Cell adhesion and actin dynamics factors promote axonal extension and synapse formation in transplanted Drosophila photoreceptor cells

Vision is formed by the transmission of light stimuli to the brain through axons extending from photoreceptor cells. Damage to these axons leads to loss of vision. Despite research on neural circuit regeneration through transplantation, achieving precise axon projection remains challenging. To achieve optic nerve regeneration by transplantation, we employed the Drosophila visual system. We previously established a transplantation method for Drosophila utilizing photoreceptor precursor cells extracted from the eye disc. However, little axonal elongation of transplanted cells into the brain, the lamina, was observed. We verified axonal elongation to the lamina by modifying the selection process for transplanted cells. Moreover, we focused on N-cadherin (Ncad), a cell adhesion factor, and Twinstar (Tsr), which has been shown to promote actin reorganization and induce axon elongation in damaged nerves. Overexpression of Ncad and tsr promoted axon elongation to the lamina, along with presynaptic structure formation in the elongating axons. Furthermore, overexpression of Neurexin-1 (Nrx-1), encoding a protein identified as a synaptic organizer, was found to not only promote presynapse formation but also enhance axon elongation. By introducing Ncad, tsr, and Nrx-1, we not only successfully achieved axonal projection of transplanted cells to the brain beyond the retina, but also confirmed the projection of transplanted cells into a deeper ganglion, the medulla. The present study offers valuable insights to realize regeneration through transplantation in a more complex nervous system.

Effect of pre-hospital advanced airway management for out-of-hospital cardiac arrest caused by respiratory disease: a propensity score-matched study

Optimal pre-hospital care for out-of-hospital cardiac arrest (OHCA) caused by respiratory disease may differ from that for OHCA associated with other aetiologies, especially with respect to respiratory management. We aimed to investigate whether pre-hospital advanced airway management (AAM) was associated with favourable outcomes after OHCA caused by intrinsic respiratory disease. This nationwide, population-based, propensity score-matched study of adult patients in Japan with OHCA due to respiratory disease from 1 January 2005 to 31 December 2012 compared patients with and without pre-hospital AAM. The primary outcome was neurologically favourable survival at one month after the OHCA. Of 49,534 eligible patients, 20,458 received pre-hospital AAM and 29,076 did not. In a propensity score-matched cohort (18,483 versus 18,483 patients), the odds of neurologically favourable survival were significantly lower for patients receiving pre-hospital AAM (0.6% versus 1.5%; odds ratio [OR] 0.42 [95% confidence interval {CI} 0.34 to 0.52]). The results from multivariable logistic regression analysis also showed that pre-hospital AAM was significantly associated with a decreased chance of neurologically favourable survival (adjusted OR 0.43 [95% CI 0.35 to 0.52]). Similar findings were observed for one-month survival and pre-hospital return of spontaneous circulation. In subgroup analyses, pre-hospital AAM was associated with poor neurological outcomes, regardless of the type of airway device used (laryngeal mask airway, adjusted OR 0.35 [95% CI 0.19 to 0.57]; oesophageal obturator airway, adjusted OR 0.44 [95% CI 0.35 to 0.55]; and endotracheal tube, adjusted OR 0.47 [95% CI 0.30 to 0.69]). In conclusion, pre-hospital AAM was associated with poor neurological outcome among patients with OHCA caused by intrinsic respiratory disease.

Novel diagnostic and therapeutic techniques for surveillance of dysplasia in patients with inflammatory bowel disease

The risk for developing dysplasia and colorectal cancer in patients with longstanding inflammatory bowel disease (IBD) involving the colon is well documented. Random biopsies during white-light, standard-definition colonoscopy (33 to 50 biopsies) with or without dye spraying chromoendoscopy has been the recommended strategy in North America to detect dysplastic lesions in IBD. However, there are several limitations to this approach including poor physician adherence, poor sensitivity, increased procedure time and considerable cost. The new generation of high-definition endoscopes with electronic filter technology provide an opportunity to visualize colonic mucosal and vascular patterns in minute detail, and to identify subtle flat, multifocal, polypoid and pseudopolypoid neoplastic and non-neoplastic lesions. The application of these new technologies in IBD is slowly being adopted in clinical practice. In addition, the advent of confocal laser endomicroscopy provides an opportunity to explore real-time histology, thus redefining the understanding and characterization of the lesions in IBD. There is emerging evidence that serrated adenomas are also associated with longstanding IBD colitis and may be recognized as another important contributing factor to colorectal cancer development. The circumscribed neoplastic lesions can be treated using endoscopic therapeutic management such as mucosal resection or, especially, endoscopic submucosal dissection. This may replace panproctocolectomy in selected patients. The authors review the potential of these techniques to transform endoscopic diagnosis and therapeutic management of dysplasia in IBD.

[Single centre experience of endoscopic submucosal dissection (ESD) in premalignant and malignant gastrointestinal neoplasia]

INTRODUCTION

Worldwide endoscopic submucosal dissection (ESD) of early GI cancers or premalignant neoplasia is becoming increasingly important. In Germany ESD is restricted to larger endoscopic institutions and only a few literature reports are available. The aim of the present study is to describe the results of 46 ESDs conducted in a German endoscopic centre.

MATERIAL AND METHODS

Between June 2007 and May 2012 46 ESDs in 45 patients (33 men, 12 women, mean age 66.1 years) were performed in the oesophagus (n = 17), stomach (n = 23) and rectum (n = 6). Data were collected for the en-bloc, R0 and R0 en-bloc resection rates as well as for complications, the curative resection and the local recurrence rates. In order to demonstrate a learning curve, results were evaluated for two periods (June 2007 to November 2010 vs. December 2010 to May 2012).

