18 resultados para High-grade metamorphic complexes

em Universidade Federal do Rio Grande do Norte(UFRN)


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This thesis aims to advance in the geological knowledge of the region comprising the Piancó-Alto Brígida (TPAB) and Alto pajeú (TAP) terranes, in the Transversal Zone Domain (Borborema Province, NE Brazil), with the main objective of understanding the geodynamic evolution and the structural framework of these units. To reach this objective, and besides field work and interpretation of traditional aerial photographs, other tools were employed like of remote sensing products (Landsat 7 ETM+, aeroradiometrics, aeromagnetics and topographical images), lithogeochemical (whole rock) analyses and geochronological dating (U-Pb in zircon), besides integration with literature data. In the area, several precambrian geological units outcrop, represented in the TAP by the paleoproterozoic Serra Talhada and Afogados da Ingazeira complexes, Riacho Gravatá Complex (metavolcano-sedimentary sequence of Stenian-Tonian age) and Cariris Velhos orthogneisses (of Tonian age). The TPAB comprises the Santana do Garrote (lower unit) and Serra do Olho d'Água (upper unit) formations of the Cachoeirinha Group (Neoproterozoic III), besides the Piancó orthogneisses and Bom Jesus paragneisses; the latter correspond to an older (basement ?) block and a possible high grade equivalent of the Cachoeirinha Group (or Seridó Group ?), respectively. Several Brasiliano-age plutons occur in both terranes.The aeromagnetic data show the continuity, at depth, of the main shear zones mapped in the region. The Patos, Pernambuco, Boqueirão dos Cochos, Serra do Caboclo, Afogados da Ingazeira/Jabitacá and Congo-Cruzeiro do Nordeste shear zones reach depths greater than to 6-16 km. The aeromagnetic signature of other shear zones, like the Juru one, suggests that these structures correspond to shallower crustal features. The satellite images (Landsat 7 ETM+) and aerogamaspectrometric images discriminate different geological units, contributing to the mapping of the structural framework of the region. The Serra do Caboclo Shear Zone was characterized as the boundary/suture between the TPAB and TAP. This structure is an outstanding, pervasive feature that separates contrasting geological units, such as the Neoproterozoic III Cachoeirinha Group in the TPAB and the Riacho Gravatá Complex and the Cariris Velhos metaplutonics, of Stenian-Tonian age, in the TAP. Occupying different blocks, these units are not found in authoctonous relations, like unconformities and intrusive contacts. Concerning the Cariris Velhos (ca. 1,0 Ga old) event is recorded by radiometric ages of the Riacho Gravatá Complex metavolcanics and intrusive augen and orthogneisses, all of them displaying geochemical affinities of arc or collisional settings. A structural signature of this event was not recorded in the region, possibly due to its low grade/low strain style, obliterated by the overprinting of younger, higher grade/high strain Brasiliano-age fabrics.The first tectonic event (D1) observed in the Cariris Velhos lithotypes presents contractional kinematics with transport to the NW. Neoproterozoic III geochronologic dates, obtained in late-D1 granitoids, imply a Brasiliano age (ca. 610-600 Ma) for this deformation event. The second tectonic event (D2) characterized in the region corresponds to the Brasiliano transcurrent kinematics of the outstanding shear zones and associated granitoid plutons. The geochronological (U-Pb in zircon) data obtained during this thesis also confirms the occurrence of the Cariris Velhos magmatic suite in the TAP, as well as the Neoproterozoic III age to the Cachoeirinha Group in the TPAB. The TAP (Riacho Gravatá Complex, augen and orthogneisses) is interpreted as a continental arc possibly accreted to a microcontinent during the Cariris Velhos (Stenian-Tonian) event. Later on, this terrane collided with the TPAB at the beginning of the Brasiliano orogeny (D1 contractional deformation), and both domins were reworked by the transcurrent shear deformation of the D2 event

