Kazuhiko Maekawa

Effects of sarin on the nervous system of subway workers seven years after the Tokyo subway sarin attack.

Effects of Sarin on the Nervous System of Subway Workers Seven Years after the Tokyo Subway Sarin Attack: Koichi Miyaki, et al. Department of Preventive Medicine and Public Health, School of Medicine, Keio University—This study was designed to assess the after effects of sarin exposure on the nervous system in victims of the Tokyo Subway Sarin Attack, which occurred on 20 March, 1995. We performed a similar study 3 yr after the disaster. This time, we newly enrolled 36 staff of the Teito Rapid Transit Authority (Tokyo Eidan subway) to assess the 7 yr after effects on the nervous system, and merged previous data including unpublished data to enhance statistical power. New subjects consisted of 23 male exposed subjects and 13 referent subjects matched for age and working types. Neurobehavioral tests for psychomotor function and memory, stabilometry, and Benton visual retention test were performed. As reported previously, the exposed group performed significantly less well in the psychomotor function test (tapping) than the referent group (117.8±1.2 vs. 105.6 ± 1.2 msec). Using merged data, this phenomenon was also observed in a dose‐dependent manner and the exposed group performed significantly less well in the backward digit span test (4.47 ± 1.17 vs. 5.11 ± 1.65 digits). These results indicate that chronic decline of psychomotor function and memory function still exist 7 yr after the sarin exposure.

Endoscopic retrograde cholangiography in the nonsurgical management of blunt liver injury

Injury to the intrahepatic bile duct has not been routinely examined in patients with blunt liver injury, despite the risk of formation of a biloma and hemobilia. In this study we examined the role of endoscopic retrograde cholangiography (ERC) in the evaluation of blunt liver injuries. Sixty-four of 106 (60.3%) patients with blunt hepatic injuries, admitted from April 1986 through March 1992, were managed nonsurgically; ERC was performed in conjunction with computed tomographic (CT) scanning to rule out injury to the bile duct in 28 patients. Injury to the bile duct was detected in six patients (21.4%), five of whom developed a biloma. Patients with hepatic parenchymal injuries that were observed on the CT scans were at greatest risk for injury to the intrahepatic bile duct, and our data suggested that the incidence of injury to the intrahepatic bile duct after blunt hepatic trauma is higher than previously reported. Patients with serious hepatic parenchymal injuries who are candidates for nonsurgical management should be considered for ERC to exclude the possibility of injury to the bile duct.

Characteristics of pancreatic injury in children: A comparison with such injury in adults

A retrospective study of eight pediatric patients (under 15 years of age) who had pancreatic injuries was undertaken. Comparisons were made with 59 adult patients who sustained pancreatic injuries over the same 15-year period. All the pediatric injuries and 96.6% of the adult resulted from blunt abdominal trauma. Bicycle accidents (children, 75.0%; adults, 0%; P < .001) and automobile accidents (children, 0%; adults, 61.0%; P < .01) were the most common causes of pancreatic injury in the two groups. There was no significant difference in the incidence of abdominal pain or peritoneal irritation between the groups. However, abdominal pain in the adults was poorly localized. Isolated pancreatic injuries were noted in 62.5% of the pediatric patients and in 15.3% of the adult patients (P < .05). Associated intraabdominal injuries were present in 25.0% of the children and in 69.5% of the adults (P < .05). The duodenum was injured in two (25.0%) pediatric patients and in 10 (16.9%) adult patients. Whereas the duodenal injuries in pediatric patients were intramural hematomas without perforation in both cases, all but one of these injuries in adults were perforations or transections (P < .05). There was a significant difference in the type of pancreatic injury between the two groups (P < .05). Surgery was performed in 12.5% of the pediatric cases and in 78.0% of the adult cases (P < .01). There were no deaths among the pediatric patients, but 8.5% of the adults died in the hospital. The difference with respect to clinical course might be related to the differences in cause of injury.

Iliac vein injuries in hemodynamically unstable patients with pelvic fracture caused by blunt trauma.