RESULTS

ESD was technically possible in 93.5%. En-bloc, R0, R0 en-bloc and curative resection rates were 90.7%, 74.4%, 67.4% and 65.1%, respectively. The complication rate was 13%. In the second period en-bloc and R0 en-bloc resection rates increased from 81% to 100% and, respectively, from 52.4% to 81.8%. After a medium follow-up of 11.4 months, local tumour recurrence occurred in 10%. In cases of curative R0 en bloc resection of malignant tumours no tumour recurrence occurred.

DISCUSSION

Despite the small number of patients, the present data underline the value of ESD, especially in cases of R0 en-bloc resections in the therapy for premalignant and early malignant GI tumours. Due to the required learning curve, ESD should be restricted to larger endoscopic centres in Germany.

Esophageal submucosal dissection under steady pressure automatically controlled endoscopy (SPACE): a randomized preclinical trial

BACKGROUND AND STUDY AIMS

A new overtube system has been developed for steady pressure automatically controlled endoscopy (SPACE) in the gastrointestinal tract. The objectives of this study were to validate the feasibility and safety of SPACE in the esophagus, and to evaluate its potential advantages over conventional (manually insufflating) endoscopy in endoscopic submucosal dissection (ESD).

METHODS

This was a multicenter preclinical trial using acute porcine models (n = 20). In Experiment 1 (feasibility/safety study), SPACE was attempted in the esophagus with continuous monitoring of cardiopulmonary parameters and intraluminal pressures in the downstream bowel. Different insufflation pressures were tested to optimize the insufflation condition. Each session was video-recorded and scored by blinded reviewers. In Experiment 2 (randomized trial), esophageal ESD was attempted using either SPACE or conventional endoscopy, and results were compared.

RESULTS

In Experiment 1, SPACE was performed safely without intraluminal pressure elevation in the downstream bowel. According to video review, SPACE provided more stable, reproducible, and rapid visualization than conventional endoscopy. The insufflation pressure was optimized at 14 mmHg for esophageal SPACE. In Experiment 2, ESD was completed in all animals. The ESD time was significantly shorter with SPACE compared with conventional endoscopy (1326 vs. 1616 seconds; P = 0.009). Responses to questionnaires showed that 94 % - 100 % of participants considered SPACE to provide improved exposure and more uniform tissue tension than conventional endoscopy. Other data were comparable.

CONCLUSIONS

SPACE is feasible, safe, and potentially effective for complicated endoscopic procedures, such as ESD. SPACE improves and standardizes endoscopic exposure and tissue tension. A clinical study is required to further confirm its safety and clinical effectiveness.

Quantitative analysis of changes in blood concentrations and 'presumed effect-site concentration' of sevoflurane during one-lung ventilation

During one-lung ventilation, ventilation-perfusion mismatch decreases the arterial concentration of inhaled anaesthetics due to the arterial-to-venous concentration difference. This study tested the hypothesis that in humans, the 'presumed effect-site concentration' (taken as the mid-point between the arterial and superior jugular venous concentrations) of inhaled anaesthetic falls during one-lung (vs two-lung) ventilation. Four patients scheduled for elective prostatectomy (two-lung ventilation) and four patients for elective thoracotomy (one-lung ventilation) were randomly selected and assigned to receive sevoflurane (vaporiser-dial setting, 1.5%). Sevoflurane concentrations were measured periodically from radial artery and superior jugular vein (via a catheter advanced cephalad from the jugular vein). During one-lung ventilation, the end-expiratory sevoflurane concentration was stable at ∼1.3% but the mean (SD) presumed effect-site concentration declined initially from 58 (6.7) to 43 (4.7) μg.ml(-1) (p=0.011) before slowly recovering. A period of insufficient depth of anaesthesia is thus a risk during one-lung ventilation.

Clinical advantage of endoscopic submucosal dissection over endoscopic mucosal resection for early mesopharyngeal and hypopharyngeal cancers

BACKGROUND AND STUDY AIMS

In previous series, endoscopic mucosal resection (EMR) has been used for the treatment of early-stage mesopharyngeal and hypopharyngeal cancers to preserve patients' quality of life. Endoscopic submucosal dissection (ESD) offers potential advantages in comparison to EMR. So the aim of this retrospective study was to assess the utility of ESD compared with EMR for early-stage cancers of the meso- and hypopharynx.

PATIENTS AND METHODS

We studied 56 patients with 69 lesions who underwent either EMR or ESD between April 2001 and December 2008. EMR was performed until January 2007, and ESD was performed from February 2007 onward. We evaluated the en bloc resection rate, R0 resection rate, and treatment-related complications as short-term outcomes. Local recurrence, lymph node metastasis, and disease-related deaths were compared to evaluate long-term outcomes.

RESULTS

The en bloc and R0 resection rates were respectively 98 % and 79 % in the ESD group and 37 % and 26 % in the EMR group. There were no cases of treatment-related complications in the EMR group, but postoperative subcutaneous emphysema was observed in two patients in the ESD group. In the EMR group, one patient developed a local recurrence and one developed metastasis to the cervical lymph node and died of primary cancer.

CONCLUSIONS

ESD is a useful method of treatment for early mesopharyngeal and hypopharyngeal cancers and may be superior to EMR.

An autopsy report on multiple system atrophy diagnosed immunohistochemically despite severe ischaemic damage: a new approach for investigation of medical practice associated deaths in Japan

A 60-year old man with a 10-year history of multiple system atrophy (MSA) was found in respiratory arrest. After 4 months of respiratory support with two episodes of septic shock, he died. Autopsy disclosed severe atrophy of the mesencephalon, brainstem, medulla oblongata and cerebellum. Gallyas–Braak, α-synuclein and ubiquitin-positive inclusions in the cytoplasm of glial cells were evident, despite the severe ischaemic damage due to respiratory arrest and subsequent respiratory support for 4 months. The cause of respiratory arrest was not identified, but could be explained by the natural history of MSA. The bereaved family, who had suspected malpractice, was satisfied with the explanation based on the investigation performed by eight expert doctors, one expert nurse, two coordinator nurses and two lawyers in the model project promoted by the Japanese government.

