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Publications (7)9.43 Total impact

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    ABSTRACT: To analyze soluble and membrane-bound peptidase activities in the tonsils and adenoids removed from patients with adenoid hyperplasia, tonsillar hyperplasia and chronic tonsillitis. A total of 48 tissue samples from patients undergoing adenoidectomy and tonsillectomy for adenoid hyperplasia, tonsillar hyperplasia or chronic tonsillitis were analyzed. The catalytic activity of a pool of peptidases in the soluble (dipeptidyl peptidase IV, aminopeptidase A, aminopeptidase N and cystinyl aminopeptidase) and membrane-bound (prolyl endopeptidase, aspartyl aminopeptidase, aminopeptidase B and pyroglutamyl peptidase I) fractions was measured fluorometrically. The activity of membrane-bound aminopeptidase B was higher in cases of chronic tonsillitis and adenoid hyperplasia than in tonsillar hyperplasia, p=0.004. Soluble dipeptidyl peptidase IV and membrane-bound pyroglutamyl peptidase I were found to be more active in tissues from male chronic tonsillitis tissues, p<0.05, while membrane-bound aminopeptidase B activity was higher in tissues of females with tonsillar hyperplasia, p<0.001. In the case of chronic tonsillitis, soluble aminopeptidase A was found to have a higher level of activity in tissues from children than those from adults, p=0.005. Our results suggest a potential role of soluble aminopeptidase A, soluble dipeptidyl peptidase IV, membrane-bound aminopeptidase B and membrane-bound pyroglutamyl peptidase I in the pathobiology of adenoid hyperplasia, tonsillar hyperplasia and chronic tonsillitis that is differently regulated as a function of gender. These finfings may modify in the future the clinical approach to these diseases.
    International journal of pediatric otorhinolaryngology 09/2011; 75(11):1399-403. · 0.85 Impact Factor
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    ABSTRACT: Chylous fistula is a serious complication of neck surgery. The aim of this study was to analyse the incidence, treatment and evolution of chylous fistula in neck dissection. We conducted a retrospective study of 304 patients, 295 (97.03%) men and nine (2.97%) women. Ages ranged from 24 to 80 years (mean = 59.28 years, SD = 6.02) and they had all undergone neck dissection. Chylous fistula occurred in four cases (1.31%). Incidence was 1.83% in laryngeal cancer and 2.7% in oral cavity and oropharyngeal cancer. No statistically significant correlation was found between tumoral stage and fistula occurrence. Radiotherapy prior to surgery was a risk factor although the association was not statistically significant. The incidence rates for radical and functional neck dissection were 3.3% and 0.46%, respectively, statistically significant (P = 0.042). The fistulas were located on the left side in all cases. One of the four patients required surgical intervention and another one died. The occurrence of chylous fistula increased significantly the length of hospital stay (P = 0.01). Chylous fistulas appear on the left side, radiotherapy prior to surgery is a risk factor and there is not correlation with tumoral stage. Chylous fistulas are significantly more common in radical than in functional dissections and increase significantly the length of hospital stay.
    European Journal of Cancer Care 07/2010; 19(4):510-5. · 1.31 Impact Factor
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    ABSTRACT: Prolyl endopeptidase (EC 3.4.21.26) (PEP) is a serine peptidase that converts several biologically active peptides. This enzyme has been linked to several neurological, digestive, cardiovascular and infectous disorders. However, little is known about its involvement in neoplastic processes. This study analyzes fluorimetrically cytosolic and membrane-bound PEP activity in a large series (n=122) of normal and neoplastic tissues from the kidney, colon, oral cavity, larynx, thyroid gland and testis. Cytosolic PEP activity significantly increased in clear cell renal cell carcinoma, urothelial carcinoma of the renal pelvis and head and neck squamous cell carcinoma. Both cytosolic and membrane-bound PEP activity were also increased in colorectal adenomatous polyps. These data suggest the involvement of PEP in some mechanisms that underlie neoplastic processes.
