989 resultados para Iris - Vessels
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A vascularização arterial do timo (número, origem e ordenação) bem como a distribuição parenquimal dos ramos penetrantes foram estudadas em 40 aves da linhagem Paraíso Pedrês. Trinta aves foram injetadas com látex e dissecadas, enquanto 10 aves tiveram seus sistemas arteriais injetados com resina (metil metacrilato e mercox) para a preparação de moldes vasculares. A principal fonte de irrigação encontrada foi a associação dos ramos oriundos das artérias comuns do nervo vago, tireóideas e ingluviais, sendo que seus ramos penetravam o parênquima dos lobos, principalmente pelas suas extremidades cranial e caudal. A partir da penetração, os ramos tímicos apresentavam distribuição predominante para a periferia do lobo, formando uma trama capilar poligonal, com espaços irregulares, característica de um órgão linforreticular.
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Foi proposta uma revisão das terminologias empregadas para a descrição das alterações renais e também sugerida uma classificação em estágios para a doença renal crônica à semelhança da medicina humana pela IRIS (International Renal Interest Society). Essa classificação considera os estágios da doença de acordo com o tempo de evolução e a presença de marcadores de lesão renal. O objetivo principal é auxiliar no estabelecimento do diagnóstico, do prognóstico e da terapia adequada conforme cada estágio e, assim, retardar a perda da função dos rins e a evolução da doença renal e, dessa forma, propiciar melhor qualidade de vida ao paciente.
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Background: Lignin and hemicelluloses are the major components limiting enzyme infiltration into cell walls. Determination of the topochemical distribution of lignin and aromatics in sugar cane might provide important data on the recalcitrance of specific cells. We used cellular ultraviolet (UV) microspectrophotometry (UMSP) to topochemically detect lignin and hydroxycinnamic acids in individual fiber, vessel and parenchyma cell walls of untreated and chlorite-treated sugar cane. Internodes, presenting typical vascular bundles and sucrose-storing parenchyma cells, were divided into rind and pith fractions. Results: Vascular bundles were more abundant in the rind, whereas parenchyma cells predominated in the pith region. UV measurements of untreated fiber cell walls gave absorbance spectra typical of grass lignin, with a band at 278 nm and a pronounced shoulder at 315 nm, assigned to the presence of hydroxycinnamic acids linked to lignin and/or to arabino-methylglucurono-xylans. The cell walls of vessels had the highest level of lignification, followed by those of fibers and parenchyma. Pith parenchyma cell walls were characterized by very low absorbance values at 278 nm; however, a distinct peak at 315 nm indicated that pith parenchyma cells are not extensively lignified, but contain significant amounts of hydroxycinnamic acids. Cellular UV image profiles scanned with an absorbance intensity maximum of 278 nm identified the pattern of lignin distribution in the individual cell walls, with the highest concentration occurring in the middle lamella and cell corners. Chlorite treatment caused a rapid removal of hydroxycinnamic acids from parenchyma cell walls, whereas the thicker fiber cell walls were delignified only after a long treatment duration (4 hours). Untreated pith samples were promptly hydrolyzed by cellulases, reaching 63% of cellulose conversion after 72 hours of hydrolysis, whereas untreated rind samples achieved only 20% hydrolyzation. Conclusion: The low recalcitrance of pith cells correlated with the low UV-absorbance values seen in parenchyma cells. Chlorite treatment of pith cells did not enhance cellulose conversion. By contrast, application of the same treatment to rind cells led to significant removal of hydroxycinnamic acids and lignin, resulting in marked enhancement of cellulose conversion by cellulases.