Comparison of standard endoscopic submucosal dissection (ESD) versus an optimized ESD technique for the colon: an animal study

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is a promising therapeutic technique for en bloc resection of large gastrointestinal tumors. However, this technique has disadvantages such as a long intervention time, complexity of the procedure, and a higher rate of complications. The primary aims of the study were to show the feasibility of ESD in the pig colon and to evaluate a new ESD technique comprising the use of a newly developed hybrid knife for colon procedures combining RF (radiofrequency) application and a distance-dependent water-jet application.

MATERIALS AND METHODS

ESD was conducted at three different locations in the colon according to the computer-generated randomization list, using either the standard technique (injection needle, flex knife, and hook knife as therapeutic instruments and DRY CUT and SWIFT COAG as RF currents), or the new ESD technique (hybrid knife as the therapeutic instrument combined with the new cutting mode ENDO CUT D) in 12 healthy pigs. The perforation and bleeding rates were documented and statistically analyzed. Intervention time, resected specimen size, thermal and mechanical damage of the resection bed, and number of instrument changes required were also recorded.

RESULTS

A total of 16 and 18 ESD procedures were performed by the standard and new techniques, respectively. Complete en bloc resection was achieved in all cases. The standard ESD technique showed a perforation rate of 25 % (4/16) whereas the new ESD technique resulted in a 5.5 % perforation rate (1/18) ( P = 0.035); bleeding rates were similar. The new ESD technique was significantly safer compared with the standard ESD technique.

CONCLUSIONS

A new ESD technique for the successful en bloc resection in thin-walled regions such as pig colon has been described. This procedure is as effective as the standard procedure but is easier to handle and significantly safer.

Endoscopic submucosal dissection for treatment of mesopharyngeal and hypopharyngeal carcinomas

BACKGROUND AND STUDY AIMS

Application of the endoscopic submucosal dissection (ESD) technique, as well as elevation of the larynx in cooperation with an otolaryngologist, under general anesthesia has enabled en-block resection of early mesopharyngeal and hypopharyngeal carcinomas. The aim of this study was to retrospectively evaluate the safety of ESD and the efficacy of the elevation of the larynx for treatment of early mesopharyngeal and hypopharyngeal carcinomas.

PATIENTS AND METHODS

The study included 16 lesions in 13 patients who underwent ESD. To provide a sufficient working space, the larynx was elevated under direct laryngoscopy, and a tube was inserted and fixed onto the laryngeal side using the slot on the back of the laryngoscope.

RESULTS

The median maximum diameter of the lesions was 12.5 mm (range 2 - 37 mm). The en-block resection rate was 93.8 %. Lateral surgical margins in two patients were difficult to evaluate for technical reasons. The tube could not be removed from four patients on the day of the procedure due to laryngeal edema caused by the local injection. No serious complications were observed. Oral food intake was possible after a mean of 3.3 postoperative days.

CONCLUSIONS

With adequate intraoperative and postoperative management, ESD with elevation of the larynx may be very efficient and safe for endoscopic treatment of pharyngeal lesions.

Feasibility of electrocautery snaring as the final step of endoscopic submucosal dissection for stomach epithelial neoplasms

BACKGROUND

Endoscopic submucosal dissection (ESD) is a novel endoluminal technique that permits the resection of gastric neoplasms.

AIM

To analyse the feasibility of snaring as the final step of ESD.

PATIENTS AND METHODS

One hundred and ninety-nine consecutive gastric neoplasms resected by four ESD experts from January 2004 to May 2007 were investigated. Forty-five (22.6%) were finally resected finally using a snare. Rates of en bloc resection, complete (R0 plus en bloc) resection, mean operation time, and complications were assessed between the snaring and the non-snaring groups.

RESULTS

En bloc resection rate was significantly lower and delayed bleeding rate was significantly higher in the snaring group than in the non-snaring group (91.1% [41/45] vs. 100% [154/154], 11.1% [5/45] vs. 1.9% [3/154], respectively), although complete resection rate (86.7% [39/45] vs. 92.9% [143/154]) and mean operation time (70.2 min vs. 75.8 min) were not significantly different between the two groups. Six perforation cases (3 [6.7%] in the snaring group, 3 [1.9%] in the non-snaring group) were observed, but snaring did not lead to perforation in any case. When the subjects were divided into small (< or = 2 cm) and large (> 2 cm) tumours, en bloc resection rate in large tumours was still significantly different between the groups (76.9% [10/13] vs. 100% [67/67]), whereas in small tumours it was no longer significantly different (96.9% [31/32] vs. 100% [87/87]).

CONCLUSIONS

Snaring may facilitate successful ESD for smaller tumours, but multiple-piece resection should be taken into account especially for larger tumours.

Efficacy and safety of endoscopic submucosal dissection for gastric cancer in patients with liver cirrhosis

Endoscopic submucosal dissection (ESD) has become a widely accepted method for treating gastrointestinal cancer. The aim of this study was to evaluate the efficacy and safety of ESD for gastric cancer in patients with liver cirrhosis. A total of 18 gastric cancers were treated by ESD in 15 patients with cirrhosis. The rate of en bloc resection was 88.9% (16/18). En bloc resection with tumor-free lateral/basal margins (R0 resection) was 77.8% (14/18). Three patients had postoperative bleeding and underwent emergency gastroscopy for hemostasis. No recurrence was observed during the median follow-up of 21.4 months, excluding three patients in whom additional endoscopic resection or surgery was carried out. ESD can be safely performed for gastric cancer in patients with cirrhosis, resulting in a high en bloc resection rate.

Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is a novel technique used for the treatment of gastrointestinal neoplasia. One of its major limitations, however, is the complication of perforation.

