RESUMO
OBJECTIVE: To study the anatomical correlation between the arcuate eminence and the superior semicircular canal. MATERIAL AND METHODS: A study of the height of the arcuate eminence was carried out in 295 temporal bones. In addition, 30 temporals with different heights of the arcuate eminence (10 flat, 10 prominent and 10 very prominent) were randomly selected and radiological tests were performed by computed tomography (Pöschl projection) and subsequent dissection by milling until the apex of the superior semicircular canal was found, establishing, with both methods, the anatomical relationship with the arcuate eminence. RESULTS: The arcuate eminence was classified as: smooth, when there was no relief (1.7%); flat, measured less than 1 mm (20.3%), prominent, measured between 1 and 2 mm, in (62%), and very prominent, measured above 2 mm (12.6%). The tomographic study (CT) and its subsequent dissection by bone milling showed a direct relationship between the arcuate eminence and the semicircular canal only when it was flat, while the rest of the types corresponded to the presence of pneumatized peri-labyrinthine cells and/or cancellous bone without a direct anatomical relationship with the apex of the superior semicircular canal. CONCLUSION: The correlation between the arcuate eminence and the superior semicircular canal is direct only when it is flat (1 mm), being related to peri-labyrinthine cells and/or cancellous bone when the arcuate eminence is prominent or very prominent.
Assuntos
Osso Petroso , Canais Semicirculares , Dissecação , Canais Semicirculares/diagnóstico por imagem , Osso Temporal , Tomografia Computadorizada por Raios XRESUMO
To evaluate the potential health issues associated with periodontal disease (PD) in dogs, 1004 teeth from 25 dogs were examined. The dogs were randomly selected, aged 2-14 years, and had at least 95% of their teeth at the first PD stage. Significant positive correlations between plaque grade (PG) and gum inflammation, gingival regression, periodontal pocket, age and serum alanine aminotransferase (ALT) activity were identified. In contrast, PG was negatively correlated to total platelet count. Altogether, these findings suggest that prevention and therapy at the first PD stages can have an important impact on the general health condition of dogs.
Assuntos
Placa Dentária/veterinária , Doenças do Cão/etiologia , Gengivite/veterinária , Doenças Periodontais/veterinária , Animais , Placa Dentária/etiologia , Doenças do Cão/imunologia , Cães , Feminino , Gengivite/etiologia , Gengivite/imunologia , Masculino , Doenças Periodontais/etiologia , Doenças Periodontais/imunologia , EspanhaRESUMO
A non-human dental piece was found in a Roman Empire tomb dated the 3rd century A.C. in Zaragoza (Spain). The morphology of this piece showed mixed brachyodont (carnivores) and hypsodont (herbivores) characteristics. As a result, the taxonomical assignation of the piece was impossible. Therefore, a protocol based on the DNA sequence of the cytochrome c oxidase subunit 1 mitochondrial region (COI) was applied. For this purpose, a pair of primers able to amplify this region in a large variety of animals was designed. The results point to a species of the Genus Bos (Family Bovidae). This assignation was later confirmed by these quencing of a short fragment of the mitochondrial D-loop region. A complete morphological description of the tooth is presented together with the DNA sequence study and comparison protocol.
Assuntos
Bovinos , Dente/anatomia & histologia , Terras Antigas , Animais , Sequência de Bases , Filogenia , Reação em Cadeia da Polimerase , Espanha , Dente/metabolismoRESUMO
The present work proposes a new UHPLC-PDA-fluorescence method able to identify and quantify the main polyphenols present in commercial fruit juices in a 28-min chromatogram. The proposed method improve the IFU method No. 71 used to evaluate anthocyanins profiles of fruit juices. Fruit juices of strawberry, American cranberry, bilberry, sour cherry, black grape, orange, and apple, were analysed identifying 70 of their main polyphenols (23 anthocyanins, 15 flavonols, 6 hydroxybenzoic acids, 14 hydroxycinnamic acids, 4 flavanones, 2 dihydrochalcones, 4 flavan-3-ols and 2 stilbenes). One standard polyphenol of each group was used to calculate individual polyphenol concentration presents in a juice. Total amount of polyphenols in a fruit juice was estimated as total individual polyphenols (TIP). A good correlation (r(2)=0.966) was observed between calculated TIP, and total polyphenols (TP) determined by the well-known colorimetric Folin-Ciocalteu method. In this work, the higher TIP value corresponded to bilberry juice (607.324 mg/100mL fruit juice) and the lower to orange juice (32.638 mg/100mL fruit juice). This method is useful for authentication analyses and for labelling total polyphenols contents of commercial fruit juices.