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The tree Gmelina arborea has been widely introduced in Costa Rica for commercial purposes. This new conditions for melina cause variations on anatomy in secondary xylem of the trees growing in plantations. The objective of the present research was to determine the variation in the anatomy of xylem caused by the ecological conduction variation. Dimensions of fiber, axial parenchyma percentage of cross sections, parameters of vessels and the ray were measured. The results showed that some anatomical characteristics remained stable despite variations of ecological conditions, especially radial parenchyma and anatomical features which were less affected by the altitude. On the other hand, the vessels, axial parenchyma and fiber were less stable because they were affected significantly by the longitude, latitude, altitude and precipitation. Latitude significantly affected vessel percentage, length and diameter of the fiber and lumen. Longitude affected vessel percentage and fiber diameter. Altitude had a significant correlation with the amount of cells at my height. Annual average precipitation affected vessel percentage and diameter, not only of the fiber, but also of the lumen. These results suggest that the new growth conditions of G. arborea trees in Costa Rica have produced an anatomic adaptation.
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The objective of this study was to show the radial variation of some anatomic characteristics, wood density and natural durability of teak (Tectona grandis L.F.) growing in Costa Rica. Samples of trees 13 years old were obtained from two growing sites (high and low growing) of plantations established in a humid tropical climate (CHT) and dry tropical climate (CST). The variables measured of the fibers as well as for the rays were not affected by the climate or the type of growing site, except for the length of the fibers. The fibers of teak wood from the best growing site were significantly larger. Vessels were found with a greater frequency for the CST but mostly solitary in comparison with the CBT. Average density, maximum density and the variation within the ring presented a light higher magnitude for the CST. The quality of the growing site did not affect these variables. The resistance of fungus attack was similar in the area of heartwood near the pith compared to the heartwood near the sapwood for all the conditions evaluated. Nevertheless, it was observed in some trees a similar resistance of fungus attack for areas of sapwood compared to similar areas of heartwood.
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This work evaluated the wood anatomical and physical characteristics of 24 months-old Eucalyptus grandis trees, planted in 3x2m spacing and fertilized with nitrogen (6, 12, 18 month old) and sewage sludge (planting, 8 month old). For each treatment 10 eucalypts trees were cut according to the distribution of basal area. Wood samples were collected in different percentages of the total height to analyze the anatomical (vessels and fibers) and physical (wood density) characteristics. The results showed that the wood apparent density and wood basic density of the eucalypt trees in the nitrogen and sewage sludge were larger in comparison to the control. Radial profiles of wood apparent density, were similar in the three treatments, presenting the exected characteristics of juvenile wood of 24 months-old eucalypt trees. Fiber and vessel dimensions were not affected by fertilization.
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Background: Minimally invasive techniques have been revolutionary and provide clinical evidence of decreased morbidity and comparable efficacy to traditional open surgery. Computer-assisted surgical devices have recently been approved for general surgical use. Aim: The aim of this study was to report the first known case of pancreatic resection with the use of a computer-assisted, or robotic, surgical device in Latin America. Patient and Methods: A 37-year-old female with a previous history of radical mastectomy for bilateral breast cancer due to a BRCA2 mutation presented with an acute pancreatitis episode. Radiologic investigation disclosed an intraductal pancreatic neoplasm located in the neck of the pancreas with atrophy of the body and tail. The main pancreatic duct was enlarged. The surgical decision was to perform a laparoscopic subtotal pancreatectomy, using the da Vinci (R) robotic system (Intuitive Surgical, Sunnyvale, CA). Five trocars were used. Pancreatic transection was achieved with vascular endoscopic stapler. The surgical specimen was removed without an additional incision. Results: Operative time was 240 minutes. Blood loss was minimal, and the patient did not receive a transfusion. The recovery was uneventful, and the patient was discharged on postoperative day 4. Conclusions: The subtotal laparoscopic pancreatic resection can safely be performed. The da Vinci robotic system allowed for technical refinements of laparoscopic pancreatic resection. Robotic assistance improved the dissection and control of major blood vessels due to three-dimensional visualization of the operative field and instruments with wrist-type end-effectors.
