97 research outputs found
Sensitization of TRPV1 by EP(1 )and IP reveals peripheral nociceptive mechanism of prostaglandins
Prostaglandin E(2 )(PGE(2)) and prostaglandin I(2 )(PGI(2)) are major inflammatory mediators that play important roles in pain sensation and hyperalgesia. The role of their receptors (EP and IP, respectively) in inflammation has been well documented, although the EP receptor subtypes involved in this process and the underlying cellular mechanisms remain to be elucidated. The capsaicin receptor TRPV1 is a nonselective cation channel expressed in sensory neurons and activated by various noxious stimuli. TRPV1 has been reported to be critical for inflammatory pain mediated through PKA- and PKC-dependent pathways. PGE(2 )or PGI(2)increased or sensitized TRPV1 responses through EP(1 )or IP receptors, respectively predominantly in a PKC-dependent manner in both HEK293 cells expressing TRPV1 and mouse DRG neurons. In the presence of PGE(2 )or PGI(2), the temperature threshold for TRPV1 activation was reduced below 35°C, so that temperatures near body temperature are sufficient to activate TRPV1. A PKA-dependent pathway was also involved in the potentiation of TRPV1 through EP(4 )and IP receptors upon exposure to PGE(2 )and PGI(2), respectively. Both PGE(2)-induced thermal hyperalgesia and inflammatory nociceptive responses were diminished in TRPV1-deficient mice and EP(1)-deficient mice. IP receptor involvement was also demonstrated using TRPV1-deficient mice and IP-deficient mice. Thus, the potentiation or sensitization of TRPV1 activity through EP(1 )or IP activation might be one important mechanism underlying the peripheral nociceptive actions of PGE(2 )or PGI(2)
E1A Activates Transcription of p73 and Noxa to Induce Apoptosis
p73, a member of the p53 family of proteins, transcriptionally activates a number of genes involved in the control of cell cycle and apoptosis. Overexpression of p73 was detected in a large number of primary head and neck cancers, and in the established cell lines examined, these all contained inactivating p53 mutations. The significance of p73 overexpression in the pathogenesis of head and neck cancer is currently unclear. We have shown that the expression of adenovirus 5 E1A in a panel of head and neck cancer cell lines induces apoptosis independently of their p53 status. In this study we examined the role of p73 and its transcriptional targets in E1A-mediated induction of apoptosis. E1A expression resulted in significant activation of the TAp73 promoter but had no effect on the alternative, DeltaNp73 promoter. E1A also increased expression of endogenous TAp73 mRNA and protein. E1A mutants lacking the p300- and/or pRB-binding sites showed reduced ability to activate the TAp73 promoter. Additionally, mutations in the E2F1-binding sites in the TAp73 promoter impaired activation by E1A. Importantly, expression of the 13S isoform of E1A substantially induced the p53 apoptotic target Noxa in several p53-deficient cancer cell lines. Our results indicate that E1A activation of p73 and the p53 apoptotic target Noxa can occur in the absence of a functional p53. This activation is likely to play a key role in the mechanism of p53-independent apoptosis induced by E1A in some cancers and may provide an avenue for future cancer therapies
Ferrocenylnaphthalene Diimide-Based Electrochemical Detection of Aberrant Methylation in hTERT Gene
Since aberrant methylation at CpG sites is linked to the silencing of tumor suppressor genes, DNA methylation analysis is important for cancer diagnosis. We developed ferrocenylnaphthalene diimide (FND), which has two ferrocenyl moieties at the substituent termini, as an electrochemical indicator for hybridized DNA duplexes. In this study, we attempted to detect aberrant methylation of human telomerase reverse transcriptase gene (hTERT), an efficient cancer marker, using FND-based hybridization coupled with electrochemical detection via a multi-electrode chip
Fluorescence-guided bone resection by using Visually Enhanced Lesion Scope in diffuse chronic sclerosingosteomyelitis of the mandible: clinical and pathological evaluation
Diffuse chronic sclerosingosteomyelitis (DCSO) is a refractory disease, becausethe etiology and pathogenesis remain poorly understood and to determine the border betweenunhealthy boneandhealthybone is difficult. However,
progressive inflammation, clinical symptoms and a high recurrence rate of DCSO were the reasons for surgical
treatment. We report a case of a 66-year old woman with DCSO of the right side of mandible who was treated with
hemimandibulectomy and simultaneous reconstruction by vascularized free fibula flap. After preoperative administration of minocycline for 1 month, the bone fluorescence was successfully monitored by using a Visually Enhanced Lesion Scope (VELscope®). Intraoperatively, we could determine the resection boundaries. We investigated
the clinical and histopathological findings. The fluorescence findings were well correlated with histopathological
findings. Using a VELscope®was handy and useful to determine the border between DCSO lesion andhealthybone.
