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R Puxeddu

Publications and source records attributed to R Puxeddu.

26 records · Page 2Linked to original sources
PubMed1996

Metastatic neoplasms to the larynx: report of three cases.

Metastatic involvement of the larynx by distant malignancies is a rare event that can occur by hematogenous or lymphogenous spread through a retrograde or anterograde route. Only 143 cases of secondary laryngeal tumors have been reported in the literature. Metastases from cutaneous melanoma and renal carcinoma are the most common, whereas only sporadic cases stemming from lung and colon adenocarcinoma have been documented. The authors report a case of lung adenocarcinoma and two cases of colonic adenocarcinoma metastatic to the larynx and discuss the problems related to the pathogenesis, diagnosis, and management of secondary laryngeal neoplasms.

Adenocarcinoma↗
PubMed1995

The main excretory duct (Stensen's) of the human parotid gland: a transmission and scanning electron microscope study.

The epithelial cells of the human parotid main excretory duct (Stensen) were studied by transmission (TEM) and scanning (SEM) electron microscopy through a variety of procedures that allowed the visualization of their three-dimensional microanatomy. Stensen's duct in humans is lined, in its distal portion, with a pseudostratified epithelium with tall principal cells and smaller basal cells, while the epithelium becomes progressively stratified cylindrically toward the oral stoma. Goblet cells are scattered among the other epithelial cells. The principal cells exhibit, on their lateral surfaces, numerous flattened laminar folds probably involved in transporting processes. A well-developed smooth endoplasmic reticulum intermingled with mitochondria occupies the cellular apices. Some vesicles are recognized on the cytoplasmic surfaces of the apical and lateral plasmalemma when cytoplasmic organelles are removed. All these features are interpreted as being involved in the process of endocytosis. In both TEM and SEM, the principal cells show a relevant number of irregular apical protrusions that may represent a kind of apocrine secretion. Thus, with regard to function, the human Stensen's duct seems to modify the composition of saliva by processes of resorption and secretion, the latter coming from goblet cells as well. The basal cells have a surface microanatomy completely different from that of principal cells. They exhibit, in fact, only sparse microvillosities and smooth areas on their lateral aspect, while their stromal surface is greatly augmented by irregular thin ramified processes. The role of basal cells is also discussed.

Adult↗
PubMed1995

Atypical "reversed" paroxysmal positioning nystagmus in benign paroxysmal positional vertigo.

An atypical paroxysmal positioning nystagmus (PPNy), "reversed" in its directional components, is a rare finding in patients suffering from benign paroxysmal positioning vertigo (BPPV). It poses problems of pathophysiogenetic interpretation, differential diagnosis with a CNS lesion and therapeutic strategy. Such a finding was observed in 7 patients (out of a total of 450 BPPV) and took on the typical PPNy pattern after repeated diagnostic manoeuvres. These aspects are incompatible with the "heavy cupula" mechanism (cupulolithiasis) and are better explained by the presence of "free endolymph aggregates" (canalolithiasis) within the posterior semicircular canal (p.s.c). Moreover, canalolithiasis would also permit a more convincing interpretation of all the clinical findings observed in typical p.s.c.-BPPV.

Adult↗
PubMed1995

The intracellular structure of secretory and ductal epithelia of human major salivary glands. A scanning electron microscopic study.

The secretory and ductal cells of human salivary glands have been studied at Scanning Electron Microscopy (SEM) by our modification of the Aldehyde-Osmium-DMSO-Osmium (A-ODO) maceration method which enables the analytical study of human bioptical specimens. The most interesting results are those concerning the visualization of the cytoplasmic aspect of intercellular canaliculi of serous cells and of mitochondria of ductal cells. The canaliculi appear as elongated cylindrical structures fenestrated by holes correspohding to the bases of microvilli deprived of the cytoskeleton. Mitochondria of principal cells are longer and more complex than previously reported.

Adult↗
PubMed1994

Immunocytochemical localization of Lewis blood group antigens in human salivary glands.

