805 resultados para Fish Collagen


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Objectives: To analyze the presence and distribution of collagen fibers and versican in human vocal fold lamina propria of fetal larynges. Study Design: Cross sectional analysis of cadaveric vocal folds of human fetuses. Methods: Seven fetal larynges obtained from 28- to 36-week-old fetuses were analyzed with the Picrosirius-polarization method, immunohistochemistry, and image analysis. Results: Collagen fibers within the lamina propria exhibited a monolaminar distribution pattern and spatial arrangement in ""wicker basket."" Versican distribution was larger in the superficial and intermediate layers when compared to the deep layer. Conclusion: Our findings suggest that collagen and versican distribution and arrangement within the lamina propria in the developing fetus are important for vocalization at birth.

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Background Collagen V shows promise as an inducer of interstitial lung fibrosis in experimental systemic sclerosis (SSc). Materials and methods Remodelling of the pulmonary interstitium was evaluated based on the clinical data and open lung biopsies from 15 patients with SSc. Normal lung tissues obtained from eight individuals who died of traumatic injuries were used as control group. Immunofluorescence, immunohistochemistry, morphometry, tri-dimensional reconstruction and a real-time polymerase chain reaction were used to evaluate the quantity, structure and molecular chains of collagen V. The impact of these markers was tested on clinical data. Results The main difference in collagen V content between SSc patients and the control group was an increased, abnormal and distorted fibre deposition in the alveolar septa and the pre-acinar artery wall. The lungs from SSc patients presented [alpha 1(V)] and [alpha 2(V)] mRNA chain expression increased, but [alpha 2(V)] was proportionally increased compared with the control group. High levels of collagen V were inversely associated with vital capacity (r = -0.72; P = 0.002), forced vital capacity (r = -0.76; P < 0.001), forced expiratory volume in 1-s (r = -0.89; P < 0.001) and diffusing capacity for carbon monoxide (r = -0.62; P = 0.04). Conclusions Abnormal collagen V fibres are overproduced in lungs from SSc patients and may play an important role in the pathogenesis of the disease as this molecule regulates tissue collagen assembly. The aberrant histoarchitecture observed in SSc can be related to the overexpression of the [alpha 2(V)] gene of unknown origin.

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PURPOSE: To evaluate the safety and efficacy of corneal collagen crosslinking (CXL) in patients with painful pseudophakic bullous keratopathy (PBK). SETTING: University of Sao Paulo, Sao Paulo and Sadalla Amin Ghanem Eye Hospital, Joinville, Santa Catarina, Brazil. METHODS: This prospective study included consecutive eyes with PBK that had CXL. After a 9.0 mm epithelial removal, riboflavin 0.1% with dextran 20% was applied for 30 minutes followed by ultraviolet-A irradiation (370 nm, 3 mW/cm(2)). Therapeutic contact lenses were placed for 1 week. Corneal transparency, central corneal thickness (CCT), and ocular pain were assessed preoperatively and 1 and 6 months postoperatively. Statistical analysis was by paired t tests. RESULTS: Fourteen patients (14 eyes) with a mean age 71.14 years +/- 11.70 (SD) (range 53 to 89 years) were enrolled. Corneal transparency was better in all eyes 1 month after surgery. At 6 months, corneal transparency was similar to preoperative levels (P = .218). The mean CCT was 747 mu m preoperatively and 623 mu m at 1 month; the decrease was statistically significant (P<.001). At 6 months, the mean CCT increased to 710 mu m, still significantly thinner than preoperatively (P = .006). Pain scores at 6 months were not significantly different than preoperatively (P = .066). CONCLUSIONS: Corneal CXL significantly improved corneal transparency, corneal thickness, and ocular pain 1 month postoperatively. However, it did not seem to have a long-lasting effect in decreasing pain and maintaining corneal transparency in patients with PBK.

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In ostariophysan fish, the detection of alarm substance released from the skin of a conspecific or a sympatric heterospecific may elicit alarm reactions or antipredator behavioral responses. In this study, experiments were performed to characterize and quantify the behavioral response threshold of Leporinus piau, both individually and in schools, to growing dilutions of conspecific (CAS) and heterospecific skin extract (HAS). The predominant behavioral response to CAS stock stimulation was biphasic for fish held individually, with a brief initial period of rapid swimming followed by a longer period of immobility or reduced swimming activity. As the dilution of skin extract was increased, the occurrence and magnitude of the biphasic alarm response tended to decrease, replaced by a slowing of locomotion. Slowing was the most common antipredator behavior, observed in 62.5% of animals submitted to HAS stimulation. School cohesion, measured as proximity of fish to the center of the school, and swimming activity near the water surface significantly increased after exposure to CAS when compared with the control group exposed to distilled water. Histological analysis of the epidermis revealed the presence of Ostariophysi-like club cells. The presence of these cells and the behavioral responses to conspecific and heterospecific skin extract stimulation suggest the existence of a pheromone alarm system in L. piau similar to that in Ostariophysi, lending further support for the neural processing of chemosensory information in tropical freshwater fish.

