Biomedical subjects

G Paino

Publications and source records attributed to G Paino.

At least 19 recordsLinked to original sources

PubMed1991

Recent progress in vertebrate limb morphogenesis.

Morphogenesis of vertebrate limb, specifically that of the chick wing, has been recognized as a suitable model to study the cellular and molecular mechanisms of pattern formation. The importance of cellular inductive phenomena and the relevance of the processes such as cell division and cell death in the above model are discussed. These studies have revealed the retinoic acid (RA) and retinols as convincing candidates for vertebrate morphogens. The recent discovery that the RA receptors belong to the steroid hormone receptor superfamily might indicate the universality of the RA morphogen and might enlighten the possible mode of its action. Identification and characterization of the 1d locus genes associated with the mouse limb morphogenesis and the possible involvement of the homeobox proteins in chick wing development have opened new prospects in understanding the molecular mechanisms of vertebrate morphogenesis.

Animals↗

PubMed1991

[SEM study on the mucosa of the pre-stomach in Bubalus buffalus].

Morpho-structural features of pre-stomach mucosa in the first period of post-natal life in Bubalus buffalus have been studied by SEM. The rumen presents a well defined morpho-structural architecture from 10 to 100 days of life, while in reticulum and in omasum numerous morphological variations have been noticed. During the development, in fact, in these organs the establishment of a typical morphological pattern has been observed.

Animals↗

PubMed1990

Transplantation of Lewis lung carcinoma in mouse uterus.

Earlier studies have shown that pregnant and nonpregnant mammalian uteri respond differently to tumor cell invasion, colonization and metastasis, but the biological basis of such differential uterine response has not been clarified. In the present study we have investigated the role of the metastatic potential of the tumor in the differential response of different stages of mouse uteri, using a highly metastatic tumor. The results obtained were compared with earlier data obtained using low metastatic or nonmetastatic tumors. Lewis lung carcinoma (LLC) cells were infused nonsurgically into nonpregnant uteri of various estrus stages and into pregnant uteri on day 3 postcoitum. Response of the uteri and embryos was studied histologically on days 2, 5 and 18 posttreatment (p.t.). The embryonic development was severely inhibited resulting in extensive resorption. In the tumor cell-treated animals, despite an early and uniform invasion the patterns of tumor cell colonization and metastasis differed remarkably from the pregnant to nonpregnant uteri. On day 5 p.t. 66% of nonpregnant animals showed tumor cells in the endometrium and 40% had tumor metastasis in other organs. Though 40% of the pregnant animals had tumor cells in the uteri, none had metastasis in other organs. By day 18 p.t., despite the absence of tumor cells in the uteri, 75% of nonpregnant animals showed metastasis in lung and liver. In pregnant animals, tumor cells were seen neither in uteri nor in other organs studied. These results indicate the refractory nature of both the pregnant and nonpregnant mouse uteri to the survival and colonization of LLC cells, but the mechanisms by which the tumor cells are eliminated differ between these two types of uteri.

Animals↗

PubMed1989

The vascularization of the Bursa cloacalis (of Fabricius) in the duck.

The morphological and structural features of the vascular component of the bursa of Fabricius in the duck are described. By means of an intravasal perfusion of suitably colored neoprene Latex or Microscopaque, or a perfusion of Indian ink, it was possible to follow visually the routes of arteries, veins and the microcirculation; this last represents a major characteristic of the bursal follicle in the duck. The microcirculation has its origins in several roots arising from the follicular arterioles, which in the region of the cortex constitute an open vascular layer. From these pre-capillary arterioles, adjacent to the limiting layer between cortex and medulla, a dense capillary network is formed. With the aid of an electron microscope the presence of a cortico-medullary barrier of an epithelio-reticular nature was revealed; close to it there are the terminal branches of the intrafollicular network. The barrier appears to be structurally more compact than that of the cortical capillaries of the mammalian thymus.

Animals↗

PubMed1989

Chromogranin- and somatostatin-containing neuroendocrine cells in the porcine uterus. An immunocytochemical study.

Endocrine cells scattered in organic mucosae were defined "Neuroendocrine" (NE) cells because they constitute a section of the Diffuse Neuroendocrine System (DNES). Such cells have never been evidentiated in the normal endometrium. By means of histochemical and immunohistochemical techniques, NE cells, some of which contain the hormone somatostatin, are described in the glandular epithelium of the uterine horn in non-pregnant, non-castrated, young and adult sows. As is known, the uterine horn is the organ of pregnancy in the pig. The localization, distribution and morphology of the uterine NE and somatostatin-containing cells are reported and the importance of their function, in the pregnant and non-pregnant porcine uterus, is discussed.

Animals↗

PubMed1989

Invasion and metastasis of Lewis lung carcinoma in the mouse uterus.

Patterns of Lewis lung carcinoma (LLC) cell invasion, colonization and metastasis were studied in C57 mouse uteri. LLC cells (5 X 10(4) in 0.05 ml) were infused nonsurgically into nonpregnant and pregnant uteri, 3 days postcoitum. The fate of cells was studied histologically on days 2, 5 and 18 posttreatment (PT). Despite a large degeneration of LLC cells in the lumina of both the pregnant and nonpregnant mice, in 38% of these uteri, tumor cells had invaded the endometrium by day 2 PT. However, subsequent distribution of tumor cells differed remarkably between the pregnant and the nonpregnant uteri. By day 5 PT, in 66% of the nonpregnant mice, tumor cells were common in the endometrium and metastases in other organs were seen in 40% of the animals. But in the pregnant mice only 40% uteri showed tumor cells and no metastasis was recorded. On day 18 PT tumor cells were rare in the nonpregnant uteri, but significantly, 75% of those animals showed lung and liver metastases. In pregnant mice, tumor cells neither survived in the uteri nor metastasized to other organs. LLC cells, infused into nonpregnant uteri, promptly metastasized to lungs without colonizing the uteri: this unique system may provide insight into the effects of organ-specific host factors on the growth and metastatic potential of tumor cells.

Animals↗

PubMed1989

[Morphostructural features of the pleural lymphatic circulation in the pig].

The morphostructural features of the lymphatic circle of swine visceral pleura were investigated by means of vital dye injection in the pleural cavity. In the animals treated as mentioned previously it was possible to observe that in the visceral pleura the superficial lymphatic network had formed the very thick mesh, while the underlying pulmonary parenchyma was not interested. This behaviour lets us suppose that the drainage of the visceral pleura is mainly a direct one.

Animals↗

PubMed1988

Influence of mouse uterus on the metastatic patterns of tumour cells.

Metastatic patterns of fibrosarcoma (FS) and Lewis lung carcinoma (LLC) cells transplanted into mouse uteri of various reproductive stages, were investigated. Tumour cells were infused non-surgically into the lumen of 3-day post coitum pregnant uterus or into non-pregnant uterus of known estrus stage. The fate of these tumour cells was studied histologically on days 2, 5 and 10 post treatment. No significant difference in the metastatic patterns of the FS or the LLC cells was seen between the non-pregnant uteri of various estrus stages. FS cells in few cases of non-pregnant uteri displayed the tendency to migrate and grow outside the myometrium without colonizing in the endometrium, but in pregnant uteri they colonized within the endometrium. LLC cells in the non-pregnant uteri promptly metastasized to distant organs like liver and lung; but those in the pregnant uteri rarely metastasized to other organs. These observations imply that the metastatic patterns of uterine tumour might depend on both the physiological state of the uterus and the tumour cell type.

Animals↗

PubMed1987