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The studied area is geologically located in the Northern Domain of the Borborema Province (Northeast Brazil), limited to the south by the Patos shear zone. Terranes of the Jaguaribeano system are dominant, flanked by the Piranhas (E and S sides) and Central Ceará (NE side) terranes. Its basement comprises gneiss -migmatite terrains of Paleoproterozoic to Archean age (2.6 to 1.9 Ga old), overprinted by neoproterozoic to cambrian tectonotherma l events. Narrow supracrustal belts ( schist belts) display a 1.6 to 1.8 Ga age, as shown by whole - rock Rb-Sr and zircon U-Pb and Pb/Pb dates in acid metavolcanics which dominate in the lower section of these sequences, and in coeval metaplutonics (granitic augen gneisses). From the stratigraphic point of view, three Staterian belts are recognized: 1. Orós Belt - made up by the Orós Group, subdivided in the Santarém (predominantly pure to impure quartzites, micaschists and metacarbonates) and Campo Alegre (metandesites, metabasalts, metarhyolites and metarhyodacites, interlayered with metatuffs and metasediments) formations, and by the Serra do Deserto Magmatic Suite (granitic augen gneisses). 2. Jaguaribe Belt - its lithostratigrahic-lithodemic framework is similar to the one of the Orós Belt, however with a greater expression of the volcano -plutonic components (Campo Alegre Formation and Serra do Deserto Magmatic Suite). The Peixe Gordo Sequence, separately described, is also related to this belt and contain s metasedimentary, metavolcanic (with subordinated volcanoclastics) and metaplutonic units. The first one correlated to the Orós Group and the latter the Serra do Deserto Magmatic Suite. 3. Western Potiguar Belt - represented by the Serra de São José Gro up, subdivided in the Catolezinho (biotite -amphibole gneisses with intercalations of metacarbonates, calcsilicate rocks, amphibolites and quartzite beds to the top) and Minhuins (quartzites, micaschists, metaconglomerates, calcsilicate rocks, acid to the b asic metavolcanics and metatuffs) formations. Its late Paleoproterozoic (Staterian) age was established by a Pb/Pb date on zircons from a granitic orthogneiss of the Catolezinho Formation. The petrographic characteristics and sedimentary structures of the Santarém Formation of the Orós Group point to deltaic to shallow marine depositional systems, overlain by deep water deposits (turbidites). The geodynamic setting of this region encompassed a large depositional basin, probably extending to the east of the Portalegre shear zone and west of the Senador Pompeu shear zone, with possible equivalents in the Jucurutu Formation of the Seridó Belt and in the Ceará Group of central Ceará. The Arneiróz Belt, west Ceará, displays some stratigraphic features and granito ids geochemically akin to the ones of the Orós Belt. The evolutionary setting started with an extensional phase which was more active in the eastern part of this domain (Western Potiguar and part of the Jaguaribe belts), where the rudite and psamite sedime ntation relates to a fluviatile rift environment which evolved to a prograding deltaic system to the west (Orós Group). The basaltic andesitic and rhyolitic volcanics were associated to this extensional phase. During this magmatic event, acid magmas also crystallized at plutonic depths. The Orós Group illustrates the environmental conditions in the western part of this domain. Later on, after a large time gap (1.6 to 1.1 Ga), the region was subjected to an extensional deformational episode marked by 900 Ma old (Sm-Nd data) basic rocks, possibly in connection with the deposition of the Cachoeirinha Group south of the Patos shear zone. In the 800 to 500 Ma age interval, the region was affected by important deformational and metamorphic events coupled with in trusion of granitic rocks of variable size (dykes to batholiths), related to the Brasiliano/Pan -African geotectonic cycle. These events produced structural blocks which differentiate, one from the other, according to the importance of anatectic mobilizatio n, proportion of high-grade supracrustals and the amount of neoproterozoic -cambrian granitoid intrusions. On this basis, a large portion of the Jaguaretama Block/Terrane is relatively well preserved from this late overprint. The border belts of the Jagua retama Block (Western Potiguar and Arneiroz) display kyanite-bearing (medium pressure) mineral associations, while in the inner part of the block there is a north-south metamorphic zoning marked by staurolite or sillimanite peak metamorphic conditions. Regarding the deformations of the Staterian supracrustal rocks, second and third phases were the most important, diagnosed as having developed in a progressive tectonic process. In the general, more vigorous conditions of PT are related to the interval tardi - phase 2 early-phase 3, whose radiometric ages and regional structuring indicators places it in the Brasiliano/Pan-African Cycle. In the Staterian geodynamic setting of Brazilian Platform , these sequences are correlated to the lower Espinhaço Supergroup (p.ex., Rio dos Remédios and Paraguaçu groups, a paleproterozoic rift system in the São Francisco Craton), the Araí and Serra da Mesa groups (north of Goiás, in the so -called Goiás Central Massif), and the Uatumã Group (in the Amazonian Craton). Granitic ( augen gneisses) plutonics are also known from these areas, as for example the A-type granites intrusive in the Araí and Serra da Mesa groups, dated at 1.77 Ga. Gravimetric and geological data place the limits of the Jaguaribeano System (terranes) along the Senador Pompeu Shear Zone (western border) and the Portalegre- Farias Brito shear zone (eastern and southern). However, the same data area not conclusive as regards the interpretation of those structures as suture of the terrane docking process. The main features of those shear zones and of involved lothological associations, appear to favour an intracontinental transpressional -transcurrent regime, during Neoproterozoic-Cambrian times, marking discontinuities along which different crustal blocks were laterally dispersed. Inside of this orogenic system and according to the magnetic data (total field map), the most important terrane boundary appears to be the Jaguaribe shear zone. The geochronological data, on some tectonostratigraphic associations (partly represented by the Ceará and Jucurutu groups), still at a preliminary level, besides the lack of granitic zonation and other petrotectonic criteria, do not allow to propose tectonic terrane assembly diagrams for the studied area

