971 resultados para histological subtypes


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Background: The bone tissue responses to Cyanoacrylate have been described in the literature, but none used N-butyl-2-cyanoacrilate (NB-Cn) for bone graft fixation. Purpose: The aims of the study were: (a) to analyze the bone grafts volume maintenance fixed either with NB-Cn or titanium screw; (b) to assess the incorporation of onlay grafts on perforated recipient bed; and (c) the differences of expression level of tartrate-resistant acid phosphatase (TRAP) protein involved in bone resorption. Materials and Methods: Eighteen New Zealand White rabbits were submitted to calvaria onlay grafting on both sides of the mandible. On one side, the graft was fixed with NB-Cn, while on the other hand the bone graft was secured with an osteosynthesis screw. The computed tomography (CT) was performed just after surgery and at animals sacrifice, after 1 (n = 9) and 6 weeks (n = 9), in order to estimate the bone grafts volume along the experiments. Histological sections of the grafted areas were prepared to evaluate the healing of bone grafts and to assess the expression of TRAP protein. Results: The CT scan showed better volume maintenance of bone grafts fixed with NB-Cn (p = 0.05) compared with those fixed with screws, in both experimental times (analysis of variance). The immunohistochemical evaluation showed that the TRAP expression in a 6-week period was significantly higher compared with the 1-week period, without showing significant difference between the groups (Wilcoxon and MannWhitney). Histological analysis revealed that the NB-Cn caused periosteum damage, but provided bone graft stabilization and incorporation similar to the control group. Conclusion: The perforation provided by screw insertion into the graft during fixation may have triggered early revascularization and remodeling to render increased volume loss compared with the experimental group. These results indicate that the NB-Cn possesses equivalent properties to titanium screw to be used as bone fixation material in osteosynthesis.

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Abstract Background To establish the correlation between quantitative analysis based on B-mode ultrasound images of vulnerable carotid plaque and histological examination of the surgically removed plaque, on the basis of a videodensitometric digital texture characterization. Methods Twenty-five patients (18 males, mean age 67 ± 6.9 years) admitted for carotid endarterectomy for extracranial high-grade internal carotid artery stenosis (≥ 70% luminal narrowing) underwent to quantitative ultrasonic tissue characterization of carotid plaque before surgery. A computer software (Carotid Plaque Analysis Software) was developed to perform the videodensitometric analysis. The patients were divided into 2 groups according to symptomatology (group I, 15 symptomatic patients; and group II, 10 patients asymptomatic). Tissue specimens were analysed for lipid, fibromuscular tissue and calcium. Results The first order statistic parameter mean gray level was able to distinguish the groups I and II (p = 0.04). The second order parameter energy also was able to distinguish the groups (p = 0,02). A histological correlation showed a tendency of mean gray level to have progressively greater values from specimens with < 50% to >75% of fibrosis. Conclusion Videodensitometric computer analysis of scan images may be used to identify vulnerable and potentially unstable lipid-rich carotid plaques, which are less echogenic in density than stable or asymptomatic, more densely fibrotic plaques.

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Abstract Background To analyse histological composition and progression of carotid plaque. Methods Thirty-one patients (22 males, mean age 68.03 ± 7.3 years) admitted for carotid endarterectomy for extracranial high-grade internal carotid artery stenosis (≥ 70% luminal narrowing) were enrolled. The patients were divided into 2 groups according to symptomatology (group I, 17 symptomatic patients; and group II, 14 asymptomatic patients). A histological analysis and inflammatory cell quantification of each excised carotid plaque was made. Nine carotid arteries were removed from human cadavers that were not preselected for carotid artery disease. These specimens were used as a control tissue without any macroscopic signs of atherosclerotic plaques. Results Fifty eight percent of all carotid plaques were classified as complex plaque with possible surface defect, hemorrhage or thrombus. The inflammatory cells concentration did not differ between the two groups. All specimens from human cadavers were classified as preatheroma with extracellular lipid pools. Conclusion Asymptomatic and symptomatic patients could have the same histological components on their carotid plaques. Fibrotic and calcific plaques could become vulnerable as complex plaques with surface defect, hemorrhage and thrombus could remain silent. Asymptomatic carotid stenosis should be followed close with no invasive diagnostic methods and clinical evaluation.

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Background: Prostate cancer is a serious public health problem that affects quality of life and has a significant mortality rate. The aim of the present study was to quantify the fractal dimension and Shannon’s entropy in the histological diagnosis of prostate cancer. Methods: Thirty-four patients with prostate cancer aged 50 to 75 years having been submitted to radical prostatectomy participated in the study. Histological slides of normal (N), hyperplastic (H) and tumor (T) areas of the prostate were digitally photographed with three different magnifications (40x, 100x and 400x) and analyzed. The fractal dimension (FD), Shannon’s entropy (SE) and number of cell nuclei (NCN) in these areas were compared. Results: FD analysis demonstrated the following significant differences between groups: T vs. N and H vs. N groups (p < 0.05) at a magnification of 40x; T vs. N (p < 0.01) at 100x and H vs. N (p < 0.01) at 400x. SE analysis revealed the following significant differences groups: T vs. H and T vs. N (p < 0.05) at 100x; and T vs. H and T vs. N (p < 0.001) at 400x. NCN analysis demonstrated the following significant differences between groups: T vs. H and T vs. N (p < 0.05) at 40x; T vs. H and T vs. N (p < 0.0001) at 100x; and T vs. H and T vs. N (p < 0.01) at 400x. Conclusions: The quantification of the FD and SE, together with the number of cell nuclei, has potential clinical applications in the histological diagnosis of prostate cancer.