We demonstrated the immunohistochemical distribution of Le-a and Le-b blood group antigens in human major and minor salivary glands at the ultrastructural level by applying a post-embedding immunogold staining method. In secretors' glands, a faint Le-a reactivity was found only in mucous droplets, whereas Le-b antigen was intensely stained in secretory granules of most mucous cells, in those of intercalated duct cells, in the pale granular matrix of some serous cells, and, when osmication was omitted, in cytoplasmatic vesicles and cell surfaces of striated ducts. In the submandibular gland of a non-secretor, Le-a antigen was considerably stained in mucous droplets, whereas Le-b reactivity was restricted to the striated duct cells. These results indicate that the secretor status affects the secretion of Lewis antigens by mucous, serous, and intercalated duct cells but not the presence of Le-b as a surface antigen in striated duct cells.

ABO Blood-Group System↗
PubMed1992

The myoepithelial and basal cells of ducts of human major salivary glands: a SEM study.

The cytoarchitecture and distribution of myoepithelial (mecs) and basal (bc) cells of intralobular (intercalated, striated) and interlobular (excretory) ducts of human major salivary glands were studied by SEM through a variety of maceration and microdissection techniques. Intercalated ducts are covered by mecs which, unlike the large stellate cells of acini, are spindle shaped. Small star shaped mecs are rarely observed even in the most distal striated ducts, while no such cells are seen in excretory ducts. Basal cells form a more or less continuous row of small, basally placed cells in excretory ducts. Sparse bc are occasionally present in proximal striated ducts as well. Following microdissection, bc exhibit a cup-shaped apex which embraces the convex base of principal cells. This configuration may explain why, in TEM, bc seem to possess lateral processes which may be mistaken for mecs processes. Moreover, the lateral surfaces of bc do not exhibit the complex system of plasmalemma folds typical of principal cells. The present study demonstrates that fusate mecs are present in intercalated ducts and that basal cells are distinct from myoepithelial cells. These results may have some relevance in histogenetic studies of salivary gland neoplasms.

Adolescent↗
PubMedDate not supplied

Surgical therapy of T1 and selected cases of T2 glottic carcinoma: cordectomy, horizontal glottectomy and CO2 laser endoscopic resection.

AIMS AND BACKGROUND: Among the different laryngeal neoplasms, glottic carcinoma is known to be one of the most suitable for functional management. Nevertheless, the best treatment for T1 and T2 glottic carcinoma, whether an open neck procedure, endoscopy or radiotherapy, with reference to recurrence, survival, and functional results, has long been debated. STUDY DESIGN: From February 1983 to September 1997, 83 patients with well to undifferentiated glottic carcinoma (48 pT1a, 14 pT1b, and 21 selected cases of pT2 with impairment of vocal cord mobility) were submitted to surgery at the Otorhinolaryngologic Section of the Department of Surgical Sciences and Organ Transplantations of Cagliari University. Surgical treatment included 30 laryngofissures with simple or enlarged cordectomy, 22 horizontal glottectomies and 31 endoscopic laser resections. A retrospective review of the records of the patients was performed in order to obtain a better understanding of the outcome of the three different surgical procedures in our institution. RESULTS: According to the Kaplan-Meier method, the probability of remaining free of local recurrence 3 years after primary surgery was 0.90 for the T1 group and 0.85 for the T2 group. The distribution of recurrences for cordectomy, glottectomy and CO2 laser at 3 years showed a cumulative probability of remaining free of disease after primary surgery of 0.86, 0.85 and 0.88. The probability of remaining free of local recurrence 3 years after salvage surgery was 0.96 for the T1 group and 0.95 for the T2 group. Analyzing the phenomena for type of surgical procedure, local control at 3 years after salvage surgery for cordectomy, glottectomy and exclusive CO2 laser was 0.93, 0.90 and 0.92, respectively. In the endoscopic group, local control rate after any type of salvage therapy modified the percentage at 3 years to 100%. Anterior commissure spread (AC1-AC2) resulted in a difference (not statistically significant) in local control between the group of patients without and with anterior commissure involvement. Laryngeal preservation was achieved in 93.7% (45/48) of patients who survived after salvage surgery following open neck procedures and in 100% of patients originally submitted to the endoscopic approach. CONCLUSIONS: In our experience, although open laryngeal procedures can be still considered a valid option in the treatment of T1 and selected cases of T2 glottic carcinoma, endoscopic laser excision offered an oncologically adequate alternative to the traditional techniques, with minimum discomfort for the patient and satisfactory preliminary functional results.

Adult↗