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A quantitative, descriptive, cross-sectional and retrospective study, using technical procedures of document consultation from secondary sources and health household survey with application form for face to face inter views, with the assent nº.039/2011 from the Ethics Committee of the Federal University of Rio Grande do Norte. The aim of this study was to analyze the cervix cancer control in the area47 of the Health Family Centre Nova Natal II. The cancer cervix is the second most common cancer among women worldwide. In Brazil screening for early detection and treatment of disease has been poorly done and follow-up to reduce mortality has not been executed. From a total of1170women belonging to area 47, who under went screening by the Pap test in the period from 2005 to 2010,was elected a sample of 38 women with positive cervical changes, over 18 years old. The calculation of frequency analysis of socio demographic and clinical and epidemiological selected variables with the results of cervical changes, using the X2 test and taking as significance level of p<0.05 was not statistically significant. The predominant age range was 25 to 64 years (68.9%), most no white women (60.5%), predominantly with primary education (57.9%), most married (68.4%) and housewives (68.4%) with early age of sexual activity (86.8%), the minority smokers (13.2%), with a sexual partner (36.8%). At the time of interview, 42.1% of the women voiced complaint of discharge, while only 2.6% reported bleeding. In relation to the occurrence of STDs (including HPV), 10.5% of women reported being a carrier. The use of oral contraceptives was 32.3% of women, from 2 to 4 years (44.4%). The result of the last screening test performed, showed prevalence of immature squamous metaplasia (55.3%), followed by intraepithelial low- grade lesion (including the cytopathologic HPV effect and cervical intra epithelial neoplasia grade I) (31.6%); intraepithelial high-grade lesion (including cervical intraepithelial neoplasia grade II and III) (7.9%), atypical squamous non neoplastic cells (5.3%). There was no squamous cell carcinoma and adenocarcinoma. Most women received information about the action that should be done after the last screening test result (55.3%), but how to perform follow, most women did not report having done so (55.3%). The follow-up group of women studied, with varying degrees of cervical abnormalities, should only be completed with the discharge by cure, established inconsecutive negative cytology, a goal that is not being achieved in the area 47 of the Health Family Centre of Nova Natal II

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Currently, bone morphogenetic proteins (BMPs) have effective participation in the growth of malignancies. Knowing that there are few studies involving BMPs and oral squamous cell carcinoma, this work constitutes an immunohistochemical study of BMP-2, BMPR IA and BMPR II in squamous cell carcinomas (SCC) of the lower lip relating to the clinical and pathological aspects of this lesion. The sample consisted of 40 cases of SCC of the lower lip, being 20 cases of SCC of the lower lip with regional metastasis and 20 cases without metastasis. We evaluated the intensity of expression (score 1 to mark absent / weak, score 2 for high ) and was found the percentage of labeled cells, where the score was 1 cases with 0 to 50% of positive cells, score 2 with 51 to 75% of positive cells, and score 3 more than 75% of positive cells. The sample comprised 72.5% of men with a mean age of 65.8 years, there was a predominance of stage II and 52.5% of the carcinomas were classified as low grade, being carcinoma with metastasis presenting most cases (70%) as carcinomas of high malignancy grade (p = 0.004). The largest number of cases of SCC of the lower lip that were in stages I / II (61, 9%) were classified as carcinomas of low grade malignancy and carcinomas in stages III / IV were classified as high-grade tumors (p = 0, 024). The BMP-2 showed strong intensity of immunostaining in 82.5%, BMPR-IA showed 55% of cases with an intensity of immunostaining absent / weak and BMPR-II showed 85% of cases with an intensity of immunostaining absent / weak. Only the protein BMPR-IA were significantly associated with all clinic-pathological parameters studied, metastasis (p <0.001), TNM (p <0.001) and histological grade of malignancy with (p = 0.028). The percentage of positive cells, all markers showed the highest number of cases with more than 75% of positive cells (score 3) and only BMPR-II showed statistical difference when related to the presence and absence of metastasis (p = 0.049 ). We conclude that there is disturbance in the BMP signaling pathway in EC-mediated lower lip and that high expression of BMP-2 associated with the expression of BMPR-IA and BMPR-II are associated with metastasis in carcinoma

