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Biomedical subjects

M Cavallaro

Publications and source records attributed to M Cavallaro.

8 recordsLinked to original sources

Generation of human cortical neurons from a new immortal fetal neural stem cell line.

Isolation and expansion of neural stem cells (NSCs) of human origin are crucial for successful development of cell therapy approaches in neurodegenerative diseases. Different epigenetic and genetic immortalization strategies have been established for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new, clonal NSC (hc-NSC) line, derived from human fetal cortical tissue, based on v-myc immortalization. Using immunocytochemistry, we show that these cells retain the characteristics of NSCs after more than 50 passages. Under proliferation conditions, when supplemented with epidermal and basic fibroblast growth factors, the hc-NSCs expressed neural stem/progenitor cell markers like nestin, vimentin and Sox2. When growth factors were withdrawn, proliferation and expression of v-myc and telomerase were dramatically reduced, and the hc-NSCs differentiated into glia and neurons (mostly glutamatergic and GABAergic, as well as tyrosine hydroxylase-positive, presumably dopaminergic neurons). RT-PCR analysis showed that the hc-NSCs retained expression of Pax6, Emx2 and Neurogenin2, which are genes associated with regionalization and cell commitment in cortical precursors during brain development. Our data indicate that this hc-NSC line could be useful for exploring the potential of human NSCs to replace dead or damaged cortical cells in animal models of acute and chronic neurodegenerative diseases. Taking advantage of its clonality and homogeneity, this cell line will also be a valuable experimental tool to study the regulatory role of intrinsic and extrinsic factors in human NSC biology.

Cell Differentiation↗

Unitubulotestis sardae (Trematoda: Didymozoidae) infection in Atlantic bonito Sarda sarda (Perciformes: Scomberomoridae) in the Ionian and Tyrrhenian Seas: histopathological and SEM investigations.

Nematobothrinae are trematoda digenea that usually live in cysts in fish tissues. They have been reported in different teleost species although the host-parasite relationships remain to be elucidated. This report is aimed at analysing the presence of Unitubulotestis sardae in the Atlantic bonito (Sarda sarda) populations fished in the Straits of Messina. The histopathological change reported in literature in similar cases is an aneurisma verminosa saccata, whereas, in the specimens here described, we show neovascularisation and at the same time, hyperplasia of the gill epithelium, leading to the formation of a bistratified cystic wall. The SEM examination of the parasitic cysts gave us a better understanding of the surface microanatomical details of the cystic walls. The external surface appeared to be constituted by a pluristratified covering epithelium of the gill arch. The internal layer was constituted by a net of blood vessels richly anastomosed with those originating from the gill arch arteries. This could be in agreement with data reported by Grabda (1947) on the localisation of the juvenile stages of the parasite in this blood vessel, but the evolution in cysts formation does not show similarities with the formation of an aneurisma.

Animals↗

Immunohistochemical localization of BDNF-, TrkB- and TrkA-like proteins in the teleost lateral line system.

The lateral line system, formed of both superficial (pit organs) and canal neuromasts, is one of the major mechanosensory systems in fish. It has always been assumed that this system depends on neurotrophins and their cognate Trk receptors for development and maintenance, as has been shown in other mechanosensitive systems of vertebrates. However, until nowthis issue has not been specifically addressed. In this study we used immunohistochemistry to investigate the occurrence and localization both of neurotrophins (NGF-, BDNF- and NT-3-like) and of Trk-like proteins (TrkA-, TrkB-, TrkC-like) in alevins of Salmo salar and S. trutta. All cells in the pit organs of S. salar displayed strong immunoreactivity for TrkB-like and BDNF-like, whereas they were restricted to the hair cells in S. trutta. The hair, supporting and mantle cells of S. salar, and the mantle cells of S. trutta, also expressed TrkA-like immunoreactivity. In the canal neuromasts BDNF-, TrkA- and TrkB-like proteins were present in all cells, without differences between species. NGF-, NT-3- and TrkC-like immunoreactivity were never detected. The present results suggest that mechanoreceptive hair cells, as well as supporting cells, in the lateral line system are under the control of the BDNF-TrkB-like complex, and probably of ligands of TrkA-like receptors.

Animals↗

Isolation and characterization of neural stem cells from the adult human olfactory bulb.

We have recently isolated stem cells deriving from the olfactory bulbs of adult patients undergoing particularly invasive neurosurgery. After improving our experimental conditions, we have now obtained neural stem cells according to clonal analysis. The cells can be expanded, established in continuous cell lines and differentiated into the three classical neuronal phenotypes (neurons, astrocytes, and oligodendrocytes). Also, after exposition to leukemia inhibitory factor, we are able to improve the number of neurons, an ideal biological source for transplantation in various neurodegenerative disorders.

Adult↗

Querying temporal clinical databases with different time granularities: the GCH-OSQL language.

There is a need for managing temporal clinical information given at different levels of granularity. Different time granularities are also needed in querying clinical databases. In this paper, we describe GCH-OSQL (Granular Clinical History--Object Structured Query Language), an object-oriented temporally-oriented extension of SQL. GCH-OSQL is based on an object-oriented temporal data model. It allows storage of clinical information at different and mixed granularities. GCH-OSQL deals with the valid time of clinical information. GCH-OSQL offers also a graphical user-interface. It guides different end users, from expert to naive, to formulate expressive and correct queries.

Computer Graphics↗

[Adaptation of peripheral microcirculation in the course of pregnancy].

The present prospective study investigates the changes of the peripheral microcirculation during pregnancy and puerperium, especially in preeclampsia. Using videocapillary microscopy we investigated 30 pregnant women at 4 different times. We studied red cell velocity as well as reactivity to artificial ischaemia of capillary blood vessels. An increase of red cell velocity during the course of pregnancy of approximately 30% and a reduction near normal values within 12 weeks after delivery was demonstrated. There is an obvious decrease of vascular reactivity to ischaemia as a consequence of increasing physiological vasodilatation in pregnancy. 24 pregnant pregnant women with normal peripheral microcirculation at the beginning of pregnancy had an uneventful pregnancy but 3 out of 6 pregnant women with an obviously impaired microcirculation developed pregnancy induced hypertension. These 3 were smokers.

Adult↗