988 resultados para Preneoplastic and neoplastic lesions
Resumo:
In the present study, the effects of electrolytic lesions of the anteroventral third ventricle (AV3V) region and of the medial forebrain bundle (MFB) on the pressor response induced by bilateral carotid occlusion (BCO) in conscious intact and aortic baroreceptor-denervated (AD) rats were investigated. In intact control rats, BCO during 60 s produced a pressor response that could be divided into an early response (ER = 50 +/- 3 mmHg) that reachs a peak during the first 20 s and a sustained late response (LR), smaller than ER (32 +/- 2 mmHg), observed during the last 30 s. In intact-innervated rats, AV3V lesion (2 days) reduced ER (22 +/- 3 mmHg) and LR (16 +/- 2 mmHg), whereas the bilateral MFB lesions (6 days) mainly reduced LR (9 +/- 1 mmHg). Rats with simultaneous lesion of both the AV3V region and the MFB showed additional reduction of the ER (15 +/- 3 mmHg), but not LR (11 +/- 1 mmHg) when compared to the effect of MFB lesions alone. Compared to the AV3V lesion alone, LR but not ER was reduced in rats with a double lesion. In sham-lesioned rats, AD induced a significant increase in the pressor response to BCO (ER = 75 +/- 4 mmHg and LR = 65 +/- 3 mmHg) when compared to intact controls. A similar reduction in ER and LR was observed in AD rats after AV3V (ER = 35 +/- 3 mmHg and LR = 40 +/- 2 mmHg) and MFB (ER = 49 +/- 6 mmHg and LR = 41 +/- 5 mmHg) lesions alone or combined (ER = 40 +/- 6 mmHg and LR = 35 +/- 7 mmHg). The results showed that simultaneous lesions of both the AV3V region and the MFB practically abolished the pressor response to BCO. They also suggested that aortic baroreceptor activity plays a significant role in the effects of AV3V and MFB lesions on the pressor response to BCO.
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Pollution, industrial solvents, concentrations of metals and other environmental agents are widely related to biochemicals values which are used in disease diagnosis of environmental toxicity. A rat bioassay validated for the identification of toxic effects of eutrophication revealed increased serum activities of amylase, alanine transaminase (BLT) and alkaline phosphatase (ALP) in rats that received algae, filtered water and nickel or cadmium from drinking water. Serum Cu-Zn superoxide dismutase activity decreased from its basal level of 40.8 +/- 2.3 to 26.4 U/mg protein, at 7 days of algae and at 48 hr of nickel and cadmium water ingestion. The observation that lipoperoxide concentration was not altered in rats treated with filtered water, while amylase, ALT and ALP were increased in these rats and in those treated with nickel or cadmium, indicated that pancreatic, hepatic and osteogenic lesions by eutrophication were not related to superoxide radicals, and might be due to a novel toxic environmental agent found in filtered and non-filtered algae water.
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Taking into consideration that glutatione S-transferase (GST) and cellular proliferation play a crucial role during carcinogenesis, the goal of this study was to investigate the expression of placental GST, called GST-P, and proliferating cellular nuclear antigen (PCNA) by means of immunohistochemistry during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide (4NQO). This is a useful model for studying oral squamous cell carcinoma phase by phase. Male Wistar rats were distributed into three groups of 10 animals each and treated with 50 ppm 4NQO solution by drinking water for 4, 12 or 20 weeks. Ten animals were used as negative control. GST-P positive foci were detected in non-neoplastic oral cells at 4 weeks of 4NQO administration. In the same way, GST-P positive cells were detected in pre-neoplastic lesions and squamous cell carcinomas induced after 12 and 20 weeks-treatment, respectively. None of the control animals expressed GST-P positive cells. Regarding cellular proliferation, PCNA positive nuclei were higher at 12 and 20 weeks following 4NQO exposure (p < 0.05) when compared to negative control. These results suggest that the expression of GST-P is correlated with cellular proliferation, in which GST-P is associated with risk and progression of oral cancer, whereas PCNA is closely involved during neoplastic conversion. (c) 2007 Published by Elsevier GmbH.