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The presence of inflammatory cells within the tumor microenvironment plays a dual role that may contribute both to the progression and for inhibition of tumor growth. Recent studies suggest that the quality, not the quantity, of the inflammatory infiltrate is the most important determinant for prognosis. Therefore, TCD8 cells and natural killer cells are the main effector cells in combating cancer. The aim of this study was to assess, through the immunohistochemical study, the expression of TCD8 lymphocytes and NK cells in epidermoid carcinoma (EC) of the lower lip. The sample consisted of 32 specimens of EC of the lower lip, of which 16 had regional lymph node metastasis, and the 16 remaining, free of metastases. The total number of positive cells at the front of invasion were evaluated quantitatively and the results were related to clinical TNM staging, histological grade of malignancy and prognostic factors. It was observed for the group with metastasis, prevalence of stages III and IV (p<0.0001). Most patients with metastasis, had a high grade of malignancy (p=0.006). Most cases classified as high grade of malignancy had stages III and IV (p=0.032). Of the total sample, there were three cases of recurrence and five with death, however these variables were not statistically significant when associated with clinicopathological parameters. The immunostaining of CD8 and CD57, respectively, showed no statistically significant association with any of the clinicopathological parameters studied, metastasis (p=0.346, p=0.622), TNM classification (p=0.146, p=0.576), histological grade of malignancy (p=0.936, p=936), recurrence (p=0.075, p=0.075) and death (p=0.897, p=0.856). Believing in the function of the immunological system against malignant cells, it is concluded that the TD8 lymphocytes and NK cells, would be acting in the control of the progression of malignant neoplasms, but not in isolated manner

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Bone morphogenetic proteins (BMPs) are cytokines involved in proliferation and angiogenesis of many kind of human cancer. The present study analyzed the immunohistochemical expression of BMP-2, BMPR-II, BMPR-IA and endoglin (CD105) and their relationship with the biological behavior and local angiogenesis in tongue oral squamous cells carcinoma (SCC). The sample consisted of 25 cases of tongue SCC without metastasis, 25 tongue SCC with metastasis and 25 cases of Inflamatory Fibrous Hyperplasia (IFH).The histological grade of malignancy proposed by Bryne (1998), adapted by Miranda (2002) was used to classify all tongue SCC cases. Score 0 was attributed to absent-weak immunoexpression and score 1 for strong immunostaning and pattern of distribution was focal or diffuse. Microvessel counts (MVC) was established for CD105. Most of the patients with tongue SCC was male. The principal age in tongue SCC without metastasis was over 65 years and in tongue SCC with metastasis was between 45-65 years. There were predominance of stage II in TNM and in the specimens with high-grade, independent of studied group. For BMP-2, 56% of tongue SCC without metastasis and 72% tongue SCC with metastasis exhibited score 1 while the IFH showed secore 0 in 72% of the cases, with statistical association (p=0,007). Considering the BMPR-II, 52% of tongue SCC without metastasis exhibited score 0; 56% tongue SCC with metastasis and 60% IFH showed score 1. The majority cases of BMPR-IA demonstrated score 1 and 100% of CD105 exhibited strong immunoexpression in tongue SCC. Regarding the pattern distribution, it was noted a tendency to diffuse pattern for the proteins in all groups. The means of MVC were similar in tongue SCC without metastasis (32,91) and in tongue SCC with metastasis (32,05), however existed statistical difference with IFH (p<0,001). There was statistical association of BMP-2 expression with BMPR-II (p=0,008), BMPR-IA (p=0,006) and CD105 (p=0,046). An association between TNM and BMP-2 immunoexpression and their receptors was not detected, nevertheless this association was found with MVC (p=0,047) whose averages were higher for the stages II (35,97) e IV (35,69). No association between histological grading and these proteins was observed. This study suggests that the superexpression of BMP-2 signaling pathways acts on cell proliferation in tongue SCC and can be implicated with more invasive potential. Additionaly, the CD105 is a potent biological marker of neovascularization in this neoplasm and their association with BMP-2 and BMPR-IA receptor, showed that this type of cancer in BMP-2 is presented as pro-angiogenic in the metastatic process