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Biochemical responses inherent to antioxidant systems as well morphological and anatomical properties of photomorphogenic, hormonal and developmental tomato mutants were investigated. Compared to the non-mutant Micro-Tom (MT), we observed that the malondialdehyde (MDA) content was enhanced in the diageotropica (dgt) and lutescent (l) mutants, whilst the highest levels of hydrogen peroxide (H2O2) were observed in high pigment 1 (hp1) and aurea (au) mutants. The analyses of antioxidant enzymes revealed that all mutants exhibited reduced catalase (CAT) activity when compared to MT. Guaiacol peroxidase (GPOX) was enhanced in both sitiens (sit) and notabilis (not) mutants, whereas in not mutant there was an increase in ascorbate peroxidase (APX). Based on PAGE analysis, the activities of glutathione reductase (GR) isoforms III, IV, V and VI were increased in l leaves, while the activity of superoxide dismutase (SOD) isoform III was reduced in leaves of sit, epi, Never ripe (Nr) and green flesh (gf) mutants. Microscopic analyses revealed that hp1 and au showed an increase in leaf intercellular spaces, whereas sit exhibited a decrease. The au and hp1 mutants also exhibited a decreased in the number of leaf trichomes. The characterization of these mutants is essential for their future use in plant development and ecophysiology studies, such as abiotic and biotic stresses on the oxidative metabolism.

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Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.

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OBJECTIVE: Sickle cell anemia and the interaction S/Beta thalassemia differ in hematological values due to microcytosis and hypochromia caused by the thalassemic mutation. The clinical benefit of long-term hydroxyurea treatment is undeniable in sickle cell disease with monitoring of the biological action of the drug being by the complete blood count. The objective of this work is to compare changes in some of the erythrocytic indexes between S/Beta thalassemia and sickle cell anemia patients on long-term hydroxyurea treatment. METHODS: The values of erythrocyte indexes (mean corpuscular volume and mean corpuscular hemoglobin) were compared in a retrospective study of two groups of patients (Sickle cell anemia and S/Beta thalassemia) on hydroxyurea treatment over a mean of six years. RESULTS: The quantitative values of the two parameters differed between the groups. Increases in mean corpuscular volume and reductions in mean corpuscular hemoglobin delay longer in S/Beta thalassemia patients (p-value = 0.018). CONCLUSION: Hematological changes are some of the beneficial effects of hydroxyurea in sickle cell disease as cellular hydration increases and the hemoglobin S concentration is reduced. The complete blood count is the best test to monitor changes, but the interpretation of the results in S/Beta thalassemia should be different.

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Reactivity and titers of autoantibodies vary during the course of autoimmune hepatitis (AIH), and some autoantibodies have been associated with disease activity and adverse outcomes after treatment. The aim of this study was to assess the autoantibody behavior in AIH and its significance as predictors of biochemical and histological remission. A total of 117 patients with AIH (mean age 18.6 [4-69] years) were evaluated and tested for auto- antibodies at disease onset and successively (mean 3.2 [2-6] times) after a mean follow-up evaluation of 70 [20-185] months. Antismooth muscle (ASMA), antiliver kidney micro- some type 1 (anti-LKM1), antiliver cytosol type 1 (anti-LC1), antimitochondrial, antinu- clear (ANA), and antiactin antibodies (AAA) were determined at disease onset and 379 other times during the follow-up evaluation through indirect immunofluorescence in rodent tissues, HEp-2 cells, and human fibroblasts. Anti-SLA/LP were assessed 45 times in the follow-up evaluation of 19 patients using enzyme-linked immunosorbent assay (ELISA). Upon admission, AIH types 1 and 2 were observed in 95 and 17 patients, respectively. Five subjects had AIH with anti-SLA/LP as the sole markers. Patients initially negative for AAA did not develop these antibodies thereafter. ANA were detected de novo in six and three subjects with AIH types 1 and 2, respectively. After treatment, only ASMA ( > 1:80) and AAA ( > 1:40) were significantly associated with biochemical (76.9% and 79.8%) and histological features (100% and 100%) of disease activity ( P < 0.001). Conclusion: With the exception of ANA, the autoantibody profile does not markedly vary in the course of AIH. The persistence of high titers of ASMA and/or AAA in patients with AIH is associated with disease activity.

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[EN]The present study provides a description of the morphological, histological and histochemical development, and the ecological implications of red porgy larvae reared in mesocosm, from hatching to 30 days after hatching (DAH).

