Search results for "BLAST"
showing 10 items of 2136 documents
Netrins guide migration of distinct glial cells in the Drosophila embryo
2010
Development of the nervous system and establishment of complex neuronal networks require the concerted activity of different signalling events and guidance cues, which include Netrins and their receptors. In Drosophila, two Netrins are expressed during embryogenesis by cells of the ventral midline and serve as attractant or repellent cues for navigating axons. We asked whether glial cells, which are also motile, are guided by similar cues to axons, and analysed the influence of Netrins and their receptors on glial cell migration during embryonic development. We show that in Netrin mutants, two distinct populations of glial cells are affected: longitudinal glia (LG) fail to migrate medially …
Segment-specific requirements for dorsoventral patterning genes during early brain development in Drosophila.
2006
An initial step in the development of the Drosophila central nervous system is the delamination of a stereotype population of neural stem cells (neuroblasts, NBs) from the neuroectoderm. Expression of the columnar genes ventral nervous system defective (vnd), intermediate neuroblasts defective (ind) and muscle segment homeobox (msh) subdivides the truncal neuroectoderm(primordium of the ventral nerve cord) into a ventral, intermediate and dorsal longitudinal domain, and has been shown to play a key role in the formation and/or specification of corresponding NBs. In the procephalic neuroectoderm(pNE, primordium of the brain), expression of columnar genes is highly complex and dynamic, and th…
Emerging Therapeutic Strategies for Traumatic Spinal Cord Injury
2020
Spinal cord injury (SCI) is a debilitating neurologic condition with tremendous socioeconomic impact on affected individuals and the health care system. The treatment of SCI principally includes surgical treatment and marginal pharmacologic and rehabilitation therapies targeting secondary events with minor clinical improvements. This unsuccessful result mainly reflects the complexity of SCI pathophysiology and the diverse biochemical and physiologic changes that occur in the injured spinal cord. Once the nervous system is injured, cascades of cellular and molecular events are triggered at varying times. Although the cascade of tissue reactions and cell injury develops over a period of days …
Oligosaccharide and Ganglioside Neuraminidase Activities of Mucolipidosis I (Sialidosis) and Mucolipidosis II (I-Cell Disease) Fibroblasts
1979
Fibroblasts cultured from the skin of patients with the genetic diseases mucolipidosis I and mucolipidosis II were found deficient in a neuraminidase specific for both an α23 and and α2 6 type of neuraminosyl linkage of sialyl oligosaccharides. Obligate heterozygotes (parents) showed an intermediate activity in mucolipidosis I, but a normal one in mucolipidosis II. The neuraminidase activity of mucolipidosis I fibroblasts towards gangliosides, measured at pH 4.5 in the presence of Triton X-100, was within the range of normal controls with gangliosides Gm3 and GD3, but somewhat diminished with a bovine brain ganglioside preparation. In mucolipidosis II, neuraminidase activity was markedly de…
Investigating the Role of Guanosine on Human Neuroblastoma Cell Differentiation and the Underlying Molecular Mechanisms
2021
Neuroblastoma arises from neural crest cell precursors failing to complete the process of differentiation. Thus, agents helping tumor cells to differentiate into normal cells can represent a valid therapeutic strategy. Here, we evaluated whether guanosine (GUO), a natural purine nucleoside, which is able to induce differentiation of many cell types, may cause the differentiation of human neuroblastoma SH-SY5Y cells and the molecular mechanisms involved. We found that GUO, added to the cell culture medium, promoted neuron-like cell differentiation in a time- and concentration-dependent manner. This effect was mainly due to an extracellular GUO action since nucleoside transporter inhibitors r…
Early steps in building the insect brain: neuroblast formation and segmental patterning in the developing brain of different insect species
2003
In insects, morphological, molecular and genetic studies have provided a detailed insight into the ontogenetic processes that shape the ventral nerve cord. On the other hand, owing to its complexity and less obvious segmental composition, the knowledge about the development of the brain is still fragmentary. A promising approach towards gaining insight into fundamental processes underlying brain development is the comparison of embryonic brain development among different insect species. However, so far such comparative analyses are scarce. In this review, we summarize and compare data on the early steps in brain formation in different hemi- and holometabolous insects. We show that basic asp…
Abstract 448: Molecular analysis of BRAF gene and PTEN gene expression in metastatic colorectal cancer patients: Feasibility study
2014
Abstract Introduction There are numerous causes triggering CRC. 25-80% of CRC shown a deregulation in Epidermal Growth Factor Receptor (EGFR) pathway. Two signaling pathways downstream of the EGFR are dysregulated in CRC the mitogen-activated protein kinase (MAPK) and the phosphoinositide-3-kinase (PI3K) pathway. Activating mutations in KRAS and BRAF (MAPK pathway) and PIK3CA affect prognosis and/or response to anti-EGFR MoAb. PTEN is a downstream effector of EGFR pathway and is involved in PI3K pathway. Loss of PTEN protein expression can occur through epigenetic silencing and mutation or allelic loss. Immunohistochemistry (IHC) is the most effective way to assay for loss of PTEN expressio…
The Mutational Landscape of Acute Myeloid Leukaemia Predicts Responses and Outcomes in Elderly Patients from the PETHEMA-FLUGAZA Phase 3 Clinical Tri…
2021
This article belongs to the Collection The Biomarkers for the Diagnosis and Prognosis in Cancer.
Updated analysis of KRAS/NRAS and BRAF mutations in study 20050181 of panitumumab (pmab) plus FOLFIRI for second-line treatment (tx) of metastatic co…
2014
3568 Background: Previously, extended RAS analysis from this study showed a trend toward improvements in HR on OS and PFS with pmab + FOLFIRI vs FOLFIRI in WT RAS group vs WT KRAS exon 2 group. Her...
Analysis of KRAS , NRAS , BRAF , PIK3CA and TP53 mutations in a large prospective series of locally advanced rectal cancer patients
2019
Little information is available on the clinical significance of cancer-related genes such as KRAS, NRAS, BRAF, PIK3CA and TP53 in nonmetastatic rectal cancer. We investigated mutations of these genes in a large prospective series of locally advanced rectal cancer (LARC) patients who were recruited into two phase II trials. Mutational analyses were performed with diagnostically validated methods including polymerase chain reaction, capillary electrophoresis single-strand conformational analysis, Sanger sequencing and next-generation sequencing. Associations between single or multiple gene mutations and clinicopathological characteristics and treatment outcomes were explored. Of these 269, 21…