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The tumor hypoxia modulates a series of genetic changes related to adaptive development, invasion and metastasis of various human cancers, among which squamous cell carcinoma of the tongue (SCCT). The objective of this study was to analyze clinical, morphological and immunohistochemical expression by HIF-1α, GLUT-1 and CA-IX in 57 cases of CEL and correlated this expression to clinical parameters and morphological. After a descriptive analysis of data on gender, age, race, and habits of patients, it was found that the results were consistent with the literature. The clinical and morphological parameters analyzed and the expression of these markers of hypoxia were subjected to statistical analysis (Qui2 test), verifying that they can be used as indicators of the biological behavior of CEL. Among the results of this study, we observed that the intensity of expression for HIF-1α, in most cases located in the cytoplasm and nucleus, statistically correlated with clinical staging (p = 0.011) and histological grading (p = 0.002). As for the relationship between the distribution of labeling for HIF-1α and metastasis, the chi-square (Qui2) showed that there was statistically significant differences between the groups (p = 0.040). 75.8% of the sample who had metastases, there was the predominance of diffuse marking. The immunoexpression cytoplasmic/membrane GLUT-1 showed a statistically significant correlation with the clinical stage (p = 0.002) and histological grading (p = 0.000). Concerning the location of markings for GLUT-1 tumor on the island, there was a predominance of peripheral marking specimens in most low-grade (78.6%). In the sample of high-grade, prevailed the location center/periphery (55.8%). According to the chi-square (Qui2), the location on the island of the tumor (p = 0.025) showed statistically significant difference in histological grading. The immunoreactivity of CA-IX, in most cases located in the membrane and cytoplasm, exhibited a statistically significant correlation with histological grading (p = 0.005). Based on these results, we can conclude a broad participation of these markers of hypoxia in oral carcinogenesis and its possible use as markers of biological behavior and tumor progression in CEL

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Oral squamous cell carcinoma (OSCC) is an important cause of morbidity and mortality worldwide despite recent advances in treatment. There are several studies aiming to find markers that may improve the assessment of this disease prognosis. Studies about genetic polymorphisms have gained prominence due to their influence on individual susceptibility to cancer development. The aim of this study was to evaluate the association between the frequency of polymorphisms XPD Lys751Gln and XRCC3 Thr241Met and clinicopathological features of OSCC cases, including age, sex, presence or absence of metastases, and histological grading of malignancy according to Bryne (1998). Sample consisted of 54 cases of OSCC and 40 cases of inflammatory fibrous hyperplasia (IFH). OSCC cases were classified as low or high grade. DNA samples were previously extracted from paraffin blocks. Genotypes for each case were determined through PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism). Results were analyzed by Fisher s exact test and Chi-square test and the odds ratio was calculated considering p < 0.05 to indicate statistical significance. For XPD, Lys/Gln genotype was more common in IFHs (n=28; 70%) than in OSCCs (n=24; 44.4%) (OR: 0.3; p<0.05). Frequency of Gln allele was higher in high-grade lesions when compared to low grade lesions (0.48 and 0.21, respectively) (OR: 3.4; p<0.05). For XRCC3, Met allele was more common in OSCC than in IFH (0.49 and 0.35, respectively) (OR: 2.6; p<0.05). Met/Met genotype was associated with presence of metastases (OR: 8.1; p<0.05). There was no statistically significant association between the genotypes and the age or sex of patients. In the present sample, the higher frequency of XPD Gln allele in IFH reveals a possible protective role of this variant against the development of OSCC. However, its association with high-grade lesions indicates that this allele could influence the tumor progression after the neoplasia development. The presence of XRCC3 Met allele, in turn, seems to contribute to the development of OSCC and metastases

