterations in implant surfaces can affect periimplant bone formation and shorten the healing time. The goal of the present study was a comparative scanning electron microscopy (SEM)/energy dispersive spectrometry (EDS) and biomechanical evaluation of implants subjected to different surface treatments. Materials and Methods: Four implant surfaces were analyzed in the present study: machined commercial implants (TU); porous-surfaced commercial implants blasted with Al2O3 microspheres and acid-etched (TJA); laser beam-irradiated experimental implants (Laser) and laser beam-irradiated experimental implants with hydroxyapatite coating (HA). One sample for each surface underwent pre-surgery SEM/EDS analysis. Thirty-two implants (8 for each surface treatment) were then inserted into the tibia of 4 rabbits. After 8 weeks, the animals were euthanized and the implants retrieved by reverse torque and processed for post-surgery SEM/EDS analysis. Results: HA implants presented higher removal torque values when compared to Laser, TJA and TU groups. Post-surgery SEM micrographs clearly showed bone formation on all the examined surfaces; however, in the TU group bone covered only some areas of the implant surface, while in TJA, Laser and HA groups the entire implant surfaces were overlaid by newly formed bone. EDS analysis supported the results obtained by SEM and removal torque, showing that concentration of Ca and P increased from TU to TJA, Laser and HA implants. Conclusions: Implants with surfaces modified by laser beam with or without apatite coating showed more promising results.
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The aim of this study was to evaluate the expression of osteocalcin protein during the alveolar bone healing process in rats. Twenty four rats were used in this study and, after anesthetic induction, they had their right upper incisors extracted. At 7, 14, 21 and 28 days after the tooth extraction, the animals were injected 4% formaldehyde. The histological tissue pieces were colored in hematoxilin and eosin and the immunohistochemistry reaction for osteocalcin was performed. At seven days lesser neoformed trabeculae bone and a small quantity of osteocalcin labeling were observed. At 14 and 21 days a larger quantity of neoformed trabeculae bone and higher osteocalcin values were detected. At 28 days the largest quantity of neoformed trabeculae bone and a decrease on the amount of osteocalcin immunolabelling were noticed. According to our results and considering the limits of the present study it is possible to conclude that a greater osteocalcin expression is observed at 14 and 21 days postoperatively, characterizing the periods when intense mineralization of the bone tissue occurs during the alveolar bone healing process.