96 research outputs found
Clinical Outcome of Laparoscopic Intersphincteric Resection Combined with Transanal Rectal Dissection for T3 Low Rectal Cancer in Patients with a Narrow Pelvis
Purpose. The purpose of this study was to analyze the safety and feasibility of laparoscopic intersphincteric resection (ISR) combined with transanal rectal dissection (TARD) for T3 low rectal cancer in a narrow pelvis. Methods. We studied 20 patients with a narrow pelvis of median body mass index 25.3 (16.9–31.2). Median observation period was 23.6 months (range 12.2–56.7). Results. Partial, subtotal, and total ISR was performed in 15, 1, and 4 patients, respectively. Median duration of TARD was 83 min (range 43–135). There were no major complications perioperatively or postoperatively. Surgical margins were histologically free of tumor cells in all patients, and there was no local recurrence. Excluding urgency, frequency of bowel movements, and incontinence status improved gradually after stoma closure. Conclusion. Laparoscopic ISR combined with TARD is technically feasible for selective T3 low rectal cancer in patients with a narrow pelvis
Discovery of Negative Superhumps during a Superoutburst of January 2011 in ER Ursae Majoris
We report on a discovery of "negative" superhumps during the 2011 January
superoutburst of ER UMa. During the superoutburst which started on 2011 January
16, we detected negative superhumps having a period of 0.062242(9) d, shorter
than the orbital period by 2.2%. No evidence of positive superhumps was
detected during this observation. This finding indicates that the disk
exhibited retrograde precession during this superoutburst, contrary to all
other known cases of superoutbursts. The duration of this superoutburst was
shorter than those of ordinary superoutbursts and the intervals of normal
outbursts were longer than ordinary ones. We suggest a possibility that such
unusual outburst properties are likely a result of the disk tilt, which is
supposed to be a cause of negative superhumps: the tilted disk could prevent
the disk from being filled with materials in the outmost region which is
supposed to be responsible for long-duration superoutbursts in ER UMa-type
dwarf novae. The discovery signifies the importance of the classical prograde
precession in sustaining long-duration superoutbursts. Furthermore, the
presence of pronounced negative superhumps in this system with a high
mass-transfer rate favors the hypothesis that hydrodynamical lift is the cause
of the disk tilt.Comment: 8 pages, 3 figures, Accepted for publication in PASJ Lette
大規模グラフに対するノードの枝刈りを用いたRankClus の高速化
DEIM Forum2019最終論文集:http://db-event.jpn.org/deim2019/post/papers.htmlに掲
Circumbinary MHD Accretion into Inspiraling Binary Black Holes
As 2 black holes bound to each other in a close binary approach merger their
inspiral time becomes shorter than the characteristic inflow time of
surrounding orbiting matter. Using an innovative technique in which we
represent the changing spacetime in the region occupied by the orbiting matter
with a 2.5PN approximation and the binary orbital evolution with 3.5PN, we have
simulated the MHD evolution of a circumbinary disk surrounding an equal-mass
non-spinning binary. Prior to the beginning of the inspiral, the structure of
the circumbinary disk is predicted well by extrapolation from Newtonian
results. The binary opens a low-density gap whose radius is roughly two binary
separations, and matter piles up at the outer edge of this gap as inflow is
retarded by torques exerted by the binary; nonetheless, the accretion rate is
diminished relative to its value at larger radius by only about a factor of 2.
During inspiral, the inner edge of the disk at first moves inward in
coordination with the shrinking binary, but as the orbital evolution
accelerates, the rate at which the inner edge moves toward smaller radii falls
behind the rate of binary compression. In this stage, the rate of angular
momentum transfer from the binary to the disk slows substantially, but the net
accretion rate decreases by only 10-20%. When the binary separation is tens of
gravitational radii, the rest-mass efficiency of disk radiation is a few
percent, suggesting that supermassive binary black holes in galactic nuclei
could be very luminous at this stage of their evolution. If the luminosity were
optically thin, it would be modulated at a frequency that is a beat between the
orbital frequency of the disk's surface density maximum and the binary orbital
frequency. However, a disk with sufficient surface density to be luminous
should also be optically thick; as a result, the periodic modulation may be
suppressed.Comment: 54 pages, color figures, submitted to the Astrophysical Journal, a
high resolution version and movies can be found at
http://ccrg.rit.edu/~scn/cmhdaiibh
ELF3 suppresses gallbladder cancer development through downregulation of the EREG/EGFR/mTOR complex 1 signalling pathway
The prognosis of gallbladder cancer (GBC) remains poor, and a better understanding of GBC molecular mechanisms is important. Genome sequencing of human GBC has demonstrated that loss-of-function mutations of E74-like ETS transcription factor 3 (ELF3) are frequently observed, with ELF3 considered to be a tumour suppressor in GBC. To clarify the underlying molecular mechanisms by which ELF3 suppresses GBC development, we performed in vivo analysis using a combination of autochthonous and allograft mouse models. We first evaluated the clinical significance of ELF3 expression in human GBC tissues and found that low ELF3 expression was associated with advanced clinical stage and deep tumour invasion. For in vivo analysis, we generated Pdx1-Cre; KrasG12D; Trp53R172H; Elf3f/f (KPCE) mice and Pdx1-Cre; KrasG12D; Trp53R172H; Elf3wt/wt (KPC) mice as a control and analysed their gallbladders histologically. KPCE mice developed larger papillary lesions in the gallbladder than those developed by KPC mice. Organoids established from the gallbladders of KPCE and KPC mice were analysed in vitro. RNA sequencing showed upregulated expression of epiregulin (Ereg) in KPCE organoids, and western blotting revealed that EGFR/mechanical targets of rapamycin complex 1 (mTORC1) were upregulated in KPCE organoids. In addition, ChIP assays on Elf3-overexpressing KPCE organoids showed that ELF3 directly regulated Ereg. Ereg deletion in KPCE organoids (using CRISPR/Cas9) induced EGFR/mTORC1 downregulation, indicating that ELF3 controlled EGFR/mTORC1 activity through regulation of Ereg expression. We also generated allograft mouse models using KPCE and KPC organoids and found that KPCE organoid allograft tumours exhibited poorly differentiated structures with mTORC1 upregulation and mesenchymal phenotype, which were suppressed by Ereg deletion. Furthermore, EGFR/mTORC1 inhibition suppressed cell proliferation and epithelial–mesenchymal transition in KPCE organoids. Our results suggest that ELF3 suppresses GBC development via downregulation of EREG/EGFR/mTORC1 signalling. EGFR/mTORC1 inhibition is a potential therapeutic option for GBC with ELF3 mutation. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland
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