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Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic.  相似文献   
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ABSTRACT

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Glioblastoma is one of the most lethal tumors in adult central nervous system with a median survival of a year and half and effective therapeutic strategy is urgently needed. For that reason, stem cell-based suicide gene therapies have attracted much interest because of potent tumor tropism of stem cells and bystander effect. In this current clinical situation, stem cells are promising delivery tool of suicide genes for glioma therapy. Since habitual cigarette smoking still prevails worldwide, we investigated the effect of nicotine on stem cell tropism toward glioma and gap junctional intercellular communication (GJIC) function between glioma and stem cells, both of which are important for suicide gene therapies. Methods: Mouse induced pluripotent stem cell-derived neural stem cells (iPS-NSCs) and human dental pulp mesenchymal stem cells (DPSCs) were used. The effect of nicotine on tumor tropism to glioma-conditioned medium (CM) at a non-cytotoxic concentration was assessed with Matrigel invasion assay. Nicotine effect on GJIC was assessed with the scrape loading/dye transfer (SL/DT) assay for co-culture of glioma and stem cells and the parachute assay among glioma cells using high-content analysis. Results: Tumor tropism of iPS-NSCs toward GL261-CM and DPSCs toward U251-CM was not affected by nicotine (0.1 and 1 µM). Nicotine at the concentrations equivalent to habitual smoking (1 µM) did not affect GJIC of iPS-NSC/GL261 and DPSC/U251 and GJIC among each glioma cells. Conclusions: The study demonstrated that non-cytotoxic concentrations of nicotine did not significantly change the stem cell properties requisite for stem cell-based suicide gene therapy.  相似文献   
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This study describes a novel technique for skeletonization and isolation of Glissonean and venous branches during liver surgery using a harmonic scalpel (HS). Hepatic resections with HS were performed with the skeletonization and isolation technique in 50 patients (HS group). Variables evaluated were blood loss, operative time, biliary leak, and morbidity. The results were compared with 50 hepatic resections that were performed using a previously established technique: Cavitron ultrasonic surgical aspirator with electric cautery, ligatures, and hemoclips (NHS group). The HS group had shorter total operative times (285 versus 358 minutes; P = 0.01), less blood loss (389 versus 871 mL; P = 0.034), and less crystalloid infusion (2744 versus 3299 mL; P = 0.027) compared with the NHS group. Postoperative liver function and complication rates were similar when comparing the two groups. These data demonstrate that HS is a simple, easy, and effective instrument for the skeletonization and isolation of vessels during liver transection.Key words: Liver resection, Ultrasonic scalpel, Skeletonization, Cavitation effectVarious devices are available for liver transection, but the availability of comparative data for transection techniques is limited by the diversity of operative procedures. Clamp crushing (CC) and a Cavitron ultrasonic surgical aspirator are widely used for splitting the liver parenchyma,1,2 and hemostasis is achieved by bipolar coagulation, ligatures, or hemoclips. Various coagulating devices, such as Ligasure,3 Tissuelink,4 and the Harmonic Scalpel (HS),57 have recently been developed to aid in liver splitting. The choice of instrument is often based on individual surgeon preference. Higami et al8,9 described a novel technique to skeletonize and harvest the internal thoracic artery with the HS, and the present study capitalizes on their experience to describe a unique method to skeletonize and isolate the Glissonean and venous branches using an HS.  相似文献   
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“Soft pancreas” has often been reported as a predictive factor for postoperative pancreatic fistula (POPF) after pancreatectomy. However, pancreatic stiffness is judged subjectively by surgeons, without objective criteria. In the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated. Forty-one patients (pancreatoduodenectomy, 30; distal pancreatectomy, 11) who underwent intraoperative elastography during pancreatectomy were included. The elastic ratio was determined at the pancreatic resection site (just above the portal vein) and at the remnant pancreas (head or tail). Correlations between the incidence of POPF and patient characteristics, operative variables, and the elastic ratio were examined. In addition, the relationship between the elastic ratio and the percentage of the exocrine gland at the resection stump was investigated. For pancreatoduodenectomy patients, main pancreatic duct diameter < 3.2 mm and elastic ratio < 2.09 were significant risk factors for POPF. In addition, the elastic ratio, but not main pancreatic duct diameter, was significantly associated with the percentage of exocrine gland area at the pancreatic resection stump. Pancreatic stiffness can be quantified using intraoperative elastography. Elastography can be used to diagnose “soft pancreas” and may thus be useful in predicting the occurrence of POPF.Key words: Elastography, Exocrine gland, Pancreatectomy, Pancreatic stiffness, Postoperative pancreatic fistulaDespite current advances in surgical techniques, pancreatectomy is a very difficult procedure associated with the risk of multiple postoperative complications. The morbidity and mortality are reported to be 20–50% and 1–5%, respectively.1 In particular, a postoperative pancreatic fistula (POPF) can sometimes lead to life-threatening complications, such as hemoperitoneum and sepsis. The worldwide incidence of POPF is reported to be 5–50%. Several predictive factors for POPF have been reported to date, and, of these, “soft pancreas” has often been mentioned.24 However, in all of these reports, evaluation of pancreatic stiffness has depended on subjective judgment by the surgeon, without objective parameters as criteria.Elastography has recently been developed to enable real-time visualization of the relative stiffness of tissue elasticity, and its usefulness in various clinical disciplines for tumor diagnosis and differential diagnosis has been described.5 In gastroenterology, evaluation of liver fibrosis and diagnosis of pancreatic tumors and chronic pancreatitis using endoscopic ultrasound (EUS) have been reported,6,7 but the use of elastography in surgery has not been reported. An objective assessment of pancreatic stiffness as a predictive risk factor for POPF can help in choosing the intraoperative surgical technique and in planning the postoperative management strategy. Therefore, in the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated.  相似文献   
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The purpose of this study was to evaluate the effect of acidic primers on bonding magnetic steel alloys. Three alloys (XM27, 447J1, and AUM20) were primed with one of the following materials: Acryl Bond, Estenia Opaque Primer, Eye Sight Opaque Primer, M. L. Primer, or Super-Bond liquid. The specimens were bonded with a tri-n-butylborane initiated resin, and bond strength was determined both before and after thermocycling in water. Unprimed specimen was considered as the control. Average bond strength varied from 0 to 45.3 MPa for the XM27 alloy, 0.3 to 43.6 MPa for the 447J1 alloy, and 0.5 to 41.1 MPa for the AUM20 alloy. Of the five primers, Estenia Opaque Primer exhibited better adhesive performance than the other materials regardless of the type of steel alloy. It can be concluded that the use of the Estenia Opaque Primer, which contains an adhesive monomer (10-methacryloyloxydecyl dihydrogen phosphate; MDP), is recommended for bonding the three magnetic steel alloys with TBB-initiated resin.  相似文献   
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