Assuntos
Bebidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Polifenóis/análiseRESUMO
Mature cactus pears from Opuntia stricta have a dark purple color due to high betacyanin concentration, whose biosynthesis is initiated with the amino acid L-tyrosine as a primary precursor. This study followed the maturation and ripening processes of Opuntia stricta fruits to harvest them at high betacyanin and other antioxidant concentrations. Fruits lasted 9 months for final ripening. Physical and compositional changes at different maturation and ripening stages have been determined. Thus, ripe fruits were around 4.72 ± 0.10 cm length, 2.94 ± 0.05 cm diameter and 22.71 ± 0.20 g weight; moisture and pH were maintained at 87.05 ± 0.19 % and 3.37 ± 0.12, respectively. Purple pigment production started in the ovary of immature fruits four months after anthesis (MAA). Concentration of all analyzed metabolites increased from immature (4 MAA) until ripe (9 MAA) stage. In ripe fruits, reducing sugars were 4.72 ± 0.54 g/100 g ff and total phenols 135.17 ± 0.68 mg gallic acid/100 g ff. Metabolites identified by HPLC were the betacyanins: betanin (60.17 ± 1.08 mg/100 g ff), isobetanin (7.58 ± 0.94 mg/100 g ff) and betanidin (13.48 ± 0.87 mg/100 g ff). Also, L-ascorbic acid (35.03 ± 1.06 mg/100 g ff) and L-tyrosine (4.43 ± 0.73 mg/100 g ff) were determined. Furthermore, the addition of L-tyrosine or L-dopa to fruit pulp of moderately ripe fruits, increased betacyanin concentrations 17 (103.3 ± 3.8 mg/100 g) and 32 % (114.3 ± 4.1 mg/100 g), respectively.
Assuntos
Antioxidantes/análise , Betacianinas/análise , Frutas/química , Opuntia/química , Pigmentos Biológicos/metabolismo , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Betacianinas/isolamento & purificação , Betacianinas/metabolismo , Biomassa , Vias Biossintéticas , Metabolismo dos Carboidratos , Carboidratos/análise , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Levodopa/metabolismo , Opuntia/crescimento & desenvolvimento , Opuntia/metabolismo , Fenóis/análise , Fenóis/isolamento & purificação , Pigmentos Biológicos/análise , Extratos Vegetais/isolamento & purificação , Tirosina/metabolismoRESUMO
We have performed a study on 11 human embryos regarding the development of the tympanic ossicles and their relationship with the first pharyngeal arch. After performing measurements to date the embryos and foetuses chronologically, we performed a meticulous dissection of the temporal bones. Subsequently, they were fixed in 10% formol, decalcified with 2% nitric acid, embedded in Paraplast, sectioned in 7-mm sequences and stained with Martin's trichrome technique. In the 21- and 24-mm cranium-raquis (CR) length human embryos, we have observed the head of the malleus and the body of the incus close to Meckel's cartilage, in addition to the handle of the malleus, the long limb of the incus and the stapes. Between them there was a mesenchymal band inside the primordium of the tympanic cavity. In the 27-mm CR embryo, the various components of the malleus and incus were fusing, and in the 30-mm CR embryo the union was complete. From our observations, we can conclude that the malleus and the incus are derived from the first and second pharyngeal arches.
