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61.
Hematin is one of the cytotoxic factors in pancreatitis-associated ascitic fluid that causes hepatocellular injury. 总被引:7,自引:0,他引:7
Takashi Ueda Yoshifumi Takeyama Kozo Takase Yuichi Hori Yoshikazu Kuroda Hung S Ho 《Surgery》2002,131(1):66-74
BACKGROUND: We recently demonstrated that pancreatitis-associated ascitic fluid (PAAF) contains cytotoxic factor(s), inducing apoptosis in hepatocytes, and that PAAF induces hepatic adenosine triphosphate depletion, hepatocellular acidosis, and accumulation of hepatic intracellular sodium. Because ascitic fluid and serum from patients with hemorrhagic pancreatitis contain a lot of hematin, we aimed to test the hypothesis that hematin can induce hepatocellular injury, and then we compared its cytotoxicity with that of PAAF. METHODS: In vivo effects of intraperitoneal injection of hematin into the liver of healthy rats were evaluated with in situ nick-end labeling, blood biochemical analysis, and nuclear magnetic resonance spectroscopy. In vitro cytotoxic and apoptosis-inducing activities of hematin on rat primary culture hepatocytes were investigated with a cellular proliferation assay kit and DNA fragmentation enzyme-linked immunosorbent assay, respectively. Furthermore, PAAF was fractionated with Sephacryl S-300 gel column chromatography, and cytotoxic activities of its fractions on a human hepatoma cell line (HuH-7) were compared with those of hematin. RESULTS: Intraperitoneal injection of hematin into healthy rats caused apoptosis in the hepatocytes and elevated serum glutamate oxaloacetic transaminase and lactate dehydrogenase levels. Intraperitoneal injection of hematin also caused a significant decrease in the hepatic beta-adenosine triphosphate/inorganic phosphate ratio, severe hepatic intracellular acidosis, and a significant increase of hepatic intracellular sodium (Na(+)) concentration, similar to the effects of PAAF. In vitro, hematin decreased hepatocyte viability and increased the DNA fragmentation of hepatocytes, similar to the effects of 10% PAAF. Albumin reversed the cytotoxic effects of hematin and PAAF on HuH-7 cells nearly completely and partially, respectively. Fractionation of PAAF and hematin by gel column chromatography revealed that the first peak of cytotoxic activity of PAAF corresponded to that of hematin and that the cytotoxic activity was reversed by albumin nearly completely. CONCLUSIONS: These results suggest that hematin is one of the cytotoxic factors in PAAF that causes hepatocellular injury and that cellular injuries caused by hematin may be involved in the development of multiple organ failure associated with severe acute pancreatitis. 相似文献
62.
Keisuke Goto Naoya Tajima Etsuo Chosa Koji Totoribe Hiroshi Kuroki Yuichi Arizumi Takashi Arai 《Journal of orthopaedic science》2002,7(2):243-246
We established a three-dimensional finite element method (FEM) model of the 4th and 5th vertebrae, using computed tomography
(CT) images (2-mm slice thickness) of a healthy 29-year-old man. Because of the lack of specific data regarding the material
characteristics of the nucleus pulposus of intervertebral discs, we used intradiscal pressure in the nucleus pulposus to establish
the model. We referred to data from Nachemson and from Sato et al. regarding intradiscal pressure and to the methods of Shirazi-Adl
for data for other material characteristics (see text for these references). The mid-position model bears a load of 294 N
in the vertical direction, while the models of the flexed and extended positions bear loads of 15 N-m. In addition, a degenerative
disc model without intradiscal pressure was created for the standing model. The use of these models allowed the investigation
of von Mises stress on the vertebral endplates and the annulus fibrosus. We also examined von Mises stress on the facet joint
in normal and degenerative disc models. There was increased von Mises stress on the vertebral endplate in the anterior, center
portions. von Mises stress on the annulus fibrosus increased in the posterior portion, the entrance to the neural foramen,
and the exit of the neural foramen. von Mises stress was greater during flexion in the posterior portion; in particular, increasing
to about 1.6 times the level seen with other postures. No changes were observed in von Mises stress on the vertebral endplates
or annulus fibrosus in the degenerative disc model, but von Mises stress on the facet joints was about 2.5 times that seen
in the normal disc model.
Received: June 28, 2001 / Accepted: October 27, 2001 相似文献
63.
Makoto Shinzeki Yuichi Hori Yasuhiro Fujino Ippei Matsumoto Hirochika Toyama Toshiaki Tsujimura Tetsuya Sakai Tetsuo Ajiki Yoshikazu Kuroda Yonson Ku 《Surgery today》2010,40(5):470-473
Hemosuccus pancreaticus (HP) is mostly induced by a ruptured pseudoaneurysm or hemorrhage from a pseudocyst in chronic pancreatitis.
