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Biomedical subjects

P Tenti

Publications and source records attributed to P Tenti.

46 records · Page 3Linked to original sources
PubMed1983

Pancreatic polypeptide (PP) cells in the PP-rich lobe of the human pancreas are identified ultrastructurally and immunocytochemically as F cells.

The ultrastructure of immunohistochemically identified PP cells has been investigated by applying the serial semithin/thin section technique to the human pancreas, with special reference to the posterior part of the head, reputed to originate from the ventral primordium. PP cells of this area differ from those already identified in the rest of the pancreas and correspond to a cell, not yet described in the human pancreas, characterized by larger granules of very variable shape and structure. Such granules resemble those of so-called "F cells", i.e. the PP cells of dog uncinate process and cat duodenal lobe, also coming from the ventral primordium. Thus, human "ventral lobe" PP cells have peculiar potentialities which are expressed in distinctive structural patterns of presently unknown functional meaning.

Fetus↗
PubMed1983

Merkel cell carcinoma of the skin: the structure and origin of normal Merkel cells.

A series of 15 Merkel cell tumours of skin is reported. They occur dominantly on the head and neck and on the extremities of elderly women, frequently presenting as a reddish nodule. Three cases were associated with squamous carcinoma at the same site, an association deserving further study. There are two main patterns: the commoner one takes the form of a trabecular carcinoma in the dermis mimicking metastatic carcinoma, including oat-cell carcinoma and neuroblastoma: a dissociated-cell form mimicks malignant lymphoma. The triad of vesicular nuclei with very small nucleoli, abundant mitotic activity and apoptosis is so characteristic as to be virtually pathognomonic in conjunction with structural features. Argyrophilia is common, but Bouin fixation is necessary to demonstrate it regularly. Small round secretory granules (89 +/- 18 nm) with narrow haloes, and an abundance of intermediate size filaments are among the ultrastructural hallmarks. There is a close similarity between better differentiated tumour cells and normal Merkel cells. The neural crest origin of MC is in doubt both on the basis of studies of the development and regeneration of MC and from the study of Merkel cell tumours.

Adenocarcinoma↗
PubMed1983

The endocrine cells of the chicken proventriculus.

The endocrine cells of the chicken proventriculus were investigated by selective staining techniques, immunohistochemistry and electron microscopy. The following endocrine cell types were identified: 1) Argyrophilic ECL-cells, of unknown function, were very numerous in the 21-day-old chick, but less numerous in the newborn chick; 2) somatostatin-producing D-cells; 3) GLI-cells producing glucagon-related peptides; 4) X-cells of unknown function; 5) BN-cells producing bombesin; and 6) relatively few 5-hydroxytryptamine-producing EC-cells. Each of these cell types show a distinct morphology, distribution and histochemical reactivity. With the exception of BN-cells, they resemble rather closely the corresponding endocrine cell types previously described in the oxyntic mucosa (EGL, D, X and EC cells) or in the intestinal mucosa (L-cells) of the mammalian gut.

Animals↗
PubMed1981

The diffuse endocrine-paracrine system of the gut in health and disease: ultrastructural features.

At least 16 types of endocrine-paracrine cells have been identified ultrastructurally in the gastrointestinal mucosa. The production of hormones and local messengers such as 5-hydroxytryptamine, gastrin, cholecystokinin, somatostatin, secretin, gastric inhibitory peptide (GIP), enteroglucagon (glicentin, GLI), motilin, neurotensin, substance P and the enkephalins, by these cells, has been established. Progress has also been made in cytological studies of gut and pancreatic endocrine tumours. Argentaffin EC cell carcinoids, gastrinomas (of several ultrastructurally different varieties of gastrin cells), L-cell tumours and D-cell tumours are among those cytologically and functionally defined in the gut. Functionally undefined tumours include the so-called non-argentaffin carcinoids arising in various parts of the gut, some of which have been characterised cytologically as gastric ECL cell tumours and gastroduodenal P-D1-cell tumours. Gastrinomas, vipomas and rare argentaffin carcinoids are among gut-related pancreatic endocrine tumours. Non-functional paragangliomas, usually with some neuromatous component, occur in the duodenal wall. Extrapancreatic vipomas display ultrastructural features of ganglioneuroblastomas with peptidergic granules.

Animals↗
PubMedDate not supplied

Primitive mucinous cystadenocarcinoma of the retroperitoneum. Case report and diagnostic considerations.

The combination of ultrasonography (US) and computed tomography (CT) proved useful in recognizing and defining the characteristics of a primitive mucinous cystadenocarcinoma of the retroperitoneum, a rare anatomopathological finding which consistently presents certain macroscopic features that help in the formulation of a diagnosis with imaging techniques.

Cystadenocarcinoma, Mucinous↗
PubMedDate not supplied

[Endometrial adenocarcinoma during the fertile age].

Adenocarcinoma of the endometrium in patients 45 years old or younger accounts for 3-8% of all endometrial cancers diagnosed. Ten women of age = 45 years treated for endometrial cancer stage I in our Clinic of Obstetrics and Gynaecology from December 1979 to December 1988. Two cases were nulliparae, none of the 10 patients had Polycystic ovary syndrome and only was obese. In 80% of these cases the presenting symptom was abnormal vaginal bleeding and one patient had coexisting ovarian neoplasia (endometrioid carcinoma). Atypical endometrial hyperplasia was diagnosed in only one case. None of the patients had metastases or capillary like spaces invasion. Our policy was to treat these patients by hysterectomy (Piver 1 or 2), bilateral salpingo-oophorectomy and selective pelvic lymphadenectomy. One patient received adjuvant postoperative radiation therapy (49.5 Gy). One women was submitted two years later to radical mastectomy for ductal carcinoma of the breast. Endometrial adenocarcinoma in premenopausal women is generally of favourable histotype, at early stage and low grade, with excellent prognosis. The problem of quality of life is therefore of utmost importance. After surgical castration 4 of our patients experienced discomfort and excessive weight gain. The implications of long-term estrogen deprivation in younger patients must be seriously considered against as the change of ovarian conservation of hormonal replacement therapy.

Adenocarcinoma↗