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The present study provides a detailed description of morphological and hodological aspects of the glomerular nucleus in the weakly electric fish Gymnotus sp., and explores the evolutionary and functional implications flowing from this analysis. The glomerular nucleus of Gymnotus shows numerous morphological similarities with the glomerular nucleus of percomorph fish, although cytoarchitectonically simpler. In addition, congruence of the histochemical acetylcholinesterase (AChE) distribution with cytoarchitectonic data suggests that the glomerular nucleus, together with the ventromedial cell group of the medial subdivision of the preglomerular complex (PGm-vmc) rostrally, and the subglomerular nucleus (as identified by Maler et al. [1991] J Chem Neuroanat 4:1-38) caudally, may form a distinct longitudinally organized glomerular complex. Our results show that an important source of sensory afferents to the glomerular nucleus originates in the pretectal and electrosensorius nuclei. The glomerular nucleus in turn projects to the hypothalamus (inferior lobe and anterior hypothalamus), to the anterior tuberal nucleus, and to the medial region of the preglomerular nucleus (PGm). These data suggest that visual and electrosensory information reach the glomerular nucleus and are relayed to the hypothalamus and, via PGm, to the pallium. Such connections are similar to those of the glomerular nucleus in percomorphs and the posterior pretectal nucleus in osteoglossomorph, esocids, and salmonids, where they comprise one component of a visual processing pathway. In Gymnotiform fish, however, the pretectal region that projects to the glomerular nucleus is dominated by electrosensory input (visual input is minor), which is consistent with the dominant role of electroreception in these fish. J. Comp. Neurol. 519:1658-1676, 2011. (c) 2011 Wiley-Liss, Inc.

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Few studies has been done using guided bone regeneration in maxillary sinus defects. Aim: To assess the bone repair process in surgical defects on the alveolar wall of the monkey maxillary sinus, which communicates with the sinus cavity, by using collagen membranes: Gen-derm - Genius Baumer, Pro-tape - Proline and autologous temporal fascia. Materials and Methods: In this prospective and experimental study, orosinusal communications were performed in four tufted capuchin monkeys (Cebus apella) and histologic analysis was carried out 180 days after. Results: In the defects without a cover (control), bone proliferation predominated in two animals and fibrous connective tissue predominated in the other two. In defects repaired with a temporal fascia flap, fibrous connective tissue predominated in three animals and bone proliferation predominated in one. In the defects repaired with Gen-derm or Pro-tape collagen membranes there was complete bone proliferation in three animals and fibrous connective tissue in one. Conclusions: Surgical defect can be repaired with both bone tissue and fibrous connective tissue in all study groups; collagen membranes was more beneficial in the bone repair process than temporal fascia or absence of a barrier.

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OBJECTIVES To evaluate the histological alterations of extracellular matrix in long-term alloxan-induced diabetes and aging urethras of male rats with descriptions of total connective tissue, muscle layer and collagen types I and III relative amounts. METHODS Histologic evaluations were performed in 3 animal groups: group 1, 8 weeks old; group 2, 44 weeks old; and group 3, 44 weeks old with alloxan-induced diabetes. The muscle layer thickness, extracellular matrix fibrosis, and collagen were quantified on digital images of the urethral samples. RESULTS A higher total thickness and muscle layer thickness and higher connective tissue and collagen content were observed in the urethras of group 3. No changes in the collagen type III/I ratio were found in the urethra of groups 2 and 3. CONCLUSIONS Our results suggest that the morphologic alterations of the urethra should also be considered in long-term studies of diabetic lower urinary tract dysfunction. These morphologic alterations due to diabetes differ from the changes induced by aging itself and could represent a final stage in decompensate urethras. Further studies are necessary to establish the real influence of the urethral morphologic changes on lower urinary tract diabetes dysfunction. UROLOGY 77: 510.e6-510.e11, 2011. (C) 2011 Elsevier Inc.

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LipL32 is the major leptospiral outer membrane lipoprotein expressed during infection and is the immunodominant antigen recognized during the humoral immune response to leptospirosis in humans. In this study, we investigated novel aspects of LipL32. In order to define the immunodominant domains(s) of the molecule, subfragments corresponding to the N-terminal, intermediate, and C-terminal portions of the UpL32 gene were cloned and the proteins were expressed and purified by metal affinity chromatography. Our immunoblot results indicate that the C-terminal and intermediate domains of LipL32 are recognized by sera of patients with laboratory-confirmed leptospirosis. An immunoglobulin M response was detected exclusively against the LipL32 C-terminal fragment in both the acute and convalescent phases of illness. We also evaluated the capacity of LipL32 to interact with extracellular matrix (ECM) components. Dose-dependent, specific binding of LipL32 to collagen type IV and plasma fibronectin was observed, and the binding capacity could be attributed to the C-terminal portion of this molecule. Both heparin and gelatin could inhibit LipL32 binding to fibronectin in a concentration-dependent manner, indicating that the 30-kDa heparin-binding and 45-kDa gelatin-binding domains of fibronectin are involved in this interaction. Taken together, our results provide evidence that the LipL32 C terminus is recognized early in the course of infection and is the domain responsible for mediating interaction with ECM proteins.