Observation of the spatial distribution of gravitationally bound quantum states of ultracold neutrons and its derivation using the Wigner function.

Ultracold neutrons (UCNs) can be bound by the potential of terrestrial gravity and a reflecting mirror. The wave function of the bound state has characteristic modulations. We carried out an experiment to observe the vertical distribution of the UCNs above such a mirror at the Institut Laue-Langevin in 2011. The observed modulation is in good agreement with that prediction by quantum mechanics using the Wigner function. The spatial resolution of the detector system is estimated to be 0.7 µm. This is the first observation of gravitationally bound states of UCNs with submicron spatial resolution.

Endoscopic treatment for early stage colorectal tumors: the comparison between EMR with small incision, simplified ESD, and ESD using the standard flush knife and the ball tipped flush knife.

BACKGROUND: Early stage colorectal tumors can be removed by endoscopic mucosal resection but larger such tumors (20 mm) may require piecemeal resection. Endoscopic submucosal dissection (ESD) using newly developed endo-knives has enabled en-block resection of lesions regardless of size and shape. However ESD for colorectal tumor is technically difficult. Therefore, we performed EMR with small incision (EMR with SI) for more reliable EMR, ESD with snaring (simplified ESD) and ESD using the standard Flush knife and the novel ball tipped Flush knife (Flush knife BT) for easier and safer colorectal ESD. AIMS: The aims of our study were (1) to compare the treatment results of the following 3 methods (EMR with SI/si-mplified ESD/ESD) for early stage colorectal tumors, and (2) to assess the performance of Flush knife BT in colorectal ESD. METHODS: We treated 24/44/468 colorectal tumors and examined the clinicopathological features and treatment results such as tumor size, resected specimen size, procedure time, en-bloc resection rate, complication rate. We also treated 58 colorectal tumors (LST-NG:20, LST-G:36, other:2) using standard Flush knife and 80 colorectal tumors (LST-NG:32, LSTG:44, other:2) using Flush knife BT, and examined the clinicopathological features and treatment results mentioned above and also the procedure speed. RESULT: The median tumor size (mm) (EMR with SI/ simplified EMR/ESD) was 20/17/30 (EMR with SI vs. simplified ESD: p = n.s, simplified ESD vs. ESD: p < 0.0001). The median resected specimen size (mm) was 22.5/26/41 (EMR with SI vs. simplified ESD: p = 0.0018, simplified ESD vs. ESD: p < 0.0001). The procedure time (min.) was 19/27/60 (EMR with SI vs. simplified ESD: p = n.s, simplified ESD vs. ESD: p < 0.0001) The en-block resection rate (%) was 83.3/90.9 /98.9. The complication rate (post-operative bleeding rate/perforation p=n.s). In the treatment results of ESD for LSTs by knives, there was no difference between standard Flush knife and Flush knife BT for clinicopathological features and treatment results (procedure time, complication rate and en bloc R0 resection rate). However, procedure speed (cm2/min.) of LST-G was significantly faster in the Flush knife BT than in standard Flush knife. (standard Flush knife: 0.21 vs. Flush knife BT: 0.27, p = 0.034). CONCLUSION: EMR with small incision (EMR with SI) and ESD with snaring (simplified ESD) are good option to fill the gap between EMR and ESD in the colorectum, and also considered to become the nice training for the introduction of ESD. Flush knife BT appears to improve procedure speed compared with standard Flush knife, especially for LST-G in colo-rectal ESD.

The performance of a novel ball-tipped Flush knife for endoscopic submucosal dissection: a case-control study.

BACKGROUND: Endoscopic submucosal dissection (ESD) using short needle knives is safe and effective, but bleeding is a problem due to low haemostatic capability. AIM: To assess the performance of a novel ball-tipped needle knife (Flush knife-BT) for ESD with particular emphasis on haemostasis. METHODS: A case-control study to compare the performance for ESD of 30 pairs of consecutive early gastrointestinal lesions (oesophagus: 12, stomach: 32, colorectum: 16) with standard Flush knife (F) vs. Flush knife-BT (BT). Primary outcome was efficacy of intraprocedure haemostasis. Secondary outcomes included procedure time, procedure speed (dividing procedure time into the area of resected specimen), en bloc resection rate and recurrence rate. RESULTS: Median intraoperative bleeding points and bleeding points requiring haemostatic forceps were smaller in the BT group than in the F group (4 vs. 8, P < 0.0001, 0 vs. 3, P < 0.0001). There was no difference between groups for procedure time; however, procedure speed was shorter in the BT group (P = 0.0078). En bloc and en bloc R0 resection rates were 100%, with no perforation or post-operative bleeding. No recurrence was observed in either group at follow-up 1 year postprocedure. CONCLUSIONS: Ball-tipped Flush knife (Flush knife-BT) appears to improve haemostatic efficacy and dissection speed compared with standard Flush knife.