PATIENTS AND METHODS

We included in our study all the cases of perforation that occurred during ESD procedures for gastrointestinal epithelial neoplasia between February 2000 and February 2005. Clinical outcomes after perforation were investigated.

RESULTS

Perforation was experienced at 27 lesions in 27 patients (four in the esophagus, fourteen in the stomach, seven in the colon, and two in the rectum). Fibrosis under the lesions was confirmed histologically in seven patients (26 %). Immediate closure using endoclips was performed in all patients except for three asymptomatic patients in whom a stomach perforation was first noticed when free air was noticed on a radiograph the morning after the ESD procedure. Air accumulation was detected radiographically in 21 patients (78 %). The mean duration of antibiotic treatment was 6.7 days and the patients were fasted for a mean period of 5.3 days. The mean maximum body temperature was 37.3 degrees C, the mean white blood cell count was 9733/mm3, and the mean C-reactive protein level was 5.0 mg/dl. All the patients were discharged well from the ward after a mean time of 12.1 days after ESD, and no recurrence caused by tumor spread from the perforation occurred in any patient after a median follow-up period of 36 months (range 9 - 52 months).

CONCLUSION

Successful nonsurgical management after ESD complicated by perforation is a highly feasible option if intensive conservative treatments are used following immediate endoscopic closure of the perforation.

Correlation of serum pepsinogens and gross appearances combined with histology in early gastric cancer

The correlation between serum pepsinogen (PG) levels and the gross types was investigated in 128 consecutive patients with early gastric cancer. Although there was no significant difference in age, gender, cancer location, or cancer depth among gross appearances, the distribution of histological type was significantly different between polypoid and depressed cancers: all polypoid cancers except one were intestinal type, whereas nearly a third of depressed cancers were diffuse type. All the patients in whom Helicobacter pylori status was investigated had Helicobacterpylori infection. Combination of gross appearances and histology (polypoid cancer with intestinal type, depressed cancer with intestinal type and depressed cancer with diffuse type) showed a clear difference in distribution of serum PG levels and a ratio between levels of PG I and PG II (I/II ratio). In polypoid cancer with intestinal type, a PG I level and a I/II ratio were significantly lower than those of the others. In depressed cancer with diffuse type, PG I and PG II levels were significantly higher. These findings revealed that backgrounds such as intragastric acidity and extent of gastric atrophy might differ among early gastric cancers with different morphology and histology.

Endoscopic submucosal dissection for rectal epithelial neoplasia

BACKGROUND AND STUDY AIMS

The technique of endoscopic submucosal dissection (ESD) has recently been developed for en-bloc resection of gastric tumors. For oncological reasons and in order to improve the patients' quality of life, it may be desirable to use the same technique for rectal neoplasia.

PATIENTS AND METHODS

Thirty-five consecutive patients with rectal neoplasia who had a preoperative diagnosis of large intraepithelial neoplasias with submucosal fibrosis or located on the rectal folds were enrolled. ESD was carried out with the same technique previously described for the stomach, with some modifications. The efficacy, complications, and follow-up results of the treatment were assessed.

RESULTS

The rates of en-bloc resection and en-bloc plus R0 resection were 88.6 % (31 of 35) and 62.9 % (22 of 35), respectively. Hemoglobin levels did not drop by more than 2 g/dl in any of the patients after ESD. None of the patients had to receive blood transfusions or undergo emergency colonoscopy due to bleeding during ESD or hematochezia after ESD. Perforation during ESD occurred in two patients (5.7 %), who were managed with conservative medical treatment after endoscopic closure of the perforation. Excluding three patients in whom additional surgery was carried out, all but one of 32 patients were free of recurrence during a mean follow-up period of 36 months (range 12 - 60 months). The exception was a patient in whom a multiple-piece resection was required; the recurrent (residual) tumor, found 2 months after ESD, was a small adenoma that was again treated endoscopically.

CONCLUSIONS

ESD is applicable in the rectum with promising results, but the technique is still at a developmental stage and patients should be informed of the potential risks.

Histopathologic characteristics of gastric ulcers created by endoscopic submucosal dissection

BACKGROUND AND STUDY AIM

We have previously reported that gastric ulcers artificially created by endoscopic submucosal dissection (ESD) would heal within 8 weeks regardless of size and location. The details of the healing process remain unclear, and we aimed to clarify the mechanism by histopathological investigation.

PATIENTS AND METHODS

21 post-ESD ulcers were examined histopathologically, using surgically resected specimens from patients who had subsequently undergone gastrectomy due to submucosal invasion and/or lymphovascular infiltration by the tumor. The grade of ulcer, appearance of regenerative mucosa, scar formation, and extent of fibrosis were evaluated.

RESULTS

Fibrosis and wall thickening were observed from 2 weeks after ESD, but regenerative mucosa was not observed until 5 weeks. Among 12 patients who underwent gastrectomy later than 8 weeks after ESD, a mucosal defect was still observed in two patients. In these two patients the lesion was associated with severe fibrosis due to previous peptic ulcer or submucosal invasion by the lesion.

CONCLUSION

Size reduction in these ulcers occurs by contraction in the early phase, then regenerative mucosa covers the remaining mucosal defect within 8 weeks. If there is fibrosis under the lesion before ESD, there is a possibility that the artificially created ulcer will not heal within 8 weeks.

Endoscopic submucosal dissection for gastric neoplasia: experience with the flex-knife

Although the standard treatment for gastric neoplasia is still surgical resection, endoscopic resection has been accepted for some of these lesions in an early stage. Among several methods of endoscopic resection, endoscopic submucosal dissection has been developed to remove the lesions in an en bloc fashion regardless of size, shape, coexisting ulcer, and location. However, indication of endoscopic submucosal dissection is strictly confined by two aspects; those are the possibility of nodal metastases and technical difficulty. Nowadays, several knives for endoscopic submucosal dissection are available and each of them has some merits and demerits. We describe how to perform endoscopic submucosal dissection in the stomach by using the flex-knife, a new endoscopic device specifically designed for submucosal dissection, emphasizing its special features from our experience.

