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A Bulfone

Publications and source records attributed to A Bulfone.

46 records · Page 3Linked to original sources
PubMed1993

Spatially restricted expression of Dlx-1, Dlx-2 (Tes-1), Gbx-2, and Wnt-3 in the embryonic day 12.5 mouse forebrain defines potential transverse and longitudinal segmental boundaries.

The expression patterns of four genes that are potential regulators of development were examined in the CNS of the embryonic day 12.5 mouse embryo. Three of the genes, Dlx-1, Dlx-2 (Tes-1), and Gbx-2, encode homeodomain-containing proteins, and one gene, Wnt-3, encodes a putative secreted differentiation factor. These genes are expressed in spatially restricted transverse and longitudinal domains in the embryonic neural tube, and are also differentially expressed within the wall of the neural tube. Dlx-1 and Dlx-2 are expressed in two separate regions of the forebrain in an identical pattern. The Gbx-2 gene is expressed in four domains, two of which share sharp boundaries with the domains of the Dlx genes. One boundary is in the basal telecephalon between deep and superficial strata of the medial ganglionic eminence; the other boundary is in the diencephalon at the zona limitans intrathalamica. The Wnt-3 gene is expressed in a dorsal longitudinal zone extending from the hindbrain into the diencephalon, where its expression terminates at the zona limitans intrathalamica. Reciprocal patterns of expression are found within the dorsal thalamus for the Gbx-2 and Wnt-3 genes. These findings are consistent with neuromeric theories of forebrain development, and based upon them we suggest a model for forebrain segmentation.

Animals↗
PubMed1992

Isolation and characterization of a library of cDNA clones that are preferentially expressed in the embryonic telencephalon.

In order to isolate genes involved in development of the mammalian telencephalon we employed an efficient cDNA library procedure. By subtracting an adult mouse telencephalic cDNA library from an embryonic day 15 (E15) mouse telencephalic cDNA library we generated two subtracted libraries (ES1 and ES2). We estimate that ES1 contains between 200 and 600 different cDNA clones, which approximates the number of genes that are preferentially expressed in the E15 telencephalon, compared to the adult telencephalon. Northern analysis of 20 different cDNA clones shows that 14 of these are expressed at least 5-fold more in the E15 telencephalon than the adult telencephalon. Limited sequencing of the 14 differentially expressed clones reveals that 10 have no significant identity to sequences in GenBank and EMBL databases, whereas the other 4 have significant sequence identity to vimentin, histone 3.3, topoisomerase I and the B2 repeat element. In situ hybridization using one of the differentially expressed cDNAs, TES-1, demonstrates that it is transiently expressed in the anlage of the basal ganglia. In situ hybridization with another differentially expressed cDNA clone, TES-4, shows that it is specifically expressed in differentiating cells of the neural axis with a distinctive rostral-caudal temporal pattern. These findings, and the methods that we have developed, provide a framework for future investigations of the genetic control of telencephalon development.

Animals↗
PubMed1991

Coexpression of platelet-derived growth factor (PDGF) B chain and PDGF B-type receptor in human gliomas.

In this study we analyzed the expression of mRNA for PDGF-B and PDGF B-type receptor (PDGFrecB) in 42 biopsy specimens from human astrocytic gliomas and other brain tumors. All gliomas expressed PDGF-B mRNA at higher levels than found in peritumoral and normal nervous tissues. Levels of PDGF-B transcripts correlated strongly with those of mRNA for glial fibrillary acidic protein. Thus, the production of PDGF-B mRNA may be attributed mainly to tumoral glial cells. PDGFrecB transcripts were found in 24 out of 29 gliomas, in agreement with the hypothesis of an autocrine growth stimulation in these tumors. Moreover, mean levels of PDGFrecB expression were higher in glioblastomas than in astrocytomas and over 30-fold higher in meningiomas than in gliomas. This suggests that in gliomas PDGFrecB can be expressed also by vascular elements, in agreement with the hypothesized existence of a paracrine mechanism that may be responsible for the endothelial hyperplasias.