Assuntos
Região Branquial/anatomia & histologia , Região Branquial/embriologia , Ossículos da Orelha/anatomia & histologia , Ossículos da Orelha/embriologia , Embrião de Mamíferos , Desenvolvimento Fetal/fisiologia , Idade Gestacional , Humanos , Imuno-Histoquímica , Martelo/anatomia & histologia , Martelo/embriologia , Estribo/anatomia & histologia , Estribo/embriologiaRESUMO
OBJECTIVES: To study the ontogenic development of the organisation of the human middle ear ossicles structure. MATERIAL AND METHODS: 46 human temporal bones of ages varying from 32 days post-conception to newborns. RESULTS: The development of the structural organisation of the malleus begins at 16 weeks via two cortical fascicles situated in the neck; at 21 weeks they extend towards the head, at 23 weeks to the lateral process and at 24 weeks to the handle. In the handle, the force lines are transmitted via three cardinal fascicles, two of them via the cortical fascicle and one via the centre, which starts after 29 weeks' development and is consolidated after 31 weeks. In the incus the force lines start at 16 weeks via two cortical fascicles situated in the long process, which progressively extend in a rostro-caudal direction between 17 and 20 weeks. At 21 weeks they occupy the whole extension of the long process and at 22 weeks the fusion of both cortical fascicles begins. From 30 weeks onwards it is strengthened by the crossing of bone trabeculae from one cortical to another. Two fascicles come out of the incus body, surrounding the medullary cavity and going in the direction of the short process. In the beginning, the stapes have two cortical fascicles in their crura. The remodelling process makes the internal cortical fascicle disappear and after 31 weeks all the force lines run through the external cortical fascicle. The tympanic membrane of the stapes footplate undergoes a remodelling process and after 28 weeks bony trabeculae are deposited. In newborns (40 weeks), the ossicles' structure is cavitary and has not been completed. The fan-shaped trabecular fascicle, which starts in the articular facets of the malleus and the incus, still has to develop.
Assuntos
Desenvolvimento Fetal/fisiologia , Bigorna/embriologia , Martelo/embriologia , Estribo/embriologia , Fenômenos Biomecânicos , Idade Gestacional , Humanos , Bigorna/fisiologia , Recém-Nascido , Martelo/fisiologia , Estribo/fisiologiaRESUMO
Fermentation of juice and homogenized fruits of Opuntia stricta fruits has been developed and optimized. The aim was to obtain the red food colorant betanin from prickly pear, at high concentration and low viscosity. Among three strains assayed, Saccharomyces cerevisiae var. bayanus AWRI 796 has been the optimum for this process. The optimum temperature value was found to be 35 degrees C for both sugar consumption and pigment preservation. After fermentation, biomass and residual vegetal tissue were discarded by centrifugation. Supernatant was concentrated under vacuum. Therefore, liquid concentrated betanin was obtained, with low viscosity and being sugar free. Besides, bioethanol was obtained as byproduct. Characteristics of the final product obtained were pH 3.41, 5.2 degrees Brix, 9.65 g/L betanin, color strength of 10.8, and viscosity of 52.5 cP. These values are better than obtained by other procedures.
Assuntos
Betalaínas/análise , Corantes/análise , Fermentação , Frutas/metabolismo , Opuntia/metabolismo , Saccharomyces cerevisiae/metabolismo , Betacianinas/análise , Bebidas/análise , Metabolismo dos Carboidratos , Frutas/química , Opuntia/química , Extratos Vegetais/química , TemperaturaRESUMO
A simple unstructured model, which includes carbon source as the limiting and essential substrate and oxygen as an enhancing substrate for cell growth, has been implemented to depict cell population evolution of two Escherichia coli strains and the expression of their trimethylammonium metabolism in batch and continuous reactors. Although the model is applied to represent the trans-crotonobetaine to L-(-)-carnitine biotransformation, it is also useful for understanding the complete metabolic flow of trimethylammonium compounds in E. coli. Cell growth and biotransformation were studied in both anaerobic and aerobic conditions. For this reason we derived equations to modify the specific growth rate, mu, and the cell yield on the carbon source (glycerol), Y(xg), as oxygen increased the rate of growth. Inhibition functions representing an excess of the glycerol and oxygen were included to depict cell evolution during extreme conditions. As a result, the model fitted experimental data for various growth conditions, including different carbon source concentrations, initial oxygen levels, and the existence of a certain degree of cell death. Moreover, the production of enzymes involved within the E. coli trimethylammonium metabolism and related to trans-crotonobetaine biotransformation was also modeled as a function of both the cell and oxygen concentrations within the system. The model describes all the activities of the different enzymes within the transformed and wild strains, able to produce L-(-)-carnitine from trans-crotonobetaine under both anaerobic and aerobic conditions. Crotonobetaine reductase inhibition by either oxygen or the addition of fumarate as well as its non-reversible catalytic action was taken into consideration. The proposed model was useful for describing the whole set of variables under both growing and resting conditions. Both E. coli strains within membrane high-density reactors were well represented by the model as results matched the experimental data.