Retrospective study of technical aspects and complications of endoscopic submucosal dissection for laterally spreading tumors of the colorectum.

BACKGROUND AND STUDY AIMS: Laterally spreading tumors - non granular type (LST-NG) are more often considered candidates for endoscopic submucosal dissection (ESD) than laterally spreading tumors - granular type (LST-G), because of their higher potential for submucosal invasion. However, ESD for LST-NG can be technically difficult. The aim of our study was to compare our ESD results for LST-NG and for LST-G. PATIENTS AND METHODS: Ninety-nine LST-NG and 169 LST-G measuring 20 mm in size or more were removed by ESD. We retrospectively evaluated the clinicopathological features of the tumors and treatment results (en bloc resection rate, procedure time and speed, rate of use of ancillary devices, and complication and recurrence rates). RESULTS: Histopathology revealed that there were more submucosally invasive lesions in the LST-NG than in the LST-G group (28 % vs. 9 %; P < 0.0001). The en bloc resection rate, en bloc R0 resection rate, and en bloc curative resection rate of LST-NG were similar to those of LST-G (LST-NG: 99 %, 98 %, and 88 %; LST-G: 99 %, 98 %, and 91 %). In LST-NG, the median procedure time tended to be longer (LST-NG: 69 min; LST-G: 60 min) and the median procedure speed was slower (LST-NG: 0.15 cm (2)/min; LST-G: 0.25 cm (2)/min; P < 0.0001). Use of ancillary devices was higher for LST-NG (38 % vs. 15 % for LST-G; P < 0.0001), as was the perforation rate (5.1 % vs. 0.6 % for LST-G; P = 0.027). No recurrence was seen in either group. CONCLUSIONS: ESD was an effective treatment method for both LST-NG and LST-G. However, the degree of technical difficulty appears higher for LST-NG than for LST-G lesions, as shown by the lower dissection speed and higher perforation rate. ESD for LST-NG should probably be performed by those with significant experience of colorectal ESD.

The Parker Flex-Tip tube for nasotracheal intubation: the influence on nasal mucosal trauma.

We tested our hypothesis that use of the Parker Flex-Tip tracheal tube could reduce the incidence of nasal mucosal trauma during nasotracheal intubation when compared with a conventional tip tracheal tube. One hundred and two patients, who were scheduled for elective oral surgery in which nasotracheal intubation was indicated to optimise the surgical approach, were recruited into this study. Either a Flex-Tip tracheal tube or a conventional tip tracheal tube was chosen randomly for each nasotracheal intubation. The incidence of epistaxis using the Flex-Tip tracheal tube (6 (11.8%)) was significantly lower than that with the conventional tip tracheal tube (18 (35.3%); p = 0.009). Nasal pain due to intubation, rated on a 100-mm visual analogue scale, was less intense with the Flex-Tip tracheal tube (median, (10th-90th percentile) 19 (12-28) mm compared with the conventional tip tracheal tube (30 (22-35) mm; p < 0.001). The Flex-Tip tracheal tube thus appeared to reduce the incidence of nasal mucosal trauma during nasotracheal intubation and the incidence of post-intubation nasal pain, compared with the conventional tip tracheal tube.

The results and limitations of endoscopic submucosal dissection for colorectal tumors.

In the colorectal tumor, the lesions suitable for the endoscopic treatment are those with no lymph node metastasis such as adenomas, intramucosal cancers, and minimally invasive submucosal cancer (invasion depth 1000 m, well and moderately differentiated type, no lymphovascular invasion). The new endOscopic technique, endoscopic submucosal dissection (ESD) enables en-bloc resection of the lesions regardless of their size and location. In order to perform ESD more easily, safely, and efficiently, we invented water jet short needle knives (Flush knife). Emitting a jet of water from the tip of a sheath enables submucosal local injection with a knife itself without replacement of operative instruments, which leads to efficient treatment. Especially, Flush knife is very effective for the lesions located at lower rectum and anal canal where there are many vessels. We treated a total of 361 colorectal lesions by ESD between June 2002 and July 2007, and en-block complete resection rate was 98.3 %. In 12 cases, "muscle retracting sign" was recognized. This sign is an index of the discontinuation of ESD, but it is impossible to diagnose preoperatively. The postoperative bleeding occurred in 0.8 % (3 cases: no blood transfusion is needed). The intraoperative perforation occurred in 1.9 % (6 cases: 5 cases were treated conservatively, 1 case was treated surgically) and the postoperative perforation occurred in 1 case (0.3%) treated surgically. ESD is the extremely effective treatment for the colorectal tumors and also is possible to be performed safely with the appropriate choice of the devices and strategy for dissection.

Measurements of cosmic-ray low-energy antiproton and proton spectra in a transient period of solar field reversal.