Resumo:
There has been persistent controversy regarding the nature of cell differentiation in alveolar soft-part sarcoma (ASPS) since its first description in 1952. Some studies suggest that ASPS might represent an unusual variant of skeletal muscle tumor, Given the availability of new monoclonal antibodies to probe for skeletal muscle differentiation and the rapid advance in immunocytochemical techniques for deparaffinized, formalin-fixed tissue sections, we wished to test the proposed hypothesis that ASPS might represent a new type of rhabdomyosarcoma Twelve archival samples of ASPS were retrieved, and we investigated the expression of two myogenic regulatory proteins, MyoD1 and myogenin, as rvell as other muscle-associated proteins, using sensitive immunocytochemical techniques. Despite the presence of desmin immunostaining in six ASPSs, no tumors were positive for either muscle actin or myoglobin Most importantly, no specimen showed nuclear expression of MyoD1 or myogenin, In 11 tumors, however, there was considerable granular immunostaining in the tumor cell cytoplasm with the anti-MyoD1 monoclonal antibody 5.8A, a phenomenon observed in various nonmuscle normal and neoplastic tissues with this antibody, To analyze the exact nature of immunostaining of MyoD1 and desmin in ASPS, biochemical analyses using available fresh frozen tumor tissue were performed, Although a 53-kDa band was noted with antidesmin antibody on Western blot analysis, no specific protein band that corresponds to the 45-kDa MyoD1 was detected with antibody 5.8A. These results confirm the presence of desmin in ASPS but argue against authentic expression of MyoD1, They also suggest that the cytoplasmic immunostaining observed with anti-MyoD1 antibody 5.8A most likely represents a nonspecific cross-reaction with an unknown cytoplasmic antigen, Considering the master role that MyoD1 and myogenin play in skeletal muscle commitment and differentiation and the lack of expression of these two proteins in ASPS as determined immunocytochemically and biochemically, we think that the histogenesis of ASPS remains unknown.
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The human papillomavirus (HPV) has been historically associated with head and neck cancers, although its role in oral carcinogenesis remains poorly defined. The purpose of this study was to investigate the prevalence of HPV in mouth floor squamous cell carcinoma and correlate it with clinicopathologic variables, risk factors and survival. HPV presence was evaluated by nested polymerase chain reaction (nPCR) in 29 paraffin-embedded specimens of mouth floor squamous cell carcinoma. HPV DNA was detected in 17.2% (5 of 29) of the specimens; the highest prevalence was observed in non-smoking patients over the age of 60 years. All HPV DNA positive specimens were detected in men with clinical stage III and IV lesions, being most of which were moderately differentiated. Despite this correlation there were no statistically significant differences observed among the analyzed variables, including patients' survival. The relatively low incidence of HPV DNA present in these tumors suggests that this virus does not, by itself, have a significant role in the development of mouth floor squamous cell carcinoma. J Oral Pathol Med (2008) 37: 593-598
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Hand, foot, and mouth disease is a viral infection related to coxsackieviruses A5, A6, A9, and A10, coxsackieviruses B2 and B5, and echovirus 11. It generally affects children, but this article presents a clinical case of a young woman with hand, foot, and mouth disease. Patients with this disease have oral and skin lesions that may be confused with other diseases. The differential diagnosis is very important because both dental and medical professionals may misdiagnose the disease and sometimes prescribe an inappropriate medication.