BACKGROUND Major pelvic venous injuries secondary to blunt trauma can be a difficult problem in diagnosis and management. This study aimed to elucidate the clinical significance of iliac vein injuries demonstrated by venography in patients with blunt pelvic injuries who remained unstable even after transcatheter arterial embolization (TAE). METHODS We reviewed the records of 72 patients with unstable pelvic fracture who presented with shock at our center after blunt trauma from 1999 through 2003. The average Injury Severity Score was 34.3 in this study population. RESULTS TAE was the first method of choice to control bleeding from pelvic fracture in 61 patients. Thirty-six patients recovered from shock after TAE. Eighteen of 25 who did not recover from shock died. In 11 of these 25, transfemoral venography with a balloon catheter was performed, revealing significant venous extravasation in 9: common iliac vein in 5, internal iliac vein in 3, and external iliac vein in 1. The average Injury Severity Score of patients with iliac vein injury was 45.8. Treatments for venous injuries were laparotomy for hemostasis (n = 1, survivors = 0), retroperitoneal gauze packing (n = 3, survivors = 1), and endovascular stent placement (n = 3, survivors = 3). Two patients suffered from cardiac arrest before treatment for venous injury. External fixations were performed after TAE according to fracture type. CONCLUSION The iliac vein injury is the principal cause of hemorrhagic shock in some patients with unstable pelvic fractures after blunt trauma. Venography is useful for identifying iliac vein injuries.

Neoendothelialization after peripheral blood stem cell transplantation in humans: a case report of a Tokaimura nuclear accident victim.

OBJECTIVES Neoendothelialization by circulating endothelial progenitor cells has been a topic of recent research. The extent and scale of this process in humans is not well understood. We examined the extent of neoendothelialization of the aorta and peripheral arteries in the case of a patient who underwent peripheral blood stem cell transplantation for acute radiation syndrome. METHODS Human tissue samples from the aorta and peripheral arteries were obtained at autopsy. Endothelial cells were isolated, confirmed by von Willebrand factor immunostaining, and then subjected to fluorescent in situ hybridization analysis using X- and Y-chromosome specific probes to examine neoendothelialization by donor cells as possible in this case in which the donor and recipient were of different genders. RESULTS The aorta showed almost 25% of all endothelial cells to be replaced by donor-origin endothelial cells. The peripheral arteries were also replaced but to a lesser extent. DISCUSSION The present study provides evidence that peripheral blood is a source of endothelial progenitor cells in humans. Neoendothelialization of the aorta occurs to a significant extent under certain conditions suggesting the potential for exploitation of therapeutic neovascularization by transplantation of circulating endothelial progenitor cells.

The role of angiography in the assessment of blunt liver injury.

Angiography and therapeutic embolism (TE) were studied retrospectively in cases of blunt liver injury with regard to their indications and usefulness. The management of patients fell into three groups distinguished by the clinical evidence of the severity of the liver injuries. The most severe 42 cases (39.6 per cent) were managed surgically and promptly, the least severe 38 cases were not subjected to angiography and the intermediate group (26 cases; 24.5 per cent) underwent angiography and 12/26 cases underwent TE. However, haemodynamic stability on admission was not significantly different between these groups. In addition, all patients who underwent angiography and TE had more severe parenchymal injury on imaging studies while their haemodynamic instability was not identified on admission. Angiography and TE for blunt liver injury were most strongly indicated in patients with good haemodynamic responses to intravenous fluid administration during the acute phase and/or in cases of severe parenchymal injury on imaging.

Large-volume intraoperative peritoneal lavage with an assistant device for treatment of peritonitis caused by blunt traumatic rupture of the small bowel

The benefits of large-volume intraoperative peritoneal lavage (IOPL), with an assistant lavage device, were evaluated retrospectively in 114 patients with peritonitis caused by blunt traumatic rupture of the small bowel. Postoperative complications caused by infection were a major problem after rupture of the small bowel (46 of 114, 39.4%). Both prolongation of the interval between injury and laparotomy and rupture of the lower part of the small bowel were risk factors for postoperative complications caused by infection. Large-volume IOPL (25.2 +/- 2.1 L) with an assistant lavage device reduced the rate of complications caused by infection from 30 of 58 (51.8%) to 15 of 56 (26.8%). The volume used for IOPL was closely related to the occurrence of postoperative complications resulting from infection. No complications from infection occurred in patients who received lavage with of 28.3 +/- 2.7 L of saline, whereas complications occurred in those patients treated with a smaller volume of lavage fluid (18.0 +/- 2.5 L). Large-volume IOPL should be considered in patients with blunt rupture of the small bowel who are at risk for infection, and the assistant device for IOPL may be useful for such treatment.

Hypoxia-reoxygenation inhibits gap junctional communication in cultured human umbilical vein endothelial cells.

