963 resultados para salivary gland neoplasm


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BACKGROUND: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Most ectopic thyroids are revealed by congenital hypothyroidism and present as a single round mass at the base of the tongue, with no other thyroid tissue. However, some cases have dual ectopy, with part of the tissue having partially migrated. We hypothesized that this occurs more frequently than previously reported.¦METHODS: To determine the prevalence of dual ectopy, we reviewed the pertechnetate scintigraphies of 81 patients with congenital hypothyroidism from thyroid ectopy diagnosed between 2002 and 2011 at our institution.¦RESULTS: We report a series of seven cases (9%) of dual ectopy, representing an incidence ranging from 1:50,000 to 1:70,000.¦CONCLUSIONS: Almost one in 10 cases with congenital hypothyroidism due to thyroid ectopy has dual ectopy. This suggests that two populations of cells diverged at an early stage of development, which may arise from insufficient signaling gradients in surrounding tissues during early organogenesis or may indirectly support the polyclonal nature of the thyroid.

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The present study evaluates the use of salivary cortisol concentration as a physiological index of the stress level among nurses on their work day and day off and correlates it with the questionnaire used to measure occupational stress in nurses (Inventário de Estresse em Enfermeiros - IEE). This is a comparative, cross-sectional descriptive study in which sociodemographic data, IEE results and salivary cortisol levels were used. Fifty-seven nurses participated in the study (80.7% females and a mean age of 37.1 years old). The IEE average score was 124.5. The average cortisol level was 564.1 ng/m on work day and 354.1 ng/mL on day off. Nurses who had double workdays presented high values of salivary cortisol during the work day (638.1 ng/mL). In conclusion, salivary cortisol identified the nurses’ stress level, and differences were found between a work day and day off. On the nurses’ day off, their salivary cortisol levels and stress scores were lower.

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Several cases of Brunner's gland hyperplasia causing hemorrhage, obstruction, or intussusception have been published in the adult literature. Similar cases in the pediatric population are very rare and have only been described twice, always associated with chronic renal failure. We report the third and youngest case of gastric outlet obstruction because of Brunner's gland hyperplasia focusing on histopathologic condition and treatment based on a review of the literature.

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The occurrence, morphology and ultrastructure of the Dufour gland in Melipona bicolor Lepeletier, 1836 are presented. The Dufour gland is not present in workers. In virgin queens the gland cells show characteristics of low activity, which are described in the text. In physogastric queens the gland epithelium is higher and the cells more active than in virgin queens, showing numerous basal plasmic membrane invaginations impregnated by an electrondense material, increased apical invaginations and accumulation of substances that will be released to the gland lumen in the subcuticular space. Therefore, the data show that the Dufour gland is more developed in physogastric than in virgin queens, indicating a possible involvement of the Dufour gland in the reproduction of this species.

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Neuroblastoma (NB) is a heterogeneous, and particularly malignant childhood neoplasm in its higher stages, with a propensity to form metastasis in selected organs, in particular liver and bone marrow, and for which there is still no efficient treatment available beyond surgery. Recent evidence indicates that the CXCR4/CXCL12 chemokine/receptor axis may be involved in promoting NB invasion and metastasis. In this study, we explored the potential role of CXCR4 in the malignant behaviour of NB, using a combination of in vitro functional analyses and in vivo growth and metastasis assessment in an orthotopic NB mouse model. We show here that CXCR4 overexpression in non-metastatic CXCR4-negative NB cells IGR-NB8 and in moderately metastatic, CXCR4 expressing NB cells IGR-N91, strongly increased tumour growth of primary tumours and liver metastases, without altering the frequency or the pattern of metastasis. Moreover shRNA-mediated knock-down experiments confirmed our observations by showing that silencing CXCR4 in NB cells impairs in vitro and almost abrogates in vivo growth. High levels of CXCL12 were detected in the mouse adrenal gland (the primary tumour site), and in the liver suggesting a paracrine effect of host-derived CXCL12 on NB growth. In conclusion, this study reveals a yet unreported NB-specific predominant growth and survival-promoting role of CXCR4, which warrants a critical reconsideration of the role of CXCR4 in the malignant behaviour of NB and other cancers.