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This dissertation describes the igneous suites of the Japi granitoid pluton, intrusive in the Paleoproterozoic gneiss-migmatite complex of the eastern domain of the Seridó Belt, northeastern Brazil. Field relations show that the pluton is affected by strong deformation associated to the Brasiliano orogeny (known as the D3 phase) , with a NW-trending extensionalleft-hand senestral shear zone (the Japi Shear Zone, JSZ) bordering the intrusive body to the west. Four plutonic suites are found in the main pluton and as satellyte intrusions, besides Iate pegmatite and pink leucogranites. An alkaline granitoid suite, dominated by syenogranites bearing sodic augite (and subordinate hornblende), define a main elliptical intrusion. In its northern part, this intrusion is made up by concentric sheets, contrasting with a smaller rounded stock to the south. These granites display a pervasive solid-state S>L fabric developed under high T conditions, characterized by plastic deformation of quartz and feldspar. It is especially, developed along the border of the pluton, with inward dips. A regular magmatic layering is present sometimes, parallel to the tectonic foliation. The syntectonic emplacement as regards to the Brasiliano (D3) event is indicated by the common occurrence of dykes and sheets along transtensional or extensional sites of the major structure. Field relations attest to the early emplacement of the alkaline granites as regards to the other suites. A basic-to-intermediate suite occurs as a western satellyte body and occupying the southern tail of the main alkaline pluton. It comprises a wide variety of compositional terms, including primitive gabbros and gabbro-norites, differentiated to monzonitic intermediate facies containing amphibole and biotite as their main mafic phases. These rocks display transitional high-K calc-alkaline to shoshonitic affinities. Porphyritic monzogranite suítes commonly occur as dykes and minor intrusives, isolated or associated with the basic-tointermediate rocks. In the latter case, magma mingling and mixing features attest that these are contemporaneous igneous suites. These granites show K-feldspar phenocrysts and a hornblende+biotite+titanite assemblage, displaying subalkaline/monzonitic geochemical affinities. Both suites exhibit SL magmatic fabrics overprinting or transitional to solid-state D3 deformation related to the JSI. Chemical data clearly show that they are related to different parental magmas. Finally, a microgranite suite occurs along a few topographic ridges paralell to the JSI. It comprises dominantly granodiorites with a mineralogy similar to the one of the porphyritic granitoids. However, discriminant diagrams show their distinct calc-alkaline affinity. The granodiorites display an essencially magmatic fabric, even though an incipient D3 solid-state structure may be developed along the JSI. Intrusion relationships with the previous suites, as well as regards to the D3 structures, point to their Iate emplacement. All these suites are intrusive in a Paleoproterozoic, high-grade gneiss-migmatite complex affected by two previous deformation phases (D1, D2). The fabrics associated with these earlier events are folded and overprinted by the younger D3 structures along the JSZ. The younger deformation is characterized by NE-dipping foliations and N/NE-plunging stretching lineations. In the JSZ northern termination the foliation acquires an ENE orientation, containing a stretching lineation plunging to the south. Symmetric kinematic cri teria developed at this site confirms the transpressional termination of the JSZ, as also shown by orthorrombic quartz c-axis patterns. E-W-trending d extra I shear zones developed in the central part of the JSZ are interpreted as antithetic structures associated to the transtensional deformation along the JSZ. This is consistent with its extensional-transcurrent kinematics and a flat-and-ramp geometry at depth, as shown by gravimetric data. The lateral displacement of the negative residual Bouguer anomalies, as regards to the main outcropping alkaline pluton, may be modelized by other deeper-seated granite bodies. Based on numerical modelling it was possible to infer two distinct intrusion styles for the alkaline pluton. The calculated model values are consistent with an emplacement by sheeting for the northern body, as already suggested by satellyte imagery and field mapping. On the other hand, the results point to a transition towards a diapir-related style associated to the smaller. southern stock. This difference in intrusion styles may relate to intensity variations and transtensional sites of the shear deformation along the JSZ. Trace element and Sr and Nd isotopes of the alkaline granites are compatible with their derivation trom a more basic crustal source, as compared to the presently outcropping highgrade gneisses, with participation (or alternatively dominated by) of an enriched lithospheric mantle component. Like other igneous suites in the Seridó Belt, the high LlL contents and fractionated REE patterns of the basic rocks also point to an enriched mantle as the source for this kind of magmatism. Geochemical and isotope data are compatible with a lower crustal origin for the porphyritic granites. On the basis of the strong control of the JSZ on the emplacement of lower crustal (porphyritic and alkaline granites) or lithospheric mantle (basic rocks, alkaline granites or a component of them) magmas, one may infer a deep root for this structure, bearing an important role in magma extraction, transport and emplacement in the Japi region, eastern domain of the Seridó Belt

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Oral tongue squamous cell carcinoma (OTSCC) has an aggressive biological behavior, with a high propensity for the development of lymph node metastases. In this context, lymphangiogenesis is considered an important phenomenon for the spread of tumor cells and may be influenced by microenvironmental stimuli. Mast cells have been implicated in tumor progression, although their influence in the formation of lymphatic vessels is not well established. The aim of this study was to analyze, in a case series of OTSCC (n=50), possible correlations between lymphatic vessel density (LVD), mast cell count and clinicopathological features, including tumor-node-metastasis (TNM) stage, histological grade of malignancy (Bryne, 1998), and nodal metastasis. LVD was established as the mean number of lymphatic vessels immunostained by anti-podoplanin (D2-40) antibody, identified in five microscopic fields (200x). For the analysis of mast cells, tryptase-immunoreactive cells were quantified in five fields (400x). Both immunostainings were analyzed in the tumor center and invasion front. Intratumoral lymphatic density (ILD) was higher in cases in advanced clinical stages (III-IV), compared to those in initial stages (I-II), as well as in metastatic cases in respect of non-metastatic (p<0,05). There were no statistically significant differences between low-grade and high-grade malignancy cases with respect to ILD (p>0,05). Peritumoral lymphatic density (PLD) and mast cell counts showed no significant relations with any of the clinicopathological parameters evaluated (p>0,05). Also there were no significant correlations between LVD and mast cell counts, whether in intratumoral (r = -0,004; p=0,977) or peritumoral region (r = -0,154; p=0,285). The results of the present study suggest that intratumoral lymphatic vessels may contribute in part to the progression of OTSCC, although PLD may be insufficient to justify differences in biological behavior. This supports the hypothesis of involvement of other mechanisms in metastatic spread of malignant cells, which could complement the effects of lymphangiogenesis. Although mast cells perform several pro- and antitumoral functions, they do not appear to directly influence aggressiveness of OTSCC. In addition, the quantity of these cells may not be essential for lymphatic vessel formation.