Resumo:
Atherosclerosis is a very common and important disease being the most important cause of mortality in Brazil. Indeed, in 1995, 23.3% of deaths, all ages, in our country, were the consequence of atherosclerosis. This percentage grows to 26.3% for S. Paulo and 32.7% for Rio Grande do Sul. Morphologically, there are 3 main types of lesions: fatty streaks, fibrous plaques, and complicated lesions. Fatty streaks are inocuous and occur early in life. In some persons, with age, they change into fibrous plaques that may lead to stenosis. They also may become complicated by erosion, calcification, hemorrhage and thrombosis. Atherosclerosis is initiated by endothelial functional alterations responsible for increase in permeability to macromolecules, adhesion, and migration of monocytes-macrophages and lymphocytes plus recruitment of platelets and smooth-muscle medial cells. Adhesion molecules, cytokines, growth factors, and free radicals are locally synthesized, favoring proliferation of extracellular matrix and progression of the lesion. Experimental, clinical, and epidemiological evidence point to the importance of lipids, mainly cholesterol-rich low-density lipoprotein (LDL), as one of the most important molecules involved in the genesis and progression of atherosclerosis. Patients with a genetic disorder of cholesterol metabolism (familial hyperlipidemia), caused by a decrease in the availability of receptors for LDL, develop severe atherosclerosis early in life. A series of other factors, such as age, diabetes melitus, diet, hypertension, lack of exercise, elevated hemocysteinemia, immunological disorders, and coagulation instability, are related to the progression of atherosclerosis. All of them are capable of altering the endothelium or increasing the offer of LDL. All the above-mentioned factors are systemic; but atherosclerosic lesions are focal, located at preferential sites such as the emergence of colaterals, bifurcations, and curvatures of arteries, all areas in which the laminar flow is disturbed. In these areas shear stress is diminished favoring the prolongation of permanence time of lipid particles, cells, cytokines, growth factors, etc., in the vicinity of the endothelium. Moreover, the endothelium has sensors that act as transducers of mechanical forces in biological responses. Experimental data demonstrate that the number and quality of adhesion molecules, cytokines, and growth factors synthetized, as well as the local production of radicals, and pro and anticoagulation factors may change with shear stress favoring or not the local establishment and progression of atherosclerotic lesions.
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The aim of this study was to evaluate the presence of bacterial biofilm on the external surface of the root apex in teeth with pulp necrosis, with and without radiographically visible periapical lesions, and in teeth with a vital pulp. Twenty-one teeth were extracted, eight with pulp necrosis and periapical lesions, eight with pulp necrosis without radiographically visible periapical lesions, and five with a vital pulp. The roots were sectioned, and the root apexes (+/- 3 mm) were processed for scanning electron microscope evaluation. The surface of the apical root was evaluated for the presence of microorganisms, root resorption, and biofilm. There were no microorganisms on the apical root surface of either teeth with pulp vitality or with pulp necrosis with no radiographically visible periapical lesions. Microorganisms were always present in teeth with pulp necrosis and radiographically visible periapical lesions. These included cocci, bacilli, and filaments and the presence of an apical biofilm. Apical biofilm is clinically important because microbial biofilms are inherently resistant to antimicrobial agents and cannot be removed by biomechanical preparation alone. This may cause failure of endodontic treatment as a consequence of persistent infection.
Resumo:
A 6-year-old girl with Glanzmann thrombasthenia presented with caries and periapical lesions in the primary mandibular second molars and moderate gingivitis of the maxillary and mandibular anterior teeth. Dental extraction was recommended, and before every surgical intervention, the patient underwent platelet-concentrate transfusion to prevent hemorrhage. Epsilon aminocaproic acid was administered 6 hours before, and 48 hours after every dental procedure to prevent bleeding. In this case, treatment was effective in the prevention of hemorrhagic complications, during the required dental procedures.