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Morphological, chemical and developmental aspects of the Dufour gland in some eusocial bees (Hymenoptera, Apidae): a review. The present revision focused on the more recent data about the Dufour gland in some eusocial bees, taking in account general aspects of its morphology, secretion chemical nature, bio-synthetic pathway and development. Many functions have been attributed to this gland in eusocial bees, but none are convincing. With the new data about this gland, not only the secretion chemical pathway of the Dufour gland may be reasonable understood, as its function in some eusocial bees, especially Apis mellifera Linné, 1758, which has been extensively studied in the last years.

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Laboratory studies were conducted to compare rostrum length morphology of mandible serration and area of food and salivary canals of Dichelops melacanthus (Dallas) (Dm), Euschistus heros (F.) (Eh), Nezara viridula (L.) (Nv), and Piezodorus guildinii (Westwood) (Pg) (Heteroptera: Pentatomidae). Nv showed the longest (5.9 mm) and Pg the shortest (3.5 mm) rostrum length; Dm and Eh were intermediate. Length and width of mandible tip areas holding serration was bigger for Nv (106.0 and 30.2 µm, respectively) and smaller for Pg (71.1 and 23.7 µm), with all species having four central teeth and three pairs of lateral teeth. The inner mandible surface showed squamous texture. Cross-section of food and salivary canals (Fc and Sc) indicated greater area for Nv and Dm compared to Eh and Pg; however, the ratio Fc/Sc, yielded the highest relative area for Pg.

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Adenoid cystic carcinoma of the lacrimal gland. BACKGROUND: Adenoid cystic carcinoma is the most frequent epithelial tumour of the lacrimal gland. It represents 1.6 % of the orbital tumours. The aim of this study is to present a series of such patients who were followed up in our clinic and to discuss their clinical management in order to achieve a better life prognosis. MATERIALS AND METHODS: The cases we followed up in our department were presented, the treatment modalities were discussed, and conclusions were drawn. RESULTS: Six patients with this pathology were examined, 3 men and 3 women, aged 31 to 69 years. A large excision was performed in 5 patients (exenteration alone or extended exenteration with complementary radiotherapy) and in 1 patient with excision of the tumour followed by radiotherapy. One patient died due to carcinoma six years after the first surgery. The median follow-up period of our cases is 25 months. CONCLUSION: Adenoid cystic carcinoma of the lacrimal gland is a malignant tumour with a reserved prognosis. Various treatments were proposed to improve the mortality rate of the disease. At present radical surgery with or without complementary therapy seems to give the best chances of healing, at least with short or mid-term follow-up.

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Purpose: Involvement of salivary glands with mucosa-associated lymphoid tissue (MALT) lymphoma is rare. This retrospective study was performed to assess the clinical profile, treatment outcome, and prognostic factors of MALT lymphoma of the salivary glands.Methods and Materials: Thirteen member centers of the Rare Cancer Network from 10 countries participated, providing data on 63 patients. The median age was 58 years; 47 patients were female and 16 were male. The parotid glands were involved in 49 cases, submandibular in 15, and minor glands in 3. Multiple glands were involved in 9 patients. Staging was as follows: IE in 34, IIE in 12, IIIE in 2, and IV in 15 patients.Results: Surgery (S) alone was performed in 9, radiotherapy (RI) alone in 8, and chemotherapy (CT) alone in 4 patients. Forty-one patients received combined modality treatment (S + RT in 23, S + CT in 8, RT + CT in 4, and all three modalities in 6 patients). No active treatment was given in one case. After initial treatment there was no tumor in 57 patients and residual tumor in 5. Tumor progression was observed in 23 (36.5%) (local in 1, other salivary glands in 10, lymph nodes in 11, and elsewhere in 6). Five patients died of disease progression and the other 5 of other causes. The 5-year disease-free survival, disease-specific survival, and overall survival were 54.4%, 93.2%, and 81.7%, respectively. Factors influencing disease-free survival were use of RI, stage, and residual tumor (p < 0.01). Factors influencing disease-specific survival were stage, recurrence, and residual tumor (p < 0.01).Conclusions: To our knowledge, this report represents the largest series of MALT lymphomas of the salivary glands published to date. This disease may involve all salivary glands either initially or subsequently in 30% of patients. Recurrences may occur in up to 35% of patients at 5 years; however, survival is not affected. Radiotherapy is the only treatment modality that improves disease-free survival. (C) 2012 Elsevier Inc.