Efficacy and safety of endoscopic submucosal dissection for tumors of the esophagogastric junction

BACKGROUND AND STUDY AIMS

The esophagogastric junction (EGJ) has been considered a difficult location for endoscopic treatment of tumors, due to its narrow lumen and sharp angle. Endoscopic submucosal dissection (ESD) is a method of endoscopic resection, capable of removing large tumors in an en bloc fashion. The aim of this study was to evaluate the efficacy and safety of ESD for EGJ tumors.

PATIENTS AND METHODS

For 30 lesions of EGJ tumors treated by ESD, the size of the lesions and resected specimens, the en bloc resection rate, complications, and local recurrence were assessed.

RESULTS

The average maximum diameters of the lesions and resected specimens were 22.4 mm and 40.6 mm respectively. The complete en bloc resection (R0) rate was 97% (29/30). Histological evaluation of the resected specimens revealed five cases of angiolymphatic invasion and five cases of submucosal invasion deeper than 500 microm. Perforation occurred in one case but was safely managed by rotatable clips and administration of antibiotics for 3 days. Local recurrence was not observed in any patient during follow-up (mean 14.6 months, range 6-31 months).

CONCLUSIONS

ESD can be safely performed for EGJ tumors, with a high en bloc resection rate. For lesions with no apparent submucosal invasion findings, ESD is a curative and diagnostic treatment option that may be considered before open surgery.

The useful combination of a higher frequency miniprobe and endoscopic submucosal dissection for the treatment of T1 esophageal cancer

BACKGROUND

There are few published data on the discrimination ability of endoscopic ultrasonography (EUS) among each subdivision of T1 cancer, and overdiagnosis is an unsolved problem that eventually causes overtreatment. The purpose of this study was to verify whether our treatment strategy incorporating EUS realizes a tailored patient management of T1 esophageal cancer.

METHODS

This study comprised 20 esophageal cancer patients undergoing 12- to 20-MHz miniprobes for T staging and a 7.5-MHz dedicated echoendoscope for N staging. Initial therapy constituted endoscopic submucosal dissection (ESD) for endosonographically node-negative, mucosal, or slight submucosal cancers and a primary esophagectomy with three-field lymphadenectomy for deeper cancers. If the ESD specimen revealed no cancer involvement of the muscularis mucosa, the patients entered a follow-up program; otherwise, they were advised to undergo a subsequent esophagectomy and three-field lymphadenectomy.

RESULTS

Perfect discrimination accuracy was achieved among T1, T2, and T3 cancers. Whether cancer depth was up to the slight submucosal layer or deeper was correctly differentiated in 12 of 14 T1 cancers (86%). EUS categorized all patients correctly into candidates for either ESD or surgery. The pathological cancer depth of the resected specimens revealed that no patients experienced unnecessary overtreatment.

CONCLUSIONS

A higher frequency miniprobe is useful for the detailed evaluation of cancer depth, contributing to decision making for treatment options of T1 esophageal cancer. A miniprobe and echoendoscope in combination with ESD provide an appropriately tailored management plan on an individual basis, avoiding unnecessary treatment or indicating radical surgery.

Epidemiological and outcome characteristics of major burns in Tokyo

The Tokyo Burn Unit Association (TBUA) was established in 1983 funded by the Tokyo Metropolitan Government, and is organized by 13 burn units in Tokyo. TBUA covers more than 90% of severe burn patients occurring in Tokyo, and all of the cases are registered according to the burn injury registration format. The purpose of this study is to analyze the registered data and to elucidate epidemiological and outcome characteristics of major burn injuries in Tokyo. The total of 6988 hospitalized patients had data for epidemiological analysis, and 6401 patients had complete data for outcome analysis as well, and were included in this study. The characteristic profiles for the analysis included age, sex, cause of burns, inhalation injury, %BSA, burn index (BI), length of burn unit stay, and outcome, and were analyzed by age groups. The mean age of the patients was 40.4 years, and 63% of them were male. It was noteworthy that 25% of the total patients were elderly patients over 60 years of age. Flame was the most common cause making up 45.6% followed by scalding (32.0%). The overall mortality rate was 15.4%. Inhalation injury was accompanied in 27.3% of burn patients. The mortality rate was 34.6% with inhalation injury, and 8.2% without inhalation injury. Causes of death showed that multiple organ failure made up 36.9% of total mortality, followed by sepsis 25.2 and shock 19.0%. The burn size (%BSA and BI) and inhalation injury were the factors for high mortality rate in all age groups whereas age was a predictor for high mortality in the patients older than 16 years of age. Gender was not a factor for high mortality in any age group. The mortality rate showed mildly decreasing tendency since 1995 for which implementation of skin bank was thought to be responsible.

Different mixtures of sodium hyaluronate and their ability to create submucosal fluid cushions for endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

Sodium hyaluronate (SH) is a promising submucosal injection solution during endoscopic mucosal resection, but its high cost is an obstacle to more widespread use. The aim of this study was to identify an appropriate low-cost SH solution by varying the molecular weight of SH and mixing various solutions with it.

MATERIALS AND METHODS

The viscoelasticity of various SH solutions was first measured. The concentrations of two 1 % SH preparations with different molecular weights (800 kDa and 1900 kDa) were adjusted to 0.5 %, 0.25 %, and 0.125 %, using 0.9 %/3.75 % normal saline (NS), 5 %/20 % dextrose water (DW), and a glycerin solution (Glyceol): 10 % glycerin with 0.9 % normal saline plus 5 % fructose. The ability of these SH solutions to create submucosal fluid cushions (SFCs) was then investigated in the stomachs of two live minipigs.

