Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although molecular alterations involved in the development of squamous cell carcinoma of the cervix have been extensively described, these genetic changes have not been as well characterized in the development of cervical adenocarcinoma. Twenty-seven paraffin-embedded adenocarcinomas of the cervix, including three cases of adenoma malignum, were analyzed for molecular alterations associated with other gynecologic malignancies. The presence of human papillomavirus (HPV) was assessed by polymerase chain reaction (PCR) using internally nested consensus primers. HPV types were identified by restriction endonuclease digestion of the PCR products, using DNA sequencing to confirm each digestion pattern. The presence of HPV was correlated with immunohistochemical expression of the p53 gene product, the presence of mutations in codon 12 of Ki-ras, and allelic deletion of markers associated with the development of other gynecologic carcinomas. HPV was identified in 16 (59%) of 27 cases, including type 18 in 7 tumors, type 16 in 7 tumors, and type 45 in 2 tumors. HPV types 16 and 45 were always identified in adjacent uninvolved cervical epithelium, but HPV type 18 was absent from the adjacent non-neoplastic epithelium in four of the seven positive cases. HPV was not identified in any of three cases of adenoma malignum. Diffuse immunohistochemical staining of the p53 gene product was present in only one (HPV-negative) tumor. A mutation in codon 12 of Ki-ras was observed in one endocervical adenocarcinoma (with an endometrioid pattern). Loss of heterozygosity was identified only for a marker on chromosome 6p in one mucinous endocervical carcinoma. Most endocervical adenocarcinomas lack molecular alterations characteristic of other histologically similar gynecologic malignancies, as well as those described in cervical squamous cell carcinomas.
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PMID:Analysis of human papillomavirus infection and molecular alterations in adenocarcinoma of the cervix. 1061 75

An exponential amplification strategy for ultrasensitive detection of microRNA (miRNA) in biological extracts is developed based on a cross-catalyst strand-displacement reaction (CC-SDR). Functionally, the system consists of one upstream circuit and two downstream circuits, each of which comprises a three-stranded substrate complex and a single-stranded fuel. Importantly, the exponential amplification process does not require a polymerase or a nicking endonuclease. The whole network is activated by a miRNA trigger in the upstream circuit, which regenerates the miRNA trigger to catalyze another new upstream circuit and release two specified DNA outputs to further act as catalysts of the two downstream circuits, respectively. During each cross-catalyst network, two "mimic trigger" DNA are generated, which in turn catalyze the upstream system. Finally, the exponentially produced luminol-reduced AuNPs (lumAuNPs) and fluorescein-tagged signals are sensitively read out in the form of luminol-H(2)O(2)-horseradish peroxide (HRP)-fluorescein chemiluminescence resonance energy transfer (CRET) triplex probes by employing magnetic nanoparticles to reduce high background, achieving a detection limit of let-7a miRNA as low as 0.68 fM. Moreover, the proposed strategy exhibits an excellent specificity to discriminate one-base differences among the let-7 miRNA family and is successfully applied in real sample assay: let-7a miRNA in total RNA samples extracted from human lung tissue, and let-7b miRNA from human lung cancer cells and cervical adenocarcinoma cells, respectively. To the best of our knowledge, this is the first study to use the chemiluminescence technique for miRNA detection, which can be expected to provide a new and ultrasensitive platform for amplified detection and subsequent analysis of miRNA.
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PMID:Exponential amplification for chemiluminescence resonance energy transfer detection of microRNA in real samples based on a cross-catalyst strand-displacement network. 2157 58