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Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasia and currently well recognized as a distinct entity with characteristic morphological, immunohistochemical and molecular findings. We report a case of PEComa arising in the antrum of a 71-year-old female with melena. The tumor, located predominantly in the submucosa as a well delimited nodule, measured 3.0 cm in diameter and was completely resected, with no evidence of the disease elsewhere. Histologically, it was composed predominantly of eosinophilic epithelioid cells arranged in small nests commonly related to variably sized vessels, with abundant extracellular material, moderate nuclear variation and discrete mitotic activity. No necrosis, angiolymphatic invasion or perineural infiltration was seen. Tumor cells were uniformly positive for vimentin, smooth muscle actin, desmin and melan A. Although unusual, PEComa should be considered in the differential diagnosis of gastric neoplasia with characteristic epithelioid and oncocytic features and prominent vasculature: (C) 2010 Baishideng. All rights reserved.
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Background. Antilipoprotein lipase (anti-LPL) antibodies were described in rheumatic diseases. In systemic lupus erythematosus they were highly associated with inflammatory markers and dyslipidemia, and may ultimately contribute to vascular damage. The relevance of this association in Takayasu's arteritis, which is characterized by major inflammatory process affecting vessels, has not been determined. Objectives. To analyze the presence of anti-LPL antibodies in patients with Takayasu's arteritis and its association with inflammatory markers and lipoprotein risk levels. Methods. Thirty sera from patients with Takayasu's arteritis, according to ACR criteria, were consecutively included. IgG anti-LPL was detected by a standard ELISA. Lipoprotein risk levels were evaluated according to NCEP/ATPIII. Inflammatory markers included ESR and CRP values. Results. Takayasu's arteritis patients had a mean age of 34 years old and all were females. Half of the patients presented high ESR and 60% elevated CRP. Lipoprotein NCEP risk levels were observed in approximately half of the patients: 53% for total cholesterol, 43% for triglycerides, 16% for HDL-c and 47% for LDL-c. In spite of the high frequency of dyslipidemia and inflammatory markers in these patients no anti-LPL were detected. Conclusions. The lack of anti-LPL antibodies in Takayasu's disease implies distinct mechanisms underlying dyslipidemia compared to systemic lupus erythematosus. Copyright (C) 2009 Jozelio Freire de Carvalho et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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Background: Progression of atherosclerosis in coronary artery disease is observed through consecutive angiograms. Prognosis of this progression in patients randomized to different treatments has not been established. This study compared progression of coronary artery disease in native coronary arteries in patients undergoing surgery, angioplasty, or medical treatment. Methods: Patients (611) with stable multivessel coronary artery disease and preserved ventricular function were randomly assigned to CABG, PCI, or medical treatment alone (MT). After 5-year follow-up, 392 patients (64%) underwent new angiography. Progression was considered a new stenosis of >= 50% in an arterial segment previously considered normal or an increased grade of previous stenosis > 20% in nontreated vessels. Results: Of the 392 patients, 136 underwent CABG, 146 PCI, and 110 MT. Baseline characteristics were similar among treatment groups, except for more smokers and statin users in the MT group, more hypertensives and lower LDL-cholesterol levels in the CABG group, and more angina in the PCI group at study entry. Analysis showed greater progression in at least one native vessel in PCI patients (84%) compared with CABG (57%) and MT (74%) patients (p < 0.001). LAD coronary territory had higher progression compared with LCX and RCA (P < 0.001). PCI treatment, hypertension, male sex, and previous MI were independent risk factors for progression. No statistical difference existed between coronary events and the development of progression. Conclusion: The angioplasty treatment conferred greater progression in native coronary arteries, especially in the left anterior descending territories and treated vessels. The progression was independently associated with hypertension, male sex, and previous myocardial infarction.
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Background: Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. Results: Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 10(7) recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. Conclusions: This study indicates that immunoisolation devices containing endostatin-expressing cells are effective for the inhibition of the growth of melanoma and Ehrlich tumors. Macroencapsulation of engineered cells is therefore a reliable platform for the refinement of innovative therapeutic strategies against tumors.