Assuntos
Betaína/análogos & derivados , Betaína/metabolismo , Reatores Biológicos , Carnitina/análise , Carnitina/biossíntese , Escherichia coli/crescimento & desenvolvimento , Modelos Biológicos , Algoritmos , Simulação por Computador , Escherichia coli/metabolismo , Fumaratos/metabolismo , Membranas/fisiologia , Complexos Multienzimáticos/antagonistas & inibidores , Oxirredutases/antagonistas & inibidores , Fatores de TempoRESUMO
The L(-)-carnitine production by biotransformation using the recombinant strain Escherichia coli pT7-5KE32 has been studied and optimized with crotonobetaine and D(+)-carnitine as substrates. A resting rather than a growing cells system for L(-)-carnitine production was chosen, crotonobetaine being the best substrate. High biocatalytic activity was obtained after growing the cells under anaerobic conditions at 37 degrees C and with crotonobetaine or L(-)-carnitine as inducer. The growth incubation temperature (37 degrees C) was high enough as to activate the heat-inducible lambdap(L) promoter inserted in the plasmid pGP1-2. The best biotransformation conditions were with resting cells, under aerobiosis, with 4 g l(-1) and 100 mM biomass and substrate concentrations respectively. Under these conditions the biotransformation time (1 h) was shorter and the L(-)-carnitine yield (70%) higher than previously reported. Consequently productivity value (11.3 g l(-1)h(-1)) was highly improved when comparing with other published works. The resting cells could be reused until eight times maintaining product yield levels well over 50% that meant to increase ten times the L(-)-carnitine obtained per gram of biomass.
RESUMO
The paper is a review of the jugulotympanic paragangliomata seen in our Hospital in a 2 years term. The AA. discuss every case and achieve a checking of several therapeutics procedures accepted for these growths.
Assuntos
Neoplasias da Orelha/diagnóstico , Orelha Média , Tumor do Glomo Jugular/diagnóstico , Neoplasias Primárias Múltiplas/diagnóstico , Paraganglioma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
A flow injection analysis method for determining L-carnitine is reported. The system uses the enzyme L-carnitine dehydrogenase covalently immobilized to Eupergit C. The NADH produced by the action of the enzyme, which is proportional to the L-carnitine concentration, is quantified using fluorescence detection. The system response was rapid and had a wide range of linearity. At a flow rate of 0.2 ml/min, a detection limit of 1 microM (20 pmol) was obtained for L-carnitine, peak areas were linear up to 100 microM, and samples could be injected every 4 min. The method performed well as a routine assay, showing high sensitivity (54,000 AU/microM), a precision of 0.96%, and the ability to carry out 144 consecutive assays with an RSD of 1.47% (good stability). Comparisons were made with other known methods for L-carnitine determination. Presence of D-carnitine had no effect on L-carnitine assay. The analysis was valid for determining L-carnitine concentrations in commercial pharmaceutical preparations.