We studied the change in gap junctional intercellular communication (GJIC) on human umbilical vein endothelial cells (HUVEC) under hypoxia-reoxygenation (H-R) conditions by the fluorescence redistribution after photobleaching (FRAP) method. Confluent HUVEC monolayers were exposed to hypoxia (pO2<0.1%) for 12 hours, and then were returned to normal atmospheric conditions for reoxygenation. Contrast microscopic observation showed no significant changes in the morphology of the HUVEC at any times after H-R. Reoxygenation following hypoxia caused time-dependent decrease in GJIC, that is, GJIC reduction was induced after 2 hours and reached maximum at 4-6 hours which recovered to normal levels after 18 hours. Oxidant sensitive fluorescence dye assay revealed that the generation of intracellular free radicals increased during the first 2 hours after reoxygenation. Hydroxyl radical scavengers (MCI-186, DMSO) and an iron chelator (deferoxamine) abolished the reduction of GJIC due to H-R. However, SOD, catalase and probucol were essentially inactive on this reduction. These data suggest that ischemia-reperfusion injury may be caused by a functional defect of GJIC induced by reactive oxygen radicals.

Role of repeat computed tomography after emergency endoscopic retrograde pancreatography in the diagnosis of traumatic injury to pancreatic ducts

Endoscopic retrograde pancreatography (ERP) is performed on patients with pancreatic injury after abdominal trauma. To delineate pancreatic ductal injuries more accurately, we performed repeat computed tomography (CT) shortly after completion of ERP. We describe our experiences with six patients to demonstrate the feasibility and utility of this method. In our cases, the diagnosis of pancreatic ductal injury was made with certainty on the basis of the presence of extravasated contrast medium. This protocol is useful for reaffirmation of injuries noted on ERP, for diagnosis of injuries not noted on ERP, and for exclusion of injuries in patients with equivocal results of ERP. Moreover, the protocol is easy to implement because it involves only the transfer of the patient from the endoscopy to the CT suite. The technique can be used to clarify potentially confusing situations.

Effects of tyrosine kinase signaling inhibition on survival after cecal ligation and puncture in diet-restricted mice.

BACKGROUND Malnutrition impairs host immunity, resulting in high mortality and morbidity due to infections. Phosphorylation of protein tyrosine kinase (PTK) is a key step in the signaling of many cellular functions, including immune cell functions. Malnutrition may affect this signaling in response to surgical insults. The aim of this study was to examine the effects of PTK inhibition on mortality in ad libitum and in diet-restricted mice after cecal ligation and puncture (CLP). Moreover, tyrosine phosphorylation of peritoneal cells from these animals was evaluated. METHODS Survival study: Mice (n = 45) received chow, 146 g/kg per day (ad libitum) or 36.5 g/kg per day (diet-restricted), for 7 days. Two hours before CLP, one-half the mice in each group were given a tyrosine kinase inhibitor, AG 556 (3.0 mg/kg i.p.), and the others received vehicle. Survival was observed up to 7 days after CLP. Effects of AG 556 on survival with a lesser degree of malnutrition (chow 73 g/kg per day) were also examined (n = 41). Measurement of tyrosine phosphorylation: mice (n = 20) were assigned to the ad libitum and diet-restricted (chow 36.5 g/kg per day) groups. Peritoneal cells were harvested either before or 2 hours after glycogen injection. Glycogen treatment elicits polymorphonuclear neutrophil influx into the peritoneal cavity. The cells were incubated with or without N-formyl-methionyl-leucyl-phenylalanine (fMLP). Tyrosine phosphorylation in the cells was examined using flow cytometry, laser scanning cytometry, and Western blotting. RESULTS Diet restriction significantly reduced survival compared with the ad libitum group. AG 556 treatment decreased the survival of ad libitum, but not in diet-restricted mice in both survival experiments. Stimulation of peritoneal cells with fMLP increased tyrosine phosphorylation in the ad libitum group (23% increase before glycogen and 18% after glycogen), but not in the diet-restricted group (-9% before glycogen and 3% after glycogen). CONCLUSIONS Inhibition of tyrosine kinase signaling impairs the ability of a well-nourished host to survive CLP-induced sepsis, while having no effects on survival in diet-restricted mice. Peritoneal cells from diet-restricted animals are unable to increase PTK phosphorylation in response to stimulation, which may be the mechanism underlying impaired host defense during malnutrition.