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According to recent crystallographic studies, the TCR-alpha beta contacts MHC class I-bound antigenic peptides via the polymorphic V gene-encoded complementarity-determining region 1 beta (CDR1 beta) and the hypervariable (D)J-encoded CDR3 beta and CDR3 alpha domains. To evaluate directly the relative importance of CDR1 beta polymorphism on the fine specificity of T cell responses in vivo, we have taken advantage of congenic V beta a and V beta b mouse strains that differ by a CDR1 polymorphism in the V beta 10 gene segment. The V beta 10-restricted CD8+ T cell response to a defined immunodominant epitope was dramatically reduced in V beta a compared with V beta b mice, as measured either by the expansion of V beta 10+ cells or by the binding of MHC-peptide tetramers. These data indicate that V beta polymorphism has an important impact on TCR-ligand binding in vivo, presumably by modifying the affinity of CDR1 beta-peptide interactions.

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Different interactions have been described between glucocorticoids and the product of the ob gene leptin. Leptin can inhibit the activation of the hypothalamo-pituitary-adrenal axis by stressful stimuli, whereas adrenal glucocorticoids stimulate leptin production by the adipocyte. The present study was designed to investigate the potential direct effects of leptin to modulate glucocorticoid production by the adrenal. Human adrenal glands from kidney transplant donors were dissociated, and isolated primary cells were studied in vitro. These cells were preincubated with recombinant leptin (10(-10)-10(-7) M) for 6 or 24 h, and basal or ACTH-stimulated cortisol secretion was subsequently measured. Basal cortisol secretion was unaffected by leptin, but a significant and dose-dependent inhibition of ACTH-stimulated cortisol secretion was observed [down by 29 +/- 0.1% of controls with the highest leptin dose, P &lt; 0.01 vs. CT (unrelated positive control)]. This effect of leptin was also observed in rat primary adrenocortical cells, where leptin inhibited stimulated corticosterone secretion in a dose-dependent manner (down by 46 +/- 0.1% of controls with the highest leptin dose, P &lt; 0.001 vs. CT). These effects of leptin in adrenal cells are likely mediated by the long isoform of the leptin receptor (OB-R), because its transcript was found to be expressed in the adrenal tissue and leptin had no inhibitory effect in adrenal glands obtained from db/db mice. Therefore, leptin inhibits directly stimulated cortisol secretion from human and rat adrenal glands, and this may represent an important mechanism to modulate glucocorticoid levels in various metabolic states.