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Sinovitis in Scleroderma (SSc) is rare, usually aggressive and fully resembles rheumatoid arthritis. Experimental models of SSc have been used in an attempt to understand its pathogenesis. Previous studies done in our laboratory had already revealed the presence of a synovial remodeling process in rabbits immunized with collagen V. To validate the importance of collagen type V and to explore the quantitative relationship between this factor and synovia remodeling as well as the relationship between collagen type V and other collagens, we studied the synovial tissue in immunized rabbits. Rabbits (N= 10) were immunized with collagen V plus Freund's adjuvant and compared with animals inoculated with adjuvant only (N= 10). Synovial tissues were submitted to histological analysis, immunolocalization to collagen I, III and V and biochemical analysis by eletrophoresis, immunoblot and densitometric method. The synovial tissue presented an intense remodeling process with deposits of collagen types I, III and V after 75 and 120 days of immunization, mainly distributed around the vessels and interstitium of synovial extracellular matrix. Densitometric analysis confirmed the increased synthesis of collagen I, III and V chains (407.69 +/- 80.31; 24.46 +/- 2.58; 70.51 +/- 7.66, respectively) in immunized rabbits when compared with animals from control group (164.91 +/- 15.67; 12.89 +/- 1.05; 32 +/- 3.57) (p<0.0001). We conclude that synovial remodeling observed in the experimental model can reflect the articular compromise present in patients with scleroderma. Certainly, this experimental model induced by collagen V immunization will bring new insights in to pathogenic mechanisms and allow the testing of new therapeutic strategies to ameliorate the prognosis for scleroderma patients.
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Background: Lymph node metastasis in endometrial cancer significantly decreases survival rate. Few data on the influence of intratumoral lymphatic microvessel density (LMVD) on survival in endometrial cancer are available. Our aim was to assess the intratumoral LMVD of endometrial carcinomas and to investigate its association with classical pathological factors, lymph node metastasis and survival. Methods: Fifty-seven patients with endometrial carcinoma diagnosed between 2000 and 2008 underwent complete surgical staging and evaluation of intratumoral LMVD and other histologic variables. Lymphatic microvessels were identified by immunohistochemical staining using monoclonal antibody against human podoplanin (clone D2-40) and evaluated by counting the number of immunostained lymphatic vessels in 10 hot spot areas at 400x magnification. The LMVD was expressed by the mean number of vessels in these 10 hot spot microscopic fields. We next investigated the association of LMVD with the clinicopathologic findings and prognosis. Results: The mean number of lymphatic vessels counted in all cases ranged between 0 and 4.7. The median value of mean LMVD was 0.5, and defined the cut-off for low and high LMVD. We identified low intratumoral LMVD in 27 (47.4%) patients and high LMVD in 30 (52.6%) patients. High intratumoral LMVD was associated with lesser miometrial and adnaexal infiltration, lesser cervical and peritoneal involvement, and fewer fatal cases. Although there was lower lymph node involvement among cases with high LMVD, the difference did not reach significance. No association was seen between LMVD and FIGO staging, histological type, or vascular invasion. On the other hand, low intratumoral LMVD was associated with poor outcome. Seventy-five percent of deaths occurred in patients with low intratumoral LMVD. Conclusion: Our results show association of high intratumoral LMVD with features related to more localized disease and better outcome. We discuss the role of lymphangiogenesis as an early event in the endometrial carcinogenesis.