We herein report a rare case with HP induced by tumor hemorrhage. The present patient is a 71-year-old woman referred to us
with a diagnosis of severe progressive anemia. Endoscopy revealed hemorrhage from the papilla of Vater. Computed tomography
showed a multilocular cystic tumor in the tail of the pancreas. The patient underwent a distal pancreatectomy. The histopathological
diagnosis was carcinoma in mucinous cystadenoma. No cancer infiltration into the pancreatic duct was detected. Pancreatography
of the resected specimen demonstrated an overt communication between the main pancreatic duct and the cystic cavity of the
tumor, which was not demonstrated preoperatively by endoscopic retrograde pancreatography. Although the cause of HP is mainly
acute or chronic pancreatitis, we should bear in mind that a pancreatic tumor may be a possible cause of HP and that, as such,
prompt and proper treatment is mandatory. 相似文献
64.
Verica Aleksic Akira Aoki Kengo Iwasaki Aristeo Atsushi Takasaki Chen-Ying Wang Yoshimitsu Abiko Isao Ishikawa Yuichi Izumi 《Lasers in medical science》2010,25(4):559-569
Although the use of high-level Er:YAG laser irradiation has been increasing in periodontal and peri-implant therapy, the effects
of low-level Er:YAG laser on surrounding tissues and cells remain unclear. In the present study, the effects of low-level
Er:YAG laser irradiation on osteoblast proliferation were investigated. Cells of the osteoblastic cell line MC3T3-E1 were
treated with low-level Er:YAG laser irradiation with various combinations of laser settings (fluence 0.7–17.2 J/cm2) and in the absence or presence of culture medium during irradiation. On day 1 and/or day 3, cell proliferation and death
were determined by cell counting and by measurement of lactate dehydrogenase (LDH) levels. Further, the role of mitogen-activated
protein kinase (MAPK) pathways in laser-enhanced cell proliferation was investigated by inhibiting the MAPK pathways and then
measuring MAPK phosphorylation by Western blotting. Higher proliferation rates were found with various combinations of irradiation
parameters on days 1 and 3. Significantly higher proliferation was also observed in laser-irradiated MC3T3-E1 cells at a fluence
of approximately 1.0–15.1 J/cm2, whereas no increase in LDH activity was observed. Further, low-level Er:YAG irradiation induced the phosphorylation of extracellular
signal-regulated protein kinase (MAPK/ERK) 5 to 30 min after irradiation. Although MAPK/ERK 1/2 inhibitor U0126 significantly
inhibited laser-enhanced cell proliferation, activation of stress-activated protein kinases/Jun N-terminal kinase (SAPK/JNK)
and p38 MAPK was not clearly detected. These results suggest that low-level Er:YAG laser irradiation increases osteoblast
proliferation mainly by activation of MAPK/ERK, suggesting that the Er:YAG laser may be able to promote bone healing following
periodontal and peri-implant therapy. 相似文献
65.
A 58-year-old woman underwent laparoscopy-assisted transverse colectomy for transverse colon cancer. On postoperative day
7, she experienced sudden abdominal pain accompanied by vomiting and fever. Computed tomography showed a small bowel obstruction
caused by an internal hernia. Laparotomy revealed an internal hernia through the mesenteric defect at the anastomotic colonic
stumps, which had not been closed in the previous operation. Almost the entire small bowel protruding through the mesenteric
defect was found in the omental bursa. We resected part of the jejunal loop, which was strangulated and congested by an adherent
band. Our experience suggests that if the mesenteric defect is relatively small, it should be closed completely during laparoscopy-assisted
colectomy; however, more studies are required to determine the indications for closure of the mesenteric defect to prevent
this complication. 相似文献
66.
Usuba T Misawa T Toyama Y Ishida Y Ishii Y Yanagisawa S Kobayashi S Yanaga K 《Surgery today》2011,41(1):97-100
Purpose
Gastrojejunostomy is often performed as palliative surgery for unresectable pancreatobiliary cancer. Modified Devine exclusion (MDE) is a technical variation of gastrojejunostomy, which partially separates the mid-portion of the stomach. We conducted this study to assess whether MDE is necessary for gastrojejunostomy in patients with unresectable pancreatobiliary cancer. 相似文献67.
Furuno Y Nishimura S Kamiyama H Numagami Y Saito A Kaimori M Nishijima M 《Neurologia medico-chirurgica》2008,48(2):72-76
A 15-year-old man presented with headache. Magnetic resonance (MR) imaging revealed a large extraaxial tumor with cyst at the right frontotemporal region. The solid part of the tumor was homogeneously enhanced on T(1)-weighted MR imaging after injection of gadolinium. Digital subtraction angiography of the external carotid artery revealed sunburst appearance corresponding to the tumor, which was fed by the right middle meningeal artery. His headache worsened and computed tomography revealed enlargement of the tumor and intracystic hemorrhage, so emergent operation was performed. At surgery, the tumor strongly adhered to the dural membrane, and was obviously extraaxial. The tumor and cyst were gross totally removed. The attachment site at the dura mater was resected. Histological examination showed solid growth of small round cells with uniform round nuclei and minimal cytoplasm. Immunohistochemical staining showed the cells were positive for MIC-2 (CD99). The MIB-1 labeling index was 53%. The histological diagnosis was peripheral-type primitive neuroectodermal tumor (pPNET). Following surgery, radiation therapy and chemotherapy were given. Ewing's sarcoma and pPNET form a family of small round cell tumors arising in the bone or soft tissue. MIC-2 is a useful marker in the differential diagnosis. Good prognosis may be attained if complete surgical excision of intracranial pPNET is achieved. 相似文献
68.