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Renal interstitial fibrosis has been observed in a large number of nephropathies and contributes to the progressive deterioration of renal function. Myofibroblasts have been implicated in the reparative process of tissue injury, including renal scarring secondary to glomerular diseases. We performed a retrospective study on 28 patients with biopsy-proven primary membranous nephropathy, to determine whether interstitial myofibroblasts and tubulointerstitial lesions correlated with renal function at follow-up. Tubulointerstitial pathology was evaluated by morphometric and semiquantitative methods. Interstitial myofibroblasts were counted; 24-hour urinary protein and serum creatinine at the time of diagnosis and at the end of follow-up were available for all the patients. There were 20 males and 8 females, age 2-67 years (mean 42.3±153), most of them with nephrotic syndrome (78.6%). The final renal function had deteriorated in 16 patients (57.1%) and in 5 patients (17.8%) reached end-stage. The renal outcome was correlated with histological changes. We found a positive correlation between the severity of tubulointerstitial damage and the deterioration of the final serum creatinine (r 2=0.185; p=0.016). Myofibroblasts did not predict impaired renal function at the final follow-up. The current data do not support previous suggestions that myofibroblasts are a useful a predictor of end-stage renal disease.
Resumo:
Purpose: To analyze, in vitro, the effects of acetylsalicylic acid (aspirin) and acetic acid solutions on VX2 carcinoma cells in suspension and to examine the correlation between these effects and neoplastic cell death. Methods: The VX2 tumor cells (107 cells/ml) were incubated in solutions containing differing concentrations (2.5% and 5%) of either acetylsalicylic acid or acetic acid, or in saline solution (controls). Every five minutes, cell viability was tested (using the trypan blue test) and analyzed under light microscopy. Results: Tumor cell viability (in %) decreased progressively and, by 30 minutes, neoplastic cell death had occurred in all solutions. Conclusion: Based on this experimental model and the methodology employed, we conclude that these solutions cause neoplastic cell death in vitro.
Resumo:
The purpose of the study was to evaluate the blood serum components and histopathological findings of commercial layers experimentally infected with Salmonella Gallinarum (SG), the microorganism responsible for the fowl typhoid. 180 commercial layers were distributed into three groups (G): G1 and G2 received 0.2mL of inoculum containing 3.3x10 8 and 3.3x10 5 CFU of resistant SG to the nalidix acid (Nal r)/mL, respectively, directly into their crops; G3 did not receive the inoculum (control group). The birds were inoculated when they were 5 days old and the euthanasia was performed 24 hours before and after infection and 3, 5, 7 and 10 days after the administration of the inoculum. In each day of collection, blood samples were obtained for biochemical tests of the blood serum besides macroscopic and histopathological examination of the birds. Data were submitted to analysis of variance by the SAS statistical program and the means were compared by Tukeýs test (P<0,05). In the serum biochemical profile it was observed that the infection interfered in the values of total protein, albumin, calcium, phosphorus, cholesterol, triglycerides, GGT and ALT in the infected groups. The macroscopic examination showed hepatomegaly, alteration of the hepatic color and hemorrhagic spots in the kidneys of animals from G1. The histopathology showed degeneration of hepatocytes in G1 and G2 although other lesions like multifocal hepatic necrosis and inflammatory infiltrate on the liver and kidneys were restricted to G1. The alterations were more evident on G1 which received a higher concentration of bacteria/mL when compared to G2. The results showed that the correlation between biochemical alterations and macroscopic and histopathological lesions can assist the comprehension of the pathophysiology of fowl typhoid, supplying important information for the diagnosis and prognosis of this disease.
Resumo:
This study aimed to assess the performance of International Caries Detection and Assessment System (ICDAS), radiographic examination, and fluorescence-based methods for detecting occlusal caries in primary teeth. One occlusal site on each of 79 primary molars was assessed twice by two examiners using ICDAS, bitewing radiography (BW), DIAGNOdent 2095 (LF), DIAGNOdent 2190 (LFpen), and VistaProof fluorescence camera (FC). The teeth were histologically prepared and assessed for caries extent. Optimal cutoff limits were calculated for LF, LFpen, and FC. At the D 1 threshold (enamel and dentin lesions), ICDAS and FC presented higher sensitivity values (0.75 and 0.73, respectively), while BW showed higher specificity (1.00). At the D 2 threshold (inner enamel and dentin lesions), ICDAS presented higher sensitivity (0.83) and statistically significantly lower specificity (0.70). At the D 3 threshold (dentin lesions), LFpen and FC showed higher sensitivity (1.00 and 0.91, respectively), while higher specificity was presented by FC (0.95), ICDAS (0.94), BW (0.94), and LF (0.92). The area under the receiver operating characteristic (ROC) curve (Az) varied from 0.780 (BW) to 0.941 (LF). Spearman correlation coefficients with histology were 0.72 (ICDAS), 0.64 (BW), 0.71 (LF), 0.65 (LFpen), and 0.74 (FC). Inter- and intraexaminer intraclass correlation values varied from 0.772 to 0.963 and unweighted kappa values ranged from 0.462 to 0.750. In conclusion, ICDAS and FC exhibited better accuracy in detecting enamel and dentin caries lesions, whereas ICDAS, LF, LFpen, and FC were more appropriate for detecting dentin lesions on occlusal surfaces in primary teeth, with no statistically significant difference among them. All methods presented good to excellent reproducibility. © 2012 Springer-Verlag London Ltd.