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Für diese Arbeit wurden sechs neue Benzodiazepinderivate, TC07, TC08, TC09, TC10, TC11 und TC12, hergestellt. Diese wurden mittels Radioligandenbindungsassay sowohl auf ihre Bindungseigenschaften für Membranen des Cerebellum, des Hippo-campus und des Cortex der Ratte hin untersucht, als auch für Membranen von HEK293 Zellen, die transient rekombinante GABAA Rezeptoren exprimierten. Zusätz-lich wurden kompetitive in situ Rezeptorautoradiographien an Rattenhirnschnitten mit den Liganden [3H]Ro15-4513 und [3H]R015-1788 durchgeführt. Zusammen ergaben sich aus diesen Experimenten deutliche Hinweise auf eine Selektivität der Verbindun-gen TC07, TC11 und TC12 für a5-Untereinheiten enthaltende GABAA Rezeptoren mit a5-Affinitäten im niedrigen nanomolaren Bereich. In vivo Bindungsexperimente in Ratten, mit [3H]Ro15-1788 als Tracer und TC07 als Kompetitor, ergaben, dass TC07 mehr [3H]Ro15-1788 im Vorderhirn als im Cerebellum verdrängt. Bezog man die regionale Verteilung der a5-Untereinheit des GABAA Rezep-tors im Rattenhirn mit ein – sehr wenige a5-Untereinheiten im Cerebellum, etwa 20 % der GABAA Rezeptor-Untereinheiten im Hippocampus – untermauerten diese Ergeb-nisse die Vermutung, TC07 könne a5-selektiv sein. Diese Daten bestätigten darü-berhinaus, dass TC07 die Blut-Hirn-Schranke passieren kann. Für elektrophysiologische Messungen mit TC07 und TC12 wurden die oben erwähnten transient transfizierten HEK293 Zellen verwendet, welche die GABAA Rezeptor Unte-reinheitenkombination a5b3g2 exprimierten. Das Dosis-Antwort Verhalten ergab keinen signifikanten Effekt für TC12. Die Daten von TC07 dagegen lassen auf einen schwach negativ modulatorischen Effekt schließen, was, zumindest theoretisch, die Möglichkeit eröffnet, TC07 auch als sogenannten cognitive enhancer einzusetzen. Der errechnete Ki-Wert lag in derselben Größenordnung wie der Ki-Wert, der anhand der Bindungsas-saydaten errechnet wurde. Insgesamt rechtfertigen die bisherigen Ergebnisse die radiochemische Markierung mit 18F von drei der sechs getesteten Verbindungen in der Reihenfolge TC07, TC12 und TC11. Des Weiteren wurde [18F]MHMZ, ein potentiell 5-HT2A selektiver Ligand und PET-Tracer einschließlich Vorläufer und Referenzverbindungen, mit hohen Ausbeuten syn-thetisiert (Herth, Debus et al. 2008). Autoradiographieexperimente mit Rattenhirn-schnitten zeigten hervorragende in situ Bindungseigenschaften der neuen Verbindung. Die Daten wiesen eine hohe Selektivität für 5-HT2A Rezeptoren in Verbindung mit einer niedrigen unspezifischen Bindung auf. [18F]MHMZ erfährt in vivo eine schnelle Metabo-lisierung, wobei ein polarer aktiver Metabolit entsteht, welcher vermutlich nicht die Blut-Hirn-Schranke passieren kann. Transversale, sagittale und coronale Kleintier-PET-Bilder des Rattenhirns zeigten eine hohe Anreicherung im frontalen Cortex und im Striatum, während im Cerebellum so gut wie keine Anreicherung festzustellen war. Diese Verteilung deckt sich mit der bekann-ten Verteilung der 5-HT2A Rezeptoren. Die in vivo Anreicherung scheint sich ebenfalls gut mit der Verteilung der in den Autoradiographieexperimenten gemessenen Bindung zu decken. Nach Berechnungen mit dem 4-Parameter Referenzgewebe Modell beträgt das Bindungspotential (BP) für den frontalen Cortex 1,45. Das Cortex zu Cerebellum Verhältnis wurde auf 2,7 nach 30 Minuten Messzeit bestimmt, was bemerkenswert nah an den von Lundkvist et al. für [11C]MDL 100907 publizierten Daten liegt. Abgesehen von der etwas niedrigeren Affinität waren die gemessenen in vitro, in situ und in vivo Daten denen von [3H]MDL 100907 und [11C]MDL 100907 sehr ähnlich, so dass wir ein [18F]Analogon in der Hand haben, das die bessere Selektivität von MDL 100907 verglichen mit Altanserin mit der längeren Halbwertszeit und den besse-ren Eigenschaften für die klinische Routine von 18F verglichen mit 11C verbindet. Die Ergebnisse von [18F]MHMZ rechtfertigenden weitere Experimente, um diesen Liganden für die klinische Routine am Menschen nutzbar zu machen.

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Platelet rich plasma (PRP) has been proposed to be a useful adjunct to bone grafting.

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The aim of the present study is to evaluate the clinical and histologic healing of deep intrabony defects treated with guided tissue regeneration (GTR) with a collagen membrane from bovine pericardium and implantation of granular bovine bone biomaterial.