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ÁBSTRACT : Mammary gland is composed of two main epithelial cell types, myoepithelial and luminal. The mechanisms involved in determination and maintenance of them remain poorly understood. Notch signaling is known to regulate cell fate determination in other tissues like skin and nervous system. It was also shown that it can act as tumor suppressor or oncogene depending on the tissue type. The mouse models overexpressing active Notch receptors indicated that Notch signaling is oncogenic in the mammary gland. This observation was followed by some descriptive and functional studies in human breast cancer and it was reported that Notch signaling activity or expression of its components are increased in some of the breast tumor samples compared to normal tissue. However, the physiological role of the Notch signaling and its downstream mechanisms in mammary gland is poorly defined. p63, a member of p53 family, has been implicated in the cell fate determination of keratinocytes. Knockout mouse models revealed that p63 is required for the formation of the mammary anlagen in embryo and its ΔN isoform is expressed exclusively in the myoepithelial layer of the adult breast. In order to understand its function in normal breast epithelial cells, I activated Notch signaling by expression of Notch1 intracellular domain (NICD) in normal primary human breast epithelial cells (HBECs). In this context, NICD reduced growth of HBECs and led to downmodulation of extracellular matrix-receptor interaction network (ECM) components as well as ΔNp63. Expression of ΔNp63 together with NICD partially rescued Notch induced growth reduction, which was correlated with an increase in ECM components. Moreover, silencing ΔNp63 in myoepithelial HBECs reduced growth similar to Notch activation and it led to downregulation of myoepithelial and upregulation of luminal markers. Complementing this observation, forced expression of ONp63 in luminal HBECs induced myoepithelial phenotype and decreased luminal markers. In vivo, by the analysis of a Notch reporter mouse strain, I showed that Notch is activated during puberty specifically at the sites of ductal morphogenesis, terminal end buds. FAGS analysis revealed that it can be detected in two different populations based on CD24 expression (low (lo) or high (high)): at lower levels in CD24lo, which includes stem/progenitor and myoepithelial cells and higher levels in CD24hi, which contains luminal cells. In parallel with in vitro results, the CD24lo mouse mammary epithelial cells displaying Notch activity have lower levels of p63 expression. Furthermore, deletion of RBPjk, the main mediator of Notch signaling, or the overexpression of ΔNp63 inhibited luminal cell lineage in vivo. Another important point revealed by Notch reporter mouse strain is the simultaneous activation of Notch with estrogen signaling during pubertal development. The expression of FOXA1, the mediator of estrogen receptor (ER) transcriptional activity, is correlated with Notch activation in vivo that it is lower in CD24lo than in CD24hi cells. Moreover, FOXA1 is regulated by NICD in vitro supporting the presence of a link between Notch and ER signaling. Taken together, I report that Notch signaling is involved in luminal cell fate determination and its effects are partially mediated through inhibition of ONp63. Besides, ΔNp63 is required for the maintenance and sufficient for the induction of myoepithelial phenotype in HBECs in vitro and is not compatible with luminal lineage in vivo. Based on these results, I propose a model for epithelial cell hierarchy in mammary gland, whereby there are two different types of luminal progenitors, early and late, displaying different levels of Notch activity. Notch signaling contributes to the determination of luminal cell lineage in these two progenitor steps: In "Early Luminal Progenitor" stage, it inhibits myoepithelial fate by decreasing p63 expression, and in "Late Luminal Progenitor" stage, Notch signaling is involved in induction of luminal lineage by acting on ER-FOXA1 axis. It has to be investigated further whether Notch signaling might behave as an oncogene or tumor suppressor depending on which cell type in the epithelial hierarchy it is modulated and which one is more likely to occur in different human breast cancer types. RÉSUMÉ : La glande mammaire est composée de deux types principaux de cellules: les cellules luminales, qui bordent le lumen et les cellules myoépithéliales, qui se trouvent entre la lame basale et les cellules luminales. Les mécanismes intervenant dans leur différenciation et leur maintenance demeurent encore mal compris. La protéine transmembranaire Notch est connue pour déterminer le destin des cellules dans plusieurs types de tissus comme la peau ou le système nerveux. Selon le type de tissu dans lequel se trouve Notch, il agira soit comme un