The free fibula flap under the minocycline-derived bone fluorescence by using a VELscope®offered a good quality
of mandibular bone and the successful management of an advanced and refractory DCSO
A transmission electron microscopic study of LLCMK 2 cells infected with Japanese encephalitis virus
LLCMK2 cells infected with Japanese encephalitis virus were studied by transmission electron microscopy, with a special consideration on the nature of white round granules of 0.4-1.3 μm dIameter with a scanning electron microscope. Virus particles were detected in cytoplasmic vacuoles with smooth-surfaced membranes, in those with rough-surfaced membranes and also in the perinuclear space. Besides the virus-enclosing vacuolar structures many lipid droplets were observed in the cytoplasm of infected cells, although they were few in control non-infected cells. These droplets were supposed to correspond to the white granules observed by a scanning electron microscope
Improving Mathematics Lesson and Evaluation through Setting Inquiry Problem-Solving Activities
The purpose of this research is to make a theoretical framework for improving mathematics lesson and evaluation through setting inquiry problem-solving activities effectively in junior high and senior high mathematics lessons. To achieve this, we first carried out a questionnaire survey to capture how students perceive learning mathematics and, based on the results, made a framework incorporated these activities for lesson design and evaluation of student’s learning. Then, sample lesson conducted in a junior and senior high school based on the framework was analyzed to investigate its effectiveness and get some practical suggestions
Screening for Oral Cancer Using Electrochemical Telomerase Assay
Electrochemical telomerase assay (ECTA) developed by our group was evaluated in an oral cancer screening using exfoliated oral cells and tissues obtained from patients of oral cancer, mucosa associated disease, or healthy volunteers. Telomerase activity from ECTA is correlated with hTERT mRNA expression level using a real‐time PCR and was increasing in the following order: healthy volunteer group<mucosa associated disease group<oral cancer group. Sensitivity and specificity of ECTA were 88% and 72%, respectively when used 17% of the threshold value based on the receiver operating characteristic curve in ECTA data
Electrochemical telomerase assay for screening for oral cancer
Telomerase has long been known to be a marker for cancer. We have developed a new method of detecting it: the electrochemical telomerase assay (ECTA). We have previously confirmed that the assay is easier to do and more precise than the conventional telomeric repeat amplification protocol, which is currently the most widely used. Here we describe a pilot study made to establish a screening system for oral cancer using ECTA. We evaluated three types of clinical samples obtained from 44 patients with oral cancer and 26 healthy volunteers: exfoliated cells from the whole oral cavity, exfoliated cells from local lesions, and tissue from the lesion itself. The current increase ratio (Δi) obtained by ECTA was significantly higher in the oral cancer group for each type of sampling used. The threshold value for Δi was 19% when calculated by analysis of receiver-operating characteristic curves. Sensitivity and specificity values were 86% and 85% for cells from the oral cavity, 82% and 85% in cells from local lesions, and 95% and 92% in cells from the tumour itself, respectively. There were also no significant differences in sensitivity and specificity associated with age, size of tumour, site of lesion, or degree of malignancy. ECTA therefore seems to be a promising assay for screening for oral cancer
Oral Cancer Screening Based on Methylation Frequency Detection in hTERT Gene Using Electrochemical Hybridization Assay via a Multi‐electrode Chip Coupled with Ferrocenylnaphthalene Diimide
Ferrocenylnaphthalene diimide‐based electrochemical hybridization assay via a multi‐electrode chip was applied to detect the methylation frequency in the promoter region of human telomerase reverse transcriptase (hTERT) gene for clinical samples from tissues, local exfoliated oral cells from a lesion, or from entire oral cavity after their methylation specific PCRs. These methylation frequencies were increased with cancer progress as the following order: healthy volunteers, oral leukoplakia as precancerous lesion, and oral squamous cell carcinoma (OSCC). Operating characteristic analysis of the obtained current data doesn\u27t only give excellent discrimination ability of OSCC, but also of oral leukoplakia from healthy volunteers for all samples. Sensitivity and specificity was 95% and 90%, respectively, which is a comparable with methods in practical use
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