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Squamous cell carcinoma of oral tongue shows high rates of morbidity and mortality in the population, therefore, great efforts are being made to classify morphological changes and identify biomarkers that have prognostic value and that are able to group patients in individualized therapeutic options. From this perspective, there is the heat shock factor 1 (HSF1), which is a heat shock factor transcription protein (HSPs) that allows the cancer to deal with stressors associated with malignancy, acting differently in tumor progression. This research aimed to perform a clinico-pathological analysis of 70 cases of oral tongue squamous cell carcinoma (OTSCC) and immunohistochemical study of the expression of HSF1 protein in OTSCC, comparing it with 30 specimens of normal oral mucosa (NOM), and correlating this immunostaining with clinico-pathological aspects of OTSCC. To analyze the association between immunoexpression of HSF1 and clinicophatoloical aspects, the cases were categorized in minor and major overexpression, based in the median immunostaining score. Regarding the cases of OTSCC, 57.1% showed clinical stage III or IV, 82.9% were graded as high grade according to Bryne (1998) and 47.1% as high risk of malignancy according to Brandwein-Gensler et al., (2005). A disease free survival rate of 47.84% and overall survival rate of 68.20% was observed in the analyzed cases, and the high degree of malignancy according to Bryne’s system (1998) (p=0.05), tumor size T3 or T4 (p=0.04), local recurrence (p=0.02), and perineural invasion (p=0.02) determined negative impacts in survival time. We observed also a statistically significant result (p<0.01) when comparing the immunoreactivity of HSF1 between NOM and OTSCC. This significantly increased expression of HSF1 in cases of OTSCC suggests that this protein acts, indeed, in the pathogenesis of this disease. However, there were no statistically significant associations between this overexpression and the clinico-pathological parameters analyzed. This finding may reflect the influence of epigenetic events on HSF1 gene or a possible stability of this protein expression throughout disease progression.

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Squamous cell carcinoma of oral tongue shows high rates of morbidity and mortality in the population, therefore, great efforts are being made to classify morphological changes and identify biomarkers that have prognostic value and that are able to group patients in individualized therapeutic options. From this perspective, there is the heat shock factor 1 (HSF1), which is a heat shock factor transcription protein (HSPs) that allows the cancer to deal with stressors associated with malignancy, acting differently in tumor progression. This research aimed to perform a clinico-pathological analysis of 70 cases of oral tongue squamous cell carcinoma (OTSCC) and immunohistochemical study of the expression of HSF1 protein in OTSCC, comparing it with 30 specimens of normal oral mucosa (NOM), and correlating this immunostaining with clinico-pathological aspects of OTSCC. To analyze the association between immunoexpression of HSF1 and clinicophatoloical aspects, the cases were categorized in minor and major overexpression, based in the median immunostaining score. Regarding the cases of OTSCC, 57.1% showed clinical stage III or IV, 82.9% were graded as high grade according to Bryne (1998) and 47.1% as high risk of malignancy according to Brandwein-Gensler et al., (2005). A disease free survival rate of 47.84% and overall survival rate of 68.20% was observed in the analyzed cases, and the high degree of malignancy according to Bryne’s system (1998) (p=0.05), tumor size T3 or T4 (p=0.04), local recurrence (p=0.02), and perineural invasion (p=0.02) determined negative impacts in survival time. We observed also a statistically significant result (p<0.01) when comparing the immunoreactivity of HSF1 between NOM and OTSCC. This significantly increased expression of HSF1 in cases of OTSCC suggests that this protein acts, indeed, in the pathogenesis of this disease. However, there were no statistically significant associations between this overexpression and the clinico-pathological parameters analyzed. This finding may reflect the influence of epigenetic events on HSF1 gene or a possible stability of this protein expression throughout disease progression.