    Regulatory Peptides 03/2010; 163(1-3):102-6. · 2.06 Impact Factor
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    ABSTRACT: Involvement of peptidases in carcinogenic processes of several tumor types has been investigated in recent years. Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide and accounts for more than 90% of all head and neck cancers. Increased understanding of its pathophysiology has led to implication of several proteinases, specially matrix metalloproteinases, in its genesis, growth, and dissemination. However, very little is known about involvement of peptidases in this neoplasm. Seventeen HNSCC tissue samples were selected for the study. Tumor and normal tissue samples were frozen for enzymatic study. The catalytic activity for a pool of peptidases (PSA, APN/CD13, APB, APA, Asp-AP, CAP, DPPIV/CD26, NEP/CD10, and PGI) was measured fluorometrically. The activity of 2 cell surface aminopeptidases (APN/CD13 and APA) and a cytosolic aminopeptidase (Asp-AP) was significantly increased in HNSCC tissues. These data show the involvement of cell surface and cytosolic peptidases in the mechanisms underlying HNSCC.
    Head & Neck 05/2009; 31(10):1335-40. · 2.83 Impact Factor
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    ABSTRACT: SUMMARY: BACKGROUND: Metastatic tumors account for less than 1% of all malignant tumors occurring in the oral cavity. CASE REPORT: The clinical case of a 94-year-old patient with a mandibular tumor is reported here. The patient had undergone bilateral mastectomy more than 25 years before. An immunohistochemical study found hormone receptors in signet ring cells, suggesting a diagnosis of breast cancer metastasis. CONCLUSION: Immunohistochemical diagnosis and antineoplastic hormone therapy is the cornerstone in the management of this clinical case.
    Breast Care 01/2009; 4(3):192-194. · 0.68 Impact Factor
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    ABSTRACT: Percutaneous embolization reduces the reappearance of epistaxis and the mean length of hospital stay for patients with intractable epistaxis or juvenile nasopharyngeal angiofibroma (JNA). To assess whether percutaneous embolization is effective for the treatment of intractable epistaxis and JNA. Twenty-eight patients with intractable posterior epistaxis treated by embolization (25 males; m = 59.78 years; SD = 14.3) and 28 unembolized patients (24 males; m = 59.21 years; SD = 15.13) were studied retrospectively. Eight patients with JNA (all males; mean = 16.5 years; SD = 2.35; four embolized before surgery and four unembolized) were also analyzed. Embolization was bilateral in 71.4% of subjects, blood transfusion was required in 28.57%, incidence of complications was 53.57%, and seven of the embolized patients with intractable epistaxis suffered from recurrence of the epistaxis. There were no statistically significant differences between the embolized and unembolized groups. The mean hospital stay was longer in unembolized patients (4.46 days; SD = 2.42) than for the embolized patients (3.78 days; SD = 3.9), p=0.394. The most serious complications occurred in patients embolized with idiopathic epistaxis and the mean post-embolization hospital stay was longer in this subgroup (4.14 days; SD = 4.39) than in patients with Rendu-Osler-Weber syndrome (2.40 days; SD = 1.140), p=0.395. Unembolized patients with JNA presented greater hemorrhage (m = 2025 ml; SD = 325) and a longer mean hospital stay (m = 18 days; SD = 3) than the group of embolized patients (m = 360 ml; SD = 185 and m = 9 days; SD = 1, respectively).
    Acta oto-laryngologica 01/2009; 129(12):1456-62. · 0.98 Impact Factor
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    ABSTRACT: Introduction: Inflammatory myofibroblastic tumor (IMFT) of the temporal bone is an unusual but distinct clinicopathologic entity. Case Report: We report the case of a 75-year-old patient with an IMFT located in the temporal bone. Symptoms included VI, X, XI, and XII cranial nerves palsies. Computed tomography and magnetic resonance images are described. The lesion was locally aggressive and outcome was fatal. IMFT was identified by analysis of postmortem specimen with histopathologic and immunohistochemical confirmation. Discussion: IMFT can be locally destructive lesions. Involvement of the skull base and cervical spine is indistinguishable from an aggressive infection or a malignant tumor and can be fatal as in our case report. The difficulties in establishing clinicopathologic diagnosis, radiological imaging characteristics, and treatment are discussed.
    Skull Base Surgery 10/2008; 18(5):339-43. · 0.72 Impact Factor