Validation of a New Method for Quantifying In Vivo Murine Tumor Necrosis by Sonography

Abstract Background The purpose of this study was to evaluate the changes in canal volume after root canal preparation in vivo with 3 different single-file techniques (Reciproc-Blue®, WaveOne-Gold® and XP-EndoShaper®), with a new method using CBCT and 3D reconstruction. Methods In this prospective study, thirty human lower premolars from healthy patients were used, in which extraction was indicated for orthodontic reasons. All the teeth used were caries- and restoration-free with complete root development, without signs of periodontal disease or traumatic occlusion, and with only one straight canal (up to 25º curvature). Teeth were randomly divided into three different groups: Reciproc-Blue, WaveOne-Gold and XP-EndoShaper. CBCT scans before root canal preparation were used to create a 3D reconstruction with RHINOCEROS 5.0 software to assess the initial canal volume, and then compared with 3D reconstructions after canal preparation to measure the increase in canal volume. Student’s t test for paired data were used to determine statistically significant differences between the before and after canal volumes. Anova test was used to determine statistically significant differences in the percentage of canal volume increase between the groups and Tukey's post-hoc test were used to paired comparison. Results Reciproc-Blue showed the higher increase in canal volume, followed by WaveOne-Gold and XP-EndoShaper (p = 0.003). XP-EndoShaper did not show a statistically significant increase in canal volume after root canal preparation (p = 0.06). Conclusion With this model, Reciproc-Blue showed higher increase in root canal volume, followed by WaveOne-Gold, while XP-EndoShaper did not significantly increase root canal volume during preparation.

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Multiple effects of tumor necrosis factor on lipoprotein lipase in vivo.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)47576-x ◽

1987 ◽

Vol 262 (17) ◽

pp. 8390-8394 ◽

Cited By ~ 9

Author(s):

H Semb ◽

J Peterson ◽

J Tavernier ◽

T Olivecrona

Keyword(s):

Tumor Necrosis Factor ◽

Lipoprotein Lipase ◽

Tumor Necrosis ◽

Necrosis Factor

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A New Method to Measure Type I and III Collagen Synthesis in Human Skin In Vivo: Demonstration of Decreased Collagen Synthesis After Topical Glucocorticoid Treatment

Journal of Investigative Dermatology ◽

10.1111/1523-1747.ep12555884 ◽

1992 ◽

Vol 98 (2) ◽

pp. 220-225 ◽

Cited By ~ 64

Author(s):

Aarne Oikarinen ◽

Pekka Autio ◽

Urpo Kiistala ◽

Leila Risteli ◽

Juha Risteli

Keyword(s):

Human Skin ◽

Collagen Synthesis ◽

New Method ◽

Type I ◽

Glucocorticoid Treatment

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Transcription Factor AP-2α Is Preferentially Cleaved by Caspase 6 and Degraded by Proteasome during Tumor Necrosis Factor Alpha-Induced Apoptosis in Breast Cancer Cells

Molecular and Cellular Biology ◽

10.1128/mcb.21.15.4856-4867.2001 ◽

2001 ◽

Vol 21 (15) ◽

pp. 4856-4867 ◽

Cited By ~ 32

Author(s):

Okot Nyormoi ◽

Zhi Wang ◽

Dao Doan ◽

Maribelis Ruiz ◽

David McConkey ◽

...

Keyword(s):

Breast Cancer ◽

Breast Cancer Cells ◽

Tumor Necrosis ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Factor Alpha ◽

Caspase 6 ◽

Induced Apoptosis ◽

Necrosis Factor

ABSTRACT Several reports have linked activating protein 2α (AP-2α) to apoptosis, leading us to hypothesize that AP-2α is a substrate for caspases. We tested this hypothesis by examining the effects of tumor necrosis factor alpha (TNF-α) on the expression of AP-2 in breast cancer cells. Here, we provide evidence that TNF-α downregulates AP-2α and AP-2γ expression posttranscriptionally during TNF-α-induced apoptosis. Both a general caspase antagonist (zVADfmk) and a caspase 6-preferred antagonist (zVEIDfmk) inhibited TNF-α-induced apoptosis and AP-2α downregulation. In vivo tests showed that AP-2α was cleaved by caspases ahead of the DNA fragmentation phase of apoptosis. Recombinant caspase 6 cleaved AP-2α preferentially, although caspases 1 and 3 also cleaved it, albeit at 50-fold or higher concentrations. Activated caspase 6 was detected in TNF-α-treated cells, thus confirming its involvement in AP-2α cleavage. All three caspases cleaved AP-2α at asp19 of the sequence asp-arg-his-asp (DRHD19). Mutating D19 to A19abrogated AP-2α cleavage by all three caspases. TNF-α-induced cleavage of AP-2α in vivo led to AP-2α degradation and loss of DNA-binding activity, both of which were prevented by pretreatment with zVEIDfmk. AP-2α degradation but not cleavage was inhibited in vivo by PS-431 (a proteasome antagonist), suggesting that AP-2α is degraded subsequent to cleavage by caspase 6 or caspase 6-like enzymes. Cells transfected with green fluorescent protein-tagged mutant AP-2α are resistant to TNF-α-induced apoptosis, further demonstrating the link between caspase-mediated cleavage of AP-2α and apoptosis. This is the first report to demonstrate that degradation of AP-2α is a critical event in TNF-α-induced apoptosis. Since the DRHD sequence in vertebrate AP-2 is widely conserved, its cleavage by caspases may represent an important mechanism for regulating cell survival, proliferation, differentiation, and apoptosis.

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