Assuntos
Carnitina/análise , Análise de Injeção de Fluxo/métodos , NAD/análise , Oxirredutases do Álcool/química , Calibragem , Enzimas Imobilizadas/química , Preparações Farmacêuticas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de FluorescênciaRESUMO
An enzymatic method for d-carnitine determination using the enzyme d-carnitine dehydrogenase is described. The assay is based on the amplified signal produced during NAD(+) cycling in the presence of a tetrazolium salt and using phenazine methosulfate as electron carrier. Optimum assay conditions were studied with two tetrazolium salt pairs: 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT)/MTT-formazan and 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl tetrazolium chloride (INT)/INT-formazan. The first pair (MTT) showed higher sensitivity. The calibration curve was linear from 0.1 to 5 mM d-carnitine, with a quantification limit of 0.1 mM and a relative standard deviation of 1.51%. The procedure is simple, rapid, accurate, and easily automated. It was satisfactorily applied to following d-carnitine levels during the microbial transformation of d-carnitine into l-carnitine and to determining the d-carnitine content of pharmaceutical preparations.
Assuntos
Oxirredutases do Álcool , Carnitina/análise , Oxirredutases do Álcool/isolamento & purificação , Oxirredutases do Álcool/metabolismo , Automação , Biotransformação , Carnitina O-Acetiltransferase/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Formazans , Indicadores e Reagentes , Cinética , NAD/metabolismo , Reprodutibilidade dos Testes , Rhizobium/enzimologia , Sensibilidade e Especificidade , Espectrofotometria/métodos , EstereoisomerismoRESUMO
The use of a biological procedure for L-carnitine production as an alternative to chemical methods must be accompanied by an efficient and highly productive reaction system. Continuous L-carnitine production from crotonobetaine was studied in a cell-recycle reactor with Escherichia coli O44 K74 as biocatalyst. This bioreactor, running under the optimum medium composition (25 mM fumarate, 5 g/l peptone), was able to reach a high cell density (26 g dry weight/l) and therefore to obtain high productivity values (6.2 g L-carnitine l-1 h-1). This process showed its feasibility for industrial L-carnitine production. In addition, resting cells maintained in continuous operation, with crotonobetaine as the only medium component, kept their biocatalytic capacity for 4 days, but the biotransformation capacity decreased progressively when this particular method of cultivation was used.
Assuntos
Aciltransferases , Reatores Biológicos , Carnitina/biossíntese , Escherichia coli/enzimologia , Escherichia coli/crescimento & desenvolvimento , Microbiologia Industrial , Anaerobiose , Betaína/análogos & derivados , Betaína/metabolismo , Meios de Cultura , Indução Enzimática , Hidroliases/metabolismoRESUMO
Crouzon's syndrome is a chapter of the craneosynostosis, congenital diseases characterized for the precocious closure of cranial sutures. It represents an autosomal dominant heredity. Recently has been find out that the mutation lies in the short arm of chromosome 10, which causes the alteration of type 2 receptor of growth factor of fibroblasts (FRFG2). Clinically together with the cranial deformities appear frequently malformations in ENT-sphere, but only in 3 percent of all cases has been observed otic changes. We present the case of a young girl of 16, bearing a Crouzon's syndrome, coming to our office because of bilateral hypacusis. Clinical examination and complementary tests showed bilateral atresia of both auditive meatus lack of mastoid pneumatization, anomalous facial route and heavy bilateral transmissive hearing impairment, together with septum nasi deflection and hypoplasy of paranasal sinuses.
Assuntos
Disostose Craniofacial/complicações , Disostose Craniofacial/diagnóstico , Perda Auditiva Neurossensorial/etiologia , Obstrução Nasal/etiologia , Adolescente , Audiometria de Tons Puros , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Cromossomos Humanos Par 12/genética , Disostose Craniofacial/genética , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Obstrução Nasal/diagnóstico , Septo Nasal/anormalidades , Mutação Puntual/genética , Tomografia Computadorizada por Raios XRESUMO
NAD(H) was retained in a noncharged ultrafiltration membrane reactor for the simultaneous and continuous production of L-lactate and gluconate with coenzyme regeneration. Polyethyleneimine (PEI), a 50-kDa cationic polymer, achieved coenzyme retentions above 0.8 for PEI/NAD(H) molar ratios higher than 5. The ionic strength of the inlet medium caused a decrease of NAD(H) retention that can be counterbalanced by an initial addition of 1% bovine serum albumin (BSA). Continuous reactor performance in the presence of PEI and BSA showed that NAD(H), glucose dehydrogenase, and lactate dehydrogenase were retained by 10-kDa ultrafiltration membranes; L-lactate and gluconate were produced at conversions higher than 95%. PEI enhanced the thermal stability of the enzymes used and increased the catalytic efficiency of glucose dehydrogenase, while no effect was found on the kinetic parameters of lactate dehydrogenase. A model that implements the kinetic equations of the two enzymes describes the reactor behavior satisfactorily. In brief, the use of PEI to retain NAD(H) is a new interesting approach to be widely applied in continuous synthesis with the large number of known dehydrogenases.