RESULTS

The 0.25 % 1900 kDa SH/NS solution and the 0.125 % 1900 kDa SH/20 % DW solution created a similar viscoelasticity to that of the 0.5 % 800 kDa SH/NS solution. The ability of these solutions to create SFCs was also similar. In addition, the 0.125 % 1900 kDa SH/Glyceol solution created similar SFCs, with a synergistic effect of increased viscoelasticity and the hypertonic nature of glycerin.

CONCLUSIONS

A mixture of higher molecular weight sodium hyaluronate with a sugar solution (particularly 20 % dextrose), with or without glycerin, should be regarded as a cost-effective option for creating SFCs instead of the conventional SH solution made with the same amount of a 1 % 800 kDa SH preparation and normal saline.

Comparison of various submucosal injection solutions for maintaining mucosal elevation during endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

One of the major complications of endoscopic mucosal resection (EMR) for gastrointestinal tumors is perforation, and the most effective way of preventing perforation is to elevate the lesion sufficiently by endoscopic injection of fluid into the submucosa.

MATERIALS AND METHODS

In order to compare the lesion-lifting properties of several different solutions, 1 ml of each of the following solutions was injected into the submucosa of the resected porcine stomach: normal saline, 3.75 % NaCl, 20 % dextrose water, 10 % glycerin with 0.9 % NaCl plus 5 % fructose, and two sodium hyaluronate (SH) solutions.

RESULTS

Significantly higher initial elevation was produced by both SH solutions, and it remained higher than that achieved by the other solutions at all times. Hypertonic solutions, especially 10 % glycerin with 0.9 % NaCl plus 5 % fructose, tended to produce and maintain greater mucosal elevation than normal saline, but the difference was not significant.

CONCLUSIONS

SH solutions were the most suitable ones for producing and maintaining long-term mucosal elevation, while the superiority of hypertonic solutions over normal saline was not clearly demonstrated.

Kinetics of v-src-induced epithelial-mesenchymal transition in developing glandular stomach

The oncogene function in primary epithelial cells is largely unclear. Recombination organ cultures in combination with the stable and transient gene transfer techniques by retrovirus and electroporation, respectively, enable us to transfer oncogenes specifically into primary epithelial cells of the developing avian glandular stomach (proventriculus). In this system, the epithelium and mesenchyme are mutually dependent on each other for their growth and differentiation. We report here that either stable or transient expression of v-src in the epithelium causes budding and migration of epithelial cells into mesenchyme. In response to the transient expression of v-Src or a constitutive active mutant of MEK, we observed immediate downregulation of the Sonic hedgehog gene and subsequent elimination of E-cadherine expression in migrating cells, suggesting the involvement of MAP kinase signaling pathway in these processes. v-src-expressing cells that were retained in the epithelium underwent apoptosis (anoikis) and detached from the culture. Continuous expression of v-src by, for example, Rous sarcoma virus (RSV) was required for the epithelial cells to acquire the ability to express type I collagen and fibronectin genes (mesenchymal markers), and finally to establish the epithelial-mesenchymal transition. These observations would partly explain why RSV does not apparently cause carcinoma formation, but induces sarcomas exclusively.

Extensive mesenteric vein and portal vein thrombosis successfully treated by thrombolysis and anticoagulation

Mesenteric vein thrombosis is generally difficult to diagnose and can be fatal. A case of extensive thrombosis of the mesenteric and portal veins was diagnosed early and successfully treated in a 26-year-old man with Down syndrome who was admitted to hospital because of abdominal pain, severe nausea and high fever. Ultrasonography revealed moderate ascites, and there was minimal flow in the portal vein (PV) on the Doppler examination. Computed tomography (CT) showed remarkable thickening of the walls of the small intestine and extensive thrombosis of the mesenteric, portal and splenic veins. Because neither intestinal infarction nor peritonitis was seen, combined thrombolysis and anticoagulation therapy without surgical treatment was chosen. Urokinase was administered intravenously and later through a catheter in the superior mesenteric artery. Heparin and antibiotics were given concomitantly. The patient's symptoms and clinical data improved gradually. After 10 days, CT revealed that collateral veins had developed and the thrombi in the distal portions of the mesenteric veins had dissolved, although the main trunk of the PV had not recanalized. The only risk factor of thrombosis that was detected was decreased protein S activity.

Severe hypercholesterolemia, hypertriglyceridemia, and atherosclerosis in mice lacking both leptin and the low density lipoprotein receptor

Leptin-deficient mice (ob/ob) are an excellent murine model for obesity, insulin resistance, and diabetes, all of which are components of a multiple risk factor syndrome that, along with hypercholesterolemia, precipitates a potential high risk for atherosclerosis. In the current study, we show an unexpectedly severe hyperlipidemia in ob/ob mice on a background of low density lipoprotein receptor (LDLR) deficiency (-/-). Doubly mutant mice (LDLR-/-;ob/ob) exhibited striking elevations in both total plasma cholesterol (TC) and triglyceride (TG) levels (1715 +/- 87 and 1016 +/- 172 mg/dl, respectively), at age 3-4 months, resulting in extensive atherosclerotic lesions throughout the aorta by 6 months. Lipoprotein analyses revealed the elevated TC and TG levels to be due to a large increase in an apoB-containing broad-beta remnant lipoprotein fraction. While fasting, diet restriction, and low level leptin treatment significantly lowered TG levels, they caused only slight changes in TC levels. Hepatic cholesterol and triglyceride contents as well as mRNA levels of cholesterologenic and lipogenic enzymes suggest that leptin deficiency increased hepatic triglyceride production but did not change cholesterol production in ob/ob mice regardless of their LDLR genotype. These data provide evidence that the hypertriglyceridemia and hypercholesterolemia in the doubly mutant mice are caused by distinct mechanisms and point to the possibility that leptin might have some impact on plasma cholesterol metabolism, possibly through an LDLR-independent pathway. This model will be an excellent tool for future studies on the relationship between impaired fuel metabolism, increased plasma remnant lipoproteins, diabetes, and atherosclerosis.

