Biomedical subjects

N Campioni

Publications and source records attributed to N Campioni.

At least 19 recordsLinked to original sources

PubMed1991

Structure and expression of the nerve growth factor gene in Xenopus oocytes and embryos.

A large part of the coding portion of the Xenopus nerve growth factor (NGF) gene has been identified and cloned by the use of a chicken cDNA probe and its sequence has been determined. Comparison of the derived amino acid sequence of mature Xenopus NGF with that of other species showed a high conservation, whereas comparison of the prepropeptide showed large divergent regions alternated with short conserved regions. Expression of the NGF gene was examined during development of oocytes and embryos. Surprisingly, NGF mRNA was found in the oocyte; it is present in small previtellogenic as well as in fully grown oocytes. NGF mRNA, passed to the embryo at fertilization, is degraded before the gastrula stage and starts accumulating again around the stage of the neurula. The association of NGF mRNA with polysomes is indicative of NGF synthesis during oogenesis. In fact, by using antibodies against mouse NGF it was possible to reveal NGF molecules present as precursors. These molecules accumulate during oogenesis and are maintained in the embryos up to the blastula stage; a very faint band corresponding to a smaller size peptide is sometimes detected. A maternal role for the NGF can be proposed, although a possible activity of NGF in the oocyte cannot be ruled out.

Amino Acid Sequence↗

PubMed1991

Experimental changes in the amount of maternally stored ribosomes affect the translation efficiency of ribosomal protein mRNA in Xenopus embryo.

The amount of maternal free ribosomes in developing Xenopus embryos has been experimentally modified; an increase was obtained by microinjection of purified ribosomes into fertilized eggs, and a decrease was induced by treatment with a drug which reduces the amount of free ribosomes. The effect of this manipulation on the partition of the ribosomal protein mRNA (rp-mRNA) was analyzed during embryo development; it was observed that when ribosomes available for translation are in excess, polysome loading with rp-mRNA decreases. Conversely, when ribosomes are scarce, polysome loading of rp-mRNA increases. These experiments, which artificially stress events observed in the course of development, indicate that there is a relationship between the availability of ribosomes in the cells and the utilization of rp-mRNA for synthesis of ribosomal proteins, as already suggested by previous observations on r-protein synthesis during embryogenesis.

Animals↗

PubMed1989

Combinations of monoclonal antibodies can distinguish primary lung tumors from metastatic lung tumors sampled by fine needle aspiration biopsy.

Transthoracic fine needle aspiration (FNA) biopsies performed under computed tomography (CT) scan (CT-FNA) have greatly improved the cytodiagnosis of lung tumors. However, the distinction between a primary lesion and a metastatic lesion still may be difficult on the basis of morphologic criteria. To evaluate whether a selected panel of monoclonal antibodies (MoAb) to tumor-associated antigens (TAA) can improve the diagnostic potential of FNA, we have immunocytochemically analyzed 122 pulmonary CT-FNA. Whereas conventional cytology was capable of recognizing only the neoplastic nature of the lesions, the immunocytochemical diagnosis could identify the primary or metastatic nature of the pulmonary masses in 92.5% of the cases. The immunocytochemical findings were confirmed by clinical-histopathologic data. The current results demonstrate that the use of immunocytochemical methods can significantly improve the diagnostic accuracy of conventional cytology of lung masses.

Adult↗

PubMed1987

Ribosomal protein, histone and calmodulin mRNAs are differently regulated at the translational level during oogenesis of Xenopus laevis.

The localization of r-protein mRNA in subcellular compartments has been analysed. It was observed that the mRNA for a representative r-protein (L1) is diffuse in the cytoplasm, as shown by in situ hybridization experiments and that the distribution of rp-mRNA between polysomes and light mRNPs changes during oogenesis. In early oogenesis this mRNA is found mostly in subpolysomal fractions, whereas at the beginning of vitellogenesis (stage II) it becomes associated with polysomes where it remains in a constant amount at later stages. Histone and calmodulin mRNA, on the contrary, are mostly associated with non-polysomal fast-sedimenting particles throughout oogenesis. This suggests that the partition of different classes of mRNA between polysomes, light mRNP and heavy particles depends on their nature and might be determined by different requirements for these mRNAs during oogenesis.