Assuntos
Reatores Biológicos , Gluconatos/metabolismo , Ácido Láctico/biossíntese , NAD/metabolismo , Ultrafiltração/métodos , Biotecnologia/métodos , Estabilidade Enzimática/efeitos dos fármacos , Glucose 1-Desidrogenase , Glucose Desidrogenase/química , Glucose Desidrogenase/metabolismo , Cinética , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/metabolismo , Membranas , Modelos Biológicos , NAD/química , Polietilenoimina/química , Polietilenoimina/metabolismo , Polietilenoimina/farmacologiaRESUMO
A retrospective review was made of 719 primary stapedectomies and 48 re-operations carried out between 1975 and 1993. Preoperative and postoperative audiograms (6-12 months) were studied, analyzing 250, 500, 1000, 2000 and 4000 Hz, auditory gain and closure of the air-bone gap < or = 10 dB. Ninety percent had an auditory gain of > or = 10 dB at conversational frequencies. Age, the surgeon, and average preoperative pure tone did not influence the final result. Polyethylene prostheses (70.9%) and steel and teflon pistons (21.1%) were the prostheses used most often. Neurosensorial hearing loss (> 10 dB) occurred in 24 cases (3.3%). In revision stapedectomy, 66.6% of patients had air-bone gap closure of < or = 20 dB and 71% had a hearing gain of < or = 10 dB. Prosthesis displacement (43.7%) and incus necrosis (18.7%) were the most common findings in revision stapedectomy.
Assuntos
Otosclerose/cirurgia , Cirurgia do Estribo , Adulto , Idoso , Audiometria de Tons Puros , Condução Óssea , Feminino , Transtornos da Audição , Perda Auditiva Condutiva/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos RetrospectivosRESUMO
This is a retrospective study dealing with 719 primary stapedectomies and 48 reoperations done between 1975 and 1993 by the AA. of the paper. They consider the audiometric tracings before and after surgery (6 and 12 months). Frequencies analyzed were 250 Hz, 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz; the air-bone gap; and modifications of bone thresholds. The patients were ranged in groups according the ages and previous bone thresholds. Thereafter an analysis aiming to a comparison of surgery results en each group was contemplated. The age resulted without influence on the postoperative gap neither in modifications of bone conduction. The previous bone thresholds nor influencing the final gap. Conversely there are significative differences (P > 0.01) regarding the modifications of bone conduction.
Assuntos
Cirurgia do Estribo , Adulto , Fatores Etários , Idoso , Feminino , Perda Auditiva Condutiva/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos RetrospectivosRESUMO
A study of the patients who, through a year, came to the Emergencies Department showing foreign bodies in ENT-area has been accomplished. Among ENT urgencies foreign bodies constitute the most frequent cases. Age, sex, date, time of admission, sitting, kind of body and treatment are taken in consideration. The intruders were most commonly found in the pharyngeal area. A striking correspondence between age and location is underlined.
Assuntos
Corpos Estranhos/epidemiologia , Corpos Estranhos/fisiopatologia , Laringe/fisiopatologia , Adulto , Fatores Etários , Criança , Orelha/fisiopatologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/fisiopatologia , Estudos Retrospectivos , Espanha/epidemiologiaRESUMO
Mucous melanoma in the nasal cavity are unusual tumours that develop from common melanocytes pre-existent in the respiratory epithelium. They manifest a high diagnostic and therapeutic difficulties as well as an obscure prognosis. A case of this rare tumour is exposed and a bibliographic review in which clinical, diagnostic, histological, therapeutic and prognostic features are contemplated.