Astrocytoma↗
PubMed1991

Isolation and characterization of a novel cDNA clone encoding a homeodomain that is developmentally regulated in the ventral forebrain.

A complementary DNA, Tes-1, of a novel homeodomain protein has been cloned, and its pattern of expression has been characterized. It is a structural homolog of Distal-less, a homeodomain-encoding gene in D. melanogaster. Its expression is developmentally regulated and is limited to structures in the head. Within the central nervous system of the midgestation mouse embryo, it is expressed exclusively in the ventral forebrain. It is likely that Tes-1 plays a regulatory role in the development of this complex neural structure.

Amino Acid Sequence↗
PubMed1986

Simultaneous and successive localization of two antigens in the same tissue section using 3,3'-diaminobenzidine and 1-naphthol basic dye.

We describe two procedures for the simultaneous and successive localization of two antigens in the same tissue section. In the simultaneous staining procedure, the first antigen was localized using 3,3'-diaminobenzidine (DAB), while the second antigen was stained using the 1-naphthol basic dye (1-NBD) method. The colour of the second antigen depended on the basic dye used, and no mixing of colours was observed when the two antigens were localized in different cells or structures. However, sequential double staining proved to be more convenient for the demonstration of two antigens in the same cell. In this procedure, the first antigen was stained using 1-NBD, and the interesting microscopic fields were photographed. The basic dye was then completely removed, and the second antigen was stained using DAB.

3,3'-Diaminobenzidine↗
PubMedDate not supplied

Oncogenes and growth factors in gliomas.

The activation of cellular proto-oncogenes is related to the genesis and progression of neoplasias. Protein growth factors and their cellular receptors have been identified as products of some proto-oncogenes. The role of epidermal growth factor receptor (EGFr) in gliomas is presented. The expression of mRNA for platelet-derived growth factor (PDGF) and PDGF B-type receptor (PDGF-rec-B) in gliomas is analyzed. Gliomas express "in vivo" PDGF.B and PDGF-rec-B mRNAs. PDGF.B mRNA levels correlate with GFAP mRNA and does not correlate with the degree of malignancy. This is in agreement with the hypothesis of an autocrine growth stimulation in gliomas. However some findings seem to indicate that in these tumors the PDGF-rec-B is preferentially expressed by vascular elements. Thus, also a paracrine loop for endothelial cell growth stimulation may be suggested in malignant gliomas.

Brain Neoplasms↗
PubMedDate not supplied

Preferential expression of the dbl proto-oncogene in some neuroectodermal tumors.

The dbl oncogene belongs to a unique class of human transforming genes. The dbl proto-oncogene is activated by substitution of the 5' portion of the gene with an unrelated human sequence. The proto-oncogene product is distributed between the soluble and membrane fractions of the cytoplasm and its function remains still unknown. In order to understand the biological role of dbl in human malignancies or during cell differentiation we have investigated the expression of the dbl oncogene in a wide number of human tumors of different embryological derivation. We found that dbl is preferentially expressed in a few neoplastic histiotypes of neuroectodermal origin. The transcript size of 5.3 Kb strongly suggests that the gene is not truncated in these tumors. These data, together with the information that the proto-oncogene has been found expressed in normal brain and adrenal medulla, indicate that dbl expression may be involved in cell differentiation of some tissues of neuroectodermic origin.

Gene Expression Regulation, Neoplastic↗
PubMedDate not supplied

[Position of the upper incisor after orthodontic therapy with Tweed philosophy and mechanics: statistical study of average incisal variations in 3 Angle dento-skeletal classes, with and without extraction].

The skeletal characteristics of dento-alveolar malocclusions condition the orthodontic therapy plane and produce typical and recurrent variables in the final shape in "Tweed occlusion". The study effects with templates made out of cephalometric average values of treatment in the different dental malocclusions, shows direction and amount of therapeutics correction. The behaviour of upper and lower incisors to achieve the normal occlusion is in relation with the characteristics of Angle's Class and with the necessity of therapeutics dental extractions.

Adolescent↗