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Squamous cell carcinoma (SCC ) is the most common malignancy of the oral cavity (OSCC), with a high mortality rate. Due to this, the discovery of biomarkers that facilitate the understanding of the biological behavior of the tumor and improve treatment is necessary. Urokinase type plasminogen activator (uPA) and its receptor, uPAR, are responsible for the proteolysis of structures of the basement membrana and extracellular matrix, facilitating tumor invasion. This study aims to assess the immuno expression of these proteins in 46 cases of squamous cell carcinoma of the oral tongue (OTSCC). These results were related to the presence of metastasis, clinical TNM staging, locoregional recurrence, outcome of the lesion and histological grading. Immunostaining of each case was evaluated semiquantitatively, in the front of invasion and center of the tumor, in which scores were assigned: 0 (0% of positive cells), 1 (1-10% of positive cells), 2 (11 -50% positive cells) and 3 (more than 50% positive cells). The expression of uPA was observed in 93.5% (n=43) of the cases in the front of invasion, with predominance of score 2 (n=16; 34.8%) and in 67.9% (n=31) of the cases in the center of the tumor, with predominance of score 1 (n=15; 32.6%). Overall, the immunoexpression of uPA was not associated with clinical parameters. Regarding the malignant histological grading, a higher expression of uPA was observed in cases of high-grade malignancy comp ared to low-grade malignancy (p=0.05). Regarding the morphological parameters, increased expression of uPA was observed in the worst mode of invasion (p=0.03 ). The expression of uPAR was observed in 73.9% of cases in the front of invasion, with a predominance of score 1 (n=21; 45.6 %), and in 47.5% (n=21) of the cases in the center of the tumor, with a predominance of score 0 (n=25; 54.4%). Although no statistical differences were observed in relation to lymph node metastasis, clinical TNM staging, outcome, and histological grading, there was a higher expression of uPAR in cases with locoregional recurrence (p=0.04). Regarding the tumor intra -localization, it was observed an increased expression of uPA and uPAR at the front of invasion in relation to the center of the tumor (p<0.001). Regarding the correlation between uPA and uPAR, there was no statistical sign ificance. Based on these results, it is suggested that uPA and uPAR are involved in the progression of CELO, mainly in the deeper region of the tumor.

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Squamous cell carcinoma (SCC ) is the most common malignancy of the oral cavity (OSCC), with a high mortality rate. Due to this, the discovery of biomarkers that facilitate the understanding of the biological behavior of the tumor and improve treatment is necessary. Urokinase type plasminogen activator (uPA) and its receptor, uPAR, are responsible for the proteolysis of structures of the basement membrana and extracellular matrix, facilitating tumor invasion. This study aims to assess the immuno expression of these proteins in 46 cases of squamous cell carcinoma of the oral tongue (OTSCC). These results were related to the presence of metastasis, clinical TNM staging, locoregional recurrence, outcome of the lesion and histological grading. Immunostaining of each case was evaluated semiquantitatively, in the front of invasion and center of the tumor, in which scores were assigned: 0 (0% of positive cells), 1 (1-10% of positive cells), 2 (11 -50% positive cells) and 3 (more than 50% positive cells). The expression of uPA was observed in 93.5% (n=43) of the cases in the front of invasion, with predominance of score 2 (n=16; 34.8%) and in 67.9% (n=31) of the cases in the center of the tumor, with predominance of score 1 (n=15; 32.6%). Overall, the immunoexpression of uPA was not associated with clinical parameters. Regarding the malignant histological grading, a higher expression of uPA was observed in cases of high-grade malignancy comp ared to low-grade malignancy (p=0.05). Regarding the morphological parameters, increased expression of uPA was observed in the worst mode of invasion (p=0.03 ). The expression of uPAR was observed in 73.9% of cases in the front of invasion, with a predominance of score 1 (n=21; 45.6 %), and in 47.5% (n=21) of the cases in the center of the tumor, with a predominance of score 0 (n=25; 54.4%). Although no statistical differences were observed in relation to lymph node metastasis, clinical TNM staging, outcome, and histological grading, there was a higher expression of uPAR in cases with locoregional recurrence (p=0.04). Regarding the tumor intra -localization, it was observed an increased expression of uPA and uPAR at the front of invasion in relation to the center of the tumor (p<0.001). Regarding the correlation between uPA and uPAR, there was no statistical sign ificance. Based on these results, it is suggested that uPA and uPAR are involved in the progression of CELO, mainly in the deeper region of the tumor.

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Objective to evaluate the association between XPD and XRCC3 polymorphisms and oral squamous cell carcinoma (OSCC). Design the sample consisted of 54 cases of OSCC and 40 cases of inflammatory fibrous hyperplasia (IFH). Genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results XPD-Lys/Gln was more common in IFH (n = 28; 70%) than in OSCC (n = 24; 44.4%) (OR: 0.3; p < 0.05). XPD-Gln was more frequent in high-grade lesions (0.48) than in low-grade lesions (0.21) (OR: 3.4; p < 0.05). The Gln/Gln genotype was associated with III and IV clinical stages (OR: 0.07; p < 0.05). XRCC3-Met was more frequent in OSCC (0.49) than in IFH (0.35) (OR: 2.6; p < 0.05). The Met/Met genotype was associated with the presence of metastases (OR: 8.1; p < 0.05) and with III and IV clinical stages (OR: 0.07; p < 0.05). Conclusions in this sample, the frequency of XPD-Gln in IFH suggests that this variant may protect against OSCC. The presence of the XRCC3-Met allele seems to contribute to the development of OSCC, metastases and more advanced stages in these lesions.