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Biomedical subjects

R Ferrarese

Publications and source records attributed to R Ferrarese.

At least 19 recordsLinked to original sources
PubMed2006

Structure and function of the extraembryonic membrane persisting around the larvae of the parasitoid Toxoneuron nigriceps.

The embryo of Toxoneuron nigriceps (Hymenoptera, Braconidae) is surrounded by an extraembryonic membrane, which, at hatching, releases teratocytes and gives rise to a cell layer embedding the body of the 1st instar larva. This cell layer was studied at different developmental times, from soon after hatching up to the first larval moult, in order to elucidate its ultrastructural, immunocytochemical and physiological function. The persisting "larval serosa" shows a striking structural and functional complexity: it is a multifunctional barrier with protective properties, limits the passage of macromolecules and it is actively involved in the enzymatic processing and uptake of nutrients. The reported results emphasizes the important role that the embryo-derived host regulation factors may have in parasitism success in Hymenoptera koinobionts.

Animal Nutritional Physiological Phenomena↗
PubMed2001

Hirudo medicinalis: a new model for testing activators and inhibitors of angiogenesis.

An increasing body of evidence indicates that in the leech Hirudo medicinalis the angiogenic process is finely regulated and coordinated by the botryoidal tissue. In this paper we provide evidence on the involvement of botryoidal tissue cells in angiogenesis induced in H. medicinalis by a variety of stimuli including surgical wounds or the administration of modulators of neovascularization. Interestingly, we show that either human activators of vascular cell growth, or anti-angiogenic peptides like angiostatin and endostatin, or the drug mitomycin, can induce a prompt biological response in H. medicinalis. We show as well that angiogenesis in this invertebrate shares a surprising degree of similarity with neovascularization in vertebrates, both at the biochemical and cellular levels, because it involves similar growth factors/growth factor receptors, and relies on analogous cell-cell or cell-matrix interactions. For these reasons we suggest that H. medicinalis can be used as a reproducible model for testing activators or inhibitors of angiogenesis, and for investigating the biochemical, ultrastructural and cellular processes involved in new vessel formation.

Angiogenesis Inhibitors↗
PubMed1989

Ultracytochemical localization of guanylate cyclase in early human placenta.

Previous biochemical and cytochemical studies have indicated that in human term placenta the enzyme guanylate cyclase (GC) is associated mostly with the cytosolic fraction of homogenates and localized on the syncytiotrophoblast microvillous border. In the present study we have shown cytochemically the GC particulate form in early human placenta using guanylyl-imidodiphosphate [Gpp(NH)p] as substrate and NaN3 as activator. In samples of placental villi taken from the 6th to 12th week of pregnancy, the GC reaction product was always found on the apposing Langhans cytotrophoblast and syncytiotrophoblast plasma membranes. Furthermore, GC was present on cells in mitosis of the Langhans cytotrophoblast. From the 11th week GC was also visible on basal plasma membranes of Langhans cytotrophoblast and on endothelial cells of fetal capillaries. In samples of human term placenta GC was detectable on the syncytiotrophoblast microvillous border. This suggests a shift of enzyme localization during pregnancy.

Female↗
PubMed1988

Ultracytochemical localization of adenylate cyclase in early human placenta.

A cytochemical study was carried out on adenylate cyclase (AC) activity in the early human placenta. Samples of placental villi were incubated in a medium containing adenylyl-imidodiphosphate (AMP-PNP) as specific substrate. No AC reaction product was encountered in placenta villi taken at 5 and 7 weeks of pregnancy. AC activity appeared at 9 weeks. At 9 and 10 weeks, AC reaction product was localized on the basal plasma membranes and on apposed plasma membranes of the Langhans cytotrophoblast. At 11 weeks AC activity was also clearly visible on Langhans cytotrophoblast and syncytiotrophoblast apposed plasma membranes. No AC reaction product was ever detected on the syncytiotrophoblast microvillar membrane. These results are in agreement with biochemical studies that localize AC on the villous trophoblast plasma membranes associated with the fetal circulation.

Adenylyl Cyclases↗
PubMed1984

Phenotypic analysis of T cell subsets in the blood of chronically aborting women.

A relative decrease in helper and a parallel increase in suppressor-cytotoxic T lymphocytes was found in the blood of six habitually aborting women, as compared with the T-cell subset distribution in ten normal multiparae and eight multigravid post-partum women. It is suggested that an imbalance between the immunoregulatory T-cell subpopulations may contribute to the rejection of the semiallogenic fetus.

Abortion, Habitual↗
PubMed1979

A case of complete testicular feminisation and 47,XXY karyotype.

A very rare case of complete testicular feminisation with a 47,XXY sex chromosome complement is described. The X-chromatin is positive. The subject studied, who belongs to a family in which four other members have Morris's syndrome and have a 46,XY karyotype, is a perfect phenotypic female. The endocrine situation is unique and resembles, in part, that of subjects with Klinefelter's syndrome.

Adult↗