Cardiac arrest associated with use of an argon beam coagulator during laparoscopic cholecystectomy

We describe a cardiac arrest during use of an argon beam coagulation (ABC) system in an 82-yr-old woman having laparoscopic cholecystectomy under general and epidural anaesthesia. Intra-abdominal pressure (IAP) was controlled to less than 12 mm Hg during a carbon dioxide gas pneumoperitoneum and at first the operation was uneventful. When the ABC system (gas flow 6 litre min(-1)) was used to control local bleeding in the liver bed abdominal pressure increased rapidly to over 20 mm Hg and, 1 min later, the end-tidal carbon dioxide decreased to zero, followed by bradycardia and cardiac arrest. At once, an emergency laparotomy was performed and resuscitation begun. A mill-wheel murmur was heard on auscultation, leading to suspicion of argon gas embolism. Fortunately, recovery was completed with no neurological deficit. Anaesthesiologists should consider showed that argon gas embolism can occur with the ABC system during laparoscopic surgery.

Characterization of a membrane-bound arginine-specific serine protease from rat intestinal mucosa

Previously we isolated and characterized a membrane-bound, arginine-specific serine protease from pig intestinal mucosa [J. Biol. Chem. 269, 32985-32991 (1994)]. For further characterization of this type of enzyme, we cloned a cDNA from rat intestinal mucosa encoding the precursor of a similar protease. The partial amino acid sequences determined for the pig enzyme were found to be shared almost completely by the rat enzyme. The serine protease domain of the rat enzyme, heterologously expressed in Escherichia coli, specifically cleaved Arg (or Lys)-X bonds with a marked preference for Arg-Arg or Arg-Lys, similar to the pig enzyme. The mRNA for the rat enzyme was shown to be distributed mainly in intestine, and the enzyme was detected in the duodenal mucosa as a 70 kDa protein. Immunohistochemical analysis of the small intestinal tissue showed that the enzyme is localized mainly on brushborder membranes.

Identification of liver X receptor-retinoid X receptor as an activator of the sterol regulatory element-binding protein 1c gene promoter

In an attempt to identify transcription factors which activate sterol-regulatory element-binding protein 1c (SREBP-1c) transcription, we screened an expression cDNA library from adipose tissue of SREBP-1 knockout mice using a reporter gene containing the 2.6-kb mouse SREBP-1 gene promoter. We cloned and identified the oxysterol receptors liver X receptor (LXRalpha) and LXRbeta as strong activators of the mouse SREBP-1c promoter. In the transfection studies, expression of either LXRalpha or -beta activated the SREBP-1c promoter-luciferase gene in a dose-dependent manner. Deletion and mutation studies, as well as gel mobility shift assays, located an LXR response element complex consisting of two new LXR-binding motifs which showed high similarity to an LXR response element recently found in the ABC1 gene promoter, a reverse cholesterol transporter. Addition of an LXR ligand, 22(R)-hydroxycholesterol, increased the promoter activity. Coexpression of retinoid X receptor (RXR), a heterodimeric partner, and its ligand 9-cis-retinoic acid also synergistically activated the SREBP-1c promoter. In HepG2 cells, SREBP-1c mRNA and precursor protein levels were induced by treatment with 22(R)-hydroxycholesterol and 9-cis-retinoic acid, confirming that endogenous LXR-RXR activation can induce endogenous SREBP-1c expression. The activation of SREBP-1c by LXR is associated with a slight increase in nuclear SREBP-1c, resulting in activation of the gene for fatty acid synthase, one of its downstream genes, as measured by the luciferase assay. These data demonstrate that LXR-RXR can modify the expression of genes for lipogenic enzymes by regulating SREBP-1c expression, providing a novel link between fatty acid and cholesterol metabolism.

Asialoglycoprotein receptor deficiency in mice lacking the major receptor subunit. Its obligate requirement for the stable expression of oligomeric receptor

The asialoglycoprotein receptor is an abundant hetero-oligomeric endocytic receptor that is predominantly expressed on the sinusoidal surface of the hepatocytes. A number of physiological and pathophysiological functions have been ascribed to this hepatic lectin (HL), the removal of desialylated serum glycoproteins and apoptotic cells, clearance of lipoproteins, and the sites of entry for hepatotropic viruses. The assembly of two homologous subunits, HL-1 and HL-2, is required to form functional, high affinity receptors on the cell surface. However, the importance of the individual subunits for receptor transport to the cell surface is controversial. We have previously generated HL-2-deficient mice and showed that the expression of HL-1 was significantly reduced, and the functional activity as the asialoglycoprotein receptor was virtually eliminated. However, we failed to detect phenotypic abnormalities. To explore the significance of the major HL-1 subunit for receptor expression and function in vivo, we have disrupted the HL-1 gene in mice. Homozygous HL-1-deficient animals are superficially normal. HL-2 expression in the liver is virtually abrogated, indicating that HL-1 is strictly required for the stable expression of HL-2. Although these mice are almost unable to clear asialo-orosomucoid, a high affinity ligand for asialoglycoprotein receptor, they do not accumulate desialylated glycoproteins or lipoproteins in the plasma.