The energy spectra of cosmic-ray low-energy antiprotons ( *p's) and protons ( p's) have been measured by BESS in 1999 and 2000, during a period covering reversal at the solar magnetic field. Based on these measurements, a sudden increase of the *p/p flux ratio following the solar magnetic field reversal was observed, and it generally agrees with a drift model of the solar modulation.

Expression of fibroblast growth factor-2 in the nucleus ambiguus following recurrent laryngeal nerve injury in the rat.

OBJECTIVES: To examine fibroblast growth factor-2 (FGF-2) immunoreactivity in the nucleus ambiguus (NA) after three different recurrent laryngeal nerve (RLN) injuries. STUDY DESIGN: Immunohistochemical analysis of FGF-2. METHODS: Thirty adult rats underwent left-sided RLN crush (group A). The left RLN was transected in groups B (n = 30) and C (n = 30); in group C, both nerve stumps were covered with silicone caps. FGF-2 in the NA was assessed as the ratio of the positive areas on the left (operated [O]) and right (unoperated [U]) sides. The ratio (O/U) was measured 1, 3, 7, 14, and 28 days after the procedure. Three rats underwent left-sided RLN exposure and were killed 7 days later (control). RESULTS: Left-sided RLN paralysis occurred until day 28 in group A. In the control group, O/U was approximately 1. In group A, O/U was significantly elevated on day 7; in group B, on days 3, 7, and 14; and in group C, on day 3. O/U in group B was significantly greater than that in group A on days 14 and 28. Maximal FGF-2 immunoreactivity was significantly lower in group C than in groups A and B. CONCLUSIONS: We demonstrated elevated production of FGF-2 in the NA after RLN injury. This endogenous FGF-2 might contribute to preventing lesion-induced neuronal death. Blockage of axonal regeneration might suppress FGF-2 production in the NA. Further understanding of the roles of FGF-2 after RLN injury may contribute to the prevention of neuronal death and facilitation of axonal regeneration.

Precision measurement of cosmic-Ray antiproton spectrum

The energy spectrum of cosmic-ray antiprotons ( &pmacr;'s) has been measured in the range 0.18-3.56 GeV, based on 458 &pmacr;'s collected by BESS in a recent solar-minimum period. We have detected for the first time a characteristic peak at 2 GeV of &pmacr;'s originating from cosmic-ray interactions with the interstellar gas. The peak spectrum is reproduced by theoretical calculations, implying that the propagation models are basically correct and that different cosmic-ray species undergo a universal propagation. Future BESS data with still higher statistics will allow us to study the solar modulation and the propagation in detail and to search for primary &pmacr; components.

Three-dimensional endoscopic images of vocal fold paralysis by computed tomography.

OBJECTIVE: To describe characteristics of 3-dimensional (3-D) computed tomographic (CT) endoscopic images of the larynx in unilateral vocal fold paralysis and the changes of the paralyzed vocal fold after phonosurgery as indicated by 3-D CT endoscopy. SETTING: A university medical center. PATIENTS: Twelve consecutive patients with unilateral vocal fold paralysis who underwent helical CT examination. Five of them underwent the CT examination before and after phonosurgical treatment. INTERVENTIONS: Three patients underwent arytenoid adduction, and 2 underwent type 1 thyroplasty. MAIN OUTCOME MEASURES: "Sagging," defined as caudal displacement of the vocal fold; and "thinning," defined as a decrease in the vertical thickness of the vocal fold and expansion of the ventricle on the affected side, were evaluated. RESULTS: Excessive motion artifacts in one patient prevented detailed description of his 3-D images. Sagging and thinning of the vocal fold and expansion of the ventricle on the affected side were noted on 6, 11, and 8 occasions, respectively. Adduction or augmentation of the paralyzed vocal fold after phonosurgery was observed in 3-D CT endoscopic images when displayed with bony densities. CONCLUSIONS: The use of 3-D CT endoscopy enables description of 3-D characteristics of unilateral vocal fold paralysis and supplements stroboscopic findings. Furthermore, CT endoscopic images, when simultaneously displayed with bony densities, may help in evaluating the effects of phonosurgical treatment of the paralyzed vocal fold.

Three-dimensional endoscopic mode for observation of laryngeal structures by helical computed tomography.

We produced high-quality three-dimensional (3D) endoscopic images of the larynx using helical scanning computed tomography. Subjects included two normal volunteers and 10 patients: five with laryngeal cancer, four with unilateral recurrent laryngeal nerve (RLN) palsy, and one with atrophied vocal folds. Two vertically split hemilaryngeal images were displayed together with the oral and tracheal views. Although motion artifacts were seen in four patients, laryngeal structures including the vocal fold, ventricular fold, and ventricle were clearly identified in all subjects. In the patients with cancer, axial images showing the extent of the tumor in each patient provided more information than 3D endoscopic images. In the patients with RLN palsy and atrophied vocal fold, combination of 3D endoscopic and cross-sectional images offered more diagnostic information than axial images alone.