细胞功能测定

Aggregating brain cell cultures are primary, three-dimensional cell cultures consisting of even-sized, spherical structures that are maintained in suspension by constant gyratory agitation. Because of the avidity of freshly dissociated embryonic cells to attach to their cou ...

Over the past few years, the view that little or no cell turnover or replacement takes place within the adult central nervous system (CNS) has changed dramatically. The adult brain of both rodents and primates has been shown to embody undifferentiated, mitotically active precursor cells that a ...

Over the past several years, neuroscientists have developed a considerable interest in a glial cell found only in the first cranial nerve. These glial cells, which are referred to as “olfactory ensheath-ing cells,” provide ensheathment for the unmyelinated axons of the olfactory nerve (Do ...

Several distinct stages of differentiation have been described for the oligodendroglial lineage in vitro (Gard and Pfeiffer, 1990; Gard et al., 1995). These include the actively proliferating bipolar or tripolar oligodendroglial precursor cell, characterized by the presence of G ...

In complex tissues such as the central nervous system, differentiation and functional activity often require temporally and spatially dynamic epigenetic cues that cannot be reproduced in dissociated cell cultures. Organotypic cultures and, among them, hippocampal slice cult ...

Surgical resections of selected human brain areas, to ameliorate intractable epilepsy, provide opportunities to isolate, maintain, and examine nonmalignant human neural cells in vitro. Because these specimens tend to be from patients of early adulthood or older, neurons do not survi ...

In vitro assays are important tools for investigating how the intricate network of neuronal connections is established during brain development. We have been using different in vitro systems to study the cellular strategies involved in the formation of neuronal projections between ...

The telomeric poly(ADP-ribose) polymerase (PARP), tankyrase 1, modulates the impact of telomerase inhibition on human cancer cells. Thus, overexpression of tankyrase 1 in telomerase-positive cancer cells confers resistance to telomerase inhibitors, such as MST-312, whereas ph ...

More than 85% of human cancers and over 70% of immortalized human cell lines have highly elevated telomerase activity. In contrast, telomerase activity is down-regulated in most human adult somatic cells, except stem cells and germ cells. These results are consistent with telomerase confe ...

Constitutive activation of the mitogen-activated protein (MAP) kinase signaling pathway by oncogenic stimulation is widespread in human cancers. With the recently demonstrated links between MAP kinase, histone phosphorylation, gene transcription factors, and hTERT gene p ...

Shortening of telomeres prevents cells from uncontrolled proliferation. Progressive telomere shortening occurs at each cell division until a critical telomeric length is reached. Telomerase expression is switched off after embryonic differentiation in most normal cells, ...

Genetic experiments using a dominant-negative form of human telomerase (DN-hTERT) demonstrated that telomerase inhibition can result in telomeric shortening followed by proliferation arrest and cell death by apoptosis. Neoplastic cells from telomerase RNA null (mTERC−/−) mi ...

Telomerase is central to cellular immortality and is a key component of most cancer cells although this enzyme is rarely expressed to significant levels in normal cells. Therefore, the inhibition of telomerase has garnered considerable attention as a possible anticancer approach. Ma ...

The knockdown of genes that are over-expressed in cancer, and function in tumor onset and/or progression, is an attractive tool to impair the growth of tumor cells. Synthetic nucleic acids such as antisense oligodeoxynucleotides (AS-ODNs) or small-interfering RNAs (siRNAs) were appli ...

The method of RNA interference (RNAi) is an easy means of knocking down a gene without having to generate knockout mutants, which may prove to be difficult and time consuming. RNAi is a naturally occurring process that involves targeting the mRNA of a gene by introducing RNAs that are complementary to ...

RNA interference (RNAi) is one of the most commonly used procedures for gene targeting in today’s cutting edge technology and has great potential for use in clinical therapy. Using a plasmid construct that exogenously expresses short-hairpin RNAs (shRNAs) targeting a desired gene trans ...

Human telomerase reverse transcriptase (hTERT) represents a universal tumor-associated antigen to activate specific immune response in cancer immune therapy. Peptides derived from hTERT are presented by major histocompatibility complex (MHC) class I alleles to T lymphocyt ...

RNA interference (RNAi) has recently emerged as a reliable tool for studying the effects of knocking down or ablating the expression of specific genes. It is hoped that progress made in the laboratory toward in vitro down regulation of gene expression may be carried over into the clinic for treatme ...

Telomeres are the protective structures at the end of eukaryotic chromosomes. Telomerase is a ribonucleoprotein that contains both an RNA and a protein component for the maintenance of telomere length. Telomerase activity is detected in the majority of malignant tumors, but not in normal ...

Telomerase, a ribonucleoprotein enzyme, is detected in the vast majority of cancers, including malignant gliomas, but not in most normal somatic cells. To inhibit telomerase function effectively, we have adopted the 2′,5′-oligoadenylate (2-5A) antisense system. 2-5A is a mediator of one p ...