Causes of airway obstruction during cuffed oropharyngeal airway use

This study investigated the cause for needing airway maneuvers to maintain a patent airway during the use of cuffed oropharyngeal airway (COPA). Twenty adult patients (29.4+/-6.8 years-old, ASA 1-2) scheduled for minor gynecological surgery who required brief manipulations of the airway despite COPA use following the manufacture's guidelines, were enrolled in this study. To obtain airway patency, 15 patients required only the head-tilt maneuver. In eight of the 15 patients, the laryngeal inlet was opened partially (n=4) or completely (n=4). Despite lifting the epiglottis, the laryngeal inlet was incomplete at the level of pharyngeal view. The patency of the laryngeal inlet was decided by the extent of the distance between the posterior pharyngeal wall and the lateral glossoepiglottic fold, which was made by hyoid bone. In the other seven patients, the head-tilt maneuver elevated the epiglottis and completely opened the laryngeal inlet. Five patients required both the jaw-thrust and head-tilt maneuver. Of these patients lifting the epiglottis was incomplete in three and the laryngeal inlet was partially collapsed in one even after the airway manipulations. The airways in these three patients, however, became patent after manipulations despite the persisting partial obstruction.

Troglitazone inhibits atherosclerosis in apolipoprotein E-knockout mice: pleiotropic effects on CD36 expression and HDL

Atherosclerotic coronary heart disease is a common complication of the insulin resistance syndrome that can occur with or without diabetes mellitus. Thiazolidinediones (TZDs), which are insulin-sensitizing antidiabetic agents, can modulate the development of atherosclerosis not only by changing the systemic metabolic conditions associated with insulin resistance but also by exerting direct effects on vascular wall cells that express peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a nuclear receptor for TZDs. Here we show that troglitazone, a TZD, significantly inhibited fatty streak lesion formation in apolipoprotein E-knockout mice fed a high-fat diet (en face aortic surface lesion areas were 6.9+/-2.5% vs 12.7+/-4.7%, P<0.05; cross-sectional lesion areas were 191 974+/-102 911 micrometer(2) vs 351 738+/-175 597 micrometer(2), P<0.05; n=10). Troglitazone attenuated hyperinsulinemic hyperglycemia and increased high density lipoprotein cholesterol levels. In the aorta, troglitazone markedly increased the mRNA levels of CD36, a scavenger receptor for oxidized low density lipoprotein, presumably by upregulating its expression, at least in part, in the macrophage foam cells. These results indicate that troglitazone potently inhibits fatty streak lesion formation by modulating both metabolic extracellular environments and arterial wall cell functions.

Psoas abscess complicating Crohn's disease: report of a case

We describe herein the case of a psoas abscess complicating Crohn's disease, and present a review of the literature on this unusual disease entity. A 22-year-old Japanese man with a 5-year history of Crohn's ileocolitis presented with right lower abdominal and hip pain, and a diagnosis of right psoas abscess was subsequently made by abdominal computed tomography (CT). Following the administration of antibiotics and CT-guided percutaneous drainage of the abscess, the patient's symptoms temporarily improved; however, 2 weeks later, the abscess cavity was found to have extended around the periarticular tissue of the right hip joint. To prevent the development of septic arthritis of the hip joint, surgical drainage of the abscess cavity and ileocecal resection were immediately performed, after which the patient's condition greatly improved. The resected specimen showed Crohn's ileocolitis with an external fistula in the terminal ileum which was considered to have caused the psoas abscess. Since psoas abscess in Crohn's disease can result in serious complications such as septic arthritis of the hip joint if left untreated, aggressive treatment should be initiated without delay.

The LDL receptor is the major pathway for beta-VLDL uptake by mouse peritoneal macrophages

In order to determine the contribution of the low density lipoprotein receptor (LDL-R) to the removal of apoB-containing native lipoproteins by macrophages, we compared the uptake of beta-VLDL in peritoneal macrophages (MPM) from wild type mice and mice lacking the LDL-R. The d<1.006 g/ml lipoproteins obtained from apoE deficient mice fed a high fat diet were poorly degraded by macrophages and caused only a slight formation of CE in macrophages from both types of mice. On the other hand, d<1.006 g/ml lipoproteins obtained from LDL-R deficient mice fed a high fat diet, beta-VLDL with apoE, were avidly taken up by and markedly stimulated CE formation in wild type macrophages, but not in macrophages lacking the LDL-R. The degradation of 125I-labeled-apoE-containing beta-VLDL by wild type MPM was poorly inhibited by unlabeled human LDL, and beta-VLDL without apoE had no effects. In conclusion, we propose that the in vitro uptake of native apoE-enriched lipoproteins by murine macrophages is primarily mediated by the LDL receptor and not by other apoE-recognizing receptor systems such as: the LDL receptor related protein, the VLDL receptor or the triglyceride-rich lipoprotein receptor.

Thiazolidinedione- and tumor necrosis factor alpha-induced downregulation of peroxisome proliferator-activated receptor gamma mRNA in differentiated 3T3-L1 adipocytes

Thiazolidinediones (TZDs) are antidiabetic insulin-sensitizing agents that bind to peroxisome proliferator-activated receptor gamma (PPARgamma) and have potent adipogenic effects on 3T3-L1 preadipocytes. In fully differentiated 3T3-L1 adipocytes, TZDs markedly decreased PPARgamma mRNA levels without reducing the expression of genes that are positively regulated by PPARgamma, such as adipocyte lipid-binding protein 2 (aP2) or lipoprotein lipase-(LPL). PPARgamma mRNA levels were also downregulated by tumor necrosis factor alpha (TNFalpha), an antiadipogenic cytokine. We propose that the downregulation of PPARgamma is not the common denominator of the metabolic effects of TZDs and TNFalpha on mature adipocytes.

Effect of electrolyzed water on wound healing

Electrolyzed water accelerated the healing of full-thickness cutaneous wounds in rats, but only anode chamber water (acid pH or neutralized) was effective. Hypochlorous acid (HOCl), also produced by electrolysis, was ineffective, suggesting that these types of electrolyzed water enhance wound healing by a mechanism unrelated to the well-known antibacterial action of HOCl. One possibility is that reactive oxygen species, shown to be electron spin resonance spectra present in anode chamber water, might trigger early wound healing through fibroblast migration and proliferation.