suppresseur de tumeur soit comme un oncogène. A l'aide de modèles de souris surexprimant les récepteurs actifs de Notch, il a été démontré que la voie de signalisation de Notch est oncogénique au niveau de la glande mammaire. Des études descriptives et fonctionnelles dans le cadre du cancer du sein ont permis de mettre en évidence une augmentation de l'activité de Notch ou de l'expression de ces composants dans certains tissus cancéreux. Toutefois, le rôle physiologique de Notch et des mécanismes qu'il active restent méconnus. P63, une protéine membre de la famille p53, est impliquée dans la différenciation des kératinocytes. Le modèle issu de l'étude des souris p63 knockout a révélé que cette protéine est requise pour la formation des primordia mammaires chez l'embryon et que son isoforme ΔNp63 est exclusivement exprimée dans la couche myoépithéliale de la glande mammaire adulte. Dans le but de comprendre les fonctions physiologiques de Notch, je l'ai activé en exprimant le domaine intracellulaire de Notch 1 (NICD) dans des cellules épithéliales primaires de glande mammaire humaine (HBECs). Le NICD a alors réduit la croissance des HBECs et conduit à la régulation négative non seulement de p63 mais également des composants du réseau d'interaction des récepteurs de la matrice extracellulaire (ECM). En exprimant conjointement ΔNp63 et NICD, il est apparu que la réduction de croissance induite par Notch était partiellement compensée, et qu'il y avait également une augmentation des composants ECM. De plus, lorsque ΔNp63 a été inactivé dans les cellules HBECs myoépithéliales, une réduction de croissance cellulaire identique à celle provoquée par l'activation de Notch a pu être mise en évidence, de même qu'une régulation négative des marqueurs myoépithéliaux ainsi qu'une augmentation des marqueurs luminaux. Afin de compléter ces informations, l'expression de ΔNp63 a été forcée dans les HBECs luminales, ce qui a induit un phénotype myoépithélial et une diminution des marqueurs lumineux. In vivo, par l'analyse de souris ayant un gène rapporteur de l'activité de Notch, j'ai démontré que Notch est activé pendant la puberté au niveau des sites de la morphogenèse canalaire, à savoir les bourgeons terminaux. Les analyses par FACS (Fluorescence-activated cell sorting) basées sur l'expression de l'antigène CD24 ont révélé qu'il peut tre détecté dans deux populations différentes : une population qui l'exprime faiblement, qui regroupe les cellules souches/progéniteurs et les cellules myoépithéliales, et une population qui l'exprime fortement qui est composé des cellules luminales. Parallèlement aux résultats in vitro, j'ai mis en évidence un faible niveau d'expression de p63 dans les cellules épithéliales de la glande mammaire de souris, exprimant faiblement l'antigène CD24 et présentant une activité de Notch. De plus, la délétion de RBPjr~, médiateur principal de la signalisation de Notch, ainsi que la surexpression de ΔNp63 in vivo ont inhibé la lignée des cellules luminales. Un autre point important révélé par les souris rapporteur de l'activité de Notch a été l'activation simultanée de Notch et de la signalisation de l'oestrogène pendant le développement pubertaire. L'expression de FOXA1, médiateur de l'activité transcriptionnelle des récepteurs aux oestrogènes (ER), est en corrélation avec l'activation de Notch in vivo, plus basse dans les cellules avec une faible expression de l'antigène CD24 que dans celles avec une forte expression. De plus, FOXA1 est régulé par NICD in vitro confirmant la présence d'un lien entre Notch et la signalisation des ER. En résumé, la signalisation de Notch est impliquée dans la détermination du destin cellulaire des cellules luminales et ses effets sont partiellement modifiés par l'inhibition de ΔNp63. ΔNp63 est requis pour la maintenance et est suffisant pour l'induction du phénotype myoépithéliale dans les HBECs in vitro et ne peut donc pas se trouver dans les cellules luminales in vivo. Basé sur ces résultats, je propose un modèle de hiérarchisation des cellules épithéliales de la glande mammaire, dans lequel sont présents deux types de progéniteurs des cellules luminales exprimant des niveaux différents d'activité de Notch, les progéniteurs lumineux précoces et tardifs. La signalisation de Notch contribue à la différenciation de la lignée cellulaire luminale au niveau de ces deux progéniteurs : dans la forme précoce, il inhibe la différenciation des cellules myoépithéliales en réduisant l'expression de p63 et dans la forme tardive, Notch est impliqué dans l'induction de la lignée luminale en agissant sur l'axe ER-FOXA1. Il serait nécessaire d'investiguer plus loin si le fait que Notch agisse comme oncogène ou suppresseur de tumeur dépend du stade de différenciation de la cellule dans laquelle il est modulé et laquelle de ces deux fonctions il est le plus probable de rencontrer dans les différents types de cancer du sein.