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Background: The purpose of this study was to evaluate collagen deposition, mRNA collagen synthesis and TGFbeta expression in the lung tissue in an experimental model of scleroderma after collagen V-induced nasal tolerance. Methods: Female New Zealand rabbits (N = 12) were immunized with 1 mg/ml of collagen V in Freund's adjuvant (IM). After 150 days, six immunized animals were tolerated by nasal administration of collagen V ( 25 mu g/day) (IM-TOL) daily for 60 days. The collagen content was determined by morphometry, and mRNA expressions of types I, III and V collagen were determined by Real-time PCR. The TGF-beta expression was evaluated by immunostaining and quantified by point counting methods. To statistic analysis ANOVA with Bonferroni test were employed for multiple comparison when appropriate and the level of significance was determined to be p < 0.05. Results: IM-TOL, when compared to IM, showed significant reduction in total collagen content around the vessels (0.371 +/- 0.118 vs. 0.874 +/- 0.282, p < 0.001), bronchioles (0.294 +/- 0.139 vs. 0.646 +/- 0.172, p < 0.001) and in the septal interstitium (0.027 +/- 0.014 vs. 0.067 +/- 0.039, p = 0.026). The lung tissue of IM-TOL, when compared to IM, showed decreased immunostaining of types I, III and V collagen, reduced mRNA expression of types I (0.10 +/- 0.07 vs. 1.0 +/- 0.528, p = 0.002) and V (1.12 +/- 0.42 vs. 4.74 +/- 2.25, p = 0.009) collagen, in addition to decreased TGF-beta expression ( p < 0.0001). Conclusions: Collagen V-induced nasal tolerance in the experimental model of SSc regulated the pulmonary remodeling process, inhibiting collagen deposition and collagen I and V mRNA synthesis. Additionally, it decreased TGF-beta expression, suggesting a promising therapeutic option for scleroderma treatment.
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Purpose: To evaluate the effects of Triesence (R) (TRI), a new preservative-free triamcinolone approved by the U. S. Food and Drug Administration (FDA) for intraocular use, on human retina pigment epithelial (ARPE-19) and rat neurosensory (R28) cells in culture. Methods: ARPE-19 and R28 cell cultures were treated 24 h with 1,000, 500, 200, or 100 mu g/mL of crystalline (cTRI) or 1,000, 500, or 200 mu g/mL of solubilized (sTRI). TRI was solubilized by centrifuging the drug, discarding the supernatant containing the vehicle and then resuspending the drug pellet in an equivalent amount of Dimethyl sulfoxide to achieve the same concentration as the commercial preparation. Percentage of cell viability (CV) was evaluated by a trypan blue dye-exclusion assay. The mitochondrial membrane potential (Delta Psi m) was analyzed with the JC-1 assay. The caspase-3/7 activity was measured by a fluorochrome assay. Results: In the ARPE-19 cultures, the cTRI caused a decrease in CV at 1,000 mg/mL (13.03 +/- 6.51; P < 0.001), 500 mu g/mL (28.87 +/- 9.3; P < 0.001), 200 mu g/mL (54.93 +/- 5.61; P < 0.001), and 100 mu g/mL (82.53 +/- 0.65; P < 0.005) compared with the untreated controls (96.98 +/- 0.16). In R28 cultures, the cTRI treatment also reduced CV values significantly (P < 0.001) for the 1,000 mu g/mL (22.73 +/- 2.44), 500 mu g/mL (34.63 +/- 1.91), 200 mu g/mL (58.70 +/- 1.39), and 100 mu g/m (75.33 +/- 2.47) compared with the untreated controls (86.08 +/- 3.54). Once the TRI was solubilized (sTRI), the CV and Delta Psi m remained similar to the untreated controls for both ARPE-19 and R28 cells. The sTRI treatment with 1,000, 500, and 200 mu g/mL increased in caspase-3/7 activity in ARPE-19 cells (P < 0.01) and in R28 cells (P < 0.05) compared with dimethyl sulfoxide equivalent controls. Conclusion: The crystalline form of TRI (cTRI) can cause a significant decrease in CV to cultured retinal cells. Once the TRI is solubilized (sTRI), at the same concentrations, the cells remain viable with no decrease in CV or Delta Psi m. The sTRI can, however, increase caspase-3/7 activity, thus suggesting some degree of apoptosis.