Animals↗

PubMed1986

A proposed TNM classification for malignant primary liver tumours.

On the basis of 211 hepatic resections and reresections, a study was made to evaluate the possibility of compiling a checklist for primary liver tumours according to the TNM classification. This would aid the surgeon in planning therapy and provide a useful guide for prognosis and late results.

Humans↗

PubMed1986

Peritoneovenous shunt and neoplastic ascites: a 5-year experience report.

The cases of 42 patients with malignant ascites treated with a peritoneal venous shunt over a 5-year period are reviewed to establish the incidence of surgical and postsurgical complications. Although the yield of malignant cells found in the peripheral blood was increased after shunting, no new hematogenous metastases were observed after the operation. No evidence of disseminated intravascular coagulation was observed after shunt placement. While the shunt effectively relieved the discomfort due to abdominal distention and respiratory impairment, no restoration of cutaneous hypersensitivity was observed in the nine patients who were anergic prior to surgery. The median survival of patients with breast and gynecological cancer, after surgery, was significantly longer than the survival of patients with primary gastrointestinal neoplasma. In conclusion, peritoneal venous shunt appears to be an effective and safe method to improve the quality of life of patients with malignant ascites.

Ascites↗

PubMed1985

[The so-called multiple leiomyomatous hamartoma of the lung].

Explore the source record for details and available documents.

Female↗

PubMed1985

Our experience with resection of primary and secondary liver tumours.

The authors retrospectively analyse the results achieved in recent years by surgical treatment of 103 malignant primary or secondary liver cancers: (Three patients have been operated on twice at different times for recurrence.) 23 hepatic resections were performed for benign lesions. The operative mortality is very low, the incidence of postoperative complications is minimal, and the survival up to 8 years is rather satisfactory. In all cases we used Ton That Tung's surgical technique, that is, "finger fracture with intraparenchymal ligature of the vasculobiliary pedicles."

Carcinoma, Hepatocellular↗

PubMed1985

Ribosomal-protein synthesis is not autogenously regulated at the translational level in Xenopus laevis.

Whether ribosomal-protein synthesis in Xenopus laevis is autogenously controlled at the translational level as is known to occur in prokaryotes has been studied. For this purpose ribosomal (r) proteins were prepared from X. laevis ribosomal subunits and group fractionated by ion-exchange chromatography. They were then added to an in vitro translation system directed by an oocyte mRNA fraction which contains template activity for r proteins. The synthesized radioactive products were analyzed by 2D gel electrophoresis and compared with controls. Similarly in vivo experiments were performed by microinjection of the fractionated proteins into the cytoplasm of Xenopus oocytes followed by incubation with [35S]methionine for different times. In all the experiments no evident effect of r proteins on the translation of their own mRNA was observed.

Animals↗

PubMed1981

Messenger RNA for ribosomal proteins in dormant and developing Artemia salina embryos.

Ribosomal proteins from Artemia salina have been separated in a two-dimensional acrylamide gel system and assigned to the small and large ribosomal subunits. Poly(A)-containing RNA was prepared from dormant cysts and from polysomes of 30 min, 1 h, 5 h and 12 h embryos and hatching larvae. The mRNA from different stages was translated in a wheat-germ lysate and its template activity for ribosomal proteins was analyzed. It was observed that mRNA activity for ribosomal proteins is stored in the cytoplasm of dormant cysts and that it is found associated with polysomes of 30 min and of later stages.

Animals↗

PubMed1978

Template activity for histones of poly(A)-minus RNA fraction from different developmental stages of Artemia salina embryos.

Template activity for histones of RNA fractions derived from Artemia salina embryos at different developmental stages were measured in a Krebs ascites cell-free system. Appreciable amounts of acid-soluble polypeptides comigrating with Hela cell histone markers on acrylamide gel electrophoresis were detected only when RNA fractions from nauplii were used. Tryptic peptide analysis by high voltage electrophoresis of the translational products had a pattern qualitatively similar to that of in vivo labeled histone markers from Hela.

Animals↗

PubMed1977