Resumo:
Bovine enzootic hematuria is characterized by the development of hemangiomatous lesions from several types of neoplastic processes, from epithelial and mesenchymal origin. In this research the histogenesis of neoplastic lesions found in bladder of bovines with enzootic hematuria from Caparaó microregion in the state of Espírito Santo, Brazil was determined. To accomplish this objective, immunohistochemical analysis was performed with primary antibodies: anti-vimentin, anti-cytokeratin, anti-CD31 and anti-uroplakin. Neoplasms found included urothelial carcinoma, in situ carcinoma, adenocarcinoma, hemangioma, myxoma e hemangiosarcoma. Immunohistochemical staining of cytokeratin in epithelial neoplasms and vimentin in mesenchymal neoplasms was significant (p<0.05). CD31 was positive in all the vessels of all samples, however, the staining was significant (p<0.05) in the tumor endothelial cells of the vascular mesenchymal neoplasms, as in hemangiomas and hemangiosarcomas. Uroplakin III staining was uneven in several neoplastic types and showed no significant difference (p>0.05). Most neoplasms showed an atypical uroplakin staining on urothelium and, in the case of hemangiosarcomas there was no staining of the urothelium at all. The Spearman statistical analysis revealed a positive correlation (r= 0.63, p= 0.05) between CD31 and vimentin and between cytokeratin and uroplakin (rs= -0.61, p= 0.05). It was concluded that biomarkers anti-cytokeratin, anti-vimentin and anti-CD31 are important for the diagnosis of neoplasms epithelial, mesenchymal and vascular mesenchymal, respectively. It is possible to use vimentin and CD31 in association in vascular mesenchymal neoplasms and cytokeratin and uroplakin in epithelial neoplasms. The uroplakin is an effective marker, not only for tumor diagnosis, but also to evaluate the urothelial integrity.
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Chilodonelids are small ciliated protozoans found worldwide and can be dangerous in culture conditions. This study presents morphometric data on the ciliate Chilodonella that is found in cultured Nile tilapia (Oreochromis niloticus), native bait fish tuvira (Gymnotus aff. inaequilabiatus) and native pacu (Piaractus mesopotamicus) and includes a histopathological assessment of the changes that occur in the pacu. For parasitic diagnosis, skin and gill samples were scraped onto slides, dried at room temperature, stained with Giemsa or impregnated with silver nitrate, and the measurements were obtained from photomicrographs. In the diseased pacu, the first gill arch was collected and fixed in a 10% buffered formalin solution for histopathological analysis. Parasite specimens from the different collection sites were identified morphologically as C. hexasticha Kiernik (1909). Diseased fish exhibited depigmentation, skin ulceration, scale loss, excessive mucus production and gill lesions. Histopathological analysis of pacu gills displayed epithelial proliferation with mononuclear inflammatory infiltrate, hemorrhages, and scattering necrosis. In Brazilian-farmed fish this is the first record of C. hexasticha, which has great pathogenic potential in cultured freshwater species. In addition, two new hosts are presented. © 2012 Elsevier B.V.