Maruyama H Aoki A Sasaki KM Takasaki AA Iwasaki K Ichinose S Oda S Ishikawa I Izumi Y 《Lasers in surgery and medicine》2008,40(3):211-222
BACKGROUND AND OBJECTIVES: This study compared the surface morphology as well as the biocompatibility of dental root cementum treated with Er:YAG laser irradiation alone and with the laser irradiation followed by chemical and/or mechanical conditioning. STUDY DESIGN/MATERIALS AND METHODS: Healthy cementum plates were randomly assigned to the following control and treatment groups: (1) untreated control (C), (2) Er:YAG laser irradiation (L), (3) laser plus tetracycline HCl (TC) placement (L+TP), (4) laser plus TC burnishing (L+TB), (5) laser plus EDTA gel placement (L+EP), (6) laser plus EDTA gel burnishing (L+EB), (7) laser plus saline solution burnishing (L+SB), and (8) laser plus minocycline-HCl paste placement (L+MP). Specimens were subjected to scanning electron microscopy (SEM), histological observation and attachment assay using periodontal ligament (PDL) fibroblasts. RESULTS: The laser irradiation produced a thin affected layer (5.7 microm thickness) with a superficial microstructure on the cementum surface. The characteristic microstructures of the lased surface were fragile and could be removed by chemical and/or mechanical conditioning treatments. The L+TB group exhibited marked exposure of collagen fibers after removal of the microstructures on the lased surface. The L+EP group presented a peculiar, smooth surface without exposure of collagen fibers and a uniform arrangement of spherical microparticles on the ultra-high magnification of SEM. In cell attachment assay, the L+TB group exhibited the greatest number of attached cells among all the groups, followed by the L+EP, L+SB and control group. The laser alone group exhibited the lowest number of cells. CONCLUSIONS: The characteristic microstructure of the root cementum surface after Er:YAG laser irradiation has a tendency to hinder the early attachment of PDL cells. However, chemical and/or mechanical root conditioning treatment may improve and increase the biocompatibility of the Er:YAG laser-treated root cementum by removing the microstructures of the surface and/or further exposing the collagen fibers. 相似文献
69.
Ueshima H Asai T Shingu K Inoue H Hashimoto Y Enomoto Y Okuda Y 《Masui. The Japanese journal of anesthesiology》2008,57(1):82-84
Pentax-AWS laryngoscope (Pentax, Tokyo, Japan) consists of a disposable anatomically shaped blade, a 12-cm cable with a charge-coupled device (CCD) camera and a 2.4-inch liquid crystal device (LCD) color monitor display. A tracheal tube can be attached to the right side of the blade. The device may be useful in patients with difficult airways. One limitation of the device is that intubation may be difficult if it is difficult to position the glottis to the target symbol on the monitor display. We experienced such a difficulty in four patients, and the use of a gum elastic bougie enabled intubation. In a 57-year-old woman with a difficult airway, tracheal intubation using either a Macintosh laryngoscope or a fiberscope had failed. By inserting the AWS laryngoscope, the glottis was easily seen on the monitor display. Nevertheless, it was difficult to position the glottis to the target symbol, and advancing a tracheal tube collided with the tissue around the glottis. A bougie was passed through the tracheal tube, and it became possible to insert the bougie into the trachea by adjusting the angle of its tip. The tracheal tube was then easily passed over the bougie into the trachea. We successfully used the same technique in other three patients. We believe that the gum elastic bougie can be useful for tracheal intubation using the Pentax-AWS laryngoscope. 相似文献
70.
BACKGROUND: We studied the prevalence of postoperative complications and the predictor for the occurrence of postoperative delirium in patients who had received surgery for femoral neck fracture. METHODS: A retrospective study, covering the period between January 1, 2005 and March 31, 2006, was carried out 50 in patients of advanced age treated for femoral neck fracture. We investigated main symptoms of postoperative complications. We also compared postoperative delirium group (D group) with no delirium group (ND group). RESULTS: The following results were obtained. Main postoperative complications were delirium, hypotension and hypoxia. And only one death case was included. In postoperative delirium, there was not a wide difference between the two groups except for hearing loss. CONCLUSIONS: Our results indicate that it might be possible to prevent postoperative complications by careful perioperative management. Hearing loss preoperatively was a risk factor of postoperative delirium in advanced elderly patients. 相似文献